From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-172.mta0.migadu.com (out-172.mta0.migadu.com [91.218.175.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 03B052E7391 for ; Tue, 9 Jun 2026 06:15:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780985732; cv=none; b=EI06hRn7lT1ElaQxGXxzwS7WY9Pfw+Qdrqi4xoDDNu4iV2AfdMXgn5iqRZi+Cce8WrbeUQ1/YBYrrKADrtzjkcKbt0zti5aH2PnFZYEcoa2Fhf2TTAypxWeI/nYzkZrYYgv0I82SDi2MmjKUZGiyuqCqsNe7lwQjGaORlfWKoUA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780985732; c=relaxed/simple; bh=UFvl/VyOpDYMjhlydzxQ4k85SuVK3AWcIYyCr3Pr49A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bt7u3u/WotGDDX7Ccp44w8qApuKfbvzrwrSIizvT76jTbxXTKcogSjuK5KtWGoMR5iY3caz1g1akHcu7KmqEtkWm21bYWaY2Q+Sn4LnoxEMltQ/hWjW7oHUMNJEW9wU5/8qa6r0+N9Ta09QPyw3tZZXZI58uVeNPNs6k7nuzgTA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Z8zV2BjC; arc=none smtp.client-ip=91.218.175.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Z8zV2BjC" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1780985728; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OIHUqXQmUUYiluUxjJGbqlbmrFVz6UQUb/30/LyGMbo=; b=Z8zV2BjCyIIWmJUOuq+lpPC144tcwa3dYQzA0MbEaPU04Q8HQiL3ytDgkjwXu7qSG5Vt1G 8EHmclu6rvc8oemzxv47fNi8tHF1o9R4NOTCl0imYYdSuEjWYjWaCaZ0rzlyzknIGPhr36 Z9cyhUeg/Vahz+UVQh1W/YpfPZkITdc= From: Kaitao Cheng To: Andy Shevchenko , Muchun Song , Philipp Reisner , Lars Ellenberg , =?UTF-8?q?Christoph=20B=C3=B6hmwalder?= , Jens Axboe , Takashi Sakamoto , Andrzej Hajda , Neil Armstrong , Robert Foss , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Christian Koenig , Huang Rui , Eddie James , Mark Brown , Maxime Coquelin , Alexandre Torgue , Laxman Dewangan , Thierry Reding , Jonathan Hunter , Sowjanya Komatineni , Davidlohr Bueso , "Paul E . McKenney" , Josh Triplett , Peter Zijlstra , Ingo Molnar , Will Deacon , Boqun Feng , Liam Girdwood , Jaroslav Kysela , Takashi Iwai Cc: Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Matthew Auld , Matthew Brost , Waiman Long , drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, linux1394-devel@lists.sourceforge.net, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-spi@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org, linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , Randy Dunlap , Christian Brauner , David Howells , Luca Ceresoli , Kaitao Cheng , Kaitao Cheng Subject: [PATCH v2 01/14] drbd: Open-code transfer log list walk Date: Tue, 9 Jun 2026 14:13:34 +0800 Message-ID: <20260609061347.93688-2-kaitao.cheng@linux.dev> In-Reply-To: <20260609061347.93688-1-kaitao.cheng@linux.dev> References: <20260609061347.93688-1-kaitao.cheng@linux.dev> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Kaitao Cheng A later change will make list_for_each_entry() cache the next element before entering the loop body. That is the desired behaviour for the common case, but this transfer log walk temporarily drops resource->req_lock and revalidates the cursor before continuing. Keep the loop open-coded so the next request is derived after the body has completed and after the cursor has been adjusted. This preserves the existing traversal semantics and prepares the code for the list iterator update. Signed-off-by: Kaitao Cheng --- drivers/block/drbd/drbd_debugfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/block/drbd/drbd_debugfs.c b/drivers/block/drbd/drbd_debugfs.c index 12460b584bcb..e90cead90e9d 100644 --- a/drivers/block/drbd/drbd_debugfs.c +++ b/drivers/block/drbd/drbd_debugfs.c @@ -308,7 +308,9 @@ static void seq_print_resource_transfer_log_summary(struct seq_file *m, seq_puts(m, "n\tdevice\tvnr\t" RQ_HDR); spin_lock_irq(&resource->req_lock); - list_for_each_entry(req, &connection->transfer_log, tl_requests) { + for (req = list_first_entry(&connection->transfer_log, typeof(*req), tl_requests); + !list_entry_is_head(req, &connection->transfer_log, tl_requests); + req = list_next_entry(req, tl_requests)) { unsigned int tmp = 0; unsigned int s; ++count; -- 2.43.0