{"id":4509,"date":"2020-08-15T02:11:14","date_gmt":"2020-08-14T18:11:14","guid":{"rendered":"https:\/\/damogame.cn\/wordpress\/?p=4509"},"modified":"2020-08-15T02:11:14","modified_gmt":"2020-08-14T18:11:14","slug":"linux%e5%86%85%e5%ad%98%e7%ae%a1%e7%90%86%e4%b9%8bslab%e5%88%86%e9%85%8d%e5%99%a8","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/4509","title":{"rendered":"Linux\u5185\u5b58\u7ba1\u7406\u4e4bSLAB\u5206\u914d\u5668"},"content":{"rendered":"
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\u539f\u6587\u5730\u5740<\/a><\/div>\n
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\u5206\u7c7b\u4e13\u680f\uff1a<\/span>\u00a0Linux\u5185\u5b58\u7ba1\u7406<\/a><\/div>\n<\/div>\n
\u7248\u6743<\/a><\/div>\n<\/div>\n<\/div>\n<\/div>\n
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\u6ce8\uff1a\u672c\u6587\u8bb2\u8ff0\u7684SLAB\u76f8\u5173\u4ee3\u7801\u662f\u57fa\u4e8eLinux\u5185\u6838v4.7\uff0c\u4ee3\u7801\u7f51\u5740<\/a>\u3002<\/p>\n

1\u3001SLAB\u5206\u914d\u5668\u7684\u7531\u6765<\/p>\n

\u5728\u8bb2SLAB\u5206\u914d\u5668\u4e4b\u524d\u5148\u8bf4\u4e24\u4e2a\u6982\u5ff5\uff1a \u5185\u90e8\u788e\u7247\u548c\u5916\u90e8\u788e\u7247\u3002<\/p>\n

\u5916\u90e8\u788e\u7247<\/a>\u6307\u7684\u662f\u8fd8\u6ca1\u6709\u88ab\u5206\u914d\u51fa\u53bb\uff08\u4e0d\u5c5e\u4e8e\u4efb\u4f55\u8fdb\u7a0b\uff09\u4f46\u7531\u4e8e\u592a\u5c0f\u800c\u65e0\u6cd5\u5206\u914d\u7ed9\u7533\u8bf7\u5185\u5b58\u7a7a\u95f4\u7684\u65b0\u8fdb\u7a0b\u7684\u5185\u5b58\u7a7a\u95f2\u533a\u57df\u3002\u5916\u90e8\u788e\u7247\u662f\u9664\u4e86\u4efb\u4f55\u5df2\u5206\u914d\u533a\u57df\u6216\u9875\u9762\u5916\u90e8\u7684\u7a7a\u95f2\u5b58\u50a8\u5757\u3002\u8fd9\u4e9b\u5b58\u50a8\u5757\u7684\u603b\u548c\u53ef\u4ee5\u6ee1\u8db3\u5f53\u524d\u7533\u8bf7\u7684\u957f\u5ea6\u8981\u6c42\uff0c\u4f46\u662f\u7531\u4e8e\u5b83\u4eec\u7684\u5730\u5740\u4e0d\u8fde\u7eed\u6216\u5176\u4ed6\u539f\u56e0\uff0c\u4f7f\u5f97\u7cfb\u7edf\u65e0\u6cd5\u6ee1\u8db3\u5f53\u524d\u7533\u8bf7\u3002\u7b80\u5355\u793a\u4f8b\u5982\u4e0b\u56fe\uff1a<\/p>\n

\"\"<\/p>\n

\u5982\u679c\u67d0\u8fdb\u7a0b\u73b0\u5728\u9700\u8981\u5411\u64cd\u4f5c\u7cfb\u7edf\u7533\u8bf7\u5730\u5740\u8fde\u7eed\u768432K\u5185\u5b58\u7a7a\u95f4\uff0c\u6ce8\u610f\u662f\u5730\u5740\u8fde\u7eed\uff0c\u5b9e\u9645\u4e0a\u7cfb\u7edf\u4e2d\u5f53\u524d\u5171\u670910K+23K=33K\u7a7a\u95f2\u5185\u5b58\uff0c\u4f46\u662f\u8fd9\u4e9b\u7a7a\u95f2\u5185\u5b58\u5e76\u4e0d\u8fde\u7eed\uff0c\u6240\u4ee5\u4e0d\u80fd\u6ee1\u8db3\u8fdb\u7a0b\u7684\u8bf7\u6c42\u3002\u8fd9\u5c31\u662f\u6240\u8c13\u7684\u5916\u90e8\u788e\u7247\uff0c\u9020\u6210\u5916\u90e8\u788e\u7247\u7684\u539f\u56e0\u4e3b\u8981\u662f\u8fdb\u7a0b\u6216\u8005\u7cfb\u7edf\u9891\u7e41\u7684\u7533\u8bf7\u548c\u91ca\u653e\u4e0d\u540c\u5927\u5c0f\u7684\u4e00\u7ec4\u8fde\u7eed\u9875\u6846\u3002Linux\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u4e3a\u4e86\u5c3d\u91cf\u907f\u514d\u5916\u90e8\u788e\u7247\u800c\u91c7\u7528\u4e86\u4f19\u4f34\u7cfb\u7edf\uff08Buddy System\uff09\u7b97\u6cd5\u3002<\/p>\n

\u5185\u90e8\u788e\u7247<\/a>\u5c31\u662f\u5df2\u7ecf\u88ab\u5206\u914d\u51fa\u53bb\uff08\u80fd\u660e\u786e\u6307\u51fa\u5c5e\u4e8e\u54ea\u4e2a\u8fdb\u7a0b\uff09\u5374\u4e0d\u80fd\u88ab\u5229\u7528\u7684\u5185\u5b58\u7a7a\u95f4\uff1b\u5185\u90e8\u788e\u7247\u662f\u5904\u4e8e\u533a\u57df\u5185\u90e8\u6216\u9875\u9762\u5185\u90e8\u7684\u5b58\u50a8\u5757\uff0c\u5360\u6709\u8fd9\u4e9b\u533a\u57df\u6216\u9875\u9762\u7684\u8fdb\u7a0b\u5e76\u4e0d\u4f7f\u7528\u8fd9\u4e2a\u5b58\u50a8\u5757\uff0c\u800c\u5728\u8fdb\u7a0b\u5360\u6709\u8fd9\u5757\u5b58\u50a8\u5757\u65f6\uff0c\u7cfb\u7edf\u65e0\u6cd5\u5229\u7528\u5b83\u3002\u76f4\u5230\u8fdb\u7a0b\u91ca\u653e\u5b83\uff0c\u6216\u8fdb\u7a0b\u7ed3\u675f\u65f6\uff0c\u7cfb\u7edf\u624d\u6709\u53ef\u80fd\u5229\u7528\u8fd9\u4e2a\u5b58\u50a8\u5757\u3002\u7b80\u5355\u793a\u4f8b\u5982\u4e0b\u56fe\uff1a<\/p>\n

\"\"<\/p>\n

\u67d0\u8fdb\u7a0b\u5411\u7cfb\u7edf\u7533\u8bf7\u4e863K\u5185\u5b58\u7a7a\u95f4\uff0c\u7cfb\u7edf\u901a\u8fc7\u4f19\u4f34\u7cfb\u7edf\u7b97\u6cd5\u53ef\u80fd\u5206\u914d\u7ed9\u8fdb\u7a0b4K\uff08\u4e00\u4e2a\u6807\u51c6\u9875\u9762\uff09\u5185\u5b58\u7a7a\u95f4\uff0c\u5bfc\u81f4\u5269\u4f591K\u5185\u5b58\u7a7a\u95f4\u65e0\u6cd5\u88ab\u7cfb\u7edf\u5229\u7528\uff0c\u9020\u6210\u4e86\u6d6a\u8d39\u3002\u8fd9\u662f\u7531\u4e8e\u8fdb\u7a0b\u8bf7\u6c42\u5185\u5b58\u5927\u5c0f\u4e0e\u7cfb\u7edf\u5206\u914d\u7ed9\u5b83\u7684\u5185\u5b58\u5927\u5c0f\u4e0d\u5339\u914d\u9020\u6210\u7684\u3002\u7531\u4e8e\u4f19\u4f34\u7b97\u6cd5\u91c7\u7528\u9875\u6846\uff08Page Frame\uff09\u4f5c\u4e3a\u57fa\u672c\u5185\u5b58\u533a\uff0c\u9002\u5408\u4e8e\u5927\u5757\u5185\u5b58\u8bf7\u6c42\u3002\u5728\u5f88\u591a\u60c5\u51b5\u4e0b\uff0c\u8fdb\u7a0b\u6216\u8005\u7cfb\u7edf\u7533\u8bf7\u7684\u5185\u5b58\u90fd\u662f4K\uff08\u4e00\u4e2a\u6807\u51c6\u9875\u9762\uff09\u7684\uff0c\u4f9d\u7136\u91c7\u7528\u4f19\u4f34\u7b97\u6cd5\u5fc5\u7136\u4f1a\u9020\u6210\u7cfb\u7edf\u5185\u5b58\u7684\u6781\u5927\u6d6a\u8d39\u3002\u4e3a\u6ee1\u8db3\u8fdb\u7a0b\u6216\u8005\u7cfb\u7edf\u5bf9\u5c0f\u7247\u5185\u5b58\u7684\u8bf7\u6c42\uff0c\u5bf9\u5185\u5b58\u7ba1\u7406\u7c92\u5ea6\u66f4\u5c0f\u7684SLAB\u5206\u914d\u5668\u5c31\u4ea7\u751f\u4e86\u3002\uff08\u6ce8\uff1aLinux\u4e2d\u7684SLAB\u7b97\u6cd5\u5b9e\u9645\u4e0a\u662f\u501f\u9274\u4e86Sun\u516c\u53f8\u7684Solaris\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u7684SLAB\u6a21\u5f0f\uff09<\/p>\n

2\u3001SLAB\u5206\u914d\u5668\u7b80\u4ecb<\/p>\n

SLAB\u5206\u914d\u5668\u5b9e\u9645\u4e0a\u662f\u5efa\u7acb\u5728\u4f19\u4f34\u7cfb\u7edf\u7b97\u6cd5\u4e4b\u4e0a\u7684\uff0cSLAB\u5206\u914d\u5668\u4f7f\u7528\u7684\u5185\u5b58\u7a7a\u95f4\u662f\u901a\u8fc7\u4f19\u4f34\u7b97\u6cd5\u8fdb\u884c\u5206\u914d\u7684\uff0c\u53ea\u4e0d\u8fc7SLAB\u5bf9\u8fd9\u4e9b\u5185\u5b58\u7a7a\u95f4\u5b9e\u73b0\u4e86\u81ea\u5df1\u7684\u7b97\u6cd5\u8fdb\u800c\u5bf9\u5c0f\u5757\u5185\u5b58\u8fdb\u884c\u7ba1\u7406\u3002<\/p>\n

\u5728\u8bb2\u89e3SLAB\u539f\u7406\u524d\uff0c\u6211\u4eec\u8003\u8651\u4e0b\u9762\u573a\u666f\uff1a\u5982\u679c\u4e00\u4e2a\u5e94\u7528\u7a0b\u5e8f\u7ecf\u5e38\u4f7f\u7528\u67d0\u4e00\u79cd\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u6216\u8005\u8bf4\u9891\u7e41\u7684\u521b\u5efa\u3001\u56de\u6536\u67d0\u4e00\u79cd\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u90a3\u6211\u4eec\u662f\u4e0d\u662f\u53ef\u4ee5\u5c1d\u8bd5\u5c06\u8fd9\u7c7b\u5bf9\u8c61\u5355\u72ec\u5b58\u653e\u8d77\u6765\uff0c\u5f53\u8fdb\u7a0b\u4e0d\u5728\u4f7f\u7528\u65f6\uff0c\u6211\u4eec\u6682\u65f6\u5148\u4e0d\u56de\u6536\uff0c\u7b49\u5e94\u7528\u7a0b\u5e8f\u518d\u4f7f\u7528\u65f6\uff0c\u6211\u4eec\u628a\u4e4b\u524d\u5e94\u8be5\u56de\u6536\u7684\u5bf9\u8c61\u5728\u62ff\u51fa\u6765\uff0c\u53ea\u4e0d\u8fc7\u91cd\u65b0\u6784\u9020\u4e00\u4e0b\u5bf9\u8c61\uff0c\u8fd9\u6837\u6211\u4eec\u5c31\u51cf\u5c11\u4e86\u4e00\u6b21\u91ca\u653e\u3001\u7533\u8bf7\u5185\u5b58\u7684\u64cd\u4f5c\u4e86\u3002<\/p>\n

\u6ce8\uff1a\u4e0b\u6587\u8bf4\u660e\u7684\u7f13\u5b58\u6307\u7684\u5e76\u4e0d\u662f\u771f\u6b63\u7684\u7f13\u5b58\uff0c\u771f\u6b63\u7684\u7f13\u5b58\u6307\u7684\u662f\u786c\u4ef6\u7f13\u5b58\uff0c\u4e5f\u5c31\u662f\u6211\u4eec\u901a\u5e38\u6240\u8bf4\u7684L1 cache\u3001L2 cache\u3001L3 cache\uff0c\u786c\u4ef6\u7f13\u5b58\u662f\u4e3a\u4e86\u89e3\u51b3\u5feb\u901f\u7684CPU\u548c\u901f\u5ea6\u8f83\u6162\u7684\u5185\u5b58\u4e4b\u95f4\u901f\u5ea6\u4e0d\u5339\u914d\u7684\u95ee\u9898\uff0cCPU\u8bbf\u95eecache\u7684\u901f\u5ea6\u8981\u5feb\u4e8e\u5185\u5b58\uff0c\u5982\u679c\u5c06\u5e38\u7528\u7684\u6570\u636e\u653e\u5230\u786c\u4ef6\u7f13\u5b58\u4e2d\uff0c\u4f7f\u7528\u65f6CPU\u76f4\u63a5\u8bbf\u95eecache\u800c\u4e0d\u7528\u518d\u8bbf\u95ee\u5185\u5b58\uff0c\u4ece\u800c\u63d0\u5347\u7cfb\u7edf\u901f\u5ea6\u3002\u4e0b\u6587\u4e2d\u7684\u7f13\u5b58\u5b9e\u9645\u4e0a\u662f\u7528\u8f6f\u4ef6\u5728\u5185\u5b58\u4e2d\u9884\u5148\u5f00\u8f9f\u4e00\u5757\u7a7a\u95f4\uff0c\u4f7f\u7528\u65f6\u76f4\u63a5\u4ece\u8fd9\u4e00\u5757\u7a7a\u95f4\u4e2d\u53bb\u53d6\uff0c\u662fSLAB\u5206\u914d\u5668\u4e3a\u4e86\u4fbf\u4e8e\u5bf9\u5c0f\u5757\u5185\u5b58\u7684\u7ba1\u7406\u800c\u5efa\u7acb\u7684\u3002<\/p>\n

