diff options
| author | rwatson <rwatson@FreeBSD.org> | 2004-06-26 23:27:42 +0000 |
|---|---|---|
| committer | rwatson <rwatson@FreeBSD.org> | 2004-06-26 23:27:42 +0000 |
| commit | ddb1bad6a35a7a69ac921f84ecd8dd66c69b4415 (patch) | |
| tree | d6583006cb6461a59585bf7cbe82c1a5ee7d8039 /sys | |
| parent | 4c4f36d309ed95981307d49deb86788d8024cd7d (diff) | |
| download | FreeBSD-src-ddb1bad6a35a7a69ac921f84ecd8dd66c69b4415.zip FreeBSD-src-ddb1bad6a35a7a69ac921f84ecd8dd66c69b4415.tar.gz | |
The g_up and g_down threads use a local 'mymutex' mutex to allow WITNESS
to warn about attempts to sleep in the I/O path. This change pushes the
definition and use of 'mymutex' behind #ifdef WITNESS to avoid the cost
in non-debugging cases. This results in a clear .22% performance win for
512 byte and 1k I/O tests on my SMP test box. Not much, but every bit
counts.
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/geom/geom_io.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/sys/geom/geom_io.c b/sys/geom/geom_io.c index 7b5b115..19d5de7 100644 --- a/sys/geom/geom_io.c +++ b/sys/geom/geom_io.c @@ -315,10 +315,12 @@ g_io_schedule_down(struct thread *tp __unused) struct bio *bp; off_t excess; int error; +#ifdef WITNESS struct mtx mymutex; bzero(&mymutex, sizeof mymutex); mtx_init(&mymutex, "g_xdown", NULL, MTX_DEF); +#endif for(;;) { g_bioq_lock(&g_bio_run_down); @@ -357,9 +359,13 @@ g_io_schedule_down(struct thread *tp __unused) default: break; } +#ifdef WITNESS mtx_lock(&mymutex); +#endif bp->bio_to->geom->start(bp); +#ifdef WITNESS mtx_unlock(&mymutex); +#endif } } @@ -384,26 +390,36 @@ void g_io_schedule_up(struct thread *tp __unused) { struct bio *bp; +#ifdef WITNESS struct mtx mymutex; bzero(&mymutex, sizeof mymutex); mtx_init(&mymutex, "g_xup", NULL, MTX_DEF); +#endif for(;;) { g_bioq_lock(&g_bio_run_up); bp = g_bioq_first(&g_bio_run_task); if (bp != NULL) { g_bioq_unlock(&g_bio_run_up); +#ifdef WITNESS mtx_lock(&mymutex); +#endif bp->bio_task(bp->bio_task_arg); +#ifdef WITNESS mtx_unlock(&mymutex); +#endif continue; } bp = g_bioq_first(&g_bio_run_up); if (bp != NULL) { g_bioq_unlock(&g_bio_run_up); +#ifdef WITNESS mtx_lock(&mymutex); +#endif biodone(bp); +#ifdef WITNESS mtx_unlock(&mymutex); +#endif continue; } msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, |
