diff options
| author | Shaohua Li <shaohua.li@intel.com> | 2011-06-27 09:03:47 +0200 |
|---|---|---|
| committer | Andi Kleen <ak@linux.intel.com> | 2011-08-01 13:54:58 -0700 |
| commit | 3cc36915ad70bb028e8b4f748ed4a4e99834e3c0 (patch) | |
| tree | 199ad3b2bd95adbb838408beab4bcc8090f65dd9 /block | |
| parent | cf4ca69d46d49eb6fd8803f6618dd60184892835 (diff) | |
cfq-iosched: fix a rcu warning
commit 3181faa85bda3dc3f5e630a1846526c9caaa38e3 upstream.
I got a rcu warnning at boot. the ioc->ioc_data is rcu_deferenced, but
doesn't hold rcu_read_lock.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/cfq-iosched.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 46b88948725b..803ad8be830c 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2615,11 +2615,14 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd, smp_wmb(); cic->key = cfqd_dead_key(cfqd); + rcu_read_lock(); if (rcu_dereference(ioc->ioc_data) == cic) { + rcu_read_unlock(); spin_lock(&ioc->lock); rcu_assign_pointer(ioc->ioc_data, NULL); spin_unlock(&ioc->lock); - } + } else + rcu_read_unlock(); if (cic->cfqq[BLK_RW_ASYNC]) { cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]); |