From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 F1EAA32E73E; Tue, 21 Oct 2025 11:44:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761047050; cv=none; b=YXQ4WDSGi0n9N+xkMyll1v9sjsx38q5jrTPeVEQaax1zZt8texUksOFMES3BKoKiLClGA9hEpBHm4wZcAXnR6VXd+/9h8w47cZC5ui73EMYcoNK8UwrVb1/0PprUoHNBi4vOHn4y+vkHbXMoMhO3ZgMQ81oSoHe9y2WuQMco9c0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761047050; c=relaxed/simple; bh=LCe8V3QgmxQPWsHxmkO/HYNSTPj5l9bqGO1onywb9Xk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ct2vH6AjtTg9wSmarZZSQjrABAcmD4G66mh7Wk/JQcYJI/Pub0VjZi+XLsH4jG2iAs4q7UWmqjcyF9UJrHW+ffQIHvJZUSr+7q3W7iK2Q79oD0jlESJn0Z1YAuUNK2UFWKK2tDhEm6fJoLUzUZzH2Wg4GiP4Y4htB56+TRIG6SI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pu1xDtJn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pu1xDtJn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6104C4CEF1; Tue, 21 Oct 2025 11:44:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761047049; bh=LCe8V3QgmxQPWsHxmkO/HYNSTPj5l9bqGO1onywb9Xk=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=pu1xDtJnprXIvW9VopwRTIAuFxGl24Tp6PZAaZBFgrQX/pZ3bXAl2hOhKnTPcKtk+ KZGgSPy3JeSpUQWGgj3S9grTqMDv2O6sUdkQeayHK06RzMjWRu/lFnQeZcE+aZE+tM 48lDjuD+0UDdqnaP6BSeJg+g1Mo15KkOQhZYyDij6esAO8yTEuLtRt7F4mdzjsXJ72 kXngMJev2z7TdiCNLHiMvHRTXjTxUN2tLLyoo9YfC305O9H2VLz6ej8hish4FJUOxK eH7jBdf5SK8mmX9K+nC05D2vRlJlKx0GSLAQyM80ibHAu4HTum3PBK6F19mKOdYjsC Zg31pBPEb1x1Q== From: Christian Brauner Date: Tue, 21 Oct 2025 13:43:10 +0200 Subject: [PATCH RFC DRAFT 04/50] pidfs: raise DCACHE_DONTCACHE explicitly Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20251021-work-namespace-nstree-listns-v1-4-ad44261a8a5b@kernel.org> References: <20251021-work-namespace-nstree-listns-v1-0-ad44261a8a5b@kernel.org> In-Reply-To: <20251021-work-namespace-nstree-listns-v1-0-ad44261a8a5b@kernel.org> To: linux-fsdevel@vger.kernel.org, Josef Bacik , Jeff Layton Cc: Jann Horn , Mike Yuan , =?utf-8?q?Zbigniew_J=C4=99drzejewski-Szmek?= , Lennart Poettering , Daan De Meyer , Aleksa Sarai , Amir Goldstein , Tejun Heo , Johannes Weiner , Thomas Gleixner , Alexander Viro , Jan Kara , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, bpf@vger.kernel.org, Eric Dumazet , Jakub Kicinski , netdev@vger.kernel.org, Arnd Bergmann , Christian Brauner X-Mailer: b4 0.15-dev-96507 X-Developer-Signature: v=1; a=openpgp-sha256; l=824; i=brauner@kernel.org; h=from:subject:message-id; bh=LCe8V3QgmxQPWsHxmkO/HYNSTPj5l9bqGO1onywb9Xk=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWR8L3xzpUw74sT9VzwZYXxT9R+KPFHO3D9ZJZLnoPoXO f5tW1KXdZSyMIhxMciKKbI4tJuEyy3nqdhslKkBM4eVCWQIAxenAExk1mWGP7x7zG8x/LdL3bji doLlwp37ubctLuY+2vb9ieajYpamjTkMf8WUVhmoXBNrrn+06P82MTebamHOX/NtbZOu1/ft2mz 2iQkA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 While pidfs dentries are never hashed and thus retain_dentry() will never consider them for placing them on the LRU it isn't great to always have to go and remember that. Raise DCACHE_DONTCACHE explicitly as a visual marker that dentries aren't kept but freed immediately instead. Signed-off-by: Christian Brauner --- fs/pidfs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/pidfs.c b/fs/pidfs.c index 0ef5b47d796a..db236427fc2c 100644 --- a/fs/pidfs.c +++ b/fs/pidfs.c @@ -1022,6 +1022,7 @@ static int pidfs_init_fs_context(struct fs_context *fc) fc->s_iflags |= SB_I_NOEXEC; fc->s_iflags |= SB_I_NODEV; + ctx->s_d_flags |= DCACHE_DONTCACHE; ctx->ops = &pidfs_sops; ctx->eops = &pidfs_export_operations; ctx->dops = &pidfs_dentry_operations; -- 2.47.3