Wake up log waiters in gfs2_log_release when log space has actually become
available. This is a much better place for the wakeup than gfs2_logd.
Check if enough log space is immeditely available before anything else. If
there isn't, use io_wait_event to wait instead of open coding it.
Signed-off-by: Andreas Gruenbacher <agrue...@redhat.com>
---
fs/gfs2/log.c | 58 ++++++++++++++++++++++-----------------------------
1 file changed, 25 insertions(+), 33 deletions(-)
diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index a8cc71ba4852..36dbec4f9a54 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -411,6 +411,8 @@ void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int
blks)
trace_gfs2_log_blocks(sdp, blks);
gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
sdp->sd_jdesc->jd_blocks);
+ if (atomic_read(&sdp->sd_log_blks_needed))
+ wake_up(&sdp->sd_log_waitq);
}
/**
@@ -444,37 +446,34 @@ void gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int
blks)
{
unsigned reserved_blks = 7 * (4096 / sdp->sd_vfs->s_blocksize);
unsigned wanted = blks + reserved_blks;
- DEFINE_WAIT(wait);
- int did_wait = 0;
unsigned int free_blocks;
- atomic_add(blks, &sdp->sd_log_blks_needed);
-retry:
free_blocks = atomic_read(&sdp->sd_log_blks_free);
- if (unlikely(free_blocks <= wanted)) {
- do {
- prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
- TASK_UNINTERRUPTIBLE);
- wake_up(&sdp->sd_logd_waitq);
- did_wait = 1;
- if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
- io_schedule();
- free_blocks = atomic_read(&sdp->sd_log_blks_free);
- } while(free_blocks <= wanted);
- finish_wait(&sdp->sd_log_waitq, &wait);
+ while (free_blocks >= wanted) {
+ if (atomic_try_cmpxchg(&sdp->sd_log_blks_free, &free_blocks,
+ free_blocks - blks))
+ return;
}
- if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
- free_blocks - blks) != free_blocks)
- goto retry;
- atomic_sub(blks, &sdp->sd_log_blks_needed);
- trace_gfs2_log_blocks(sdp, -blks);
- /*
- * If we waited, then so might others, wake them up _after_ we get
- * our share of the log.
- */
- if (unlikely(did_wait))
- wake_up(&sdp->sd_log_waitq);
+ atomic_add(blks, &sdp->sd_log_blks_needed);
+ for (;;) {
+ if (current != sdp->sd_logd_process)
+ wake_up(&sdp->sd_logd_waitq);
+ io_wait_event(sdp->sd_log_waitq,
+ (free_blocks = atomic_read(&sdp->sd_log_blks_free),
+ free_blocks >= wanted));
+ do {
+ if (atomic_try_cmpxchg(&sdp->sd_log_blks_free,
+ &free_blocks,
+ free_blocks - blks)) {
+ trace_gfs2_log_blocks(sdp, -blks);
+ if (atomic_sub_return(blks,
+ &sdp->sd_log_blks_needed))
+ wake_up(&sdp->sd_log_waitq);
+ return;
+ }
+ } while (free_blocks >= wanted);
+ }
}
/**
@@ -1190,7 +1189,6 @@ int gfs2_logd(void *data)
struct gfs2_sbd *sdp = data;
unsigned long t = 1;
DEFINE_WAIT(wait);
- bool did_flush;
while (!kthread_should_stop()) {
@@ -1209,12 +1207,10 @@ int gfs2_logd(void *data)
continue;
}
- did_flush = false;
if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
gfs2_ail1_empty(sdp, 0);
gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
GFS2_LFC_LOGD_JFLUSH_REQD);
- did_flush = true;
}
if (gfs2_ail_flush_reqd(sdp)) {
@@ -1223,12 +1219,8 @@ int gfs2_logd(void *data)
gfs2_ail1_empty(sdp, 0);
gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
GFS2_LFC_LOGD_AIL_FLUSH_REQD);
- did_flush = true;
}
- if (!gfs2_ail_flush_reqd(sdp) || did_flush)
- wake_up(&sdp->sd_log_waitq);
-
t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
try_to_freeze();
--
2.26.2
