From nobody Fri Dec 19 20:07:42 2025 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 5A0D5247DE1 for ; Wed, 12 Mar 2025 16:47:57 +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=1741798078; cv=none; b=uzTwTWFGUmUqbEU3oYgr3B3gHv914G6kmmVRrjZ4c1neti8PY05NA/fVJKUf0P8l6ONKRd/5OOZANNQPtHSxDK/trrNqymdUaBQBtxXbS4F6vo3Byma9LJUoaS0W07sQCxJR8l58ag0/i6tmn2+AXxKuPnQ1VdiynXZu7z3jH8A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741798078; c=relaxed/simple; bh=H37g5zw8JYgcEHcrKgCoScNGY44vZwcAGnWDri47ll4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=FVTU9SzSBeijgGnNj8ovHCOZ+CfUqzwcg7j/9FSeU2fO/z8WJ5QyR0pXB2eVy5PkUK32/f8IGfyeyiADL3B8tJdpz2jenVHQNid+LhUI73rfFruaRVYB2AzfpJ/2vZnEy40JHvI/UwUirq2nGlNu+JRhTBQAqStzuIAzjJDKHlY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=R/vD7NQy; 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="R/vD7NQy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6438C4CEEB; Wed, 12 Mar 2025 16:47:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741798077; bh=H37g5zw8JYgcEHcrKgCoScNGY44vZwcAGnWDri47ll4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R/vD7NQyc6drg6smFF+csAqealwJ9oeCp8RBZuR7gdkEm6tK8IQ8s+pJIAND/ar6p PquW8UddAL7JN0XDsZH2HFLFMoWo5r/oN9cBCPfkqxvHvnJ/p0wIDGaGdOJe07CTx1 orgRMFPr3iwNZd5q7gV5/8pbAVbEctxUSp9NL5rEYQ2t+vvW+7l2FiISNCaI93IeMs rkiorPIVaI6S3a4TTdptzn+1628Vb6MN3dcPlLLZs06TYjWBWAA0BinMGzNouXH9+o /b3FAzYkUDGMgRdI9BPGPkhIacekGiex1o5ZMjQ/Usfed89xuQkdZf/84b7KCgqQlR d2+OCfyvW+pnQ== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , "Liam R. Howlett" , David Hildenbrand , Lorenzo Stoakes , Shakeel Butt , Vlastimil Babka , kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 2/4] mm/madvise: split out populate behavior check logic Date: Wed, 12 Mar 2025 09:47:48 -0700 Message-Id: <20250312164750.59215-3-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250312164750.59215-1-sj@kernel.org> References: <20250312164750.59215-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" madvise_do_behavior() has a long open-coded 'behavior' check for MADV_POPULATE_{READ,WRITE}. It adds multiple layers[1] and make the code arguably take longer time to read. Like is_memory_failure(), split out the check to a separate function. This is not technically removing the additional layer but discourage further extending the switch-case. Also it makes madvise_do_behavior() code shorter and therefore easier to read. [1] https://lore.kernel.org/bd6d0bf1-c79e-46bd-a810-9791efb9ad73@lucifer.lo= cal Signed-off-by: SeongJae Park Reviewed-by: Lorenzo Stoakes Reviewed-by: Shakeel Butt --- mm/madvise.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index c3ab1f283b18..611db868ae38 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1640,6 +1640,17 @@ static bool is_valid_madvise(unsigned long start, si= ze_t len_in, int behavior) return true; } =20 +static bool is_madvise_populate(int behavior) +{ + switch (behavior) { + case MADV_POPULATE_READ: + case MADV_POPULATE_WRITE: + return true; + default: + return false; + } +} + static int madvise_do_behavior(struct mm_struct *mm, unsigned long start, size_t len_in, size_t len, int behavior) { @@ -1653,16 +1664,11 @@ static int madvise_do_behavior(struct mm_struct *mm, end =3D start + len; =20 blk_start_plug(&plug); - switch (behavior) { - case MADV_POPULATE_READ: - case MADV_POPULATE_WRITE: + if (is_madvise_populate(behavior)) error =3D madvise_populate(mm, start, end, behavior); - break; - default: + else error =3D madvise_walk_vmas(mm, start, end, behavior, madvise_vma_behavior); - break; - } blk_finish_plug(&plug); return error; } --=20 2.39.5