From ecd49f7a36fbccc884471f86fc43de6ca8d1f786 Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <djwong@kernel.org>
Date: Mon, 11 Sep 2023 08:39:02 -0700
Subject: [PATCH 1/4] xfs: fix per-cpu CIL structure aggregation racing with
dying cpus
In commit 7c8ade2121200 ("xfs: implement percpu cil space used
calculation"), the XFS committed (log) item list code was converted to
use per-cpu lists and space tracking to reduce cpu contention when
multiple threads are modifying different parts of the filesystem and
hence end up contending on the log structures during transaction commit.
Each CPU tracks its own commit items and space usage, and these do not
have to be merged into the main CIL until either someone wants to push
the CIL items, or we run over a soft threshold and switch to slower (but
more accurate) accounting with atomics.
Unfortunately, the for_each_cpu iteration suffers from the same race
with cpu dying problem that was identified in commit 8b57b11cca88f
("pcpcntrs: fix dying cpu summation race") -- CPUs are removed from
cpu_online_mask before the CPUHP_XFS_DEAD callback gets called. As a
result, both CIL percpu structure aggregation functions fail to collect
the items and accounted space usage at the correct point in time.
If we're lucky, the items that are collected from the online cpus exceed
the space given to those cpus, and the log immediately shuts down in
xlog_cil_insert_items due to the (apparent) log reservation overrun.
This happens periodically with generic/650, which exercises cpu hotplug
vs. the filesystem code:
smpboot: CPU 3 is now offline
XFS (sda3): ctx ticket reservation ran out. Need to up reservation
XFS (sda3): ticket reservation summary:
XFS (sda3): unit res = 9268 bytes
XFS (sda3): current res = -40 bytes
XFS (sda3): original count = 1
XFS (sda3): remaining count = 1
XFS (sda3): Filesystem has been shut down due to log error (0x2).
Applying the same sort of fix from 8b57b11cca88f to the CIL code seems
to make the generic/650 problem go away, but I've been told that tglx
was not happy when he saw:
"...the only thing we actually need to care about is that
percpu_counter_sum() iterates dying CPUs. That's trivial to do, and when
there are no CPUs dying, it has no addition overhead except for a
cpumask_or() operation."
The CPU hotplug code is rather complex and difficult to understand and I
don't want to try to understand the cpu hotplug locking well enough to
use cpu_dying mask. Furthermore, there's a performance improvement that
could be had here. Attach a private cpu mask to the CIL structure so
that we can track exactly which cpus have accessed the percpu data at
all. It doesn't matter if the cpu has since gone offline; log item
aggregation will still find the items. Better yet, we skip cpus that
have not recently logged anything.
Worse yet, Ritesh Harjani and Eric Sandeen both reported today that CPU
hot remove racing with an xfs mount can crash if the cpu_dead notifier
tries to access the log but the mount hasn't yet set up the log.
Link: https://lore.kernel.org/linux-xfs/ZOLzgBOuyWHapOyZ@dread.disaster.area/T/
Link: https://lore.kernel.org/lkml/877cuj1mt1.ffs@tglx/
Link: https://lore.kernel.org/lkml/20230414162755.281993820@linutronix.de/
Link: https://lore.kernel.org/linux-xfs/ZOVkjxWZq0YmjrJu@dread.disaster.area/T/
Cc: tglx@linutronix.de
Cc: peterz@infradead.org
Reported-by: ritesh.list@gmail.com
Reported-by: sandeen@sandeen.net
Fixes: af1c2146a50b ("xfs: introduce per-cpu CIL tracking structure")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_log_cil.c | 52 +++++++++++++------------------------------
fs/xfs/xfs_log_priv.h | 14 +++++-------
fs/xfs/xfs_super.c | 1 -
3 files changed, 22 insertions(+), 45 deletions(-)
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c
index eccbfb99e894..ebc70aaa299c 100644
--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -124,7 +124,7 @@ xlog_cil_push_pcp_aggregate(
struct xlog_cil_pcp *cilpcp;
int cpu;
- for_each_online_cpu(cpu) {
+ for_each_cpu(cpu, &ctx->cil_pcpmask) {
cilpcp = per_cpu_ptr(cil->xc_pcp, cpu);
ctx->ticket->t_curr_res += cilpcp->space_reserved;
@@ -165,7 +165,13 @@ xlog_cil_insert_pcp_aggregate(
if (!test_and_clear_bit(XLOG_CIL_PCP_SPACE, &cil->xc_flags))
return;
- for_each_online_cpu(cpu) {
+ /*
+ * We can race with other cpus setting cil_pcpmask. However, we've
+ * atomically cleared PCP_SPACE which forces other threads to add to
+ * the global space used count. cil_pcpmask is a superset of cilpcp
+ * structures that could have a nonzero space_used.
