From nobody Mon Nov 25 15:35:30 2024 Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) (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 8C44917C213; Sun, 27 Oct 2024 17:58:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.60.130.6 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730051939; cv=none; b=ae5OOZSenWAGYeofoR/e0vMRprw1I1lqb0MQzQI7ZzlbloLxAm5LwgW9FmHv/boVYc62DQb4zKpB/J6yaeROQz/YHOntkwpqk4kiPmPvxuD3R0ML8uIwTQtz+HhPLy18hstbHF4ffjgLrfCbDBvVyIB8NNme2CYmDfa09+EEqCg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730051939; c=relaxed/simple; bh=ZG1FfEjGllD/phuvR3uOMeVGzSPc7fDfEJoiaGQStYU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=YYUAJVx1cums525qoACqha2zQWj6FkB9nEOO9yniJWt76K3vjugTxqctC4ykau0mSn+5TuxhZ3WS6S+exjsHHF3Nuziwy3e5EXs0dS04/6H1ikx01BdaH3+sOXUpTtYbgKIIHEWQ+9ZwVAy7Uyh2mdWurqhEXQFbEffvYrzBagE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=LWOACRw+; arc=none smtp.client-ip=178.60.130.6 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="LWOACRw+" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=EjvE5ECkO4a4IWIH2md5SXeAC7aZ8rGsxgHC6JRzPsc=; b=LWOACRw+dPktdCnjBVPNnav3wG J412nBd0B+W3uFXYRYz5YMfapM74Y+LsSfRSbsb1J0iKD+9MlPz/bJT71PTbbaN0oIS+57F4drsed IHASrgssG6FW3L2dR1Zle2wbESYJneUhGRsWbjgWvXVa0dIDIH6ueDJ1D0di1VYcDMQ6ssKtk9Xx6 QLZOHz+6NdPIDz57IsedMvnSginavJhCTEa/jJVF6rjGAqMBqIvJuScPDp88UCVwO0CFiQ92mVsE+ D4bs1vZDGXa/91LPiT3Y87ft+OUv6JU1u9Km17P5zrXoGboGG5GIuP8lWss4AZ+ZdeLPGkkWTwjOt +t2o+55g==; Received: from [187.36.213.55] (helo=morissey..) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1t57X9-00Fn6f-UU; Sun, 27 Oct 2024 18:58:36 +0100 From: =?UTF-8?q?Ma=C3=ADra=20Canal?= To: Jonathan Corbet , Andrew Morton , Hugh Dickins , Barry Song , David Hildenbrand , Ryan Roberts , Baolin Wang , Lance Yang Cc: linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-dev@igalia.com, =?UTF-8?q?Ma=C3=ADra=20Canal?= Subject: [PATCH 3/3] mm: shmem: override mTHP shmem default with a kernel parameter Date: Sun, 27 Oct 2024 14:36:39 -0300 Message-ID: <20241027175743.1056710-4-mcanal@igalia.com> X-Mailer: git-send-email 2.46.2 In-Reply-To: <20241027175743.1056710-1-mcanal@igalia.com> References: <20241027175743.1056710-1-mcanal@igalia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Add the ``thp_shmem=3D`` kernel command line to allow specifying the default policy of each supported shmem hugepage size. The kernel parameter accepts the following format: thp_shmem=3D[KMG],[KMG]:;[KMG]-[KMG]: For example, thp_shmem=3D16K-64K:always;128K,512K:inherit;256K:advise;1M-2M:never;4M-8M:= within_size By configuring the default policy of several shmem huge pages, the user can take advantage of mTHP before it's been configured through sysfs. Signed-off-by: Ma=C3=ADra Canal --- .../admin-guide/kernel-parameters.txt | 10 ++ Documentation/admin-guide/mm/transhuge.rst | 17 +++ mm/shmem.c | 109 +++++++++++++++++- 3 files changed, 135 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index acabb04d0dd4..595fa096e28b 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6700,6 +6700,16 @@ Force threading of all interrupt handlers except those marked explicitly IRQF_NO_THREAD. =20 + shmem_anon=3D [KNL] + Format: [KMG],[KMG]:;[KMG]-[KMG]: + Control the default policy of each hugepage size for the + internal shmem mount. is one of policies available + for the shmem mount ("always", "inherit", "never", "within_size", + and "advise"). + It can be used multiple times for multiple shmem THP sizes. + See Documentation/admin-guide/mm/transhuge.rst for more + details. + topology=3D [S390,EARLY] Format: {off | on} Specify if the kernel should make use of the cpu diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/adm= in-guide/mm/transhuge.rst index 9b5b02c4d1ab..47e7fc30e22d 100644 --- a/Documentation/admin-guide/mm/transhuge.rst +++ b/Documentation/admin-guide/mm/transhuge.rst @@ -332,6 +332,23 @@ allocation policy for the internal shmem mount by usin= g the kernel parameter seven valid policies for shmem (``always``, ``within_size``, ``advise``, ``never``, ``deny``, and ``force``). =20 +In the same manner as ``thp_anon`` controls each supported anonymous THP +size, ``thp_shmem`` controls each supported shmem THP size. ``thp_shmem`` +has the same format as ``thp_anon``, but also supports the policy +``within_size``. + +``thp_shmem=3D`` may be specified multiple times to configure all THP sizes +as required. If ``thp_shmem=3D`` is specified at least once, any shmem THP +sizes not explicitly