* [PATCH 2/3] batman-adv: prefer kfree_rcu() over call_rcu() with free-only callbacks
2024-04-05 8:45 [PATCH 0/3] pull request for net-next: batman-adv 2024-04-05 Simon Wunderlich
2024-04-05 8:45 ` [PATCH 1/3] batman-adv: Start new development cycle Simon Wunderlich
@ 2024-04-05 8:45 ` Simon Wunderlich
2024-04-05 8:45 ` [PATCH 3/3] batman-adv: bypass empty buckets in batadv_purge_orig_ref() Simon Wunderlich
2 siblings, 0 replies; 4+ messages in thread
From: Simon Wunderlich @ 2024-04-05 8:45 UTC (permalink / raw)
To: kuba, davem
Cc: netdev, b.a.t.m.a.n, Dmitry Antipov, Sven Eckelmann,
Simon Wunderlich
From: Dmitry Antipov <dmantipov@yandex.ru>
Drop 'batadv_tt_local_entry_free_rcu()', 'batadv_tt_global_entry_free_rcu()'
and 'batadv_tt_orig_list_entry_free_rcu()' in favor of 'kfree_rcu()' in
'batadv_tt_local_entry_release()', 'batadv_tt_global_entry_release()' and
'batadv_tt_orig_list_entry_release()', respectively.
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
net/batman-adv/translation-table.c | 47 ++----------------------------
1 file changed, 3 insertions(+), 44 deletions(-)
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index b95c36765d04..0555cb611489 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -208,20 +208,6 @@ batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
return tt_global_entry;
}
-/**
- * batadv_tt_local_entry_free_rcu() - free the tt_local_entry
- * @rcu: rcu pointer of the tt_local_entry
- */
-static void batadv_tt_local_entry_free_rcu(struct rcu_head *rcu)
-{
- struct batadv_tt_local_entry *tt_local_entry;
-
- tt_local_entry = container_of(rcu, struct batadv_tt_local_entry,
- common.rcu);
-
- kmem_cache_free(batadv_tl_cache, tt_local_entry);
-}
-
/**
* batadv_tt_local_entry_release() - release tt_local_entry from lists and queue
* for free after rcu grace period
@@ -236,7 +222,7 @@ static void batadv_tt_local_entry_release(struct kref *ref)
batadv_softif_vlan_put(tt_local_entry->vlan);
- call_rcu(&tt_local_entry->common.rcu, batadv_tt_local_entry_free_rcu);
+ kfree_rcu(tt_local_entry, common.rcu);
}
/**
@@ -254,20 +240,6 @@ batadv_tt_local_entry_put(struct batadv_tt_local_entry *tt_local_entry)
batadv_tt_local_entry_release);
}
-/**
- * batadv_tt_global_entry_free_rcu() - free the tt_global_entry
- * @rcu: rcu pointer of the tt_global_entry
- */
-static void batadv_tt_global_entry_free_rcu(struct rcu_head *rcu)
-{
- struct batadv_tt_global_entry *tt_global_entry;
-
- tt_global_entry = container_of(rcu, struct batadv_tt_global_entry,
- common.rcu);
-
- kmem_cache_free(batadv_tg_cache, tt_global_entry);
-}
-
/**
* batadv_tt_global_entry_release() - release tt_global_entry from lists and
* queue for free after rcu grace period
@@ -282,7 +254,7 @@ void batadv_tt_global_entry_release(struct kref *ref)
batadv_tt_global_del_orig_list(tt_global_entry);
- call_rcu(&tt_global_entry->common.rcu, batadv_tt_global_entry_free_rcu);
+ kfree_rcu(tt_global_entry, common.rcu);
}
/**
@@ -407,19 +379,6 @@ static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node,
batadv_tt_global_size_mod(orig_node, vid, -1);
}
-/**
- * batadv_tt_orig_list_entry_free_rcu() - free the orig_entry
- * @rcu: rcu pointer of the orig_entry
- */
-static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
-{
- struct batadv_tt_orig_list_entry *orig_entry;
-
- orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu);
-
- kmem_cache_free(batadv_tt_orig_cache, orig_entry);
-}
-
/**
* batadv_tt_orig_list_entry_release() - release tt orig entry from lists and
* queue for free after rcu grace period
@@ -433,7 +392,7 @@ static void batadv_tt_orig_list_entry_release(struct kref *ref)
refcount);
batadv_orig_node_put(orig_entry->orig_node);
- call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
+ kfree_rcu(orig_entry, rcu);
}
/**
--
2.39.2
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 3/3] batman-adv: bypass empty buckets in batadv_purge_orig_ref()
2024-04-05 8:45 [PATCH 0/3] pull request for net-next: batman-adv 2024-04-05 Simon Wunderlich
2024-04-05 8:45 ` [PATCH 1/3] batman-adv: Start new development cycle Simon Wunderlich
2024-04-05 8:45 ` [PATCH 2/3] batman-adv: prefer kfree_rcu() over call_rcu() with free-only callbacks Simon Wunderlich
@ 2024-04-05 8:45 ` Simon Wunderlich
2 siblings, 0 replies; 4+ messages in thread
From: Simon Wunderlich @ 2024-04-05 8:45 UTC (permalink / raw)
To: kuba, davem
Cc: netdev, b.a.t.m.a.n, Eric Dumazet, Sven Eckelmann,
Simon Wunderlich
From: Eric Dumazet <edumazet@google.com>
Many syzbot reports are pointing to soft lockups in
batadv_purge_orig_ref() [1]
Root cause is unknown, but we can avoid spending too much
time there and perhaps get more interesting reports.