+ */
+ for_each_cpu(cpu, &ctx->cil_pcpmask) {
int old, prev;
cilpcp = per_cpu_ptr(cil->xc_pcp, cpu);
@@ -554,6 +560,7 @@ xlog_cil_insert_items(
int iovhdr_res = 0, split_res = 0, ctx_res = 0;
int space_used;
int order;
+ unsigned int cpu_nr;
struct xlog_cil_pcp *cilpcp;
ASSERT(tp);
@@ -577,7 +584,12 @@ xlog_cil_insert_items(
* can't be scheduled away between split sample/update operations that
* are done without outside locking to serialise them.
*/
- cilpcp = get_cpu_ptr(cil->xc_pcp);
+ cpu_nr = get_cpu();
+ cilpcp = this_cpu_ptr(cil->xc_pcp);
+
+ /* Tell the future push that there was work added by this CPU. */
+ if (!cpumask_test_cpu(cpu_nr, &ctx->cil_pcpmask))
+ cpumask_test_and_set_cpu(cpu_nr, &ctx->cil_pcpmask);
/*
* We need to take the CIL checkpoint unit reservation on the first
@@ -663,7 +675,7 @@ xlog_cil_insert_items(
continue;
list_add_tail(&lip->li_cil, &cilpcp->log_items);
}
- put_cpu_ptr(cilpcp);
+ put_cpu();
/*
* If we've overrun the reservation, dump the tx details before we move
@@ -1790,38 +1802,6 @@ out_shutdown:
return 0;
}
-/*
- * Move dead percpu state to the relevant CIL context structures.
- *
- * We have to lock the CIL context here to ensure that nothing is modifying
- * the percpu state, either addition or removal. Both of these are done under
- * the CIL context lock, so grabbing that exclusively here will ensure we can
- * safely drain the cilpcp for the CPU that is dying.
- */
-void
-xlog_cil_pcp_dead(
- struct xlog *log,
- unsigned int cpu)
-{
- struct xfs_cil *cil = log->l_cilp;
- struct xlog_cil_pcp *cilpcp = per_cpu_ptr(cil->xc_pcp, cpu);
- struct xfs_cil_ctx *ctx;
-
- down_write(&cil->xc_ctx_lock);
- ctx = cil->xc_ctx;
- if (ctx->ticket)
- ctx->ticket->t_curr_res += cilpcp->space_reserved;
- cilpcp->space_reserved = 0;
-
- if (!list_empty(&cilpcp->log_items))
- list_splice_init(&cilpcp->log_items, &ctx->log_items);
- if (!list_empty(&cilpcp->busy_extents))
- list_splice_init(&cilpcp->busy_extents, &ctx->busy_extents);
- atomic_add(cilpcp->space_used, &ctx->space_used);
- cilpcp->space_used = 0;
- up_write(&cil->xc_ctx_lock);
-}
-
/*
* Perform initial CIL structure initialisation.
*/
diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index 1bd2963e8fbd..af87648331d5 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -231,6 +231,12 @@ struct xfs_cil_ctx {
struct work_struct discard_endio_work;
struct work_struct push_work;
atomic_t order_id;
+
+ /*
+ * CPUs that could have added items to the percpu CIL data. Access is
+ * coordinated with xc_ctx_lock.