3\u3001SLAB\u5206\u914d\u5668\u539f\u7406<\/p>\n

3.1 SLAB\u76f8\u5173\u8bf4\u660e<\/p>\n

\uff081\uff09SLAB\u4e0e\u4f19\u4f34\uff08Buddy\uff09\u7b97\u6cd5<\/p>\n

\u4f19\u4f34\u7cfb\u7edf\u7684\u76f8\u5173\u4ecb\u7ecd\u53ef\u4ee5\u53c2\u52a0\u5176\u4ed6\u535a\u5ba2\u3002\u5728\u4f19\u4f34\u7cfb\u7edf\u4e2d\uff0c\u6839\u636e\u7528\u6237\u8bf7\u6c42\uff0c\u4f19\u4f34\u7cfb\u7edf\u7b97\u6cd5\u4f1a\u4e3a\u7528\u6237\u5206\u914d2^order\u4e2a\u9875\u6846\uff0corder\u7684\u5927\u5c0f\u4ece0\u523011\u3002\u5728\u4e0a\u6587\u4e2d\uff0c\u63d0\u5230SLAB\u5206\u914d\u5668\u662f\u5efa\u7acb\u5728\u4f19\u4f34\u7cfb\u7edf\u4e4b\u4e0a\u7684\u3002\u7b80\u5355\u6765\u8bf4\uff0c\u5c31\u662f\u7528\u6237\u8fdb\u7a0b\u6216\u8005\u7cfb\u7edf\u8fdb\u7a0b\u5411SLAB\u7533\u8bf7\u4e86\u4e13\u95e8\u5b58\u653e\u67d0\u4e00\u7c7b\u5bf9\u8c61\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u4f46\u6b64\u65f6SLAB\u4e2d\u6ca1\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u6765\u4e13\u95e8\u5b58\u653e\u6b64\u7c7b\u5bf9\u8c61\uff0c\u4e8e\u662fSLAB\u5c31\u50cf\u4f19\u4f34\u7cfb\u7edf\u7533\u8bf72\u7684\u5e42\u6b21\u65b9\u4e2a\u8fde\u7eed\u7684\u7269\u7406\u9875\u6846\uff0cSLAB\u7684\u7533\u8bf7\u5f97\u5230\u4f19\u4f34\u7cfb\u7edf\u6ee1\u8db3\u4e4b\u540e\uff0cSLAB\u5c31\u5bf9\u8fd9\u4e00\u5757\u5185\u5b58\u8fdb\u884c\u7ba1\u7406\uff0c\u7528\u4ee5\u5b58\u653e\u591a\u4e2a\u4e0a\u6587\u4e2d\u63d0\u5230\u7684\u67d0\u4e00\u7c7b\u5bf9\u8c61\u3002<\/p>\n

\uff082\uff09SLAB\u4e0e\u5bf9\u8c61<\/p>\n

\u5bf9\u8c61\u5b9e\u9645\u4e0a\u6307\u7684\u662f\u67d0\u4e00\u79cd\u6570\u636e\u7c7b\u578b\u3002\u4e00\u4e2aSLAB\u53ea\u9488\u5bf9\u4e00\u79cd\u6570\u636e\u7c7b\u578b\uff08\u5bf9\u8c61\uff09\u3002\u4e3a\u4e86\u63d0\u5347\u5bf9\u5bf9\u8c61\u7684\u8bbf\u95ee\u6548\u7387\uff0cSLAB\u53ef\u80fd\u4f1a\u5bf9\u5bf9\u8c61\u8fdb\u884c\u5bf9\u9f50\u3002<\/p>\n

\uff083\uff09SLAB\u4e0eper-CPU\u7f13\u5b58<\/p>\n

\u4e3a\u4e86\u63d0\u5347\u6548\u7387\uff0cSLAB\u5206\u914d\u5668\u4e3a\u6bcf\u4e00\u4e2aCPU\u90fd\u63d0\u4f9b\u4e86\u6bcfCPU\u6570\u636e\u7ed3\u6784struct array_cache\uff0c\u8be5\u7ed3\u6784\u6307\u5411\u88ab\u91ca\u653e\u7684\u5bf9\u8c61\u3002\u5f53CPU\u9700\u8981\u4f7f\u7528\u7533\u8bf7\u67d0\u4e00\u4e2a\u5bf9\u8c61\u7684\u5185\u5b58\u7a7a\u95f4\u65f6\uff0c\u4f1a\u5148\u68c0\u67e5array_cache\u4e2d\u662f\u5426\u6709\u7a7a\u95f2\u7684\u5bf9\u8c61\uff0c\u5982\u679c\u6709\u7684\u8bdd\u5c31\u76f4\u63a5\u4f7f\u7528\u3002\u5982\u679c\u6ca1\u6709\u7a7a\u95f2\u5bf9\u8c61\uff0c\u5c31\u50cfSLAB\u5206\u914d\u5668\u8fdb\u884c\u7533\u8bf7\u3002<\/p>\n

3.2 SLAB\u76f8\u5173\u6570\u636e\u7ed3\u6784<\/p>\n

\u6ce8\u610f\uff0c\u672c\u8282\u8bf4\u660e\u7684SLAB\u4ee3\u7801\u662f\u57fa\u4e8eLinux\u5185\u6838v4.7\u7248\u672c\uff0c\u4ee3\u7801\u7f51\u5740<\/a>\u3002<\/p>\n

SLAB\u5206\u914d\u5668\u628a\u5bf9\u8c61\u5206\u7ec4\u653e\u8fdb\u9ad8\u901f\u7f13\u5b58\u3002\u6bcf\u4e2a\u9ad8\u901f\u7f13\u5b58\u90fd\u662f\u540c\u79cd\u7c7b\u578b\u5bf9\u8c61\u7684\u4e00\u79cd\u201c\u50a8\u5907\u201d\u3002\u5305\u542b\u9ad8\u901f\u7f13\u5b58\u7684\u4e3b\u5185\u5b58\u533a\u88ab\u5212\u5206\u4e3a\u591a\u4e2aSLAB\uff0c\u6bcf\u4e2aSLAB\u7531\u4e00\u4e2a\u6216\u591a\u4e2a\u8fde\u7eed\u7684\u9875\u6846\u7ec4\u6210\uff0c\u8fd9\u4e9b\u9875\u6846\u4e2d\u65e2\u5305\u542b\u5df2\u5206\u914d\u7684\u5bf9\u8c61\uff0c\u9875\u5305\u542b\u7a7a\u95f2\u7684\u5bf9\u8c61\u3002<\/p>\n

\u5728Linux\u5185\u6838\u4e2d\uff0cSLAB\u9ad8\u901f\u7f13\u5b58\u7528struct kmem_cache\u8868\u793a\uff0c\u6e90\u4ee3\u7801\u7f51\u5740<\/a>\uff0c\u5176\u5b9a\u4e49\u5982\u4e0b\uff1a<\/p>\n