[1]
watchdog: BUG: soft lockup - CPU#0 stuck for 27s! [kworker/u4:6:621]
Modules linked in:
irq event stamp: 6182794
hardirqs last enabled at (6182793): [<ffff8000801dae10>] __local_bh_enable_ip+0x224/0x44c kernel/softirq.c:386
hardirqs last disabled at (6182794): [<ffff80008ad66a78>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (6182794): [<ffff80008ad66a78>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last enabled at (6182792): [<ffff80008aab71c4>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last enabled at (6182792): [<ffff80008aab71c4>] batadv_purge_orig_ref+0x114c/0x1228 net/batman-adv/originator.c:1287
softirqs last disabled at (6182790): [<ffff80008aab61dc>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (6182790): [<ffff80008aab61dc>] batadv_purge_orig_ref+0x164/0x1228 net/batman-adv/originator.c:1271
CPU: 0 PID: 621 Comm: kworker/u4:6 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: bat_events batadv_purge_orig
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : should_resched arch/arm64/include/asm/preempt.h:79 [inline]
pc : __local_bh_enable_ip+0x228/0x44c kernel/softirq.c:388
lr : __local_bh_enable_ip+0x224/0x44c kernel/softirq.c:386
sp : ffff800099007970
x29: ffff800099007980 x28: 1fffe00018fce1bd x27: dfff800000000000
x26: ffff0000d2620008 x25: ffff0000c7e70de8 x24: 0000000000000001
x23: 1fffe00018e57781 x22: dfff800000000000 x21: ffff80008aab71c4
x20: ffff0001b40136c0 x19: ffff0000c72bbc08 x18: 1fffe0001a817bb0
x17: ffff800125414000 x16: ffff80008032116c x15: 0000000000000001
x14: 1fffe0001ee9d610 x13: 0000000000000000 x12: 0000000000000003
x11: 0000000000000000 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 00000000005e5789 x7 : ffff80008aab61dc x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000006 x1 : 0000000000000080 x0 : ffff800125414000
Call trace:
__daif_local_irq_enable arch/arm64/include/asm/irqflags.h:27 [inline]
arch_local_irq_enable arch/arm64/include/asm/irqflags.h:49 [inline]
__local_bh_enable_ip+0x228/0x44c kernel/softirq.c:386
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_purge_orig_ref+0x114c/0x1228 net/batman-adv/originator.c:1287
batadv_purge_orig+0x20/0x70 net/batman-adv/originator.c:1300
process_one_work+0x694/0x1204 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x938/0xef4 kernel/workqueue.c:2787
kthread+0x288/0x310 kernel/kthread.c:388
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:51
lr : default_idle_call+0xf8/0x128 kernel/sched/idle.c:103
sp : ffff800093a17d30
x29: ffff800093a17d30 x28: dfff800000000000 x27: 1ffff00012742fb4
x26: ffff80008ec9d000 x25: 0000000000000000 x24: 0000000000000002
x23: 1ffff00011d93a74 x22: ffff80008ec9d3a0 x21: 0000000000000000
x20: ffff0000c19dbc00 x19: ffff8000802d0fd8 x18: 1fffe00036804396
x17: ffff80008ec9d000 x16: ffff8000802d089c x15: 0000000000000001
x14: 1fffe00036805f10 x13: 0000000000000000 x12: 0000000000000003
x11: 0000000000000001 x10: 0000000000000003 x9 : 0000000000000000
x8 : 00000000000ce8d1 x7 : ffff8000804609e4 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff80008ad6aac0
x2 : 0000000000000000 x1 : ffff80008aedea60 x0 : ffff800125436000
Call trace:
__daif_local_irq_enable arch/arm64/include/asm/irqflags.h:27 [inline]
arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:49
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1f0/0x4e8 kernel/sched/idle.c:312
cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:410
secondary_start_kernel+0x198/0x1c0 arch/arm64/kernel/smp.c:272
__secondary_switched+0xb8/0xbc arch/arm64/kernel/head.S:404
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
net/batman-adv/originator.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 71c143d4b6d0..ac74f6ead62d 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -1266,6 +1266,8 @@ void batadv_purge_orig_ref(struct batadv_priv *bat_priv)
/* for all origins... */
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
+ if (hlist_empty(head))
+ continue;
list_lock = &hash->list_locks[i];
spin_lock_bh(list_lock);
--
2.39.2
^ permalink raw reply related [flat|nested] 4+ messages in thread