RE: [PATCH resend 1/2] be2iscsi: Remove unnecessary synchronize_irq() before free_irq()

[Jitendra Bhivare <jitendra.bhivare@broadcom.com>]

>-----Original Message-----
>From: linux-scsi-owner@vger.kernel.org [mailto:linux-scsi-
>owner@vger.kernel.org] On Behalf Of Lars-Peter Clausen
>Sent: Friday, March 04, 2016 3:45 PM
>To: James E.J. Bottomley; Martin K. Petersen
>Cc: Sathya Prakash; Chaitra P B; Suganath Prabu Subramani; Jitendra
Bhivare;
>linux-scsi@vger.kernel.org; MPT-FusionLinux.pdl@broadcom.com; Lars-Peter
>Clausen
>Subject: [PATCH resend 1/2] be2iscsi: Remove unnecessary
synchronize_irq()
>before free_irq()
>
>Calling synchronize_irq() right before free_irq() is quite useless. On
one hand the
>IRQ can easily fire again before free_irq() is entered, on the other hand
free_irq()
>itself calls synchronize_irq() internally (in a race condition free way),
before any
>state associated with the IRQ is freed.
>
>Patch was generated using the following semantic patch:
>// <smpl>
>@@
>expression irq;
>@@
>-synchronize_irq(irq);
> free_irq(irq, ...);
>// </smpl>
>
>Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
>---
> drivers/scsi/be2iscsi/be_main.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
>diff --git a/drivers/scsi/be2iscsi/be_main.c
b/drivers/scsi/be2iscsi/be_main.c
>index b51e726..e89a0f8d 100644
>--- a/drivers/scsi/be2iscsi/be_main.c
>+++ b/drivers/scsi/be2iscsi/be_main.c
>@@ -5303,15 +5303,12 @@ static void beiscsi_quiesce(struct beiscsi_hba
*phba,
> 	if (phba->msix_enabled) {
> 		for (i = 0; i <= phba->num_cpus; i++) {
> 			msix_vec = phba->msix_entries[i].vector;
>-			synchronize_irq(msix_vec);
> 			free_irq(msix_vec, &phwi_context->be_eq[i]);
> 			kfree(phba->msi_name[i]);
> 		}
> 	} else
>-		if (phba->pcidev->irq) {
>-			synchronize_irq(phba->pcidev->irq);
>+		if (phba->pcidev->irq)
> 			free_irq(phba->pcidev->irq, phba);
>-		}
> 	pci_disable_msix(phba->pcidev);
> 	cancel_delayed_work_sync(&phba->beiscsi_hw_check_task);
>
>--
>2.1.4

Reviewed-by: Jitendra Bhivare <jitendra.bhivare@broadcom.com>

Thanks,

JB