Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Again fix race between zil_commit() and zil_suspend(). #14979

Merged
merged 1 commit into from
Jun 30, 2023
Merged

Again fix race between zil_commit() and zil_suspend(). #14979

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
36 changes: 28 additions & 8 deletions module/zfs/zil.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -794,8 +794,8 @@ zil_free_lwb(zilog_t *zilog, lwb_t *lwb)
{
ASSERT(MUTEX_HELD(&zilog->zl_lock));
ASSERT(!MUTEX_HELD(&lwb->lwb_vdev_lock));
ASSERT(list_is_empty(&lwb->lwb_waiters));
ASSERT(list_is_empty(&lwb->lwb_itxs));
VERIFY(list_is_empty(&lwb->lwb_waiters));
VERIFY(list_is_empty(&lwb->lwb_itxs));
ASSERT(avl_is_empty(&lwb->lwb_vdev_tree));
ASSERT3P(lwb->lwb_write_zio, ==, NULL);
ASSERT3P(lwb->lwb_root_zio, ==, NULL);
Expand Down Expand Up @@ -2521,10 +2521,10 @@ zil_clean(zilog_t *zilog, uint64_t synced_txg)
* This function will traverse the queue of itxs that need to be
* committed, and move them onto the ZIL's zl_itx_commit_list.
*/
static void
static uint64_t
zil_get_commit_list(zilog_t *zilog)
{
uint64_t otxg, txg;
uint64_t otxg, txg, wtxg = 0;
list_t *commit_list = &zilog->zl_itx_commit_list;

ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
Expand Down Expand Up @@ -2558,10 +2558,22 @@ zil_get_commit_list(zilog_t *zilog)
*/
ASSERT(zilog_is_dirty_in_txg(zilog, txg) ||
spa_freeze_txg(zilog->zl_spa) != UINT64_MAX);
list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list);
list_t *sync_list = &itxg->itxg_itxs->i_sync_list;
if (unlikely(zilog->zl_suspend > 0)) {
/*
* ZIL was just suspended, but we lost the race.
* Allow all earlier itxs to be committed, but ask
* caller to do txg_wait_synced(txg) for any new.
*/
if (!list_is_empty(sync_list))
wtxg = MAX(wtxg, txg);
} else {
list_move_tail(commit_list, sync_list);
}

mutex_exit(&itxg->itxg_lock);
}
return (wtxg);
}

/*
Expand Down Expand Up @@ -2949,11 +2961,12 @@ zil_process_commit_list(zilog_t *zilog, zil_commit_waiter_t *zcw, list_t *ilwbs)
* not issued, we rely on future calls to zil_commit_writer() to issue
* the lwb, or the timeout mechanism found in zil_commit_waiter().
*/
static void
static uint64_t
zil_commit_writer(zilog_t *zilog, zil_commit_waiter_t *zcw)
{
list_t ilwbs;
lwb_t *lwb;
uint64_t wtxg = 0;

ASSERT(!MUTEX_HELD(&zilog->zl_lock));
ASSERT(spa_writeable(zilog->zl_spa));
Expand Down Expand Up @@ -2983,7 +2996,7 @@ zil_commit_writer(zilog_t *zilog, zil_commit_waiter_t *zcw)

ZIL_STAT_BUMP(zilog, zil_commit_writer_count);

zil_get_commit_list(zilog);
wtxg = zil_get_commit_list(zilog);
zil_prune_commit_list(zilog);
zil_process_commit_list(zilog, zcw, &ilwbs);

Expand All @@ -2992,6 +3005,7 @@ zil_commit_writer(zilog_t *zilog, zil_commit_waiter_t *zcw)
while ((lwb = list_remove_head(&ilwbs)) != NULL)
zil_lwb_write_issue(zilog, lwb);
list_destroy(&ilwbs);
return (wtxg);
}

static void
Expand Down Expand Up @@ -3507,7 +3521,7 @@ zil_commit_impl(zilog_t *zilog, uint64_t foid)
zil_commit_waiter_t *zcw = zil_alloc_commit_waiter();
zil_commit_itx_assign(zilog, zcw);

zil_commit_writer(zilog, zcw);
uint64_t wtxg = zil_commit_writer(zilog, zcw);
zil_commit_waiter(zilog, zcw);

if (zcw->zcw_zio_error != 0) {
Expand All @@ -3522,6 +3536,8 @@ zil_commit_impl(zilog_t *zilog, uint64_t foid)
DTRACE_PROBE2(zil__commit__io__error,
zilog_t *, zilog, zil_commit_waiter_t *, zcw);
txg_wait_synced(zilog->zl_dmu_pool, 0);
} else if (wtxg != 0) {
txg_wait_synced(zilog->zl_dmu_pool, wtxg);
}

zil_free_commit_waiter(zcw);
Expand Down Expand Up @@ -3901,11 +3917,13 @@ zil_suspend(const char *osname, void **cookiep)
return (error);
zilog = dmu_objset_zil(os);

mutex_enter(&zilog->zl_issuer_lock);
mutex_enter(&zilog->zl_lock);
zh = zilog->zl_header;

if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */
mutex_exit(&zilog->zl_lock);
mutex_exit(&zilog->zl_issuer_lock);
dmu_objset_rele(os, suspend_tag);
return (SET_ERROR(EBUSY));
}
Expand All @@ -3919,6 +3937,7 @@ zil_suspend(const char *osname, void **cookiep)
if (cookiep == NULL && !zilog->zl_suspending &&
(zilog->zl_suspend > 0 || BP_IS_HOLE(&zh->zh_log))) {
mutex_exit(&zilog->zl_lock);
mutex_exit(&zilog->zl_issuer_lock);
dmu_objset_rele(os, suspend_tag);
return (0);
}
Expand All @@ -3927,6 +3946,7 @@ zil_suspend(const char *osname, void **cookiep)
dsl_pool_rele(dmu_objset_pool(os), suspend_tag);

zilog->zl_suspend++;
mutex_exit(&zilog->zl_issuer_lock);

if (zilog->zl_suspend > 1) {
/*
Expand Down