| Message ID | 1433516477-5153-16-git-send-email-pmladek@suse.cz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 5 Jun 2015 17:01:14 +0200 Petr Mladek <pmladek@suse.cz> wrote: > It takes a while until the ring_buffer_benchmark module is removed > when the ring buffer hammer is running. It is because it takes > few seconds and kthread_should_terminate() is not being checked. > > This patch adds the check for kthread termination into the producer. > It uses the existing kill_test flag to finish the kthreads as > cleanly as possible. > > It disables printing the "ERROR" message when the kthread is going. > > Also it makes sure that producer does not go into the 10sec sleep > when it is being killed. This patch looks like something I may take regardless of the other patches (if it applies cleanly). As for the other patches, the ring buffer benchmark is just that, a benchmark that I use when making changes to the ring buffer. It's not something for production systems. What about just adding a depend on !LIVE_PATCHING to RING_BUFFER_BENCHMARK, or force it to shut down during patching. There's no reason to make it safe to be running when you patch the kernel. Just adds complexity to some simple code. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index 2d276b892aea..4ecf7c4567e2 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -270,6 +270,9 @@ static void ring_buffer_producer(void) try_to_freeze(); } + if (kthread_should_stop()) + kill_test = 1; + } while (ktime_before(end_time, timeout) && !kill_test); trace_printk("End ring buffer hammer\n"); @@ -291,7 +294,7 @@ static void ring_buffer_producer(void) entries = ring_buffer_entries(buffer); overruns = ring_buffer_overruns(buffer); - if (kill_test) + if (kill_test && !kthread_should_stop()) trace_printk("ERROR!\n"); if (!disable_reader) { @@ -377,10 +380,8 @@ static void ring_buffer_producer_thread_init(void *arg) static void ring_buffer_producer_thread_func(void *arg) { - if (kill_test) { - set_kthread_iterant_int_sleep(); - return; - } + if (kill_test) + goto test_killed; ring_buffer_reset(buffer); @@ -393,9 +394,16 @@ static void ring_buffer_producer_thread_func(void *arg) ring_buffer_producer(); + if (kill_test) + goto test_killed; + trace_printk("Sleeping for 10 secs\n"); set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(HZ * SLEEP_TIME); + return; + +test_killed: + set_kthread_iterant_int_sleep(); } static int __init ring_buffer_benchmark_init(void)
It takes a while until the ring_buffer_benchmark module is removed when the ring buffer hammer is running. It is because it takes few seconds and kthread_should_terminate() is not being checked. This patch adds the check for kthread termination into the producer. It uses the existing kill_test flag to finish the kthreads as cleanly as possible. It disables printing the "ERROR" message when the kthread is going. Also it makes sure that producer does not go into the 10sec sleep when it is being killed. Signed-off-by: Petr Mladek <pmladek@suse.cz> --- kernel/trace/ring_buffer_benchmark.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)