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IB/hfi1: Remove critical section gap in sc_buffer_alloc()

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In sc_buffer_alloc(), the sc->alloc_lock is released
before calling sc_release_update(), and it is reacquired
after the function call. This causes CPU lock trading.
Fix it by not dropping the lock before calling
sc_release_update().

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Sebastian Sanchez 2016-12-07 19:33:33 -08:00 committed by Doug Ledford
parent b777f154a0
commit 9b86071c5e
1 changed files with 0 additions and 2 deletions
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2
drivers/infiniband/hw/hfi1/pio.c
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@ -1419,9 +1419,7 @@ retry:
(sc->fill - sc->alloc_free); (sc->fill - sc->alloc_free);
if (blocks > avail) { if (blocks > avail) {
/* still no room, actively update */ /* still no room, actively update */
spin_unlock_irqrestore(&sc->alloc_lock, flags);
sc_release_update(sc); sc_release_update(sc);
spin_lock_irqsave(&sc->alloc_lock, flags);
sc->alloc_free = ACCESS_ONCE(sc->free); sc->alloc_free = ACCESS_ONCE(sc->free);
trycount++; trycount++;
goto retry; goto retry;