+ */
+ struct cpumask cil_pcpmask;
};
/*
@@ -278,9 +284,6 @@ struct xfs_cil {
wait_queue_head_t xc_push_wait; /* background push throttle */
void __percpu *xc_pcp; /* percpu CIL structures */
-#ifdef CONFIG_HOTPLUG_CPU
- struct list_head xc_pcp_list;
-#endif
} ____cacheline_aligned_in_smp;
/* xc_flags bit values */
@@ -705,9 +708,4 @@ xlog_kvmalloc(
return p;
}
-/*
- * CIL CPU dead notifier
- */
-void xlog_cil_pcp_dead(struct xlog *log, unsigned int cpu);
-
#endif /* __XFS_LOG_PRIV_H__ */
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 1f77014c6e1a..ed29a5022e36 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -2337,7 +2337,6 @@ xfs_cpu_dead(
list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
spin_unlock(&xfs_mount_list_lock);
xfs_inodegc_cpu_dead(mp, cpu);
- xlog_cil_pcp_dead(mp->m_log, cpu);
spin_lock(&xfs_mount_list_lock);
}
spin_unlock(&xfs_mount_list_lock);
From 62334fab47621dd91ab30dd5bb6c43d78a8ec279 Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <djwong@kernel.org>
Date: Mon, 11 Sep 2023 08:39:03 -0700
Subject: [PATCH 2/4] xfs: use per-mount cpumask to track nonempty percpu
inodegc lists
Directly track which CPUs have contributed to the inodegc percpu lists
instead of trusting the cpu online mask. This eliminates a theoretical
problem where the inodegc flush functions might fail to flush a CPU's
inodes if that CPU happened to be dying at exactly the same time. Most
likely nobody's noticed this because the CPU dead hook moves the percpu
inodegc list to another CPU and schedules that worker immediately. But
it's quite possible that this is a subtle race leading to UAF if the
inodegc flush were part of an unmount.
Further benefits: This reduces the overhead of the inodegc flush code
slightly by allowing us to ignore CPUs that have empty lists. Better
yet, it reduces our dependence on the cpu online masks, which have been
the cause of confusion and drama lately.
Fixes: ab23a7768739 ("xfs: per-cpu deferred inode inactivation queues")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_icache.c | 78 ++++++++++++++++-----------------------------
fs/xfs/xfs_icache.h | 1 -
fs/xfs/xfs_mount.h | 6 ++--
fs/xfs/xfs_super.c | 4 +--
4 files changed, 33 insertions(+), 56 deletions(-)
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index e541f5c0bc25..30d7454a9b93 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -443,7 +443,7 @@ xfs_inodegc_queue_all(
int cpu;
bool ret = false;
- for_each_online_cpu(cpu) {
+ for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
gc = per_cpu_ptr(mp->m_inodegc, cpu);
if (!llist_empty(&gc->list)) {
mod_delayed_work_on(cpu, mp->m_inodegc_wq, &gc->work, 0);
@@ -463,7 +463,7 @@ xfs_inodegc_wait_all(
int error = 0;
flush_workqueue(mp->m_inodegc_wq);
- for_each_online_cpu(cpu) {
+ for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
struct xfs_inodegc *gc;
gc = per_cpu_ptr(mp->m_inodegc, cpu);
@@ -1845,9 +1845,17 @@ xfs_inodegc_worker(
struct xfs_inodegc, work);
struct llist_node *node = llist_del_all(&gc->list);
struct xfs_inode *ip, *n;
+ struct xfs_mount *mp = gc->mp;
unsigned int nofs_flag;
- ASSERT(gc->cpu == smp_processor_id());
+ /*
+ * Clear the cpu mask bit and ensure that we have seen the latest
+ * update of the gc structure associated with this CPU. This matches
+ * with the release semantics used when setting the cpumask bit in
+ * xfs_inodegc_queue.
+ */
+ cpumask_clear_cpu(gc->cpu, &mp->m_inodegc_cpumask);
+ smp_mb__after_atomic();
WRITE_ONCE(gc->items, 0);
@@ -1862,7 +1870,7 @@ xfs_inodegc_worker(
nofs_flag = memalloc_nofs_save();
ip = llist_entry(node, struct xfs_inode, i_gclist);
- trace_xfs_inodegc_worker(ip->i_mount, READ_ONCE(gc->shrinker_hits));
+ trace_xfs_inodegc_worker(mp, READ_ONCE(gc->shrinker_hits));
WRITE_ONCE(gc->shrinker_hits, 0);
llist_for_each_entry_safe(ip, n, node, i_gclist) {
@@ -2057,6 +2065,7 @@ xfs_inodegc_queue(
struct xfs_inodegc *gc;
int items;
unsigned int shrinker_hits;
+ unsigned int cpu_nr;
unsigned long queue_delay = 1;
trace_xfs_inode_set_need_inactive(ip);
@@ -2064,18 +2073,28 @@ xfs_inodegc_queue(
ip->i_flags |= XFS_NEED_INACTIVE;
spin_unlock(&ip->i_flags_lock);
- gc = get_cpu_ptr(mp->m_inodegc);
+ cpu_nr = get_cpu();
+ gc = this_cpu_ptr(mp->m_inodegc);
llist_add(&ip->i_gclist, &gc->list);
items = READ_ONCE(gc->items);
WRITE_ONCE(gc->items, items + 1);
shrinker_hits = READ_ONCE(gc->shrinker_hits);
+ /*
+ * Ensure the list add is always seen by anyone who finds the cpumask
+ * bit set. This effectively gives the cpumask bit set operation
+ * release ordering semantics.
