Commit 8bf89593 authored by Tejun Heo's avatar Tejun Heo
Browse files

workqueue: Set worker->desc to workqueue name by default 



Work functions can use set_worker_desc() to improve the visibility of
what the worker task is doing.  Currently, the desc field is unset at
the beginning of each execution and there is a separate field to track
the field is set during the current execution.

Instead of leaving empty till desc is set, worker->desc can be used to
remember the last workqueue the worker worked on by default and users
that use set_worker_desc() can override it to something more
informative as necessary.

This simplifies desc handling and helps tracking the last workqueue
that the worker exected on to improve visibility.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent a2d812a2

kernel/workqueue.c

+10 −11
Original line number Diff line number Diff line
@@ -2088,6 +2088,12 @@ __acquires(&pool->lock) 
	worker->current_pwq = pwq;

	work_color = get_work_color(work);



	/*

	 * Record wq name for cmdline and debug reporting, may get

	 * overridden through set_worker_desc().

	 */

	strscpy(worker->desc, pwq->wq->name, WORKER_DESC_LEN);



	list_del_init(&work->entry);



	/*
@@ -2183,7 +2189,6 @@ __acquires(&pool->lock) 
	worker->current_work = NULL;

	worker->current_func = NULL;

	worker->current_pwq = NULL;

	worker->desc_valid = false;

	pwq_dec_nr_in_flight(pwq, work_color);

}
@@ -4346,7 +4351,6 @@ void set_worker_desc(const char *fmt, ...) 
		va_start(args, fmt);

		vsnprintf(worker->desc, sizeof(worker->desc), fmt, args);

		va_end(args);

		worker->desc_valid = true;

	}

}
@@ -4370,7 +4374,6 @@ void print_worker_info(const char *log_lvl, struct task_struct *task) 
	char desc[WORKER_DESC_LEN] = { };

	struct pool_workqueue *pwq = NULL;

	struct workqueue_struct *wq = NULL;

	bool desc_valid = false;

	struct worker *worker;



	if (!(task->flags & PF_WQ_WORKER))
@@ -4383,22 +4386,18 @@ void print_worker_info(const char *log_lvl, struct task_struct *task) 
	worker = kthread_probe_data(task);



	/*

	 * Carefully copy the associated workqueue's workfn and name.  Keep

	 * the original last '\0' in case the original contains garbage.

	 * Carefully copy the associated workqueue's workfn, name and desc.

	 * Keep the original last '\0' in case the original is garbage.

	 */

	probe_kernel_read(&fn, &worker->current_func, sizeof(fn));

	probe_kernel_read(&pwq, &worker->current_pwq, sizeof(pwq));

	probe_kernel_read(&wq, &pwq->wq, sizeof(wq));

	probe_kernel_read(name, wq->name, sizeof(name) - 1);



	/* copy worker description */

	probe_kernel_read(&desc_valid, &worker->desc_valid, sizeof(desc_valid));

	if (desc_valid)

	probe_kernel_read(desc, worker->desc, sizeof(desc) - 1);



	if (fn || name[0] || desc[0]) {

		printk("%sWorkqueue: %s %pf", log_lvl, name, fn);

		if (desc[0])

		if (strcmp(name, desc))

			pr_cont(" (%s)", desc);

		pr_cont("\n");

	}

kernel/workqueue_internal.h

+0 −1
Original line number Diff line number Diff line
@@ -31,7 +31,6 @@ struct worker { 
	struct work_struct	*current_work;	/* L: work being processed */

	work_func_t		current_func;	/* L: current_work's fn */

	struct pool_workqueue	*current_pwq; /* L: current_work's pwq */

	bool			desc_valid;	/* ->desc is valid */

	struct list_head	scheduled;	/* L: scheduled works */



	/* 64 bytes boundary on 64bit, 32 on 32bit */

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