From 5ae8fff8d031b5728f4c0e36e971bba42bb78bea Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Sun, 13 Dec 2020 11:37:17 +0100 Subject: gfs2: Clean up gfs2_log_reserve 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 --- fs/gfs2/log.c | 58 +++++++++++++++++++++++++-------------------------------- fs/gfs2/trans.c | 3 +-- 2 files changed, 26 insertions(+), 35 deletions(-) (limited to 'fs/gfs2') diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index cff95889b6f4..ca9fa481913d 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -415,11 +415,12 @@ bool gfs2_log_is_empty(struct gfs2_sbd *sdp) { void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) { - atomic_add(blks, &sdp->sd_log_blks_free); 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); } /** @@ -444,36 +445,33 @@ 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); + while (free_blocks >= wanted) { + if (atomic_try_cmpxchg(&sdp->sd_log_blks_free, &free_blocks, + free_blocks - blks)) + return; + } + + atomic_add(blks, &sdp->sd_log_blks_needed); + for (;;) { + if (current != sdp->sd_logd_process) 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); + 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)) + goto reserved; + } while (free_blocks >= wanted); } - 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)) +reserved: + trace_gfs2_log_blocks(sdp, -blks); + if (atomic_sub_return(blks, &sdp->sd_log_blks_needed)) wake_up(&sdp->sd_log_waitq); } @@ -1107,7 +1105,8 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr) maxres = sdp->sd_log_blks_reserved + tr->tr_reserved; gfs2_assert_withdraw(sdp, maxres >= reserved); unused = maxres - reserved; - gfs2_log_release(sdp, unused); + if (unused) + gfs2_log_release(sdp, unused); sdp->sd_log_blks_reserved = reserved; gfs2_log_unlock(sdp); @@ -1192,7 +1191,6 @@ int gfs2_logd(void *data) struct gfs2_sbd *sdp = data; unsigned long t = 1; DEFINE_WAIT(wait); - bool did_flush; while (!kthread_should_stop()) { @@ -1211,12 +1209,10 @@ 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)) { @@ -1225,12 +1221,8 @@ 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(); diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c index 2269aa7ad69d..cac93b2004cf 100644 --- a/fs/gfs2/trans.c +++ b/fs/gfs2/trans.c @@ -73,10 +73,9 @@ int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp, down_read(&sdp->sd_log_flush_lock); if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) { - gfs2_log_release(sdp, tr->tr_reserved); up_read(&sdp->sd_log_flush_lock); + gfs2_log_release(sdp, tr->tr_reserved); sb_end_intwrite(sdp->sd_vfs); - wake_up(&sdp->sd_log_waitq); return -EROFS; } -- cgit v1.2.3