From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793280852; b=uX4bsiOak/qJRyR3YaZOheZg54hdlNRIglXG30oQ9jLZZK3pJi9aFoSwn7VyGIuB7blQ HpYeWUF7Hqii20tT71SgS/dtQ6uyuk9XHlnc3Ftjkcrr3FS3fNdofSDVdLRAkvPkoBia3 VuPIepPSSWRyz7mlPfPTXqkY6REbaV0eEdSRMzfSdV8eAAoqSLZ1TmHuQ1+qT4Pe4TZoA 8xPOC31RKLdFVEYPiEp0nDtB9vXTJj6R/XMX1hEFJpc7GyFzd4TBLD3gZtvYcuxUkR52I wysKKks9d5Wlb67a9NpEM3PfT7I53aMjVOKhm/m4gynRPGlZ9f47JPENBtHHp9h4TcA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793280852; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=BrjbhUE3Lk64mbF9WVBlM+QXCFFQl9Ca0BDrP9qctY0=; b=UMMUdgzCenggdtog63OE4fi5nXFvrbrk0VuejLOFF8cqNvRMPC73flTslpQbtA8wopqr w3epm009Q2aBFNMgrrkl9jutBmXy/z5HxbbBZ9/kxbW/ocRDHGpDlhIN3sa3oSLS7iCqA FVPoxBsHSt4NgxuiWL64hJ3F6YT4PDwTpJ9IxC2DFneTDouxWrljk57F++3CkxDLiyfYc BsWFaRiFy/LxomTrlbEIQUinqqkkUG592DUMqZHW/80DhvFNZXn3On2I9/RJl/e0zxOaD 4nMj0FnQhdvcysnRBS8WVrpvH6U21t2k1CUvt3rKQx+31PHhHMCQvuSjKeP6JkvSw/w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=nntSbmzL; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BBFC6606A31C for ; Thu, 29 Oct 2026 13:34:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=nntSbmzL Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2D8021F01825; Thu, 29 Oct 2026 13:34:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793280851; bh=BrjbhUE3Lk64mbF9WVBlM+QXCFFQl9Ca0BDrP9qctY0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=nntSbmzLjiTSiUtljPRP6tx2iub7unPBxkVmlPUj/BxlD0zhzJ0oKd88E9P10b0so 18Z29hGP7FuKexQ7dsm9o+LT+PJ6iSnECMzYCA1iW8HadVu7t/JHg/J/AYM322p9KH pj+FqSoJh+1vyk4aFJRgUJxyNSemzH2jJ/9LVK05C4ruaH0RByN6f50DVKyxkSP5Gi 59u03mF1RRY9vZ5HanlgB7vkrfnUcCsUdY9V4b4+q5JcZResApWBV42uxtcgWd1aEb 9VhascsPpHZrvCahWxDKxB8UaisNZo27E/aO9S3qUAZT3cpiP5KlmhvfOQNkCe7aqz by2APqhN6ljWQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RFC 4/9] ext4: don't read the inode block in ext4_sync_inode_metadata() Reply-To: sashiko-reviews@lists.linux.dev To: "Christian Brauner" Cc: linux-ext4@vger.kernel.org, tytso@mit.edu In-Reply-To: <20261029-work-inode-metadata_writeback-v1-4-7d6c678a585d@kernel.org> References: <20261029-work-inode-metadata_writeback-v1-0-7d6c678a585d@kernel.org> <20261029-work-inode-metadata_writeback-v1-4-7d6c678a585d@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 29 Oct 2026 13:34:10 +0000 X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > In nojournal mode ext4_sync_inode_metadata() looks up the inode table > block with __ext4_get_inode_loc_noinmem() which reads it from disk, with > readahead of the inode table on top, if it isn't cached. But a block > that isn't in the buffer cache is neither dirty nor under writeback. So > there's nothing to write or to wait for and reading it in is pointless. >=20 > It's also not something we can afford once inode eviction calls > ->sync_inode_metadata() from reclaim. So look the block up with > sb_find_get_block_nonatomic() instead. >=20 > Note that ext4_get_inode_loc_noio() isn't usable here. It uses the > atomic lookup and that one gives up on a folio that is being migrated. > That's fine for a best-effort fast commit snapshot but not for a data > integrity sync. >=20 > Cc: stable@vger.kernel.org # v7.3 > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261029-work-inode= -metadata_writeback-v1-0-7d6c678a585d@kernel.org?part=3D4