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Shenoy" , , , Swapnil Sapkal , "K Prateek Nayak" Subject: [PATCH v2 2/4] kernel/watch_queue: Use pipe_buf() to retrieve the pipe buffer Date: Fri, 7 Mar 2025 05:29:17 +0000 Message-ID: <20250307052919.34542-3-kprateek.nayak@amd.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250307052919.34542-1-kprateek.nayak@amd.com> References: <20250307052919.34542-1-kprateek.nayak@amd.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: SATLEXMB04.amd.com (10.181.40.145) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ1PEPF000023D4:EE_|PH8PR12MB6724:EE_ X-MS-Office365-Filtering-Correlation-Id: c0ac77e8-fc05-41d9-0e82-08dd5d392356 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|82310400026|376014|7416014|36860700013|1800799024; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:SATLEXMB04.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(82310400026)(376014)(7416014)(36860700013)(1800799024);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Mar 2025 05:30:14.2902 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c0ac77e8-fc05-41d9-0e82-08dd5d392356 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF000023D4.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB6724 Use pipe_buf() helper to retrieve the pipe buffer in post_one_notification() replacing the open-coded the logic. Suggested-by: Oleg Nesterov Signed-off-by: K Prateek Nayak --- Changelog: RFC v1..v2: o New patch. --- kernel/watch_queue.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/watch_queue.c b/kernel/watch_queue.c index 5267adeaa403..605129eb61a1 100644 --- a/kernel/watch_queue.c +++ b/kernel/watch_queue.c @@ -101,12 +101,11 @@ static bool post_one_notification(struct watch_queue *wqueue, struct pipe_inode_info *pipe = wqueue->pipe; struct pipe_buffer *buf; struct page *page; - unsigned int head, tail, mask, note, offset, len; + unsigned int head, tail, note, offset, len; bool done = false; spin_lock_irq(&pipe->rd_wait.lock); - mask = pipe->ring_size - 1; head = pipe->head; tail = pipe->tail; if (pipe_full(head, tail, pipe->ring_size)) @@ -124,7 +123,7 @@ static bool post_one_notification(struct watch_queue *wqueue, memcpy(p + offset, n, len); kunmap_atomic(p); - buf = &pipe->bufs[head & mask]; + buf = pipe_buf(pipe, head); buf->page = page; buf->private = (unsigned long)wqueue; buf->ops = &watch_queue_pipe_buf_ops; @@ -147,7 +146,7 @@ static bool post_one_notification(struct watch_queue *wqueue, return done; lost: - buf = &pipe->bufs[(head - 1) & mask]; + buf = pipe_buf(pipe, head - 1); buf->flags |= PIPE_BUF_FLAG_LOSS; goto out; }