{"id":1547,"date":"2010-10-04T13:16:53","date_gmt":"2010-10-04T05:16:53","guid":{"rendered":"http:\/\/edsionte.com\/techblog\/?p=1547"},"modified":"2010-10-06T19:37:35","modified_gmt":"2010-10-06T11:37:35","slug":"tasklet%e6%9c%ba%e5%88%b6","status":"publish","type":"post","link":"http:\/\/edsionte.com\/techblog\/archives\/1547","title":{"rendered":"\u4e2d\u65ad\u4e0b\u534a\u90e8-tasklet"},"content":{"rendered":"

\u672c\u6587\u5305\u542b\u90a3\u4e9b\u5185\u5bb9\uff1f
\ntasklet\u673a\u5236\u6982\u8ff0\uff1btasklet\u673a\u5236\u7684\u4f7f\u7528\u65b9\u6cd5\uff1b\u4e00\u4e2a\u9610\u8ff0tasklet\u673a\u5236\u8c03\u7528\u5173\u7cfb\u7684\u4e3e\u4f8b\u3002
\n\u672c\u6587\u9002\u5408\u90a3\u4e9b\u4eba\u9605\u8bfb\uff1f
\n\u60f3\u4e86\u89e3linuxer\uff1b\u5b66\u4e60\u9a71\u52a8\u5f00\u53d1\u7684beginner\uff1b\u5b66\u4e60\u5185\u6838\u6a21\u5757\u7f16\u7a0bbeginner\uff1b\u5176\u4ed6super linux NBer\uff1b
\n\u53c2\u8003\u4e66\u7c4d\uff1a
\n<\/em><\/strong>Linux\u5185\u6838\u8bbe\u8ba1\u4e0e\u5b9e\u73b0<\/em><\/strong><\/a>
\n<\/em><\/strong>Linux\u64cd\u4f5c\u7cfb\u7edf\u539f\u7406\u4e0e\u5e94\u7528<\/em><\/strong><\/a>
\n
\n<\/strong>
\n<\/p>\n

tasklet\u7684\u5b9e\u73b0<\/h4>\n

<\/strong>
\ntasklet\uff08\u5c0f\u4efb\u52a1\uff09\u673a\u5236\u662f\u4e2d\u65ad\u5904\u7406\u4e0b\u534a\u90e8\u5206\u6700\u5e38\u7528\u7684\u4e00\u79cd\u65b9\u6cd5\uff0c\u5176\u4f7f\u7528\u4e5f\u662f\u975e\u5e38\u7b80\u5355\u7684\u3002\u6b63\u5982\u5728\u524d\u6587\u4e2d\u4f60\u6240\u77e5\u9053\u7684\u90a3\u6837\uff0c\u4e00\u4e2a\u4f7f\u7528tasklet\u7684\u4e2d\u65ad\u7a0b\u5e8f\u9996\u5148\u4f1a\u901a\u8fc7\u6267\u884c\u4e2d\u65ad\u5904\u7406\u7a0b\u5e8f\u6765\u5feb\u901f\u5b8c\u6210\u4e0a\u534a\u90e8\u5206\u7684\u5de5\u4f5c\uff0c\u63a5\u7740\u901a\u8fc7\u8c03\u7528tasklet\u4f7f\u5f97\u4e0b\u534a\u90e8\u5206\u7684\u5de5\u4f5c\u5f97\u4ee5\u5b8c\u6210\u3002\u53ef\u4ee5\u770b\u5230\uff0c\u4e0b\u534a\u90e8\u5206\u88ab\u4e0a\u534a\u90e8\u5206\u6240\u8c03\u7528\uff0c\u81f3\u4e8e\u4e0b\u534a\u90e8\u5206\u4f55\u65f6\u6267\u884c\u5219\u5c5e\u4e8e\u5185\u6838\u7684\u5de5\u4f5c\u3002\u5bf9\u5e94\u5230\u6211\u4eec\u6b64\u523b\u6240\u8bf4\u7684tasklet\u5c31\u662f\uff0c\u5728\u4e2d\u65ad\u5904\u7406\u7a0b\u5e8f\u4e2d\uff0c\u9664\u4e86\u5b8c\u6210\u5bf9\u4e2d\u65ad\u7684\u54cd\u5e94\u7b49\u5de5\u4f5c\uff0c\u8fd8\u8981\u8c03\u7528tasklet\uff0c\u5982\u4e0b\u56fe\u793a\u3002<\/p>\n

