aboutsummaryrefslogtreecommitdiffstats
path: root/block
diff options
context:
space:
mode:
authorShaohua Li <shaohua.li@intel.com>2010-05-25 10:16:53 +0200
committerJens Axboe <jens.axboe@oracle.com>2010-05-25 10:17:26 +0200
commitd02a2c077fb81f3224c770be62a318165b23b486 (patch)
tree74696554d35fe81d52236d4059ef2af51d870d84 /block
parentb9598db3401282bb27b4aef77e3eee12015f7f29 (diff)
downloadmrst-s0i3-test-d02a2c077fb81f3224c770be62a318165b23b486.tar.gz
mrst-s0i3-test-d02a2c077fb81f3224c770be62a318165b23b486.tar.xz
mrst-s0i3-test-d02a2c077fb81f3224c770be62a318165b23b486.zip
cfq-iosched: fix an oops caused by slab leak
I got below oops when unloading cfq-iosched. Considering scenario: queue A merge to B, C merge to D and B will be merged to D. Before B is merged to D, we do split B. We should put B's reference for D. [ 807.768536] ============================================================================= [ 807.768539] BUG cfq_queue: Objects remaining on kmem_cache_close() [ 807.768541] ----------------------------------------------------------------------------- [ 807.768543] [ 807.768546] INFO: Slab 0xffffea0003e6b4e0 objects=26 used=1 fp=0xffff88011d584fd8 flags=0x200000000004082 [ 807.768550] Pid: 5946, comm: rmmod Tainted: G W 2.6.34-07097-gf4b87de-dirty #724 [ 807.768552] Call Trace: [ 807.768560] [<ffffffff81104e8d>] slab_err+0x8f/0x9d [ 807.768564] [<ffffffff811059e1>] ? flush_cpu_slab+0x0/0x93 [ 807.768569] [<ffffffff8164be52>] ? add_preempt_count+0xe/0xca [ 807.768572] [<ffffffff8164bd9c>] ? sub_preempt_count+0xe/0xb6 [ 807.768577] [<ffffffff81648871>] ? _raw_spin_unlock+0x15/0x30 [ 807.768580] [<ffffffff8164bd9c>] ? sub_preempt_count+0xe/0xb6 [ 807.768584] [<ffffffff811061bc>] list_slab_objects+0x9b/0x19f [ 807.768588] [<ffffffff8164bf0a>] ? add_preempt_count+0xc6/0xca [ 807.768591] [<ffffffff81109e27>] kmem_cache_destroy+0x13f/0x21d [ 807.768597] [<ffffffffa000ff13>] cfq_slab_kill+0x1a/0x43 [cfq_iosched] [ 807.768601] [<ffffffffa000ffcf>] cfq_exit+0x93/0x9e [cfq_iosched] [ 807.768606] [<ffffffff810973a2>] sys_delete_module+0x1b1/0x219 [ 807.768612] [<ffffffff8102fb5b>] system_call_fastpath+0x16/0x1b [ 807.768618] INFO: Object 0xffff88011d584618 @offset=1560 [ 807.768622] INFO: Allocated in cfq_get_queue+0x11e/0x274 [cfq_iosched] age=7173 cpu=1 pid=5496 [ 807.768626] ============================================================================= Cc: stable@kernel.org Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block')
-rw-r--r--block/cfq-iosched.c20
1 files changed, 14 insertions, 6 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index c72e5acc573..5ff4f4850e7 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -2560,15 +2560,10 @@ static void cfq_free_io_context(struct io_context *ioc)
__call_for_each_cic(ioc, cic_free_func);
}
-static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+static void cfq_put_cooperator(struct cfq_queue *cfqq)
{
struct cfq_queue *__cfqq, *next;
- if (unlikely(cfqq == cfqd->active_queue)) {
- __cfq_slice_expired(cfqd, cfqq, 0);
- cfq_schedule_dispatch(cfqd);
- }
-
/*
* If this queue was scheduled to merge with another queue, be
* sure to drop the reference taken on that queue (and others in
@@ -2584,6 +2579,16 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
cfq_put_queue(__cfqq);
__cfqq = next;
}
+}
+
+static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+ if (unlikely(cfqq == cfqd->active_queue)) {
+ __cfq_slice_expired(cfqd, cfqq, 0);
+ cfq_schedule_dispatch(cfqd);
+ }
+
+ cfq_put_cooperator(cfqq);
cfq_put_queue(cfqq);
}
@@ -3536,6 +3541,9 @@ split_cfqq(struct cfq_io_context *cic, struct cfq_queue *cfqq)
}
cic_set_cfqq(cic, NULL, 1);
+
+ cfq_put_cooperator(cfqq);
+
cfq_put_queue(cfqq);
return NULL;
}