<\/code><\/pre>\n
    \n
  1. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*SLAB\u5206\u914d\u5668\u9ad8\u901f\u7f13\u5b58*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  2. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> kmem_cache<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
  3. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u6bcfCPU\u9ad8\u901f\u7f13\u5b58\u6307\u9488\uff0c\u6bcf\u4e00\u4e2aCPU\u90fd\u4f1a\u6709\u4e00\u4e2a\u8be5\u7ed3\u6784\uff0c\u5176\u4e2d\u5b58\u653e\u4e86\u7a7a\u95f2\u5bf9\u8c61*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  4. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> array_cache<\/span> __percpu<\/span> *cpu_cache<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
  5. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  6. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* 1) Cache tunables. Protected by slab_mutex *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  7. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u8981\u8f6c\u79fb\u8fdb\u672c\u5730\u9ad8\u901f\u7f13\u5b58\u6216\u8005\u4ece\u672c\u5730\u9ad8\u901f\u7f13\u5b58\u4e2d\u8f6c\u79fb\u51fa\u53bb\u7684\u5bf9\u8c61\u7684\u6570\u91cf*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  8. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> batchcount;<\/div>\n<\/div>\n<\/li>\n
  9. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u672c\u5730\u9ad8\u901f\u7f13\u5b58\u4e2d\u7a7a\u95f2\u5bf9\u8c61\u7684\u6700\u5927\u6570\u76ee*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  10. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> limit;<\/div>\n<\/div>\n<\/li>\n
  11. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u662f\u5426\u5b58\u5728CPU\u5171\u4eab\u7684\u9ad8\u901f\u7f13\u5b58*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  12. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> shared;<\/div>\n<\/div>\n<\/li>\n
  13. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u5bf9\u8c61\u5bf9\u9f50\u4e4b\u540e\u6240\u5360\u5b57\u8282\uff0c\u4e5f\u5c31\u662f\u5bf9\u8c61\u672c\u8eab\u5927\u5c0f+\u4e3a\u5bf9\u9f50\u5bf9\u8c61\u800c\u586b\u5145\u7684\u5b57\u8282*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  14. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> size;<\/div>\n<\/div>\n<\/li>\n
  15. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*size\u7684\u5012\u6570*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  16. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> reciprocal_value<\/span> reciprocal_buffer_size<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
  17. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* 2) touched by every alloc & free from the backend *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  18. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u63cf\u8ff0\u9ad8\u901f\u7f13\u5b58\u6c38\u4e45\u5c5e\u6027\u7684\u4e00\u7ec4\u6807\u5fd7*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  19. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> flags; \/* constant flags *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  20. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u6bcf\u4e00\u4e2aSLAB\u4e2d\u5305\u542b\u7684\u5bf9\u8c61\u7684\u4e2a\u6570*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  21. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> num; \/* # of objs per slab *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  22. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  23. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* 3) cache_grow\/shrink *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  24. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u4e00\u4e2a\u5355\u72ecSLAB\u4e2d\u5305\u542b\u7684\u8fde\u7eed\u9875\u6846\u6570\u76ee\u7684\u5bf9\u6570 order of pgs per slab (2^n) *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  25. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> gfporder;<\/div>\n<\/div>\n<\/li>\n
  26. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  27. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* \u5206\u914d\u9875\u6846\u65f6\u4f20\u9012\u7ed9\u4f19\u4f34\u7cfb\u7edf\u7684\u4e00\u7ec4\u6807\u8bc6*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  28. \n
    \n
    <\/div>\n<\/div>\n
    \n
    gfp_t<\/span> allocflags;<\/div>\n<\/div>\n<\/li>\n
  29. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*SLAB\u4f7f\u7528\u7684\u989c\u8272\u7684\u6570\u91cf*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  30. \n
    \n
    <\/div>\n<\/div>\n
    \n
    size_t<\/span> colour;<\/div>\n<\/div>\n<\/li>\n
  31. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*SLAB\u4e2d\u57fa\u672c\u5bf9\u9f50\u504f\u79fb\uff0c\u5f53\u65b0SLAB\u7740\u8272\u65f6\uff0c\u504f\u79fb\u91cf\u7684\u503c\u9700\u8981\u4e58\u4e0a\u8fd9\u4e2a\u57fa\u672c\u5bf9\u9f50\u504f\u79fb\u91cf\uff0c\u7406\u89e3\u5c31\u662f1\u4e2a\u504f\u79fb\u91cf\u7b49\u4e8e\u591a\u5c11\u4e2aB\u5927\u5c0f\u7684\u503c*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  32. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> colour_off;<\/div>\n<\/div>\n<\/li>\n
  33. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* \u7a7a\u95f2\u5bf9\u8c61\u94fe\u8868\u653e\u5728\u5916\u90e8\u65f6\u4f7f\u7528\uff0c\u5176\u6307\u5411\u7684SLAB\u9ad8\u901f\u7f13\u5b58\u6765\u5b58\u50a8\u7a7a\u95f2\u5bf9\u8c61\u94fe\u8868 *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  34. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> kmem_cache<\/span> *freelist_cache<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
  35. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* \u7a7a\u95f2\u5bf9\u8c61\u94fe\u8868\u7684\u5927\u5c0f *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  36. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> int<\/span> freelist_size;<\/div>\n<\/div>\n<\/li>\n
  37. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  38. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* SLAB\u4e2d\u5b58\u653e\u7684\u5bf9\u8c61\u7684\u6784\u9020\u51fd\u6570*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  39. \n
    \n
    <\/div>\n<\/div>\n
    \n
    void<\/span> (*ctor)(void<\/span> *obj);<\/div>\n<\/div>\n<\/li>\n
  40. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  41. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* 4) cache creation\/removal *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  42. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u9ad8\u901f\u7f13\u5b58\u7684\u540d\u79f0*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  43. \n
    \n
    <\/div>\n<\/div>\n
    \n
    const<\/span> char<\/span> *name;<\/div>\n<\/div>\n<\/li>\n
  44. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u9ad8\u901f\u7f13\u5b58\u63cf\u8ff0\u7b26\u7684\u53cc\u5411\u94fe\u8868\u6307\u9488*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  45. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> list_head<\/span> list<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
  46. \n
    \n
    <\/div>\n<\/div>\n
    \n
    int<\/span> refcount;<\/div>\n<\/div>\n<\/li>\n
  47. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*SLAB\u4e2d\u5b58\u653e\u7684\u5bf9\u8c61\u7684\u5927\u5c0f*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  48. \n
    \n
    <\/div>\n<\/div>\n
    \n
    int<\/span> object_size;<\/div>\n<\/div>\n<\/li>\n
  49. \n
    \n
    <\/div>\n<\/div>\n
    \n
    int<\/span> align;<\/div>\n<\/div>\n<\/li>\n
  50. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  51. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/* 5) statistics *\/<\/span><\/div>\n<\/div>\n<\/li>\n
  52. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #ifdef<\/span> CONFIG_DEBUG_SLAB<\/span><\/div>\n<\/div>\n<\/li>\n
  53. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> num_active;<\/div>\n<\/div>\n<\/li>\n
  54. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> num_allocations;<\/div>\n<\/div>\n<\/li>\n
  55. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> high_mark;<\/div>\n<\/div>\n<\/li>\n
  56. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> grown;<\/div>\n<\/div>\n<\/li>\n
  57. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> reaped;<\/div>\n<\/div>\n<\/li>\n
  58. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> errors;<\/div>\n<\/div>\n<\/li>\n
  59. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> max_freeable;<\/div>\n<\/div>\n<\/li>\n
  60. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> node_allocs;<\/div>\n<\/div>\n<\/li>\n
  61. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> node_frees;<\/div>\n<\/div>\n<\/li>\n
  62. \n
    \n
    <\/div>\n<\/div>\n
    \n
    unsigned<\/span> long<\/span> node_overflow;<\/div>\n<\/div>\n<\/li>\n
  63. \n
    \n
    <\/div>\n<\/div>\n
    \n
    atomic_t<\/span> allochit;<\/div>\n<\/div>\n<\/li>\n
  64. \n
    \n
    <\/div>\n<\/div>\n
    \n
    atomic_t<\/span> allocmiss;<\/div>\n<\/div>\n<\/li>\n
  65. \n
    \n
    <\/div>\n<\/div>\n
    \n
    atomic_t<\/span> freehit;<\/div>\n<\/div>\n<\/li>\n
  66. \n
    \n
    <\/div>\n<\/div>\n
    \n
    atomic_t<\/span> freemiss;<\/div>\n<\/div>\n<\/li>\n
  67. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #ifdef<\/span> CONFIG_DEBUG_SLAB_LEAK<\/span><\/div>\n<\/div>\n<\/li>\n
  68. \n
    \n
    <\/div>\n<\/div>\n
    \n
    atomic_t<\/span> store_user_clean;<\/div>\n<\/div>\n<\/li>\n
  69. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
  70. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u5bf9\u8c61\u95f4\u7684\u504f\u79fb*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  71. \n
    \n
    <\/div>\n<\/div>\n
    \n
    int<\/span> obj_offset;<\/div>\n<\/div>\n<\/li>\n
  72. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #endif<\/span> \/* CONFIG_DEBUG_SLAB *\/<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
  73. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  74. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #ifdef<\/span> CONFIG_MEMCG<\/span><\/div>\n<\/div>\n<\/li>\n
  75. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> memcg_cache_params<\/span> memcg_params<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
  76. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
  77. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #ifdef<\/span> CONFIG_KASAN<\/span><\/div>\n<\/div>\n<\/li>\n
  78. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> kasan_cache<\/span> kasan_info<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
  79. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
  80. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  81. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #ifdef<\/span> CONFIG_SLAB_FREELIST_RANDOM<\/span><\/div>\n<\/div>\n<\/li>\n
  82. \n
    \n
    <\/div>\n<\/div>\n
    \n
    void<\/span> *random_seq;<\/div>\n<\/div>\n<\/li>\n
  83. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
  84. \n
    \n
    <\/div>\n<\/div>\n
    \n
    \/*\u4e00\u4e2a\u8282\u70b9\u9ad8\u901f\u7f13\u5b58\u7684\u6307\u9488\u6570\u7ec4\uff0c\u6570\u7ec4\u4e2d\u7684\u6bcf\u4e00\u4e2a\u5143\u7d20\u6307\u5411\u6bcf\u4e00\u4e2aNUMA\u8282\u70b9\u7684\u9ad8\u901f\u7f13\u5b58*\/<\/span><\/div>\n<\/div>\n<\/li>\n
  85. \n
    \n
    <\/div>\n<\/div>\n
    \n
    struct<\/span> kmem_cache_node<\/span> *node<\/span>[MAX_NUMNODES<\/span>];<\/span><\/div>\n<\/div>\n<\/li>\n
  86. \n
    \n
    <\/div>\n<\/div>\n
    \n
    };<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
    <\/code><\/pre>\n
    \u5728struct kmem_cache\u7ed3\u6784\u4f53\u4e2d\uff0cstruct array_cache __percpu *cpu_cache\u548cstruct kmem_cache_node\u00a0 *node[MAX_NUMNODES]\u8fd9\u4e24\u4e2a\u5c5e\u6027\u6bd4\u8f83\u91cd\u8981\u3002array_cache\u9488\u5bf9\u7684\u662f\u6bcf\u4e00\u4e2aCPU\u7684SLAB\u9ad8\u901f\u7f13\u5b58\uff0ckmem_cache_node\u662f\u9488\u5bf9\u6bcf\u4e00\u4e2aNUMA\u8282\u70b9\u7684SLAB\u9ad8\u901f\u7f13\u5b58\u3002\u5176\u4e2d\uff0cstruct kmem_cache_node\u7ed3\u6784\u4f53\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
    <\/code><\/pre>\n
      \n
    1. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*NUMA\u8282\u70b9\u9ad8\u901f\u7f13\u5b58*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    2. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> kmem_cache_node<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
    3. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u81ea\u65cb\u9501*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    4. \n
      \n
      <\/div>\n<\/div>\n
      \n
      spinlock_t<\/span> list_lock;<\/div>\n<\/div>\n<\/li>\n
    5. \n
      \n
      <\/div>\n<\/div>\n
      \n
      <\/div>\n<\/div>\n<\/li>\n
    6. \n
      \n
      <\/div>\n<\/div>\n
      \n
      #ifdef<\/span> CONFIG_SLAB<\/span><\/div>\n<\/div>\n<\/li>\n
    7. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u5305\u542b\u7a7a\u95f2\u5bf9\u8c61\u548c\u975e\u7a7a\u95f2\u5bf9\u8c61\u7684SLAB\u63cf\u8ff0\u7b26\u53cc\u5411\u5faa\u73af\u94fe\u8868*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    8. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> list_head<\/span> slabs_partial<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
    9. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u4e0d\u5305\u542b\u7a7a\u95f2\u5bf9\u8c61\u7684SLAB\u63cf\u8ff0\u7b26\u53cc\u5411\u5faa\u73af\u94fe\u8868*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    10. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> list_head<\/span> slabs_full<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
    11. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u53ea\u5305\u542b\u7a7a\u95f2\u5bf9\u8c61\u7684SLAB\u63cf\u8ff0\u7b26\u7684\u53cc\u5411\u5faa\u73af\u94fe\u8868*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    12. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> list_head<\/span> slabs_free<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
    13. \n
      \n
      <\/div>\n<\/div>\n
      \n
      <\/div>\n<\/div>\n<\/li>\n
    14. \n
      \n
      <\/div>\n<\/div>\n
      \n
      unsigned<\/span> long<\/span> free_objects;<\/div>\n<\/div>\n<\/li>\n
    15. \n
      \n
      <\/div>\n<\/div>\n
      \n
      unsigned<\/span> int<\/span> free_limit;<\/div>\n<\/div>\n<\/li>\n
    16. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u4e0b\u4e00\u4e2a\u88ab\u5206\u914d\u7684SLAB\u7684\u989c\u8272*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    17. \n
      \n
      <\/div>\n<\/div>\n
      \n
      unsigned<\/span> int<\/span> colour_next;<\/div>\n<\/div>\n<\/li>\n
    18. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u672cNUMA\u8282\u70b9\u5185\u88ab\u591a\u4e2aCPU\u6240\u5171\u4eab\u7684\u672c\u5730\u9ad8\u901f\u7f13\u5b58\u6307\u9488*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    19. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> array_cache<\/span> *shared<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
    20. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> alien_cache<\/span> **alien<\/span>;<\/span> \/* on other nodes *\/<\/span><\/div>\n<\/div>\n<\/li>\n
    21. \n
      \n
      <\/div>\n<\/div>\n
      \n
      \/*\u4e24\u6b21\u7f13\u5b58\u6536\u7f29\u65f6\u7684\u95f4\u9694*\/<\/span><\/div>\n<\/div>\n<\/li>\n
    22. \n
      \n
      <\/div>\n<\/div>\n
      \n
      unsigned<\/span> long<\/span> next_reap; \/* updated without locking *\/<\/span><\/div>\n<\/div>\n<\/li>\n
    23. \n
      \n
      <\/div>\n<\/div>\n
      \n
      int<\/span> free_touched; \/* updated without locking *\/<\/span><\/div>\n<\/div>\n<\/li>\n
    24. \n
      \n
      <\/div>\n<\/div>\n
      \n
      #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
    25. \n
      \n
      <\/div>\n<\/div>\n
      \n
      <\/div>\n<\/div>\n<\/li>\n
    26. \n
      \n
      <\/div>\n<\/div>\n
      \n
      #ifdef<\/span> CONFIG_SLUB<\/span><\/div>\n<\/div>\n<\/li>\n
    27. \n
      \n
      <\/div>\n<\/div>\n
      \n
      unsigned<\/span> long<\/span> nr_partial;<\/div>\n<\/div>\n<\/li>\n
    28. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> list_head<\/span> partial<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
    29. \n
      \n
      <\/div>\n<\/div>\n
      \n
      #ifdef<\/span> CONFIG_SLUB_DEBUG<\/span><\/div>\n<\/div>\n<\/li>\n
    30. \n
      \n
      <\/div>\n<\/div>\n
      \n
      atomic_long_t<\/span> nr_slabs;<\/div>\n<\/div>\n<\/li>\n
    31. \n
      \n
      <\/div>\n<\/div>\n
      \n
      atomic_long_t<\/span> total_objects;<\/div>\n<\/div>\n<\/li>\n
    32. \n
      \n
