diff options
author | Steven Rostedt <srostedt@redhat.com> | 2009-05-07 14:20:28 -0400 |
---|---|---|
committer | Steven Rostedt <rostedt@goodmis.org> | 2009-05-07 14:20:28 -0400 |
commit | 0574ea421b90e0e45a72c447dd3c2c79ffd8c153 (patch) | |
tree | ec19f007794a8593f1c75f3f2d05c2471346298e /kernel/trace/ring_buffer_benchmark.c | |
parent | 65b77242043f74bca6a0d733c0e48ef03a8c9893 (diff) | |
download | linux-0574ea421b90e0e45a72c447dd3c2c79ffd8c153.tar.bz2 |
ring-buffer: only periodically call cond_resched to ring-buffer-benchmark
Calling cond_resched at every iteration of the loop adds a bit of
overhead to the benchmark.
This patch does two things.
1) only calls cond-resched when CONFIG_PREEMPT is not enabled
2) only calls cond-resched after so many traces has been performed.
[ Impact: less overhead to the ring-buffer-benchmark ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/ring_buffer_benchmark.c')
-rw-r--r-- | kernel/trace/ring_buffer_benchmark.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index f4ceb453c7dd..a7c048bb4466 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -218,16 +218,23 @@ static void ring_buffer_producer(void) } do_gettimeofday(&end_tv); - if (consumer && !(++cnt % wakeup_interval)) + cnt++; + if (consumer && !(cnt % wakeup_interval)) wake_up_process(consumer); +#ifndef CONFIG_PREEMPT /* * If we are a non preempt kernel, the 10 second run will * stop everything while it runs. Instead, we will call * cond_resched and also add any time that was lost by a * rescedule. + * + * Do a cond resched at the same frequency we would wake up + * the reader. */ - cond_resched(); + if (cnt % wakeup_interval) + cond_resched(); +#endif } while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test); pr_info("End ring buffer hammer\n"); |