Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753157AbcKGMZK (ORCPT ); Mon, 7 Nov 2016 07:25:10 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:25337 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751296AbcKGMXm (ORCPT ); Mon, 7 Nov 2016 07:23:42 -0500 From: John Garry To: , CC: , , , , John Garry Subject: [PATCH 10/11] hisi_sas: use atomic64_t for hisi_sas_device.running_req Date: Mon, 7 Nov 2016 20:48:39 +0800 Message-ID: <1478522920-108145-11-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1478522920-108145-1-git-send-email-john.garry@huawei.com> References: <1478522920-108145-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.212.75] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3101 Lines: 97 Sometimes the value of hisi_sas_device.running_req would go negative unless we have the check for running_req >= 0 before trying to decrement. This is because using running_req is not thread-safe. As such, the value for running_req may be actually incorrect, so use atomic64_t instead. Signed-off-by: John Garry Reviewed-by: Xiang Chen --- drivers/scsi/hisi_sas/hisi_sas.h | 2 +- drivers/scsi/hisi_sas/hisi_sas_main.c | 9 +++++---- drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 4 ++-- drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 4 ++-- 4 files changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h index bf59fab..8b5ecc6 100644 --- a/drivers/scsi/hisi_sas/hisi_sas.h +++ b/drivers/scsi/hisi_sas/hisi_sas.h @@ -111,7 +111,7 @@ struct hisi_sas_device { struct domain_device *sas_device; u64 attached_phy; u64 device_id; - u64 running_req; + atomic64_t running_req; u8 dev_status; }; diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c index 504cbcf..18e2194 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_main.c +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c @@ -162,8 +162,8 @@ static void hisi_sas_slot_abort(struct work_struct *work) hisi_sas_slot_task_free(hisi_hba, task, abort_slot); if (task->task_done) task->task_done(task); - if (sas_dev && sas_dev->running_req) - sas_dev->running_req--; + if (sas_dev) + atomic64_dec(&sas_dev->running_req); } static int hisi_sas_task_prep(struct sas_task *task, struct hisi_hba *hisi_hba, @@ -303,7 +303,7 @@ static int hisi_sas_task_prep(struct sas_task *task, struct hisi_hba *hisi_hba, hisi_hba->slot_prep = slot; - sas_dev->running_req++; + atomic64_inc(&sas_dev->running_req); ++(*pass); return 0; @@ -1027,7 +1027,8 @@ static int hisi_sas_query_task(struct sas_task *task) hisi_hba->slot_prep = slot; - sas_dev->running_req++; + atomic64_inc(&sas_dev->running_req); + /* send abort command to our chip */ hisi_hba->hw->start_delivery(hisi_hba); diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c index bbc5760..05177fc 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c @@ -1366,8 +1366,8 @@ static int slot_complete_v1_hw(struct hisi_hba *hisi_hba, } out: - if (sas_dev && sas_dev->running_req) - sas_dev->running_req--; + if (sas_dev) + atomic64_dec(&sas_dev->running_req); hisi_sas_slot_task_free(hisi_hba, task, slot); sts = ts->stat; diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c index cda3baf..e88113a 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c @@ -1728,8 +1728,8 @@ static void slot_err_v2_hw(struct hisi_hba *hisi_hba, } out: - if (sas_dev && sas_dev->running_req) - sas_dev->running_req--; + if (sas_dev) + atomic64_dec(&sas_dev->running_req); hisi_sas_slot_task_free(hisi_hba, task, slot); sts = ts->stat; -- 1.9.1