Commit 7245d24f authored by Tejun Heo's avatar Tejun Heo
Browse files

backtracetest: Convert from tasklet to BH workqueue 



The only generic interface to execute asynchronously in the BH context is
tasklet; however, it's marked deprecated and has some design flaws. To
replace tasklets, BH workqueue support was recently added. A BH workqueue
behaves similarly to regular workqueues except that the queued work items
are executed in the BH context.

This patch converts backtracetest from tasklet to BH workqueue.

- Replace "irq" with "bh" in names and message to better reflect what's
  happening.

- Replace completion usage with a flush_work() call.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
parent 8eb17dc1

kernel/backtracetest.c

+7 −11
Original line number Diff line number Diff line
@@ -21,24 +21,20 @@ static void backtrace_test_normal(void) 
	dump_stack();

}



static DECLARE_COMPLETION(backtrace_work);



static void backtrace_test_irq_callback(unsigned long data)

static void backtrace_test_bh_workfn(struct work_struct *work)

{

	dump_stack();

	complete(&backtrace_work);

}



static DECLARE_TASKLET_OLD(backtrace_tasklet, &backtrace_test_irq_callback);

static DECLARE_WORK(backtrace_bh_work, &backtrace_test_bh_workfn);



static void backtrace_test_irq(void)

static void backtrace_test_bh(void)

{

	pr_info("Testing a backtrace from irq context.\n");

	pr_info("Testing a backtrace from BH context.\n");

	pr_info("The following trace is a kernel self test and not a bug!\n");



	init_completion(&backtrace_work);

	tasklet_schedule(&backtrace_tasklet);

	wait_for_completion(&backtrace_work);

	queue_work(system_bh_wq, &backtrace_bh_work);

	flush_work(&backtrace_bh_work);

}



#ifdef CONFIG_STACKTRACE
@@ -65,7 +61,7 @@ static int backtrace_regression_test(void) 
	pr_info("====[ backtrace testing ]===========\n");



	backtrace_test_normal();

	backtrace_test_irq();

	backtrace_test_bh();

	backtrace_test_saved();



	pr_info("====[ end of backtrace testing ]====\n");