diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2010-04-06 14:51:31 (GMT) |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2015-02-13 22:20:41 (GMT) |
| commit | 7ea336a7833a210873feaa9375dab0836e4064e6 (patch) | |
| tree | 024198b56ddad6fefc779aa25279f9f45d403738 /drivers/md | |
| parent | 9139a5a61f315a2c56bb71df6fbb65df7d5726b5 (diff) | |
| download | linux-fsl-qoriq-7ea336a7833a210873feaa9375dab0836e4064e6.tar.xz | |
md: raid5: Make raid5_percpu handling RT aware
__raid_run_ops() disables preemption with get_cpu() around the access
to the raid5_percpu variables. That causes scheduling while atomic
spews on RT.
Serialize the access to the percpu data with a lock and keep the code
preemptible.
Reported-by: Udo van den Heuvel <udovdh@xs4all.nl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Udo van den Heuvel <udovdh@xs4all.nl>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/raid5.c | 7 | ||||
| -rw-r--r-- | drivers/md/raid5.h | 1 |
2 files changed, 6 insertions, 2 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 7b54c3b..44d6dcf 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -1545,8 +1545,9 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request) struct raid5_percpu *percpu; unsigned long cpu; - cpu = get_cpu(); + cpu = get_cpu_light(); percpu = per_cpu_ptr(conf->percpu, cpu); + spin_lock(&percpu->lock); if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { ops_run_biofill(sh); overlap_clear++; @@ -1598,7 +1599,8 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request) if (test_and_clear_bit(R5_Overlap, &dev->flags)) wake_up(&sh->raid_conf->wait_for_overlap); } - put_cpu(); + spin_unlock(&percpu->lock); + put_cpu_light(); } static int grow_one_stripe(struct r5conf *conf) @@ -5463,6 +5465,7 @@ static int raid5_alloc_percpu(struct r5conf *conf) __func__, cpu); break; } + spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock); } put_online_cpus(); diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 2113ffa..0a5e1e1 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -444,6 +444,7 @@ struct r5conf { int recovery_disabled; /* per cpu variables */ struct raid5_percpu { + spinlock_t lock; /* Protection for -RT */ struct page *spare_page; /* Used when checking P/Q in raid6 */ void *scribble; /* space for constructing buffer * lists and performing address |