      <\/div>\n<\/div>\n
      \n
      struct<\/span> list_head<\/span> full<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
    33. \n
      \n
      <\/div>\n<\/div>\n
      \n
      #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
    34. \n
      \n
      <\/div>\n<\/div>\n
      \n
      #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
    35. \n
      \n
      <\/div>\n<\/div>\n
      \n
      };<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
      <\/code><\/pre>\n
      \u5728struct kmem_cache_node\u7ed3\u6784\u4f53\u4e2d\uff0c\u6709\u4e09\u4e2a\u6bd4\u8f83\u91cd\u8981\u7684\u5c5e\u6027\uff1aslabs_partial\u3001slabs_full\u3001slabs_free\uff0c\u5176\u4e2dslabs_partial\u6307\u5411\u53ea\u6709\u90e8\u5206\u5bf9\u8c61\u88ab\u4f7f\u7528\u7684slab\u7684\u63cf\u8ff0\u7b26\u7684\u94fe\u8868\uff0cslabs_full\u6307\u5411\u6240\u6709\u5bf9\u8c61\u90fd\u88ab\u4f7f\u7528\u7684slab\u7684\u63cf\u8ff0\u7b26\u7684\u94fe\u8868\uff0cslabs_free\u6307\u5411\u6240\u6709\u5bf9\u8c61\u90fd\u6ca1\u6709\u88ab\u4f7f\u7528\u7684slab\u7684\u63cf\u8ff0\u7b26\u7684\u94fe\u8868\u3002<\/p>\n
      \u6709\u5173slab\u7684\u63cf\u8ff0\u7b26\uff0c\u5176\u5b9a\u4e49\u662f\u5728struct page\u4e2d\uff0c\u76f8\u5173\u4ee3\u7801\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
      <\/code><\/pre>\n
        \n
      1. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> page<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
      2. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* First double word block *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      3. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*\u9875\u63cf\u8ff0\u7b26\u76f8\u5173\u5b57\u6bb5\uff0c\u4e0e\u9875\u6846\u6709\u5173\u7684\u4e00\u7ec4\u6807\u5fd7*\/<\/span><\/div>\n<\/div>\n<\/li>\n
      4. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> long<\/span> flags;<\/div>\n<\/div>\n<\/li>\n
      5. \n
        \n
        <\/div>\n<\/div>\n
        \n
        union<\/span> {<\/div>\n<\/div>\n<\/li>\n
      6. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*\u9875\u63cf\u8ff0\u7b26\u76f8\u5173\u5b57\u6bb5*\/<\/span><\/div>\n<\/div>\n<\/li>\n
      7. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> address_space<\/span> *mapping<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
      8. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*\u4e0eSLAB\u63cf\u8ff0\u7b26\u6709\u5173\uff0c\u6307\u5411SLAB\u4e2d\u7b2c\u4e00\u4e2a\u5bf9\u8c61\u7684\u5730\u5740*\/<\/span><\/div>\n<\/div>\n<\/li>\n
      9. \n
        \n
        <\/div>\n<\/div>\n
        \n
        void<\/span> *s_mem; \/* slab first object *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      10. \n
        \n
        <\/div>\n<\/div>\n
        \n
        atomic_t<\/span> compound_mapcount; \/* first tail page *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      11. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* page_deferred_list().next — second tail page *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      12. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      13. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      14. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* Second double word *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      15. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
      16. \n
        \n
        <\/div>\n<\/div>\n
        \n
        union<\/span> {<\/div>\n<\/div>\n<\/li>\n
      17. \n
        \n
        <\/div>\n<\/div>\n
        \n
        pgoff_t<\/span> index; \/* Our offset within mapping. *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      18. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*\u4e0eSLAB\u63cf\u8ff0\u7b26\u76f8\u5173\uff0c\u6307\u5411SLAB\u4e2d\u7a7a\u95f2\u5bf9\u8c61\u94fe\u8868*\/<\/span><\/div>\n<\/div>\n<\/li>\n
      19. \n
        \n
        <\/div>\n<\/div>\n
        \n
        void<\/span> *freelist; \/* sl[aou]b first free object *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      20. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* page_deferred_list().prev — second tail page *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      21. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      22. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      23. \n
        \n
        <\/div>\n<\/div>\n
        \n
        union<\/span> {<\/div>\n<\/div>\n<\/li>\n
      24. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #if<\/span> defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \\<\/span><\/div>\n<\/div>\n<\/li>\n
      25. \n
        \n
        <\/div>\n<\/div>\n
        \n
         defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE)<\/span><\/div>\n<\/div>\n<\/li>\n
      26. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* Used for cmpxchg_double in slub *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      27. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> long<\/span> counters;<\/div>\n<\/div>\n<\/li>\n
      28. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #else<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      29. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> counters;<\/div>\n<\/div>\n<\/li>\n
      30. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      31. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      32. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
      33. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      34. \n
        \n
        <\/div>\n<\/div>\n
        \n
        union<\/span> {<\/div>\n<\/div>\n<\/li>\n
      35. \n
        \n
        <\/div>\n<\/div>\n
        \n
        atomic_t<\/span> _mapcount;<\/div>\n<\/div>\n<\/li>\n
      36. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      37. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> {<\/span> \/* SLUB *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      38. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> inuse:16<\/span>;<\/div>\n<\/div>\n<\/li>\n
      39. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> objects:15<\/span>;<\/div>\n<\/div>\n<\/li>\n
      40. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> frozen:1<\/span>;<\/div>\n<\/div>\n<\/li>\n
      41. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      42. \n
        \n
        <\/div>\n<\/div>\n
        \n
        int<\/span> units; \/* SLOB *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      43. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      44. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
      45. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * Usage count, *USE WRAPPER FUNCTION*<\/span><\/div>\n<\/div>\n<\/li>\n
      46. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * when manual accounting. See page_ref.h<\/span><\/div>\n<\/div>\n<\/li>\n
      47. \n
        \n
        <\/div>\n<\/div>\n
        \n
         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      48. \n
        \n
        <\/div>\n<\/div>\n
        \n
        atomic_t<\/span> _refcount;<\/div>\n<\/div>\n<\/li>\n
      49. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      50. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> int<\/span> active; \/* SLAB *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      51. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      52. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      53. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      54. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
      55. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * Third double word block<\/span><\/div>\n<\/div>\n<\/li>\n
      56. \n
        \n
        <\/div>\n<\/div>\n
        \n
         *<\/span><\/div>\n<\/div>\n<\/li>\n
      57. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * WARNING: bit 0 of the first word encode PageTail(). That means<\/span><\/div>\n<\/div>\n<\/li>\n
      58. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * the rest users of the storage space MUST NOT use the bit to<\/span><\/div>\n<\/div>\n<\/li>\n
      59. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * avoid collision and false-positive PageTail().<\/span><\/div>\n<\/div>\n<\/li>\n
      60. \n
        \n
        <\/div>\n<\/div>\n
        \n
         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      61. \n
        \n
        <\/div>\n<\/div>\n
        \n
        union<\/span> {<\/div>\n<\/div>\n<\/li>\n
      62. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*\u6709\u591a\u91cd\u7528\u9014\uff0c\u5728SLAB\u4e2d\u8868\u793a\u52a0\u5165\u5230kmem_cache\u4e2d\u7684SLAB\u63cf\u8ff0\u7b26\u94fe\u8868\u4e2d*\/<\/span><\/div>\n<\/div>\n<\/li>\n
      63. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> list_head<\/span> lru<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
      64. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> dev_pagemap<\/span> *pgmap<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
      65. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> {<\/span> \/* slub per cpu partial pages *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      66. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> page<\/span> *next<\/span>;<\/span> \/* Next partial slab *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      67. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #ifdef<\/span> CONFIG_64BIT<\/span><\/div>\n<\/div>\n<\/li>\n
      68. \n
        \n
        <\/div>\n<\/div>\n
        \n
        int<\/span> pages; \/* Nr of partial slabs left *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      69. \n
        \n
        <\/div>\n<\/div>\n
        \n
        int<\/span> pobjects; \/* Approximate # of objects *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      70. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #else<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      71. \n
        \n
        <\/div>\n<\/div>\n
        \n
        short<\/span> int<\/span> pages;<\/div>\n<\/div>\n<\/li>\n
      72. \n
        \n
        <\/div>\n<\/div>\n
        \n
        short<\/span> int<\/span> pobjects;<\/div>\n<\/div>\n<\/li>\n
      73. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      74. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      75. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      76. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> rcu_head<\/span> rcu_head<\/span>;<\/span> \/* Used by SLAB<\/span><\/div>\n<\/div>\n<\/li>\n
      77. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * when destroying via RCU<\/span><\/div>\n<\/div>\n<\/li>\n
      78. \n
        \n
        <\/div>\n<\/div>\n
        \n
         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      79. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* Tail pages of compound page *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      80. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
      81. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> long<\/span> compound_head; \/* If bit zero is set *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      82. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      83. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* First tail page only *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      84. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #ifdef<\/span> CONFIG_64BIT<\/span><\/div>\n<\/div>\n<\/li>\n
      85. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> int<\/span> compound_dtor;<\/div>\n<\/div>\n<\/li>\n
      86. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> int<\/span> compound_order;<\/div>\n<\/div>\n<\/li>\n
      87. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #else<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      88. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> short<\/span> int<\/span> compound_dtor;<\/div>\n<\/div>\n<\/li>\n
      89. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> short<\/span> int<\/span> compound_order;<\/div>\n<\/div>\n<\/li>\n
      90. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      91. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      92. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      93. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #if<\/span> defined(CONFIG_TRANSPARENT_HUGEPAGE) && USE_SPLIT_PMD_PTLOCKS<\/span><\/div>\n<\/div>\n<\/li>\n
      94. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
      95. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> long<\/span> __pad;<\/div>\n<\/div>\n<\/li>\n
      96. \n
        \n
        <\/div>\n<\/div>\n
        \n
        pgtable_t<\/span> pmd_huge_pte; \/* protected by page->ptl *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      97. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      98. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      99. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      100. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      101. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/* Remainder is not double word aligned *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      102. \n
        \n
        <\/div>\n<\/div>\n
        \n
        union<\/span> {<\/div>\n<\/div>\n<\/li>\n
      103. \n
        \n
        <\/div>\n<\/div>\n
        \n
        unsigned<\/span> long<\/span> private<\/span>;<\/div>\n<\/div>\n<\/li>\n
      104. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #if<\/span> USE_SPLIT_PTE_PTLOCKS<\/span><\/div>\n<\/div>\n<\/li>\n
      105. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #if<\/span> ALLOC_SPLIT_PTLOCKS<\/span><\/div>\n<\/div>\n<\/li>\n
      106. \n
        \n
        <\/div>\n<\/div>\n
        \n
        spinlock_t<\/span> *ptl;<\/div>\n<\/div>\n<\/li>\n
      107. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #else<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      108. \n
        \n
        <\/div>\n<\/div>\n
        \n
        spinlock_t<\/span> ptl;<\/div>\n<\/div>\n<\/li>\n
      109. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      110. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      111. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> kmem_cache<\/span> *slab_cache<\/span>;<\/span> \/* SL[AU]B: Pointer to slab *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      112. \n
        \n
        <\/div>\n<\/div>\n
        \n
        };<\/div>\n<\/div>\n<\/li>\n
      113. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      114. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #ifdef<\/span> CONFIG_MEMCG<\/span><\/div>\n<\/div>\n<\/li>\n
      115. \n
        \n
        <\/div>\n<\/div>\n
        \n
        struct<\/span> mem_cgroup<\/span> *mem_cgroup<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
      116. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      117. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      118. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #if<\/span> defined(WANT_PAGE_VIRTUAL)<\/span><\/div>\n<\/div>\n<\/li>\n
      119. \n
        \n
        <\/div>\n<\/div>\n
        \n
        void<\/span> *virtual<\/span>; \/* Kernel virtual address (NULL if<\/span><\/div>\n<\/div>\n<\/li>\n
      120. \n
        \n
        <\/div>\n<\/div>\n
        \n
         not kmapped, ie. highmem) *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      121. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span> \/* WANT_PAGE_VIRTUAL *\/<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      122. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      123. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #ifdef<\/span> CONFIG_KMEMCHECK<\/span><\/div>\n<\/div>\n<\/li>\n
      124. \n
        \n
        <\/div>\n<\/div>\n
        \n
        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
      125. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * kmemcheck wants to track the status of each byte in a page; this<\/span><\/div>\n<\/div>\n<\/li>\n
      126. \n
        \n
        <\/div>\n<\/div>\n
        \n
         * is a pointer to such a status block. NULL if not tracked.<\/span><\/div>\n<\/div>\n<\/li>\n
      127. \n
        \n
        <\/div>\n<\/div>\n
        \n
         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
      128. \n
        \n
        <\/div>\n<\/div>\n
        \n
        void<\/span> *shadow;<\/div>\n<\/div>\n<\/li>\n
      129. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      130. \n
        \n
        <\/div>\n<\/div>\n