+ */
+ smp_mb__before_atomic();
+ if (!cpumask_test_cpu(cpu_nr, &mp->m_inodegc_cpumask))
+ cpumask_test_and_set_cpu(cpu_nr, &mp->m_inodegc_cpumask);
+
/*
* We queue the work while holding the current CPU so that the work
* is scheduled to run on this CPU.
*/
if (!xfs_is_inodegc_enabled(mp)) {
- put_cpu_ptr(gc);
+ put_cpu();
return;
}
@@ -2085,7 +2104,7 @@ xfs_inodegc_queue(
trace_xfs_inodegc_queue(mp, __return_address);
mod_delayed_work_on(current_cpu(), mp->m_inodegc_wq, &gc->work,
queue_delay);
- put_cpu_ptr(gc);
+ put_cpu();
if (xfs_inodegc_want_flush_work(ip, items, shrinker_hits)) {
trace_xfs_inodegc_throttle(mp, __return_address);
@@ -2093,47 +2112,6 @@ xfs_inodegc_queue(
}
}
-/*
- * Fold the dead CPU inodegc queue into the current CPUs queue.
- */
-void
-xfs_inodegc_cpu_dead(
- struct xfs_mount *mp,
- unsigned int dead_cpu)
-{
- struct xfs_inodegc *dead_gc, *gc;
- struct llist_node *first, *last;
- unsigned int count = 0;
-
- dead_gc = per_cpu_ptr(mp->m_inodegc, dead_cpu);
- cancel_delayed_work_sync(&dead_gc->work);
-
- if (llist_empty(&dead_gc->list))
- return;
-
- first = dead_gc->list.first;
- last = first;
- while (last->next) {
- last = last->next;
- count++;
- }
- dead_gc->list.first = NULL;
- dead_gc->items = 0;
-
- /* Add pending work to current CPU */
- gc = get_cpu_ptr(mp->m_inodegc);
- llist_add_batch(first, last, &gc->list);
- count += READ_ONCE(gc->items);
- WRITE_ONCE(gc->items, count);
-
- if (xfs_is_inodegc_enabled(mp)) {
- trace_xfs_inodegc_queue(mp, __return_address);
- mod_delayed_work_on(current_cpu(), mp->m_inodegc_wq, &gc->work,
- 0);
- }
- put_cpu_ptr(gc);
-}
-
/*
* We set the inode flag atomically with the radix tree tag. Once we get tag
* lookups on the radix tree, this inode flag can go away.
@@ -2195,7 +2173,7 @@ xfs_inodegc_shrinker_count(
if (!xfs_is_inodegc_enabled(mp))
return 0;
- for_each_online_cpu(cpu) {
+ for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
gc = per_cpu_ptr(mp->m_inodegc, cpu);
if (!llist_empty(&gc->list))
return XFS_INODEGC_SHRINKER_COUNT;
@@ -2220,7 +2198,7 @@ xfs_inodegc_shrinker_scan(
trace_xfs_inodegc_shrinker_scan(mp, sc, __return_address);
- for_each_online_cpu(cpu) {
+ for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
gc = per_cpu_ptr(mp->m_inodegc, cpu);
if (!llist_empty(&gc->list)) {
unsigned int h = READ_ONCE(gc->shrinker_hits);
diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h
index 2fa6f2e09d07..905944dafbe5 100644
--- a/fs/xfs/xfs_icache.h
+++ b/fs/xfs/xfs_icache.h
@@ -79,7 +79,6 @@ void xfs_inodegc_push(struct xfs_mount *mp);
int xfs_inodegc_flush(struct xfs_mount *mp);
void xfs_inodegc_stop(struct xfs_mount *mp);
void xfs_inodegc_start(struct xfs_mount *mp);
-void xfs_inodegc_cpu_dead(struct xfs_mount *mp, unsigned int cpu);
int xfs_inodegc_register_shrinker(struct xfs_mount *mp);
#endif
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index a25eece3be2b..f4a8879ba0e9 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -60,6 +60,7 @@ struct xfs_error_cfg {
* Per-cpu deferred inode inactivation GC lists.
