korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-23 20:24:12 +08:00
Code Issues Packages Projects Releases Wiki Activity

workqueue: add find_worker_executing_work() and track current_cwq

Browse Source 
Now that all the workers are tracked by gcwq, we can find which worker
is executing a work from gcwq.  Implement find_worker_executing_work()
and make worker track its current_cwq so that we can find things the
other way around.  This will be used to implement non-reentrant wqs.

Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Tejun Heo 2010-06-29 10:07:13 +02:00
parent 502ca9d819
commit 8cca0eea39
1 changed files with 56 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
kernel/workqueue.c
View File

@ -82,6 +82,7 @@ struct worker {
};
struct work_struct *current_work; /* L: work being processed */
struct cpu_workqueue_struct *current_cwq; /* L: current_work's cwq */
struct list_head scheduled; /* L: scheduled works */
struct task_struct *task; /* I: worker task */
struct global_cwq *gcwq; /* I: the associated gcwq */
@ -372,6 +373,59 @@ static struct hlist_head *busy_worker_head(struct global_cwq *gcwq,
return &gcwq->busy_hash[v];
}
/**
* __find_worker_executing_work - find worker which is executing a work
* @gcwq: gcwq of interest
* @bwh: hash head as returned by busy_worker_head()
* @work: work to find worker for
*
* Find a worker which is executing @work on @gcwq. @bwh should be
* the hash head obtained by calling busy_worker_head() with the same
* work.
*
* CONTEXT:
* spin_lock_irq(gcwq->lock).
*
* RETURNS:
* Pointer to worker which is executing @work if found, NULL
* otherwise.
*/
static struct worker *__find_worker_executing_work(struct global_cwq *gcwq,
struct hlist_head *bwh,
struct work_struct *work)
{
struct worker *worker;
struct hlist_node *tmp;
hlist_for_each_entry(worker, tmp, bwh, hentry)
if (worker->current_work == work)
return worker;
return NULL;
}
/**
* find_worker_executing_work - find worker which is executing a work
* @gcwq: gcwq of interest
* @work: work to find worker for
*
* Find a worker which is executing @work on @gcwq. This function is
* identical to __find_worker_executing_work() except that this
* function calculates @bwh itself.
*
* CONTEXT:
* spin_lock_irq(gcwq->lock).
*
* RETURNS:
* Pointer to worker which is executing @work if found, NULL
* otherwise.
*/
static struct worker *find_worker_executing_work(struct global_cwq *gcwq,
struct work_struct *work)
{
return __find_worker_executing_work(gcwq, busy_worker_head(gcwq, work),
work);
}
/**
* insert_work - insert a work into cwq
* @cwq: cwq @work belongs to
@ -914,6 +968,7 @@ static void process_one_work(struct worker *worker, struct work_struct *work)
debug_work_deactivate(work);
hlist_add_head(&worker->hentry, bwh);
worker->current_work = work;
worker->current_cwq = cwq;
work_color = get_work_color(work);
list_del_init(&work->entry);
@ -942,6 +997,7 @@ static void process_one_work(struct worker *worker, struct work_struct *work)
/* we're done with it, release */
hlist_del_init(&worker->hentry);
worker->current_work = NULL;
worker->current_cwq = NULL;
cwq_dec_nr_in_flight(cwq, work_color);
}