        \n
        <\/div>\n<\/div>\n<\/li>\n
      131. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #ifdef<\/span> LAST_CPUPID_NOT_IN_PAGE_FLAGS<\/span><\/div>\n<\/div>\n<\/li>\n
      132. \n
        \n
        <\/div>\n<\/div>\n
        \n
        int<\/span> _last_cpupid;<\/div>\n<\/div>\n<\/li>\n
      133. \n
        \n
        <\/div>\n<\/div>\n
        \n
        #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
      134. \n
        \n
        <\/div>\n<\/div>\n
        \n
        }<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
        <\/code><\/pre>\n
        \u5728struct page\u7ed3\u6784\u4f53\u4e2d\uff0c\u4e0eSLAB\u6709\u5173\u7684\u6bd4\u8f83\u91cd\u8981\u7684\u4e24\u4e2a\u5c5e\u6027\uff1as_mem\u548cfreelist\uff0c\u5176\u4e2ds_mem\u6307\u5411slab\u4e2d\u7684\u7b2c\u4e00\u4e2a\u5bf9\u8c61\u7684\u5730\u5740\uff08\u6216\u8005\u5df2\u7ecf\u88ab\u5206\u914d\u6216\u8005\u7a7a\u95f2\uff09\u3002freelist\u6307\u5411\u7a7a\u95f2\u5bf9\u8c61\u94fe\u8868\u3002<\/p>\n
        \u5728struct kmem_cache\u7ed3\u6784\u4f53\u4e2d\u6709\u4e00\u4e2a\u5c5e\u6027cpu_cache\uff0ccpu_cache\u662f\u4e00\u4e2a\u6307\u5411\u6570\u7ec4\u7684\u6307\u9488\uff0c\u6bcf\u4e2a\u6570\u7ec4\u9879\u90fd\u5bf9\u5e94\u7cfb\u7edf\u4e2d\u7684\u4e00\u4e2aCPU\uff0c\u6bcf\u4e2a\u6570\u7ec4\u9879\u90fd\u5305\u542b\u4e86\u4e00\u4e2a\u6307\u5411struct array_cache\u7684\u6307\u9488,\u5176\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
        <\/code><\/pre>\n
          \n
        1. \n
          \n
          <\/div>\n<\/div>\n
          \n
          struct<\/span> array_cache<\/span> {<\/span><\/div>\n<\/div>\n<\/li>\n
        2. \n
          \n
          <\/div>\n<\/div>\n
          \n
          \/*\u4fdd\u5b58\u4e86per-CPU\u7f13\u5b58\u4e2d\u53ef\u4f7f\u7528\u5bf9\u8c61\u7684\u6307\u9488\u7684\u4e2a\u6570*\/<\/span><\/div>\n<\/div>\n<\/li>\n
        3. \n
          \n
          <\/div>\n<\/div>\n
          \n
          unsigned<\/span> int<\/span> avail;<\/div>\n<\/div>\n<\/li>\n
        4. \n
          \n
          <\/div>\n<\/div>\n
          \n
          \/*\u4fdd\u5b58\u7684\u5bf9\u8c61\u7684\u6700\u5927\u7684\u6570\u91cf*\/<\/span><\/div>\n<\/div>\n<\/li>\n
        5. \n
          \n
          <\/div>\n<\/div>\n
          \n
          unsigned<\/span> int<\/span> limit;<\/div>\n<\/div>\n<\/li>\n
        6. \n
          \n
          <\/div>\n<\/div>\n
          \n
          \/*\u5982\u679cper-CPU\u5217\u8868\u4e2d\u4fdd\u5b58\u7684\u6700\u5927\u5bf9\u8c61\u7684\u6570\u76ee\u8d85\u8fc7limit\u503c\uff0c\u5185\u6838\u4f1a\u5c06batchcount\u4e2a\u5bf9\u8c61\u8fd4\u56de\u5230slab*\/<\/span><\/div>\n<\/div>\n<\/li>\n
        7. \n
          \n
          <\/div>\n<\/div>\n
          \n
          unsigned<\/span> int<\/span> batchcount;<\/div>\n<\/div>\n<\/li>\n
        8. \n
          \n
          <\/div>\n<\/div>\n
          \n
          \/*\u4eceper\u2014CPU\u7f13\u5b58\u4e2d\u79fb\u9664\u4e00\u4e2a\u5bf9\u8c61\u65f6\uff0c\u6b64\u503c\u5c06\u88ab\u8bbe\u7f6e\u4e3a1\uff0c\u7f13\u5b58\u6536\u7f29\u65f6\uff0c\u6b64\u65f6\u88ab\u8bbe\u7f6e\u4e3a0.\u8fd9\u4f7f\u5f97\u5185\u6838\u80fd\u591f\u786e\u8ba4\u5728\u7f13\u5b58\u4e0a\u4e00\u6b21<\/span><\/div>\n<\/div>\n<\/li>\n
        9. \n
          \n
          <\/div>\n<\/div>\n
          \n
           \u6536\u7f29\u4e4b\u540e\u662f\u5426\u88ab\u8bbf\u95ee\u8fc7\uff0c\u4e5f\u662f\u7f13\u5b58\u91cd\u8981\u6027\u7684\u4e00\u4e2a\u6807\u5fd7*\/<\/span><\/div>\n<\/div>\n<\/li>\n
        10. \n
          \n
          <\/div>\n<\/div>\n
          \n
          unsigned<\/span> int<\/span> touched;<\/div>\n<\/div>\n<\/li>\n
        11. \n
          \n
          <\/div>\n<\/div>\n
          \n
          \/*\u4e00\u4e2a\u4f2a\u6307\u9488\u6570\u7ec4\uff0c\u6307\u5411per-CPU\u7f13\u5b58\u7684\u5bf9\u8c61*\/<\/span><\/div>\n<\/div>\n<\/li>\n
        12. \n
          \n
          <\/div>\n<\/div>\n
          \n
          void<\/span> *entry[];<\/div>\n<\/div>\n<\/li>\n
        13. \n
          \n
          <\/div>\n<\/div>\n
          \n
          };<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
          <\/code><\/pre>\n
          \u8bf4\u4e86\u8fd9\u4e48\u591a\uff0c\u4f60\u53ef\u80fd\u4e0d\u592a\u6e05\u695a\u4e0a\u9762\u7684\u8fd9\u4e9b\u7ed3\u6784\u4f53\u5230\u5e95\u90fd\u4ec0\u4e48\u5173\u7cfb\u3002\u4e3a\u4e86\u66f4\u597d\u7684\u7406\u89e3\u4e0a\u9762\u8fd9\u4e9b\u7ed3\u6784\u4f53\u4e4b\u95f4\u7684\u5173\u7cfb\uff0c\u8bf7\u770b\u4e0b\u9762\u7684\u8fd9\u5e45\u56fe\uff1a<\/p>\n
          \"\"<\/p>\n
          \u5177\u4f53\u7684\u6d41\u7a0b\u53ef\u4ee5\u53c2\u8003\u535a\u5ba2\uff1ahttps:\/\/blog.csdn.net\/lukuen\/article\/details\/6935068<\/a>\uff0c\u8bf7\u8bfb\u8005\u4e00\u5b9a\u8981\u770b\u4e00\u4e0b\u8fd9\u7bc7\u535a\u5ba2\u3002<\/p>\n
          3.3 SLAB\u4e0e\u5206\u533a\u9875\u6846\u5206\u914d\u5668<\/p>\n
          \u5148\u4ecb\u7ecd\u4e00\u4e0b\u5206\u533a\u9875\u6846\u5206\u914d\u5668\uff0c\u5206\u533a\u9875\u6846\u5206\u914d\u5668\u7528\u4e8e\u5904\u7406\u5bf9\u8fde\u7eed\u9875\u6846\u7ec4\u7684\u5185\u5b58\u5206\u914d\u8bf7\u6c42\u3002\u5176\u4e2d\u6709\u4e00\u4e9b\u51fd\u6570\u548c\u5b8f\u8bf7\u6c42\u9875\u6846\uff0c\u4e00\u822c\u60c5\u51b5\u4e0b\uff0c\u5b83\u4eec\u90fd\u8fd4\u56de\u7b2c\u4e00\u4e2a\u6240\u5206\u914d\u7684\u9875\u7684\u7ebf\u6027\u5730\u5740\uff0c\u5982\u679c\u5206\u914d\u5931\u8d25\uff0c\u5219\u8fd4\u56deNULL\u3002\u8fd9\u4e9b\u51fd\u6570\u7b80\u4ecb\u5982\u4e0b\uff1a<\/p>\n
          <\/code><\/pre>\n
            \n
          1. \n
            \n
            <\/div>\n<\/div>\n
            \n
            alloc_pages<\/span>(gfp_mask,order)\uff1a\u8bf7\u6c422<\/span>^order<\/span>\u4e2a\u8fde\u7eed\u7684\u9875\u6846\uff0c\u4ed6\u8fd4\u56de\u7b2c\u4e00\u4e2a\u6240\u5206\u914d\u9875\u6846\u7684\u63cf\u8ff0\u7b26\u7684\u5730\u5740\u3002\u5206\u914d\u5931\u8d25\u5219\u8fd4\u56deNULL<\/span>\u3002<\/div>\n<\/div>\n<\/li>\n
          2. \n
            \n
            <\/div>\n<\/div>\n
            \n
            <\/div>\n<\/div>\n<\/li>\n
          3. \n
            \n
            <\/div>\n<\/div>\n
            \n
            __get_free_pages<\/span>(gfp_mask,order)\uff1a\u4e0e\u51fd\u6570alloc_pages<\/span>(gfp_mask,orser)\u7c7b\u4f3c\uff0c\u4f46\u662f\u6b64\u51fd\u6570\u8fd4\u56de\u7b2c\u4e00\u4e2a\u6240\u5206\u914d\u9875\u7684\u7ebf\u6027\u5730\u5740\u3002<\/div>\n<\/div>\n<\/li>\n
          4. \n
            \n
            <\/div>\n<\/div>\n
            \n
            <\/div>\n<\/div>\n<\/li>\n
          5. \n
            \n
            <\/div>\n<\/div>\n
            \n
            __free_pages<\/span>(page,order)\uff1a\u8be5\u51fd\u6570\u5148\u68c0\u67e5page<\/span>\u6307\u5411\u7684\u9875\u63cf\u8ff0\u7b26\uff0c\u5982\u679c\u8be5\u9875\u6846\u672a\u88ab\u4fdd\u7559(PG_reserved\u6807\u5fd7\u4f4d\u4e3a<\/div>\n<\/div>\n<\/li>\n
          6. \n
            \n
            <\/div>\n<\/div>\n
            \n
            0<\/span>)\uff0c\u5c31\u628a\u63cf\u8ff0\u7b26\u7684count<\/span>\u5b57\u6bb5\u503c\u51cf1<\/span>\u3002\u5982\u679ccount<\/span>\u5b57\u6bb5\u7684\u503c\u53d8\u4e3a0<\/span>\uff0c\u5c31\u5047\u5b9a\u4ece\u4e0epage<\/span>\u5bf9\u5e94\u7684\u9875\u6846\u5f00\u59cb\u76842<\/span>^order<\/span>\u4e2a\u8fde\u7eed\u7684\u9875\u6846\u4e0d\u518d\u88ab\u4f7f\u7528\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\u8be5\u51fd\u6570\u91ca\u653e\u9875\u6846\u3002<\/div>\n<\/div>\n<\/li>\n
          7. \n
            \n
            <\/div>\n<\/div>\n
            \n
            <\/div>\n<\/div>\n<\/li>\n
          8. \n
            \n
            <\/div>\n<\/div>\n
            \n
            free_pages<\/span>(addr,order)\uff1a\u7c7b\u4f3c\u4e8e__free_pages<\/span>()\uff0c\u4f46\u662f\u5b83\u63a5\u6536\u7684\u53c2\u6570\u4e3a\u8981\u91ca\u653e\u7684\u7b2c\u4e00\u4e2a\u9875\u6846\u7684\u7ebf\u6027\u5730\u5740addr<\/span>\u3002<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
            <\/code><\/pre>\n
            \u5f53SLAB\u5206\u914d\u5668\u521b\u5efa\u65b0\u7684SLAB\u65f6\uff0c\u9700\u8981\u4f9d\u9760\u5206\u533a\u9875\u6846\u5206\u914d\u5668\u6765\u83b7\u5f97\u4e00\u7ec4\u8fde\u7eed\u7684\u7a7a\u95f2\u9875\u6846\u3002\u4e3a\u4e86\u8fbe\u5230\u6b64\u76ee\u7684\uff0c\u9700\u8981\u8c03\u7528kmem_getpages()\u51fd\u6570\uff0c\u51fd\u6570\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
            static<\/span> struct page *kmem_getpages<\/span>(struct kmem_cache *cachep, gfp_t<\/span> flags,int<\/span> nodeid)<\/span><\/span><\/code><\/pre>\n
            static<\/span> void<\/span> kmem_freepages<\/span>(struct kmem_cache *cachep, struct page *page)<\/span><\/span><\/code><\/pre>\n
            3.4 SLAB\u4e0e\u9ad8\u901f\u7f13\u5b58<\/p>\n
            <\/code><\/pre>\n
              \n
            1. \n
              \n
              <\/div>\n<\/div>\n
              \n
              \/*<\/span><\/div>\n<\/div>\n<\/li>\n
            2. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * kmem_cache_create – Create a cache.<\/span><\/div>\n<\/div>\n<\/li>\n
            3. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * @name: A string which is used in \/proc\/slabinfo to identify this cache.<\/span><\/div>\n<\/div>\n<\/li>\n
            4. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * @size: The size of objects to be created in this cache.<\/span><\/div>\n<\/div>\n<\/li>\n
            5. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * @align: The required alignment for the objects.<\/span><\/div>\n<\/div>\n<\/li>\n
            6. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * @flags: SLAB flags<\/span><\/div>\n<\/div>\n<\/li>\n
            7. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * @ctor: A constructor for the objects.<\/span><\/div>\n<\/div>\n<\/li>\n
            8. \n
              \n
              <\/div>\n<\/div>\n
              \n
               *<\/span><\/div>\n<\/div>\n<\/li>\n
            9. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * Returns a ptr to the cache on success, NULL on failure.<\/span><\/div>\n<\/div>\n<\/li>\n
            10. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * Cannot be called within a interrupt, but can be interrupted.<\/span><\/div>\n<\/div>\n<\/li>\n
            11. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * The @ctor is run when new pages are allocated by the cache.<\/span><\/div>\n<\/div>\n<\/li>\n
            12. \n
              \n
              <\/div>\n<\/div>\n
              \n
               *<\/span><\/div>\n<\/div>\n<\/li>\n
            13. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * The flags are<\/span><\/div>\n<\/div>\n<\/li>\n
            14. \n
              \n
              <\/div>\n<\/div>\n
              \n
               *<\/span><\/div>\n<\/div>\n<\/li>\n
            15. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * %SLAB_POISON – Poison the slab with a known test pattern (a5a5a5a5)<\/span><\/div>\n<\/div>\n<\/li>\n
            16. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * to catch references to uninitialised memory.<\/span><\/div>\n<\/div>\n<\/li>\n
            17. \n
              \n
              <\/div>\n<\/div>\n
              \n
               *<\/span><\/div>\n<\/div>\n<\/li>\n
            18. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * %SLAB_RED_ZONE – Insert `Red’ zones around the allocated memory to check<\/span><\/div>\n<\/div>\n<\/li>\n
            19. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * for buffer overruns.<\/span><\/div>\n<\/div>\n<\/li>\n
            20. \n
              \n
              <\/div>\n<\/div>\n
              \n
               *<\/span><\/div>\n<\/div>\n<\/li>\n
            21. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * %SLAB_HWCACHE_ALIGN – Align the objects in this cache to a hardware<\/span><\/div>\n<\/div>\n<\/li>\n
            22. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * cacheline. This can be beneficial if you’re counting cycles as closely<\/span><\/div>\n<\/div>\n<\/li>\n
            23. \n
              \n
              <\/div>\n<\/div>\n
              \n
               * as davem.<\/span><\/div>\n<\/div>\n<\/li>\n
            24. \n
              \n
              <\/div>\n<\/div>\n
              \n
               *\/<\/span><\/div>\n<\/div>\n<\/li>\n
            25. \n
              \n
              <\/div>\n<\/div>\n
              \n
              struct<\/span> kmem_cache *kmem_cache_create(const<\/span> char<\/span> *name, size_t size, size_t align,<\/div>\n<\/div>\n<\/li>\n
            26. \n
              \n
              <\/div>\n<\/div>\n
              \n
              unsigned long<\/span> flags, void<\/span> (*ctor)(void<\/span> *));<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
              <\/code><\/pre>\n
              kmem_cache_create()\u51fd\u6570\u5728\u8c03\u7528\u6210\u529f\u65f6\u8fd4\u56de\u4e00\u4e2a\u6307\u5411\u6240\u6784\u9020\u7684\u9ad8\u901f\u7f13\u5b58\u7684\u6307\u9488\uff0c\u5931\u8d25\u5219\u8fd4\u56deNULL\u3002<\/p>\n
              \u4e0ekmem_cache_create()\u51fd\u6570\u76f8\u5bf9\u5e94\u7684\u662f\u9500\u6bc1\u9ad8\u901f\u7f13\u5b58\u7684\u51fd\u6570kmem_cache_destroy()\uff0c\u8be5\u51fd\u6570\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
              <\/code><\/pre>\n
                \n
              1. \n
                \n
                <\/div>\n<\/div>\n
                \n
                void<\/span> kmem_cache_destroy<\/span>(struct kmem_cache *s)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
              2. \n
                \n
                <\/div>\n<\/div>\n
                \n
                {<\/div>\n<\/div>\n<\/li>\n
              3. \n
                \n
                <\/div>\n<\/div>\n
                \n
                LIST_HEAD(release);<\/div>\n<\/div>\n<\/li>\n
              4. \n
                \n
                <\/div>\n<\/div>\n
                \n
                bool<\/span> need_rcu_barrier = false<\/span>;<\/div>\n<\/div>\n<\/li>\n
              5. \n
                \n
                <\/div>\n<\/div>\n
                \n
                int<\/span> err;<\/div>\n<\/div>\n<\/li>\n
              6. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              7. \n
                \n
                <\/div>\n<\/div>\n
                \n
                if<\/span> (unlikely(!s))<\/div>\n<\/div>\n<\/li>\n
              8. \n
                \n
                <\/div>\n<\/div>\n
                \n
                return<\/span>;<\/div>\n<\/div>\n<\/li>\n
              9. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              10. \n
                \n
                <\/div>\n<\/div>\n
                \n
                get_online_cpus();<\/div>\n<\/div>\n<\/li>\n
              11. \n
                \n
                <\/div>\n<\/div>\n
                \n
                get_online_mems();<\/div>\n<\/div>\n<\/li>\n
              12. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              13. \n
                \n
                <\/div>\n<\/div>\n
                \n
                kasan_cache_destroy(s);<\/div>\n<\/div>\n<\/li>\n
              14. \n
                \n
                <\/div>\n<\/div>\n
                \n
                mutex_lock(&slab_mutex);<\/div>\n<\/div>\n<\/li>\n
              15. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              16. \n
                \n
                <\/div>\n<\/div>\n
                \n
                s->refcount–;<\/div>\n<\/div>\n<\/li>\n
              17. \n
                \n
                <\/div>\n<\/div>\n
                \n
                if<\/span> (s->refcount)<\/div>\n<\/div>\n<\/li>\n
              18. \n
                \n
                <\/div>\n<\/div>\n
                \n
                goto<\/span> out_unlock;<\/div>\n<\/div>\n<\/li>\n
              19. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              20. \n
                \n
                <\/div>\n<\/div>\n
                \n
                err = shutdown_memcg_caches(s, &release, &need_rcu_barrier);<\/div>\n<\/div>\n<\/li>\n
              21. \n
                \n
                <\/div>\n<\/div>\n
                \n
                if<\/span> (!err)<\/div>\n<\/div>\n<\/li>\n
              22. \n
                \n
                <\/div>\n<\/div>\n
                \n
                err = shutdown_cache(s, &release, &need_rcu_barrier);<\/div>\n<\/div>\n<\/li>\n
              23. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              24. \n
                \n
                <\/div>\n<\/div>\n
                \n
                if<\/span> (err) {<\/div>\n<\/div>\n<\/li>\n