*/
struct xfs_inodegc {
+ struct xfs_mount *mp;
struct llist_head list;
struct delayed_work work;
int error;
@@ -67,9 +68,7 @@ struct xfs_inodegc {
/* approximate count of inodes in the list */
unsigned int items;
unsigned int shrinker_hits;
-#if defined(DEBUG) || defined(XFS_WARN)
unsigned int cpu;
-#endif
};
/*
@@ -249,6 +248,9 @@ typedef struct xfs_mount {
unsigned int *m_errortag;
struct xfs_kobj m_errortag_kobj;
#endif
+
+ /* cpus that have inodes queued for inactivation */
+ struct cpumask m_inodegc_cpumask;
} xfs_mount_t;
#define M_IGEO(mp) (&(mp)->m_ino_geo)
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index ed29a5022e36..3a91ba3a4c62 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1135,9 +1135,8 @@ xfs_inodegc_init_percpu(
for_each_possible_cpu(cpu) {
gc = per_cpu_ptr(mp->m_inodegc, cpu);
-#if defined(DEBUG) || defined(XFS_WARN)
gc->cpu = cpu;
-#endif
+ gc->mp = mp;
init_llist_head(&gc->list);
gc->items = 0;
gc->error = 0;
@@ -2336,7 +2335,6 @@ xfs_cpu_dead(
spin_lock(&xfs_mount_list_lock);
list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
spin_unlock(&xfs_mount_list_lock);
- xfs_inodegc_cpu_dead(mp, cpu);
spin_lock(&xfs_mount_list_lock);
}
spin_unlock(&xfs_mount_list_lock);
From f5bfa695f02e02415e4bfb36bd83a8bc933a6d4f Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <djwong@kernel.org>
Date: Mon, 11 Sep 2023 08:39:04 -0700
Subject: [PATCH 3/4] xfs: remove the all-mounts list
Revert commit 0ed17f01c8540 ("xfs: introduce all-mounts list for cpu
hotplug notifications") because the cpu hotplug hooks are now pointless,
so we don't need this list anymore.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_mount.h | 1 -
fs/xfs/xfs_super.c | 39 ---------------------------------------
2 files changed, 40 deletions(-)
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index f4a8879ba0e9..6e2806654e94 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -97,7 +97,6 @@ typedef struct xfs_mount {
xfs_buftarg_t *m_ddev_targp; /* saves taking the address */
xfs_buftarg_t *m_logdev_targp;/* ptr to log device */
xfs_buftarg_t *m_rtdev_targp; /* ptr to rt device */
- struct list_head m_mount_list; /* global mount list */
void __percpu *m_inodegc; /* percpu inodegc structures */
/*
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 3a91ba3a4c62..5cced7713cd2 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -56,28 +56,6 @@ static struct kset *xfs_kset; /* top-level xfs sysfs dir */
static struct xfs_kobj xfs_dbg_kobj; /* global debug sysfs attrs */
#endif
-#ifdef CONFIG_HOTPLUG_CPU
-static LIST_HEAD(xfs_mount_list);
-static DEFINE_SPINLOCK(xfs_mount_list_lock);
-
-static inline void xfs_mount_list_add(struct xfs_mount *mp)
-{
- spin_lock(&xfs_mount_list_lock);
- list_add(&mp->m_mount_list, &xfs_mount_list);
- spin_unlock(&xfs_mount_list_lock);
-}
-
-static inline void xfs_mount_list_del(struct xfs_mount *mp)
-{
- spin_lock(&xfs_mount_list_lock);
- list_del(&mp->m_mount_list);
- spin_unlock(&xfs_mount_list_lock);
-}
-#else /* !CONFIG_HOTPLUG_CPU */
-static inline void xfs_mount_list_add(struct xfs_mount *mp) {}
-static inline void xfs_mount_list_del(struct xfs_mount *mp) {}
-#endif
-
enum xfs_dax_mode {
XFS_DAX_INODE = 0,
XFS_DAX_ALWAYS = 1,
@@ -1167,7 +1145,6 @@ xfs_fs_put_super(
xfs_freesb(mp);
xchk_mount_stats_free(mp);
free_percpu(mp->m_stats.xs_stats);
- xfs_mount_list_del(mp);
xfs_inodegc_free_percpu(mp);
xfs_destroy_percpu_counters(mp);
xfs_destroy_mount_workqueues(mp);
@@ -1576,13 +1553,6 @@ xfs_fs_fill_super(
if (error)
goto out_destroy_counters;
- /*
- * All percpu data structures requiring cleanup when a cpu goes offline
- * must be allocated before adding this @mp to the cpu-dead handler's
- * mount list.
