From nobody Fri Dec 19 17:42:08 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 D38EB1C5D4E for ; Wed, 5 Mar 2025 18:16:23 +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=1741198583; cv=none; b=k2ht3Nijnof4XNTF2iV5HYuA+I6r5TJlK/0n+toAaJIW10j64u3UfOhBv4IRi2Gx3fgzaiOX2WVxLfx9ZKK/tNUB/Tl66dNZZpX7a6FFmLuklpoWP2sZ+/4GzKseh/a79GVwAUasWYAVkUlo2RZQJSMDkn5hejS0vO38i4fcsLw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741198583; c=relaxed/simple; bh=Hf/IsCKuh49/H9FxeO83Nv8vZIFMcDB1quEptKUrTMY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=UxFtrMUjxPSa+gtMmiXvvEUvGBlTcgFUEmKPG2PEs9RfdCV3FovKyuSuoeLvI6Dxrr6nm4IMz+mVEyqLaZYFAFlrg2QqDmiO+YCs5KR+NlJZdj1zVS9cnmkYiR5hh2w6w6b0leVNAETaBHWs0t7j6dds5AI0416AblZqBr3cBIg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ia7q5BFn; 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="Ia7q5BFn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F099C4CEE2; Wed, 5 Mar 2025 18:16:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741198583; bh=Hf/IsCKuh49/H9FxeO83Nv8vZIFMcDB1quEptKUrTMY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ia7q5BFnvBQEdZiYG/J9924zrl9GGOQcILKyQtO2540WBcXGDi74PQbLvgXupSOUU uRq2YOJyjf13O6CJrtwZp7ybsYd/NWISFt06+mKck3lNr1V6HS+rsBPAtfhYtxAV/m 9mGzaCAZQ1VmtWZETYtdNHp93km18Jza5GUnZc8azzucVpDXHQay5QjAfaQ9Rxa6tQ ZEBt05yTnUAhWgCFjAhWlkb4Al10XBa5hpCLWeZ9fUMHELUlrz/Wn7MbpZTN5XSDOz rqOnzF+7m8gCiV6mCEjnfk01x6pPUjmbHD2tvZReVbxf58LtttlkbasvRkWlCQLwkV 8w93AORgrrNRQ== From: SeongJae Park To: Cc: SeongJae Park , "Liam R. Howlett" , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Shakeel Butt , Vlastimil Babka , kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 03/16] mm/madvise: deduplicate madvise_do_behavior() skip case handlings Date: Wed, 5 Mar 2025 10:15:58 -0800 Message-Id: <20250305181611.54484-4-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250305181611.54484-1-sj@kernel.org> References: <20250305181611.54484-1-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" The logic for checking if a given madvise() request for a single memory range can skip real work, namely madvise_do_behavior(), is duplicated in do_madvise() and vector_madvise(). Split out the logic to a function and resue it. Signed-off-by: SeongJae Park --- mm/madvise.c | 53 +++++++++++++++++++++++++++++----------------------- 1 file changed, 30 insertions(+), 23 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index 4a91590656dc..265b325d8829 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1633,6 +1633,27 @@ static bool is_valid_madvise(unsigned long start, si= ze_t len_in, int behavior) return true; } =20 +/* + * madvise_should_skip() - Return if an madivse request can skip real work= s. + * @start: Start address of madvise-requested address range. + * @len_in: Length of madvise-requested address range. + * @behavior: Requested madvise behavor. + * @err: Pointer to store an error code from the check. + */ +static bool madvise_should_skip(unsigned long start, size_t len_in, + int behavior, int *err) +{ + if (!is_valid_madvise(start, len_in, behavior)) { + *err =3D -EINVAL; + return true; + } + if (start + PAGE_ALIGN(len_in) =3D=3D start) { + *err =3D 0; + return true; + } + return false; +} + static bool is_memory_populate(int behavior) { switch (behavior) { @@ -1740,23 +1761,15 @@ static int madvise_do_behavior(struct mm_struct *mm, */ int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, i= nt behavior) { - unsigned long end; int error; - size_t len; - - if (!is_valid_madvise(start, len_in, behavior)) - return -EINVAL; - - len =3D PAGE_ALIGN(len_in); - end =3D start + len; - - if (end =3D=3D start) - return 0; =20 + if (madvise_should_skip(start, len_in, behavior, &error)) + return error; error =3D madvise_lock(mm, behavior); if (error) return error; - error =3D madvise_do_behavior(mm, start, len_in, len, behavior); + error =3D madvise_do_behavior(mm, start, len_in, PAGE_ALIGN(len_in), + behavior); madvise_unlock(mm, behavior); =20 return error; @@ -1783,19 +1796,13 @@ static ssize_t vector_madvise(struct mm_struct *mm,= struct iov_iter *iter, while (iov_iter_count(iter)) { unsigned long start =3D (unsigned long)iter_iov_addr(iter); size_t len_in =3D iter_iov_len(iter); - size_t len; - - if (!is_valid_madvise(start, len_in, behavior)) { - ret =3D -EINVAL; - break; - } + int error; =20 - len =3D PAGE_ALIGN(len_in); - if (start + len =3D=3D start) - ret =3D 0; + if (madvise_should_skip(start, len_in, behavior, &error)) + ret =3D error; else - ret =3D madvise_do_behavior(mm, start, len_in, len, - behavior); + ret =3D madvise_do_behavior(mm, start, len_in, + PAGE_ALIGN(len_in), behavior); /* * An madvise operation is attempting to restart the syscall, * but we cannot proceed as it would not be correct to repeat --=20 2.39.5