From 54f9a64a36e4fc041721a954e674797c2686ea4e Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Thu, 27 Aug 2015 15:58:27 +1000 Subject: [PATCH] powerpc/eeh: atomic_dec_if_positive() to update passthru count No need to have two atomic opertions (update and fetch/check) when decreasing PE's number of passed devices as one atomic operation is enough. Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/eeh.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 00ba5de12256..893978c980da 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -1412,8 +1412,7 @@ void eeh_dev_release(struct pci_dev *pdev) goto out; /* Decrease PE's pass through count */ - atomic_dec(&edev->pe->pass_dev_cnt); - WARN_ON(atomic_read(&edev->pe->pass_dev_cnt) < 0); + WARN_ON(atomic_dec_if_positive(&edev->pe->pass_dev_cnt) < 0); eeh_pe_change_owner(edev->pe); out: mutex_unlock(&eeh_dev_mutex); -- 2.39.5