From f3708fb59f6c2498e8ec4f29010375f600b68642 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Sun, 13 Dec 2020 09:21:34 +0100 Subject: gfs2: Get rid of sd_reserving_log This counter and the associated wait queue are only used so that gfs2_make_fs_ro can efficiently wait for all pending log space allocations to fail after setting the filesystem to read-only. This comes at the cost of waking up that wait queue very frequently. Instead, when gfs2_log_reserve fails because the filesystem has become read-only, Wake up sd_log_waitq. In gfs2_make_fs_ro, set the file system read-only and then wait until all the log space has been released. Give up and report the problem after a while. With that, sd_reserving_log and sd_reserving_log_wait can be removed. Signed-off-by: Andreas Gruenbacher --- fs/gfs2/incore.h | 3 --- fs/gfs2/log.c | 17 ++++++++++------- fs/gfs2/log.h | 1 + fs/gfs2/ops_fstype.c | 2 -- fs/gfs2/super.c | 12 ++++++------ fs/gfs2/trans.c | 2 ++ 6 files changed, 19 insertions(+), 18 deletions(-) diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index c3f6dd378b10..8f8676cf72ed 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -849,9 +849,6 @@ struct gfs2_sbd { int sd_log_error; /* First log error */ wait_queue_head_t sd_withdraw_wait; - atomic_t sd_reserving_log; - wait_queue_head_t sd_reserving_log_wait; - unsigned int sd_log_flush_head; spinlock_t sd_ail_lock; diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index 0fceb60907a2..0da05492e8b8 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -397,6 +397,15 @@ static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail) spin_unlock(&sdp->sd_ail_lock); } +/** + * gfs2_log_is_empty - Check if the log is empty + * @sdp: The GFS2 superblock + */ + +bool gfs2_log_is_empty(struct gfs2_sbd *sdp) { + return atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks; +} + /** * gfs2_log_release - Release a given number of log blocks * @sdp: The GFS2 superblock @@ -461,13 +470,9 @@ retry: } while(free_blocks <= wanted); finish_wait(&sdp->sd_log_waitq, &wait); } - atomic_inc(&sdp->sd_reserving_log); if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks, - free_blocks - blks) != free_blocks) { - if (atomic_dec_and_test(&sdp->sd_reserving_log)) - wake_up(&sdp->sd_reserving_log_wait); + free_blocks - blks) != free_blocks) goto retry; - } atomic_sub(blks, &sdp->sd_log_blks_needed); trace_gfs2_log_blocks(sdp, -blks); @@ -483,8 +488,6 @@ retry: gfs2_log_release(sdp, blks); ret = -EROFS; } - if (atomic_dec_and_test(&sdp->sd_reserving_log)) - wake_up(&sdp->sd_reserving_log_wait); return ret; } diff --git a/fs/gfs2/log.h b/fs/gfs2/log.h index a9cdbc990edf..16efbe614279 100644 --- a/fs/gfs2/log.h +++ b/fs/gfs2/log.h @@ -64,6 +64,7 @@ static inline void gfs2_ordered_add_inode(struct gfs2_inode *ip) extern void gfs2_ordered_del_inode(struct gfs2_inode *ip); extern unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct); extern void gfs2_remove_from_ail(struct gfs2_bufdata *bd); +extern bool gfs2_log_is_empty(struct gfs2_sbd *sdp); extern void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks); extern int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks); extern void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd, diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 61fce59cb4d3..986dc2ebebf0 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -136,8 +136,6 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb) init_rwsem(&sdp->sd_log_flush_lock); atomic_set(&sdp->sd_log_in_flight, 0); - atomic_set(&sdp->sd_reserving_log, 0); - init_waitqueue_head(&sdp->sd_reserving_log_wait); init_waitqueue_head(&sdp->sd_log_flush_wait); atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN); mutex_init(&sdp->sd_freeze_mutex); diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index ed7a829e9ffe..f188277f7d48 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -645,13 +645,13 @@ int gfs2_make_fs_ro(struct gfs2_sbd *sdp) gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SHUTDOWN | GFS2_LFC_MAKE_FS_RO); - wait_event(sdp->sd_reserving_log_wait, - atomic_read(&sdp->sd_reserving_log) == 0); - gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == - sdp->sd_jdesc->jd_blocks); + wait_event_timeout(sdp->sd_log_waitq, + gfs2_log_is_empty(sdp), + HZ * 5); + gfs2_assert_warn(sdp, gfs2_log_is_empty(sdp)); } else { - wait_event_timeout(sdp->sd_reserving_log_wait, - atomic_read(&sdp->sd_reserving_log) == 0, + wait_event_timeout(sdp->sd_log_waitq, + gfs2_log_is_empty(sdp), HZ * 5); } if (gfs2_holder_initialized(&freeze_gh)) diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c index db29ca253853..aefe450e009e 100644 --- a/fs/gfs2/trans.c +++ b/fs/gfs2/trans.c @@ -71,6 +71,8 @@ int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp, error = gfs2_log_reserve(sdp, tr->tr_reserved); if (error) { sb_end_intwrite(sdp->sd_vfs); + if (error == -EROFS) + wake_up(&sdp->sd_log_waitq); return error; } -- cgit v1.2.3