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authorDan Williams <dan.j.williams@intel.com>2009-07-14 13:38:29 -0700
committerDan Williams <dan.j.williams@intel.com>2009-08-29 19:12:39 -0700
commit72be12f0c39df46832403cbfd82e132a883f5ddc (patch)
tree61a4014d28852692464aca3f509d2024e7006f68 /drivers/dma
parent507fbec4cff442ebce6706db34603bfb9cc3b5a9 (diff)
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iop-adma: fix lockdep false positive
lockdep correctly identifies a potential recursive locking case for iop_chan->lock, but in the dependency submission case we expect that the same class will be acquired for both the parent dependency and the child channel. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/iop-adma.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c
index ce45f3fb0343..9c752bd295e1 100644
--- a/drivers/dma/iop-adma.c
+++ b/drivers/dma/iop-adma.c
@@ -288,7 +288,12 @@ static void iop_adma_tasklet(unsigned long data)
{
struct iop_adma_chan *iop_chan = (struct iop_adma_chan *) data;
- spin_lock(&iop_chan->lock);
+ /* lockdep will flag depedency submissions as potentially
+ * recursive locking, this is not the case as a dependency
+ * submission will never recurse a channels submit routine.
+ * There are checks in async_tx.c to prevent this.
+ */
+ spin_lock_nested(&iop_chan->lock, SINGLE_DEPTH_NESTING);
__iop_adma_slot_cleanup(iop_chan);
spin_unlock(&iop_chan->lock);
}