- */
- xfs_mount_list_add(mp);
-
/* Allocate stats memory before we do operations that might use it */
mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
if (!mp->m_stats.xs_stats) {
@@ -1780,7 +1750,6 @@ xfs_fs_fill_super(
out_free_stats:
free_percpu(mp->m_stats.xs_stats);
out_destroy_inodegc:
- xfs_mount_list_del(mp);
xfs_inodegc_free_percpu(mp);
out_destroy_counters:
xfs_destroy_percpu_counters(mp);
@@ -2330,14 +2299,6 @@ static int
xfs_cpu_dead(
unsigned int cpu)
{
- struct xfs_mount *mp, *n;
-
- spin_lock(&xfs_mount_list_lock);
- list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
- spin_unlock(&xfs_mount_list_lock);
- spin_lock(&xfs_mount_list_lock);
- }
- spin_unlock(&xfs_mount_list_lock);
return 0;
}
From ef7d9593390a050c50eba5fc02d2cb65a1104434 Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <djwong@kernel.org>
Date: Mon, 11 Sep 2023 08:39:04 -0700
Subject: [PATCH 4/4] xfs: remove CPU hotplug infrastructure
There are no users of the cpu hotplug hooks in xfs now, so remove it.
This reverts f1653c2e2831e ("xfs: introduce CPU hotplug
infrastructure").
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_super.c | 42 +-------------------------------------
include/linux/cpuhotplug.h | 1 -
2 files changed, 1 insertion(+), 42 deletions(-)
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 5cced7713cd2..c8a2dae1dd65 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -2294,39 +2294,6 @@ xfs_destroy_workqueues(void)
destroy_workqueue(xfs_alloc_wq);
}
-#ifdef CONFIG_HOTPLUG_CPU
-static int
-xfs_cpu_dead(
- unsigned int cpu)
-{
- return 0;
-}
-
-static int __init
-xfs_cpu_hotplug_init(void)
-{
- int error;
-
- error = cpuhp_setup_state_nocalls(CPUHP_XFS_DEAD, "xfs:dead", NULL,
- xfs_cpu_dead);
- if (error < 0)
- xfs_alert(NULL,
-"Failed to initialise CPU hotplug, error %d. XFS is non-functional.",
- error);
- return error;
-}
-
-static void
-xfs_cpu_hotplug_destroy(void)
-{
- cpuhp_remove_state_nocalls(CPUHP_XFS_DEAD);
-}
-
-#else /* !CONFIG_HOTPLUG_CPU */
-static inline int xfs_cpu_hotplug_init(void) { return 0; }
-static inline void xfs_cpu_hotplug_destroy(void) {}
-#endif
-
STATIC int __init
init_xfs_fs(void)
{
@@ -2343,13 +2310,9 @@ init_xfs_fs(void)
xfs_dir_startup();
- error = xfs_cpu_hotplug_init();
- if (error)
- goto out;
-
error = xfs_init_caches();
if (error)
- goto out_destroy_hp;
+ goto out;
error = xfs_init_workqueues();
if (error)
@@ -2433,8 +2396,6 @@ init_xfs_fs(void)
xfs_destroy_workqueues();
out_destroy_caches:
xfs_destroy_caches();
- out_destroy_hp:
- xfs_cpu_hotplug_destroy();
out:
return error;
}
@@ -2458,7 +2419,6 @@ exit_xfs_fs(void)
xfs_destroy_workqueues();
xfs_destroy_caches();
xfs_uuid_table_free();
- xfs_cpu_hotplug_destroy();
}
module_init(init_xfs_fs);
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 06dda85f0424..068f7738be22 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -90,7 +90,6 @@ enum cpuhp_state {
CPUHP_FS_BUFF_DEAD,
CPUHP_PRINTK_DEAD,
CPUHP_MM_MEMCQ_DEAD,
- CPUHP_XFS_DEAD,
CPUHP_PERCPU_CNT_DEAD,
CPUHP_RADIX_DEAD,
CPUHP_PAGE_ALLOC,