\"\"<\/a> tasklet\u7531tasklet_struct\u7ed3\u6784\u4f53\u6765\u8868\u793a\uff0c\u6bcf\u4e00\u4e2a\u8fd9\u6837\u7684\u7ed3\u6784\u4f53\u5c31\u8868\u793a\u4e00\u4e2atasklet\u3002\u5728<linux\/interrupt.h>\u4e2d\u53ef\u4ee5\u770b\u5230\u5982\u4e0b\u7684\u5b9a\u4e49\uff1a<\/p>\n

tasklet_struct\r\n{\r\n\tstruct tasklet_struct *next;\r\n\tunsigned long state;\r\n\tatomic_t count;\r\n\tvoid (*func)(unsigned long);\r\n\tunsigned long data;\r\n};<\/pre>\n
\u5728\u8fd9\u4e2a\u7ed3\u6784\u4f53\u4e2d\uff0c\u7b2c\u4e00\u4e2a\u6210\u5458\u4ee3\u8868\u94fe\u8868\u4e2d\u7684\u4e0b\u4e00\u4e2atasklet\u3002\u7b2c\u4e8c\u4e2a\u53d8\u91cf\u4ee3\u8868\u6b64\u523btasklet\u7684\u72b6\u6001\uff0c\u4e00\u822c\u4e3aTASKLET_STATE_SCHED,\u8868\u793a\u6b64tasklet\u5df2\u88ab\u8c03\u5ea6\u4e14\u6b63\u51c6\u5907\u8fd0\u884c\uff1b\u6b64\u53d8\u91cf\u8fd8\u53ef\u53d6TASKLET_STATE_RUN\uff0c\u8868\u793a\u6b63\u5728\u8fd0\u884c\uff0c\u4f46\u53ea\u7528\u5728\u591a\u5904\u7406\u5668\u7684\u60c5\u51b5\u4e0b\u3002count\u6210\u5458\u662f\u4e00\u4e2a\u5f15\u7528\u8ba1\u6570\u5668\uff0c\u53ea\u6709\u5f53\u5176\u503c\u4e3a0\u65f6\u5019\uff0ctasklet\u624d\u4f1a\u88ab\u6fc0\u6d3b\uff1b\u5426\u5219\u88ab\u7981\u6b62\uff0c\u4e0d\u80fd\u88ab\u6267\u884c\u3002\u800c\u63a5\u4e0b\u6765\u7684func\u53d8\u91cf\u5f88\u660e\u663e\u662f\u4e00\u4e2a\u51fd\u6570\u6307\u9488\uff0c\u5b83\u6307\u5411tasklet\u5904\u7406\u51fd\u6570\uff0c\u8fd9\u4e2a\u5904\u7406\u51fd\u6570\u7684\u552f\u4e00\u53c2\u6570\u4e3adata\u3002
\n
\n<\/strong>
\n<\/p>\n
\u4f7f\u7528tasklet<\/h4>\n
<\/strong>
\n\u5728\u4f7f\u7528tasklet\u524d\uff0c\u5fc5\u987b\u9996\u5148\u521b\u5efa\u4e00\u4e2atasklet_struct\u7c7b\u578b\u7684\u53d8\u91cf\u3002\u901a\u5e38\u6709\u4e24\u79cd\u65b9\u6cd5\uff1a\u9759\u6001\u521b\u5efa\u548c\u52a8\u6001\u521b\u5efa\u3002\u8fd9\u6837\u5b98\u65b9\u7684\u8bf4\u6cd5\u4ecd\u7136\u4f7f\u6211\u4eec\u4e0d\u80fd\u7406\u89e3\u8fd9\u4e24\u79cd\u521b\u5efa\u5230\u5e95\u662f\u600e\u4e48\u4e00\u56de\u4e8b\u3002\u4e0d\u591f\u900f\u8fc7\u6e90\u7801\u6765\u5206\u6790\u5012\u662f\u53ef\u4ee5\u641e\u660e\u767d\u3002<\/p>\n
\u5728<linux\/interrupt.h>\u4e2d\u7684\u4e24\u4e2a\u5b8f\uff1a<\/p>\n