              25. \n
                \n
                <\/div>\n<\/div>\n
                \n
                pr_err(“kmem_cache_destroy %s: Slab cache still has objects\\n”<\/span>,<\/div>\n<\/div>\n<\/li>\n
              26. \n
                \n
                <\/div>\n<\/div>\n
                \n
                s->name);<\/div>\n<\/div>\n<\/li>\n
              27. \n
                \n
                <\/div>\n<\/div>\n
                \n
                dump_stack();<\/div>\n<\/div>\n<\/li>\n
              28. \n
                \n
                <\/div>\n<\/div>\n
                \n
                }<\/div>\n<\/div>\n<\/li>\n
              29. \n
                \n
                <\/div>\n<\/div>\n
                \n
                out_unlock:<\/div>\n<\/div>\n<\/li>\n
              30. \n
                \n
                <\/div>\n<\/div>\n
                \n
                mutex_unlock(&slab_mutex);<\/div>\n<\/div>\n<\/li>\n
              31. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              32. \n
                \n
                <\/div>\n<\/div>\n
                \n
                put_online_mems();<\/div>\n<\/div>\n<\/li>\n
              33. \n
                \n
                <\/div>\n<\/div>\n
                \n
                put_online_cpus();<\/div>\n<\/div>\n<\/li>\n
              34. \n
                \n
                <\/div>\n<\/div>\n
                \n
                <\/div>\n<\/div>\n<\/li>\n
              35. \n
                \n
                <\/div>\n<\/div>\n
                \n
                release_caches(&release, need_rcu_barrier);<\/div>\n<\/div>\n<\/li>\n
              36. \n
                \n
                <\/div>\n<\/div>\n
                \n
                }<\/div>\n<\/div>\n<\/li>\n
              37. \n
                \n
                <\/div>\n<\/div>\n
                \n
                EXPORT_SYMBOL(kmem_cache_destroy);<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                <\/code><\/pre>\n
                \u9700\u8981\u6ce8\u610f\u7684\u662f\uff1akmem_cache_destroy()\u51fd\u6570\u9500\u6bc1\u7684\u9ad8\u901f\u7f13\u5b58\u4e2d\u5e94\u8be5\u53ea\u5305\u542b\u672a\u4f7f\u7528\u5bf9\u8c61\uff0c\u5982\u679c\u4e00\u4e2a\u9ad8\u901f\u7f13\u5b58\u4e2d\u542b\u6709\u6b63\u5728\u4f7f\u7528\u7684\u5bf9\u8c61\u65f6\u8c03\u7528kmem_cache_destroy()\u51fd\u6570\u5c06\u4f1a\u5931\u8d25\uff0c\u4ecekmem_cache_destroy()\u51fd\u6570\u7684\u6e90\u4ee3\u7801\u4e2d\u6211\u4eec\u5f88\u5bb9\u6613\u770b\u51fa\u3002<\/p>\n
                \u4e0b\u9762\u770b\u4e00\u4e2a\u6709\u5173\u8fd9\u4e24\u4e2a\u51fd\u6570\u4f7f\u7528\u7684\u793a\u4f8b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
                <\/code><\/pre>\n
                  \n
                1. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  #define<\/span> KSM_KMEM_CACHE(__struct, __flags) kmem_cache_create(“ksm_”<\/span>#__struct,\\<\/span><\/div>\n<\/div>\n<\/li>\n
                2. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                   sizeof(struct __struct), __alignof__(struct __struct),\\<\/span><\/div>\n<\/div>\n<\/li>\n
                3. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                   (__flags), NULL)<\/span><\/div>\n<\/div>\n<\/li>\n
                4. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  <\/div>\n<\/div>\n<\/li>\n
                5. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  static<\/span> int<\/span> __init ksm_slab_init<\/span>(void<\/span>)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                6. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  {<\/div>\n<\/div>\n<\/li>\n
                7. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  rmap_item_cache = KSM_KMEM_CACHE(rmap_item, 0<\/span>);<\/div>\n<\/div>\n<\/li>\n
                8. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  if<\/span> (!rmap_item_cache)<\/div>\n<\/div>\n<\/li>\n
                9. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  goto<\/span> out;<\/div>\n<\/div>\n<\/li>\n
                10. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  <\/div>\n<\/div>\n<\/li>\n
                11. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  stable_node_cache = KSM_KMEM_CACHE(stable_node, 0<\/span>);<\/div>\n<\/div>\n<\/li>\n
                12. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  if<\/span> (!stable_node_cache)<\/div>\n<\/div>\n<\/li>\n
                13. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  goto<\/span> out_free1;<\/div>\n<\/div>\n<\/li>\n
                14. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  <\/div>\n<\/div>\n<\/li>\n
                15. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  mm_slot_cache = KSM_KMEM_CACHE(mm_slot, 0<\/span>);<\/div>\n<\/div>\n<\/li>\n
                16. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  if<\/span> (!mm_slot_cache)<\/div>\n<\/div>\n<\/li>\n
                17. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  goto<\/span> out_free2;<\/div>\n<\/div>\n<\/li>\n
                18. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  <\/div>\n<\/div>\n<\/li>\n
                19. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  return<\/span> 0<\/span>;<\/div>\n<\/div>\n<\/li>\n
                20. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  <\/div>\n<\/div>\n<\/li>\n
                21. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  out_free2:<\/div>\n<\/div>\n<\/li>\n
                22. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  kmem_cache_destroy(stable_node_cache);<\/div>\n<\/div>\n<\/li>\n
                23. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  out_free1:<\/div>\n<\/div>\n<\/li>\n
                24. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  kmem_cache_destroy(rmap_item_cache);<\/div>\n<\/div>\n<\/li>\n
                25. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  out:<\/div>\n<\/div>\n<\/li>\n
                26. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  return<\/span> -ENOMEM;<\/div>\n<\/div>\n<\/li>\n
                27. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  }<\/div>\n<\/div>\n<\/li>\n
                28. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  <\/div>\n<\/div>\n<\/li>\n
                29. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  static<\/span> void<\/span> __init ksm_slab_free<\/span>(void<\/span>)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                30. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  {<\/div>\n<\/div>\n<\/li>\n
                31. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  kmem_cache_destroy(mm_slot_cache);<\/div>\n<\/div>\n<\/li>\n
                32. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  kmem_cache_destroy(stable_node_cache);<\/div>\n<\/div>\n<\/li>\n
                33. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  kmem_cache_destroy(rmap_item_cache);<\/div>\n<\/div>\n<\/li>\n
                34. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  mm_slot_cache = NULL<\/span>;<\/div>\n<\/div>\n<\/li>\n
                35. \n
                  \n
                  <\/div>\n<\/div>\n
                  \n
                  }<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                  <\/code><\/pre>\n
                  \u4e0a\u9762\u7684\u4ee3\u7801\u5f88\u7b80\u5355\uff0c\u5c31\u662f\u5efa\u7acb\u548c\u9500\u6bc1rmap_item\u3001mm_slot\u3001stable_node\u4e09\u79cd\u6570\u636e\u7c7b\u578b\u7684\u9ad8\u901f\u7f13\u5b58\u3002<\/p>\n
                  3.5 SLAB\u4e0eSLAB\u7684\u5bf9\u8c61<\/p>\n
                  \u521b\u5efa\u5b8c\u6210\u67d0\u4e00\u79cd\u6570\u636e\u7c7b\u578b\u6216\u8005\u67d0\u4e00\u79cd\u5bf9\u8c61\u7684\u9ad8\u901f\u7f13\u5b58\u4e4b\u540e\uff0c\u6211\u4eec\u53ef\u4ee5\u4ece\u8be5\u5bf9\u8c61\u7684\u9ad8\u901f\u7f13\u5b58\u4e2d\u5206\u914d\u4e0e\u91ca\u653e\u5bf9\u8c61\u3002\u5176\u4e2d\uff0ckmem_cache_alloc()\u51fd\u6570\u7528\u4e8e\u4ece\u7279\u5b9a\u7684\u7f13\u5b58\u4e2d\u83b7\u53d6\u5bf9\u8c61\uff0c\u8be5\u51fd\u6570\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
                  <\/code><\/pre>\n
                    \n
                  1. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    \/**<\/span><\/div>\n<\/div>\n<\/li>\n
                  2. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     * kmem_cache_alloc – Allocate an object<\/span><\/div>\n<\/div>\n<\/li>\n
                  3. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     * @cachep: The cache to allocate from.<\/span><\/div>\n<\/div>\n<\/li>\n
                  4. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     * @flags: See kmalloc().<\/span><\/div>\n<\/div>\n<\/li>\n
                  5. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     *<\/span><\/div>\n<\/div>\n<\/li>\n
                  6. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     * Allocate an object from this cache. The flags are only relevant<\/span><\/div>\n<\/div>\n<\/li>\n
                  7. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     * if the cache has no available objects.<\/span><\/div>\n<\/div>\n<\/li>\n
                  8. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                     *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                  9. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    void<\/span> *kmem_cache_alloc<\/span>(struct kmem_cache *cachep, gfp_t<\/span> flags)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                  10. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    {<\/div>\n<\/div>\n<\/li>\n
                  11. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    void<\/span> *ret = slab_alloc(cachep, flags, _RET_IP_);<\/div>\n<\/div>\n<\/li>\n
                  12. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    <\/div>\n<\/div>\n<\/li>\n
                  13. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    kasan_slab_alloc(cachep, ret, flags);<\/div>\n<\/div>\n<\/li>\n
                  14. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    trace_kmem_cache_alloc(_RET_IP_, ret,<\/div>\n<\/div>\n<\/li>\n
                  15. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    cachep->object_size, cachep->size, flags);<\/div>\n<\/div>\n<\/li>\n
                  16. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    return<\/span> ret;<\/div>\n<\/div>\n<\/li>\n
                  17. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    }<\/div>\n<\/div>\n<\/li>\n
                  18. \n
                    \n
                    <\/div>\n<\/div>\n
                    \n
                    EXPORT_SYMBOL(kmem_cache_alloc);<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                    <\/code><\/pre>\n
                    \u4ece\u51fd\u6570\u7684\u540d\u79f0\u3001\u53c2\u6570\u3001\u8fd4\u56de\u503c\u3001\u6ce8\u91ca\u4e2d\uff0c\u6211\u4eec\u5f88\u5bb9\u6613\u77e5\u9053kmem_cache_alloc()\u51fd\u6570\u4ece\u7ed9\u5b9a\u7684slab\u9ad8\u901f\u7f13\u5b58\u4e2d\u83b7\u53d6\u4e00\u4e2a\u6307\u5411\u7a7a\u95f2\u5bf9\u8c61\u7684\u6307\u9488\u3002\u5b9e\u9645\u4e0a\uff0c\u8fdb\u884c\u83b7\u53d6\u7a7a\u95f2\u5bf9\u8c61\u7684\u65f6\u5019\uff0c\u4f1a\u5148\u4eceper-CPU\u7f13\u5b58\u4e2d\u4e5f\u5c31\u662farray_cache\u4e2d\u67e5\u627e\u7a7a\u95f2\u5bf9\u8c61\uff0c\u5982\u679c\u6ca1\u6709\u5219\u4f1a\u4ecekmem_cache_node\u4e2d\u83b7\u53d6\u7a7a\u95f2\u5bf9\u8c61\uff0c\u5982\u679c\u4e5f\u6ca1\u6709\u5219\u9700\u8981\u5229\u7528\u4f19\u4f34\u7b97\u6cd5\u5206\u914d\u65b0\u7684\u8fde\u7eed\u9875\u6846\uff0c\u7136\u540e\u4ece\u65b0\u7684\u9875\u6846\u4e2d\u83b7\u53d6\u7a7a\u95f2\u5bf9\u8c61\u3002\u4ecekmem_cache_alloc()\u5230\u5927\u81f4\u7684\u8c03\u7528\u94fe\u5982\u4e0b\uff1a<\/p>\n
                    kmem_cache_alloc()\u2014\u2014>slab_alloc()\u2014\u2014>__do_cache_alloc()\u2014\u2014>____cache_alloc()\u2014\u2014>cpu_cache_get()\uff08\u8fd9\u91cc\u5b9e\u9645\u4e0a\u662f\u4ecearray_cache\u4e2d\u83b7\u53d6\u7a7a\u95f2\u5bf9\u8c61\uff09\u2014\u2014>cache_alloc_refill()\uff08\u8fd9\u91cc\u4f1a\u5728array_cache\u4e2d\u6ca1\u6709\u7a7a\u95f2\u5bf9\u8c61\u65f6\u6267\u884c\uff09\u2014\u2014>cpu_cache_get()\uff08\u7ecf\u8fc7cache_alloc_refill()\u7684\u6267\u884c\u57fa\u672c\u4fdd\u8bc1array_cache\u4e2d\u6709\u7a7a\u95f2\u5bf9\u8c61\uff09\u2014\u2014>\u8fd4\u56de\u53ef\u7528\u7a7a\u95f2\u5bf9\u8c61<\/p>\n
                    \u5bf9cache_alloc_refill()\u51fd\u6570\u6267\u884c\u6b65\u9aa4\u5206\u89e3\u5982\u4e0b\uff1a<\/p>\n
                    cache_alloc_refill()\u2014\u2014>\u5c1d\u8bd5\u4ece\u88ab\u4e00\u4e2aNUMA\u8282\u70b9\u6240\u6709CPU\u5171\u4eab\u7684\u7f13\u51b2\u4e2d\u83b7\u53d6\u7a7a\u95f2\u5bf9\u8c61\uff08\u6e90\u4ee3\u7801\u6ce8\u91ca\u4e2d\u5199\u9053\uff1aSee if we can refill from the shared array\uff09\uff0c\u5982\u679c\u6709\u5219\u8fd4\u56de\u53ef\u7528\u5bf9\u8c61\uff0crefill\u7ed3\u675f\u2014\u2014>\u4ecekmem_cache_node\u4e2d\u7684slab\u4e2d\u83b7\u53d6\u7a7a\u95f2\u5bf9\u8c61\uff0c\u6709\u5219\u8fd4\u56de\uff0c\u6ca1\u6709\u5c31\u6267\u884c\u4e0b\u4e00\u6b65\u2014\u2014>kmem_getpages()<\/p>\n
                    \u800ckmem_cache_free()\u51fd\u6570\u7528\u4e8e\u4ece\u7279\u5b9a\u7684\u7f13\u5b58\u4e2d\u91ca\u653e\u5bf9\u8c61\uff0c\u51fd\u6570\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
                    <\/code><\/pre>\n
                      \n
                    1. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      \/**<\/span><\/div>\n<\/div>\n<\/li>\n
                    2. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       * kmem_cache_free – Deallocate an object<\/span><\/div>\n<\/div>\n<\/li>\n
                    3. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       * @cachep: The cache the allocation was from.<\/span><\/div>\n<\/div>\n<\/li>\n
                    4. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       * @objp: The previously allocated object.<\/span><\/div>\n<\/div>\n<\/li>\n
                    5. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       *<\/span><\/div>\n<\/div>\n<\/li>\n
                    6. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       * Free an object which was previously allocated from this<\/span><\/div>\n<\/div>\n<\/li>\n
                    7. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       * cache.<\/span><\/div>\n<\/div>\n<\/li>\n
                    8. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                       *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                    9. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      void<\/span> kmem_cache_free<\/span>(struct kmem_cache *cachep, void<\/span> *objp)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                    10. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      {<\/div>\n<\/div>\n<\/li>\n
                    11. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      unsigned<\/span> long<\/span> flags;<\/div>\n<\/div>\n<\/li>\n
                    12. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      cachep = cache_from_obj(cachep, objp);<\/div>\n<\/div>\n<\/li>\n
                    13. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      if<\/span> (!cachep)<\/div>\n<\/div>\n<\/li>\n
                    14. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      return<\/span>;<\/div>\n<\/div>\n<\/li>\n
                    15. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      <\/div>\n<\/div>\n<\/li>\n
                    16. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      local_irq_save(flags);<\/div>\n<\/div>\n<\/li>\n
                    17. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      debug_check_no_locks_freed(objp, cachep->object_size);<\/div>\n<\/div>\n<\/li>\n
                    18. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      if<\/span> (!(cachep->flags & SLAB_DEBUG_OBJECTS))<\/div>\n<\/div>\n<\/li>\n
                    19. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      debug_check_no_obj_freed(objp, cachep->object_size);<\/div>\n<\/div>\n<\/li>\n
                    20. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      __cache_free(cachep, objp, _RET_IP_);<\/div>\n<\/div>\n<\/li>\n
                    21. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      local_irq_restore(flags);<\/div>\n<\/div>\n<\/li>\n
