Commit 54f9a64a authored Aug 27, 2015 by Gavin Shan Committed by Michael Ellerman Oct 15, 2015

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 <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent 2e1a2556

arch/powerpc/kernel/eeh.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -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);