 464#define DECLARE_TASKLET(name, func, data) \\\r\n 465struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }\r\n 466\r\n 467#define DECLARE_TASKLET_DISABLED(name, func, data) \\\r\n 468struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }<\/pre>\n
\u5c31\u662f\u6211\u4eec\u8fdb\u884c\u9759\u6001\u521b\u5efatasklet\u7684\u4e24\u79cd\u65b9\u6cd5\u3002\u901a\u8fc7\u7b2c\u4e00\u4e2a\u5b8f\u521b\u5efa\u7684tasklet\u5904\u4e8e\u6fc0\u6d3b\u72b6\u6001\uff0c\u518d\u901a\u8fc7\u8c03\u5ea6\u51fd\u6570\u88ab\u6302\u8d77\u5c3d\u800c\u88ab\u5185\u6838\u6267\u884c\uff1b\u800c\u901a\u8fc7\u7b2c\u4e8c\u4e2a\u5b8f\u521b\u5efa\u7684tasklet\u5904\u4e8e\u7981\u6b62\u72b6\u6001\u3002\u4ece\u4e24\u4e2a\u5b8f\u7684\u5b9a\u4e49\u53ef\u4ee5\u770b\u5230\uff0c\u6240\u8c13\u7684\u9759\u6001\u521b\u5efa\u5c31\u662f\u76f4\u63a5\u5b9a\u4e49\u4e2a\u4e00\u4e2a\u540d\u4e3aname\u7684tasklet_struct\u7c7b\u578b\u7684\u53d8\u91cf\uff0c\u5e76\u5c06\u5b8f\u4e2d\u5404\u4e2a\u53c2\u6570\u76f8\u5e94\u7684\u8d4b\u503c\u7ed9\u8fd9\u4e2aname\u53d8\u91cf\u7684\u5404\u4e2a\u6210\u5458\u3002\u6ce8\u610f\uff0c\u4e24\u4e2a\u5b8f\u5728\u529f\u80fd\u4e0a\u5dee\u5f02\u5c31\u5728\u4e8e\u5bf9name\u53d8\u91cfcount\u6210\u5458\u7684\u8d4b\u503c\u4e0a\uff0c\u5177\u4f53\u539f\u56e0\u5728\u7b2c\u4e00\u90e8\u5206\u5df2\u7ecf\u8bf4\u660e\u3002\u4e5f\u8bb8\u4f60\u5bf9ATOMIC_INIT\u8fd9\u6837\u7684\u521d\u59cb\u5316\u65b9\u5f0f\u611f\u5230\u7591\u60d1\uff0c\u90a3\u4e48\u770b\u5b8c\u5b9a\u4e49\u540e\uff0c\u4f60\u5c31\u4f1a\u4e00\u76ee\u4e86\u7136\uff1a<\/p>\n
 \/\/\u5728arch\/x86\/include\/asm\/atomic.h\u4e2d\r\n 15#define ATOMIC_INIT(i)  { (i) }\r\n \/\/\u5728linux\/types.h\u4e2d\r\n 190typedef struct {\r\n 191        int counter;\r\n 192} atomic_t;<\/pre>\n
\u4e0e\u9759\u6001\u521b\u5efa\u76f8\u5bf9\u7684\u662f\u52a8\u6001\u521b\u5efa\uff0c\u901a\u8fc7\u7ed9tasklet_init\u51fd\u6570\u4f20\u9012\u4e00\u4e2a\u4e8b\u5148\u5b9a\u4e49\u7684\u6307\u9488\uff0c\u6765\u52a8\u6001\u521b\u5efa\u4e00\u4e2atasklet\u3002\u8fd9\u4e2a\u51fd\u6570\u6e90\u7801\u5982\u4e0b\u3002<\/p>\n
 470void tasklet_init(struct tasklet_struct *t,\r\n 471                  void (*func)(unsigned long), unsigned long data)\r\n 472{\r\n 473        t->next = NULL;\r\n 474        t->state = 0;\r\n 475        atomic_set(&t->count, 0);\r\n 476        t->func = func;\r\n 477        t->data = data;\r\n 478}<\/pre>\n