                    22. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      <\/div>\n<\/div>\n<\/li>\n
                    23. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      trace_kmem_cache_free(_RET_IP_, objp);<\/div>\n<\/div>\n<\/li>\n
                    24. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      }<\/div>\n<\/div>\n<\/li>\n
                    25. \n
                      \n
                      <\/div>\n<\/div>\n
                      \n
                      EXPORT_SYMBOL(kmem_cache_free);<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                      <\/code><\/pre>\n
                      \u91ca\u653e\u5bf9\u8c61\u4e0e\u5206\u914d\u5bf9\u8c61\u7684\u8fc7\u7a0b\u7c7b\u4f3c\uff0c\u4e0d\u518d\u8d58\u8ff0\u3002<\/p>\n
                      3.6 SLAB\u7740\u8272<\/p>\n
                      \u540c\u4e00\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\u884c\u53ef\u4ee5\u6620\u5c04RAM\u4e2d\u5f88\u591a\u4e0d\u540c\u7684\u5185\u5b58\u5757\u3002\u76f8\u540c\u5927\u5c0f\u7684\u5bf9\u8c61\u503e\u5411\u4e8e\u5b58\u653e\u5728\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\u5185\u76f8\u540c\u7684\u504f\u79fb\u91cf\u5904\u3002\u5728\u4e0d\u540c\u7684SLAB\u5185\u5177\u6709\u76f8\u540c\u504f\u79fb\u91cf\u7684\u5ea6\u4e0b\u884c\u6700\u7ec8\u5f88\u6709\u53ef\u80fd\u6620\u5c04\u5728\u540c\u4e00\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\u884c\u4e2d\u3002\u9ad8\u901f\u7f13\u5b58\u7684\u786c\u4ef6\u53ef\u80fd\u56e0\u6b64\u800c\u82b1\u8d39\u5185\u5b58\u5468\u671f\u5728\u540c\u4e00\u9ad8\u901f\u7f13\u5b58\u884c\u4e0eRAM\u5185\u5b58\u5355\u5143\u4e4b\u95f4\u6765\u6765\u5f80\u5f80\u4f20\u9001\u8fd9\u4e24\u4e2a\u5bf9\u8c61\uff0c\u800c\u5176\u4ed6\u7684\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\u884c\u5e76\u672a\u5145\u5206\u4f7f\u7528\uff08\u4ee5\u4e0a\u8bed\u53e5\u51fa\u81ea\u300a\u6df1\u5165\u7406\u89e3Linux\u5185\u6838\u300b\u7b2c\u4e09\u7248\u7b2c334\u9875\uff09\u3002SLAB\u5206\u914d\u5668\u4e3a\u4e86\u964d\u4f4e\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\u7684\u8fd9\u79cd\u884c\u4e3a\uff0c\u91c7\u7528\u4e86SLAB\u7740\u8272\uff08slab\u00a0 coloring\uff09\u7684\u7b56\u7565\u3002\u6240\u8c13\u7740\u8272\uff0c\u7b80\u5355\u6765\u8bf4\u5c31\u662f\u7ed9\u5404\u4e2aslab\u589e\u52a0\u4e0d\u540c\u7684\u504f\u79fb\u91cf\uff0c\u8bbe\u7f6e\u504f\u79fb\u91cf\u7684\u8fc7\u7a0b\u5c31\u662f\u7740\u8272\u7684\u8fc7\u7a0b\u3002\u901a\u8fc7\u7740\u8272\u5c3d\u91cf\u4f7f\u5f97\u4e0d\u540c\u7684\u5bf9\u8c61\u5bf9\u5e94\u5230\u786c\u4ef6\u4e0d\u540c\u7684\u9ad8\u901f\u7f13\u5b58\u884c\u4e0a\uff0c\u4ee5\u6700\u5927\u9650\u5ea6\u7684\u5229\u7528\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\uff0c\u63d0\u5347\u7cfb\u7edf\u6548\u7387\u3002<\/p>\n
                      3.7 \u666e\u901a\u4e0e\u4e13\u7528\u9ad8\u901f\u7f13\u5b58<\/p>\n
                      \u9ad8\u901f\u7f13\u5b58\uff08\u6307\u7684\u4e0d\u662f\u786c\u4ef6\u9ad8\u901f\u7f13\u5b58\uff09\u88ab\u5728SLAB\u4e2d\u88ab\u5206\u6210\u4e24\u79cd\u7c7b\u578b\uff1a\u666e\u901a\u548c\u4e13\u7528\u3002\u666e\u901a\u9ad8\u901f\u7f13\u5b58\u53ea\u7531SLAB\u5206\u914d\u5668\u7528\u4e8e\u81ea\u5df1\u7684\u76ee\u7684\uff0c\u800c\u4e13\u7528\u9ad8\u901f\u7f13\u5b58\u7531\u5185\u6838\u7684\u5176\u4f59\u90e8\u5206\u4f7f\u7528\u3002\u4e13\u7528\u7684\u9ad8\u901f\u7f13\u5b58\u662f\u7531kmem_cache_create()\u51fd\u6570\u521b\u5efa\u7684\uff0c\u7531kmem_cache_destroy()\u51fd\u6570\u64a4\u9500\uff0c\u7528\u4e8e\u5b58\u653e\u5bf9\u8c61\uff08\u6216\u5177\u4f53\u6570\u636e\u7c7b\u578b\uff09\uff0c\u666e\u901a\u9ad8\u901f\u7f13\u5b58\u662f\u7cfb\u7edf\u521d\u59cb\u5316\u671f\u95f4\u8c03\u7528keme_cache_init()\u5efa\u7acb\u7684\u3002\u666e\u901a\u9ad8\u901f\u7f13\u5b58\u4e2d\u5206\u914d\u548c\u91ca\u653e\u7a7a\u95f4\u4f7f\u7528kmalloc()\u548ckfree()\u51fd\u6570\u3002\u4e0b\u9762\u662fkmem_cache_init()\u51fd\u6570\u7684\u6e90\u4ee3\u7801\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
                      <\/code><\/pre>\n
                        \n
                      1. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
                      2. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * Initialisation. Called after the page allocator have been initialised and<\/span><\/div>\n<\/div>\n<\/li>\n
                      3. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * before smp_init().<\/span><\/div>\n<\/div>\n<\/li>\n
                      4. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      5. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        void<\/span> __init kmem_cache_init<\/span>(void<\/span>)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                      6. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        {<\/div>\n<\/div>\n<\/li>\n
                      7. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        int<\/span> i;<\/div>\n<\/div>\n<\/li>\n
                      8. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      9. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        BUILD_BUG_ON(sizeof<\/span>(((struct page *)NULL<\/span>)->lru) <<\/div>\n<\/div>\n<\/li>\n
                      10. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        sizeof<\/span>(struct rcu_head));<\/div>\n<\/div>\n<\/li>\n
                      11. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        kmem_cache = &kmem_cache_boot;<\/div>\n<\/div>\n<\/li>\n
                      12. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      13. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        if<\/span> (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1<\/span>)<\/div>\n<\/div>\n<\/li>\n
                      14. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        use_alien_caches = 0<\/span>;<\/div>\n<\/div>\n<\/li>\n
                      15. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      16. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        for<\/span> (i = 0<\/span>; i < NUM_INIT_LISTS; i++)<\/div>\n<\/div>\n<\/li>\n
                      17. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        kmem_cache_node_init(&init_kmem_cache_node[i]);<\/div>\n<\/div>\n<\/li>\n
                      18. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      19. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
                      20. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * Fragmentation resistance on low memory – only use bigger<\/span><\/div>\n<\/div>\n<\/li>\n
                      21. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * page orders on machines with more than 32MB of memory if<\/span><\/div>\n<\/div>\n<\/li>\n
                      22. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * not overridden on the command line.<\/span><\/div>\n<\/div>\n<\/li>\n
                      23. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      24. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        if<\/span> (!slab_max_order_set && totalram_pages > (32<\/span> << 20<\/span>) >> PAGE_SHIFT)<\/div>\n<\/div>\n<\/li>\n
                      25. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        slab_max_order = SLAB_MAX_ORDER_HI;<\/div>\n<\/div>\n<\/li>\n
                      26. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      27. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/* Bootstrap is tricky, because several objects are allocated<\/span><\/div>\n<\/div>\n<\/li>\n
                      28. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * from caches that do not exist yet:<\/span><\/div>\n<\/div>\n<\/li>\n
                      29. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * 1) initialize the kmem_cache cache: it contains the struct<\/span><\/div>\n<\/div>\n<\/li>\n
                      30. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * kmem_cache structures of all caches, except kmem_cache itself:<\/span><\/div>\n<\/div>\n<\/li>\n
                      31. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * kmem_cache is statically allocated.<\/span><\/div>\n<\/div>\n<\/li>\n
                      32. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * Initially an __init data area is used for the head array and the<\/span><\/div>\n<\/div>\n<\/li>\n
                      33. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * kmem_cache_node structures, it’s replaced with a kmalloc allocated<\/span><\/div>\n<\/div>\n<\/li>\n
                      34. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * array at the end of the bootstrap.<\/span><\/div>\n<\/div>\n<\/li>\n
                      35. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * 2) Create the first kmalloc cache.<\/span><\/div>\n<\/div>\n<\/li>\n
                      36. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * The struct kmem_cache for the new cache is allocated normally.<\/span><\/div>\n<\/div>\n<\/li>\n
                      37. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * An __init data area is used for the head array.<\/span><\/div>\n<\/div>\n<\/li>\n
                      38. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * 3) Create the remaining kmalloc caches, with minimally sized<\/span><\/div>\n<\/div>\n<\/li>\n
                      39. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * head arrays.<\/span><\/div>\n<\/div>\n<\/li>\n
                      40. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * 4) Replace the __init data head arrays for kmem_cache and the first<\/span><\/div>\n<\/div>\n<\/li>\n
                      41. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * kmalloc cache with kmalloc allocated arrays.<\/span><\/div>\n<\/div>\n<\/li>\n
                      42. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * 5) Replace the __init data for kmem_cache_node for kmem_cache and<\/span><\/div>\n<\/div>\n<\/li>\n
                      43. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * the other cache’s with kmalloc allocated memory.<\/span><\/div>\n<\/div>\n<\/li>\n
                      44. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * 6) Resize the head arrays of the kmalloc caches to their final sizes.<\/span><\/div>\n<\/div>\n<\/li>\n
                      45. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      46. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      47. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/* 1) create the kmem_cache *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      48. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      49. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
                      50. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids<\/span><\/div>\n<\/div>\n<\/li>\n
                      51. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      52. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        create_boot_cache(kmem_cache, “kmem_cache”<\/span>,<\/div>\n<\/div>\n<\/li>\n
                      53. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        offsetof(struct kmem_cache, node) +<\/div>\n<\/div>\n<\/li>\n
                      54. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        nr_node_ids * sizeof<\/span>(struct kmem_cache_node *),<\/div>\n<\/div>\n<\/li>\n
                      55. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        SLAB_HWCACHE_ALIGN);<\/div>\n<\/div>\n<\/li>\n
                      56. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        list_add(&kmem_cache->list<\/span>, &slab_caches);<\/div>\n<\/div>\n<\/li>\n
                      57. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        slab_state = PARTIAL;<\/div>\n<\/div>\n<\/li>\n
                      58. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      59. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/*<\/span><\/div>\n<\/div>\n<\/li>\n
                      60. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * Initialize the caches that provide memory for the kmem_cache_node<\/span><\/div>\n<\/div>\n<\/li>\n
                      61. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         * structures first. Without this, further allocations will bug.<\/span><\/div>\n<\/div>\n<\/li>\n
                      62. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                         *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      63. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        kmalloc_caches[INDEX_NODE] = create_kmalloc_cache(“kmalloc-node”<\/span>,<\/div>\n<\/div>\n<\/li>\n
                      64. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        kmalloc_size(INDEX_NODE), ARCH_KMALLOC_FLAGS);<\/div>\n<\/div>\n<\/li>\n
                      65. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        slab_state = PARTIAL_NODE;<\/div>\n<\/div>\n<\/li>\n
                      66. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        setup_kmalloc_cache_index_table();<\/div>\n<\/div>\n<\/li>\n
                      67. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      68. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        slab_early_init = 0<\/span>;<\/div>\n<\/div>\n<\/li>\n
                      69. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      70. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        \/* 5) Replace the bootstrap kmem_cache_node *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                      71. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        {<\/div>\n<\/div>\n<\/li>\n
                      72. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        int<\/span> nid;<\/div>\n<\/div>\n<\/li>\n
                      73. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      74. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        for_each_online_node(nid) {<\/div>\n<\/div>\n<\/li>\n
                      75. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        init_list(kmem_cache, &init_kmem_cache_node[CACHE_CACHE + nid], nid);<\/div>\n<\/div>\n<\/li>\n
                      76. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      77. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        init_list(kmalloc_caches[INDEX_NODE],<\/div>\n<\/div>\n<\/li>\n
                      78. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        &init_kmem_cache_node[SIZE_NODE + nid], nid);<\/div>\n<\/div>\n<\/li>\n
                      79. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        }<\/div>\n<\/div>\n<\/li>\n
                      80. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        }<\/div>\n<\/div>\n<\/li>\n
                      81. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        <\/div>\n<\/div>\n<\/li>\n
                      82. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        create_kmalloc_caches(ARCH_KMALLOC_FLAGS);<\/div>\n<\/div>\n<\/li>\n
                      83. \n
                        \n
                        <\/div>\n<\/div>\n
                        \n
                        }<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                        <\/code><\/pre>\n
                        \u4e0a\u9762\u7684\u4ee3\u7801\u7ed3\u5408\u4e0b\u9762\u7684\u56fe\uff0c\u83b7\u53d6\u4f1a\u66f4\u5bb9\u6613\u7406\u89e3\u4e00\u4e9b\uff1a<\/p>\n
                        \"\"<\/p>\n
                        \u5728Linux\u4e2d\u4f7f\u7528 sudo\u00a0 cat\u00a0 \/proc\/slabinfo\u5c31\u53ef\u4ee5\u5f97\u5230\u4e0a\u9762\u7684\u4fe1\u606f\uff0c\u6bcf\u4e00\u5217\u7684\u542b\u4e49\u5982\u4e0b\uff1a<\/p>\n
                        \"\"<\/p>\n
                        \u4e0b\u9762\u6211\u4eec\u91cd\u70b9\u4ecb\u7ecdkmalloc()\u51fd\u6570\uff0c\u5176\u6e90\u4ee3\u7801\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
                        <\/code><\/pre>\n
                          \n
                        1. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          \/**<\/span><\/div>\n<\/div>\n<\/li>\n
                        2. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * kmalloc – allocate memory<\/span><\/div>\n<\/div>\n<\/li>\n
                        3. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * @size: how many bytes of memory are required.<\/span><\/div>\n<\/div>\n<\/li>\n
                        4. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * @flags: the type of memory to allocate.<\/span><\/div>\n<\/div>\n<\/li>\n
