diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2017-09-21 18:21:40 +0300 |
|---|---|---|
| committer | Alex Williamson <alex.williamson@redhat.com> | 2017-11-06 21:24:35 +0300 |
| commit | 94e2cc4dba39efbb63e84cd4f7243627c16ceac5 (patch) | |
| tree | 175fe887e65dc3029129904b2130ace1b23ebb70 | |
| parent | a593472591a5cf2d91244bc3f319c9dd91119343 (diff) | |
| download | linux-94e2cc4dba39efbb63e84cd4f7243627c16ceac5.tar.xz | |
iommu/iova: Use raw_cpu_ptr() instead of get_cpu_ptr() for ->fq
get_cpu_ptr() disabled preemption and returns the ->fq object of the
current CPU. raw_cpu_ptr() does the same except that it not disable
preemption which means the scheduler can move it to another CPU after it
obtained the per-CPU object.
In this case this is not bad because the data structure itself is
protected with a spin_lock. This change shouldn't matter however on RT
it does because the sleeping lock can't be accessed with disabled
preemption.
Cc: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Reported-by: vinadhy@gmail.com
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| -rw-r--r-- | drivers/iommu/iova.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 84bda3a4dafc..466aaa8ba841 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -542,7 +542,7 @@ void queue_iova(struct iova_domain *iovad, unsigned long pfn, unsigned long pages, unsigned long data) { - struct iova_fq *fq = get_cpu_ptr(iovad->fq); + struct iova_fq *fq = raw_cpu_ptr(iovad->fq); unsigned long flags; unsigned idx; @@ -572,8 +572,6 @@ void queue_iova(struct iova_domain *iovad, if (atomic_cmpxchg(&iovad->fq_timer_on, 0, 1) == 0) mod_timer(&iovad->fq_timer, jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT)); - - put_cpu_ptr(iovad->fq); } EXPORT_SYMBOL_GPL(queue_iova); |