\u76f8\u4fe1\u4f60\u5728\u9605\u8bfb\u4e0a\u9762\u7684\u4ee3\u7801\u662f\u57fa\u672c\u4e0a\u6ca1\u6709\u4ec0\u4e48\u96be\u4ee5\u7406\u89e3\u7684\u5730\u65b9\uff0c\u4e0d\u8fc7\u8fd9\u91cc\u8fd8\u662f\u8981\u7279\u522b\u8bf4\u660e\u4e00\u4e0batomic_set\u51fd\u6570\uff1a<\/p>\n
  \/\/\u5728arch\/x86\/include\/asm\/atomic.h\u4e2d\r\n  35static inline void atomic_set(atomic_t *v, int i)\r\n  36{\r\n  37        v->counter = i;\r\n  38}<\/pre>\n
\u9996\u5148tasklet_init\u5f53\u4e2d\uff0c\u5c06&t->count\u4f20\u9012\u7ed9\u4e86\u6b64\u51fd\u6570\u3002\u4e5f\u5c31\u662f\u8bf4\u5c06atomic_t\u7c7b\u578b\u7684\u6210\u5458count\u7684\u5730\u5740\u4f20\u9012\u7ed9\u4e86atomic_set\u51fd\u6570\u3002\u800c\u6211\u4eec\u5728\u6b64\u51fd\u6570\u4e2d\u5374\u8981\u4e3acount\u53d8\u91cf\u4e2d\u7684\u6210\u5458counter\u8d4b\u503c\u3002\u5982\u679c\u8bf4\u6211\u4eec\u5f53\u524d\u8981\u4f7f\u7528i\uff0c\u90a3\u4e48\u5e94\u8be5\u662f\u5982\u4e0b\u7684\u5f15\u7528\u65b9\u6cd5\uff1at-\u300bcount.i\u3002\u660e\u767d\u4e86\u5417\uff1f<\/p>\n
ok\uff0c\u901a\u8fc7\u4e0a\u8ff0\u4e24\u79cd\u65b9\u6cd5\u5c31\u53ef\u4ee5\u521b\u5efa\u4e00\u4e2atasklet\u4e86\u3002\u540c\u65f6\uff0c\u4f60\u5e94\u8be5\u6ce8\u610f\u5230\u4e0d\u7ba1\u662f\u4e0a\u8ff0\u90a3\u79cd\u521b\u5efa\u65b9\u5f0f\u90fd\u6709func\u53c2\u6570\u3002\u900f\u8fc7\u4e0a\u8ff0\u5206\u6790\u7684\u6e90\u7801\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230func\u53c2\u6570\u662f\u4e00\u4e2a\u51fd\u6570\u6307\u9488\uff0c\u5b83\u6307\u5411\u7684\u662f\u8fd9\u6837\u7684\u4e00\u4e2a\u51fd\u6570\uff1a<\/p>\n
void tasklet_handler(unsigned long data);<\/pre>\n
\u5982\u540c\u4e0a\u534a\u90e8\u5206\u7684\u4e2d\u65ad\u5904\u7406\u7a0b\u5e8f\u4e00\u6837\uff0c\u8fd9\u4e2a\u51fd\u6570\u9700\u8981\u6211\u4eec\u81ea\u5df1\u6765\u5b9e\u73b0\u3002<\/p>\n
\u521b\u5efa\u597d\u4e4b\u540e\uff0c\u6211\u4eec\u8fd8\u8981\u901a\u8fc7\u5982\u4e0b\u7684\u65b9\u6cd5\u5bf9tasklet\u8fdb\u884c\u8c03\u5ea6\uff1a<\/p>\n
tasklet_schedule(&my_tasklet)<\/pre>\n
\u901a\u8fc7\u6b64\u51fd\u6570\u7684\u8c03\u7528\uff0c\u6211\u4eec\u7684tasklet\u5c31\u4f1a\u88ab\u6302\u8d77\uff0c\u7b49\u5f85\u673a\u4f1a\u88ab\u6267\u884c
\n
\n<\/strong>
\n<\/p>\n
\u4e00\u4e2a\u4e3e\u4f8b<\/h4>\n
<\/strong>