                        5. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        6. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * kmalloc is the normal method of allocating memory<\/span><\/div>\n<\/div>\n<\/li>\n
                        7. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * for objects smaller than page size in the kernel.<\/span><\/div>\n<\/div>\n<\/li>\n
                        8. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        9. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * The @flags argument may be one of:<\/span><\/div>\n<\/div>\n<\/li>\n
                        10. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        11. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_USER – Allocate memory on behalf of user. May sleep.<\/span><\/div>\n<\/div>\n<\/li>\n
                        12. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        13. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_KERNEL – Allocate normal kernel ram. May sleep.<\/span><\/div>\n<\/div>\n<\/li>\n
                        14. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        15. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_ATOMIC – Allocation will not sleep. May use emergency pools.<\/span><\/div>\n<\/div>\n<\/li>\n
                        16. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * For example, use this inside interrupt handlers.<\/span><\/div>\n<\/div>\n<\/li>\n
                        17. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        18. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_HIGHUSER – Allocate pages from high memory.<\/span><\/div>\n<\/div>\n<\/li>\n
                        19. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        20. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_NOIO – Do not do any I\/O at all while trying to get memory.<\/span><\/div>\n<\/div>\n<\/li>\n
                        21. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        22. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_NOFS – Do not make any fs calls while trying to get memory.<\/span><\/div>\n<\/div>\n<\/li>\n
                        23. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        24. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_NOWAIT – Allocation will not sleep.<\/span><\/div>\n<\/div>\n<\/li>\n
                        25. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        26. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_THISNODE – Allocate node-local memory only.<\/span><\/div>\n<\/div>\n<\/li>\n
                        27. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        28. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %GFP_DMA – Allocation suitable for DMA.<\/span><\/div>\n<\/div>\n<\/li>\n
                        29. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * Should only be used for kmalloc() caches. Otherwise, use a<\/span><\/div>\n<\/div>\n<\/li>\n
                        30. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * slab created with SLAB_DMA.<\/span><\/div>\n<\/div>\n<\/li>\n
                        31. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        32. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * Also it is possible to set different flags by OR’ing<\/span><\/div>\n<\/div>\n<\/li>\n
                        33. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * in one or more of the following additional @flags:<\/span><\/div>\n<\/div>\n<\/li>\n
                        34. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        35. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_COLD – Request cache-cold pages instead of<\/span><\/div>\n<\/div>\n<\/li>\n
                        36. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * trying to return cache-warm pages.<\/span><\/div>\n<\/div>\n<\/li>\n
                        37. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        38. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_HIGH – This allocation has high priority and may use emergency pools.<\/span><\/div>\n<\/div>\n<\/li>\n
                        39. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        40. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_NOFAIL – Indicate that this allocation is in no way allowed to fail<\/span><\/div>\n<\/div>\n<\/li>\n
                        41. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * (think twice before using).<\/span><\/div>\n<\/div>\n<\/li>\n
                        42. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        43. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_NORETRY – If memory is not immediately available,<\/span><\/div>\n<\/div>\n<\/li>\n
                        44. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * then give up at once.<\/span><\/div>\n<\/div>\n<\/li>\n
                        45. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        46. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_NOWARN – If allocation fails, don’t issue any warnings.<\/span><\/div>\n<\/div>\n<\/li>\n
                        47. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        48. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * %__GFP_REPEAT – If allocation fails initially, try once more before failing.<\/span><\/div>\n<\/div>\n<\/li>\n
                        49. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *<\/span><\/div>\n<\/div>\n<\/li>\n
                        50. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * There are other flags available as well, but these are not intended<\/span><\/div>\n<\/div>\n<\/li>\n
                        51. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * for general use, and so are not documented here. For a full list of<\/span><\/div>\n<\/div>\n<\/li>\n
                        52. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           * potential flags, always refer to linux\/gfp.h.<\/span><\/div>\n<\/div>\n<\/li>\n
                        53. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                           *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                        54. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          static<\/span> __always_inline void<\/span> *kmalloc<\/span>(size_t<\/span> size, gfp_t<\/span> flags)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                        55. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          {<\/div>\n<\/div>\n<\/li>\n
                        56. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          if<\/span> (__builtin_constant_p(size)) {<\/div>\n<\/div>\n<\/li>\n
                        57. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          if<\/span> (size > KMALLOC_MAX_CACHE_SIZE)<\/div>\n<\/div>\n<\/li>\n
                        58. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          return<\/span> kmalloc_large(size, flags);<\/div>\n<\/div>\n<\/li>\n
                        59. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          #ifndef<\/span> CONFIG_SLOB<\/span><\/div>\n<\/div>\n<\/li>\n
                        60. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          if<\/span> (!(flags & GFP_DMA)) {<\/div>\n<\/div>\n<\/li>\n
                        61. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          int<\/span> index = kmalloc_index(size);<\/div>\n<\/div>\n<\/li>\n
                        62. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          <\/div>\n<\/div>\n<\/li>\n
                        63. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          if<\/span> (!index)<\/div>\n<\/div>\n<\/li>\n
                        64. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          return<\/span> ZERO_SIZE_PTR;<\/div>\n<\/div>\n<\/li>\n
                        65. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          <\/div>\n<\/div>\n<\/li>\n
                        66. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          return<\/span> kmem_cache_alloc_trace(kmalloc_caches[index],<\/div>\n<\/div>\n<\/li>\n
                        67. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          flags, size);<\/div>\n<\/div>\n<\/li>\n
                        68. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          }<\/div>\n<\/div>\n<\/li>\n
                        69. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          #endif<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                        70. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          }<\/div>\n<\/div>\n<\/li>\n
                        71. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          return<\/span> __kmalloc(size, flags);<\/div>\n<\/div>\n<\/li>\n
                        72. \n
                          \n
                          <\/div>\n<\/div>\n
                          \n
                          }<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                          <\/code><\/pre>\n
                          \u51fd\u6570\u53c2\u6570\u4e2d\u7684size\u8868\u793a\u8bf7\u6c42\u5206\u914d\u7684\u5b57\u8282\u6570\uff0c\u9700\u8981\u6ce8\u610f\u7684\u662fkmalloc()\u51fd\u6570\u5206\u914d\u7684\u662f\u8fde\u7eed\u7684\u7269\u7406\u5185\u5b58\u3002<\/p>\n
                          \u4e0ekmalloc()\u51fd\u6570\u76f8\u5bf9\u7684\u662fkfree()\u51fd\u6570\uff0c\u5176\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
                          <\/code><\/pre>\n
                            \n
                          1. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            \/**<\/span><\/div>\n<\/div>\n<\/li>\n
                          2. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             * kfree – free previously allocated memory<\/span><\/div>\n<\/div>\n<\/li>\n
                          3. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             * @objp: pointer returned by kmalloc.<\/span><\/div>\n<\/div>\n<\/li>\n
                          4. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             *<\/span><\/div>\n<\/div>\n<\/li>\n
                          5. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             * If @objp is NULL, no operation is performed.<\/span><\/div>\n<\/div>\n<\/li>\n
                          6. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             *<\/span><\/div>\n<\/div>\n<\/li>\n
                          7. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             * Don’t free memory not originally allocated by kmalloc()<\/span><\/div>\n<\/div>\n<\/li>\n
                          8. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             * or you will run into trouble.<\/span><\/div>\n<\/div>\n<\/li>\n
                          9. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                             *\/<\/span><\/div>\n<\/div>\n<\/li>\n
                          10. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            void<\/span> kfree<\/span>(const<\/span> void<\/span> *objp)<\/span><\/span><\/div>\n<\/div>\n<\/li>\n
                          11. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            {<\/div>\n<\/div>\n<\/li>\n
                          12. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            struct<\/span> kmem_cache<\/span> *c<\/span>;<\/span><\/div>\n<\/div>\n<\/li>\n
                          13. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            unsigned<\/span> long<\/span> flags;<\/div>\n<\/div>\n<\/li>\n
                          14. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            <\/div>\n<\/div>\n<\/li>\n
                          15. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            trace_kfree(_RET_IP_, objp);<\/div>\n<\/div>\n<\/li>\n
                          16. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            <\/div>\n<\/div>\n<\/li>\n
                          17. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            if<\/span> (unlikely(ZERO_OR_NULL_PTR(objp)))<\/div>\n<\/div>\n<\/li>\n
                          18. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            return<\/span>;<\/div>\n<\/div>\n<\/li>\n
                          19. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            local_irq_save(flags);<\/div>\n<\/div>\n<\/li>\n
                          20. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            kfree_debugcheck(objp);<\/div>\n<\/div>\n<\/li>\n
                          21. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            c = virt_to_cache(objp);<\/div>\n<\/div>\n<\/li>\n
                          22. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            debug_check_no_locks_freed(objp, c->object_size);<\/div>\n<\/div>\n<\/li>\n
                          23. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            <\/div>\n<\/div>\n<\/li>\n
                          24. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            debug_check_no_obj_freed(objp, c->object_size);<\/div>\n<\/div>\n<\/li>\n
                          25. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            __cache_free(c, (void<\/span> *)objp, _RET_IP_);<\/div>\n<\/div>\n<\/li>\n
                          26. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            local_irq_restore(flags);<\/div>\n<\/div>\n<\/li>\n
                          27. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            }<\/div>\n<\/div>\n<\/li>\n
                          28. \n
                            \n
                            <\/div>\n<\/div>\n
                            \n
                            EXPORT_SYMBOL(kfree);<\/div>\n<\/div>\n<\/li>\n<\/ol>\n
                            <\/code><\/pre>\n
                            kfree()\u51fd\u6570\u7528\u4e8e\u91ca\u653e\u7531kmalloc()\u51fd\u6570\u5206\u914d\u7684\u8fde\u7eed\u5185\u5b58\u7a7a\u95f4\u3002kmalloc()\u5206\u914d\u7684\u662f\u5185\u6838\u5185\u5b58\uff0c\u4f46\u662f\u5176\u5206\u914d\u7684\u5927\u5c0f\u662f\u6709\u9650\u5236\u7684\u3002<\/p>\n
                            3.8 SLAB\u5206\u914d\u5668\u4f53\u73b0\u7684\u6539\u8fdb\u601d\u60f3\uff1a<\/p>\n
                            \uff081\uff09SLAB\u5206\u914d\u5668\u628a\u5185\u5b58\u533a\u770b\u6210\u5bf9\u8c61<\/p>\n
                            \uff082\uff09SLAB\u5206\u914d\u5668\u5427\u5bf9\u8c61\u5206\u7ec4\u653e\u8fdb\u9ad8\u901f\u7f13\u5b58<\/p>\n
                            \uff083\uff09\u6bcf\u4e2aSLAB\u90fd\u662f\u540c\u79cd\u7c7b\u578b\u7684\u5185\u5b58\u5bf9\u8c61<\/p>\n
                             <\/p>\n
                            \u5982\u4e0a\u6587\u5185\u5bb9\u6709\u4e0d\u5f53\u4e4b\u5904\uff0c\u8bf7\u6279\u8bc4\u6307\u9488\uff0c\u8c22\u8c22\uff01<\/p>\n
                             <\/p>\n<\/div>\n<\/div>\n<\/article>\n","protected":false},"excerpt":{"rendered":"
                            \u539f\u6587\u5730\u5740 \u5206\u7c7b\u4e13\u680f\uff1a\u00a0Linux\u5185\u5b58\u7ba1\u7406<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[119],"class_list":["post-4509","post","type-post","status-publish","format-standard","hentry","tag-03-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4509","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=4509"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4509\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=4509"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=4509"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=4509"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
            \u521b\u5efa\u65b0\u7684slab\u7f13\u5b58\u9700\u8981\u8c03\u7528\u51fd\u6570kmem_cache_create()\u3002\u8be5\u51fd\u6570\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n
            \u5176\u4e2d\uff0c\u53c2\u6570cachep\u6307\u5411\u9700\u8981\u989d\u5916\u9875\u6846\u7684\u9ad8\u901f\u7f13\u5b58\u7684\u9ad8\u901f\u7f13\u5b58\u63cf\u8ff0\u7b26\uff08\u8bf7\u6c42\u9875\u6846\u7684\u4e2a\u6570\u5b58\u653e\u5728cache->gfporder\u5b57\u6bb5\u4e2d\u7684order\u51b3\u5b9a\uff09\uff0cflags\u8bf4\u660e\u5982\u4f55\u8bf7\u6c42\u9875\u6846\uff0cnodeid\u6307\u660e\u4ece\u54ea\u4e2aNUMA\u8282\u70b9\u7684\u5185\u5b58\u4e2d\u8bf7\u6c42\u9875\u6846\u3002\u4e0ekmem_getpages()\u51fd\u6570\u76f8\u5bf9\u7684\u662fkmem_freepages()\uff0ckmem_freepages()\u51fd\u6570\u53ef\u4ee5\u91ca\u653e\u5206\u914d\u7ed9slab\u7684\u9875\u6846\u3002kmem_freepages()\u51fd\u6570\u5b9a\u4e49\u5982\u4e0b\uff1a\u6e90\u4ee3\u7801\u7f51\u5740<\/a><\/p>\n