\n\u5728\u6b64\u53ea\u5206\u6790\u4e0a\u4e0b\u4e24\u90e8\u5206\u7684\u8c03\u7528\u5173\u7cfb\uff0c\u5b8c\u6574\u4ee3\u7801\u5728\u8fd9\u91cc<\/a>\u67e5\u770b\u3002<\/p>\n
\/\/define a argument of tasklet struct\r\nstatic struct tasklet_struct mytasklet;\r\n\r\nstatic void mytasklet_handler(unsigned long data)\r\n{\r\n\tprintk(\"This is tasklet handler..\\n\");\r\n}\r\n\r\nstatic irqreturn_t myirq_handler(int irq,void* dev)\r\n{\r\n\tstatic int count=0;\r\n\tif(count<10)\r\n\t{\r\n\t\tprintk(\"-----------%d start--------------------------\\n\",count+1);\r\n            \tprintk(\"The interrupt handeler is working..\\n\");\r\n             \tprintk(\"The most of interrupt work will be done by following tasklet..\\n\");\r\n            \ttasklet_init(&mytasklet,mytasklet_handler,0);\r\n          \ttasklet_schedule(&mytasklet);\r\n             \tprintk(\"The top half has been done and bottom half will be processed..\\n\");\r\n\t}\r\n\tcount++;\r\n      \treturn IRQ_HANDLED;\r\n}<\/pre>\n
\u4ece\u4ee3\u7801\u4e2d\u53ef\u4ee5\u770b\u5230\uff0c\u5728\u4e0a\u534a\u90e8\u4e2d\u901a\u8fc7\u8c03\u7528tasklet\uff0c\u4f7f\u5f97\u5bf9\u65f6\u95f4\u8981\u6c42\u5bbd\u677e\u7684\u90a3\u90e8\u5206\u4e2d\u65ad\u7a0b\u5e8f\u63a8\u540e\u6267\u884c\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u672c\u6587\u5305\u542b\u90a3\u4e9b\u5185\u5bb9\uff1f tasklet\u673a\u5236\u6982\u8ff0\uff1btasklet\u673a\u5236\u7684\u4f7f\u7528\u65b9\u6cd5\uff1b\u4e00\u4e2a\u9610\u8ff0tasklet\u673a\u5236\u8c03\u7528\u5173\u7cfb\u7684 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[110],"tags":[108,157,147],"class_list":["post-1547","post","type-post","status-publish","format-standard","hentry","category-linux","tag-linux","tag-157","tag-147"],"views":27639,"_links":{"self":[{"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/posts\/1547","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/comments?post=1547"}],"version-history":[{"count":0,"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/posts\/1547\/revisions"}],"wp:attachment":[{"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/media?parent=1547"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/categories?post=1547"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/edsionte.com\/techblog\/wp-json\/wp\/v2\/tags?post=1547"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}