configured on the command line are implicitly set to +``never``. + +``transparent_hugepage_shmem`` setting only affects the global toggle. If +``thp_shmem`` is not specified, PMD_ORDER hugepage will default to +``inherit``. However, if a valid ``thp_shmem`` setting is provided by the +user, the PMD_ORDER hugepage policy will be overridden. If the policy for +PMD_ORDER is not defined within a valid ``thp_shmem``, its policy will +default to ``never``. + Hugepages in tmpfs/shmem =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =20 diff --git a/mm/shmem.c b/mm/shmem.c index 24cdeafd8260..0a7a7d04f725 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -136,6 +136,7 @@ static unsigned long huge_shmem_orders_always __read_mo= stly; static unsigned long huge_shmem_orders_madvise __read_mostly; static unsigned long huge_shmem_orders_inherit __read_mostly; static unsigned long huge_shmem_orders_within_size __read_mostly; +static bool shmem_orders_configured __initdata; #endif =20 #ifdef CONFIG_TMPFS @@ -5013,7 +5014,8 @@ void __init shmem_init(void) * Default to setting PMD-sized THP to inherit the global setting and * disable all other multi-size THPs. */ - huge_shmem_orders_inherit =3D BIT(HPAGE_PMD_ORDER); + if (!shmem_orders_configured) + huge_shmem_orders_inherit =3D BIT(HPAGE_PMD_ORDER); #endif return; =20 @@ -5174,6 +5176,26 @@ struct kobj_attribute thpsize_shmem_enabled_attr =3D =20 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) =20 +static inline int get_order_from_str(const char *size_str) +{ + unsigned long size; + char *endptr; + int order; + + size =3D memparse(size_str, &endptr); + + if (!is_power_of_2(size)) + goto err; + order =3D get_order(size); + if (BIT(order) & ~THP_ORDERS_ALL_FILE_DEFAULT) + goto err; + + return order; +err: + pr_err("invalid size %s in thp_shmem boot parameter\n", size_str); + return -EINVAL; +} + static int __init setup_transparent_hugepage_shmem(char *str) { int huge, ret =3D 0; @@ -5206,6 +5228,91 @@ static int __init setup_transparent_hugepage_shmem(c= har *str) } __setup("transparent_hugepage_shmem=3D", setup_transparent_hugepage_shmem); =20 +static char str_dup[PAGE_SIZE] __initdata; +static int __init setup_thp_shmem(char *str) +{ + char *token, *range, *policy, *subtoken; + unsigned long always, inherit, madvise, within_size; + char *start_size, *end_size; + int start, end, nr; + char *p; + + if (!str || strlen(str) + 1 > PAGE_SIZE) + goto err; + strcpy(str_dup, str); + + always =3D huge_shmem_orders_always; + inherit =3D huge_shmem_orders_inherit; + madvise =3D huge_shmem_orders_madvise; + within_size =3D huge_shmem_orders_within_size; + p =3D str_dup; + while ((token =3D strsep(&p, ";")) !=3D NULL) { + range =3D strsep(&token, ":"); + policy =3D token; + + if (!policy) + goto err; + + while ((subtoken =3D strsep(&range, ",")) !=3D NULL) { + if (strchr(subtoken, '-')) { + start_size =3D strsep(&subtoken, "-"); + end_size =3D subtoken; + + start =3D get_order_from_str(start_size); + end =3D get_order_from_str(end_size); + } else { + start =3D end =3D get_order_from_str(subtoken); + } + + if (start < 0 || end < 0 || start > end) + goto err; + + nr =3D end - start + 1; + if (!strcmp(policy, "always")) { + bitmap_set(&always, start, nr); + bitmap_clear(&inherit, start, nr); + bitmap_clear(&madvise, start, nr); + bitmap_clear(&within_size, start, nr); + } else if (!strcmp(policy, "advise")) { + bitmap_set(&madvise, start, nr); + bitmap_clear(&inherit, start, nr); + bitmap_clear(&always, start, nr); + bitmap_clear(&within_size, start, nr); + } else if (!strcmp(policy, "inherit")) { + bitmap_set(&inherit, start, nr); + bitmap_clear(&madvise, start, nr); + bitmap_clear(&always, start, nr); + bitmap_clear(&within_size, start, nr); + } else if (!strcmp(policy, "within_size")) { + bitmap_set(&within_size, start, nr); + bitmap_clear(&inherit, start, nr); + bitmap_clear(&madvise, start, nr); + bitmap_clear(&always, start, nr); + } else if (!strcmp(policy, "never")) { + bitmap_clear(&inherit, start, nr); + bitmap_clear(&madvise, start, nr); + bitmap_clear(&always, start, nr); + bitmap_clear(&within_size, start, nr); + } else { + pr_err("invalid policy %s in thp_shmem boot parameter\n", policy); + goto err; + } + } + } + + huge_shmem_orders_always =3D always; + huge_shmem_orders_madvise =3D madvise; + huge_shmem_orders_inherit =3D inherit; + huge_shmem_orders_within_size =3D within_size; + shmem_orders_configured =3D true; + return 1; + +err: + pr_warn("thp_shmem=3D%s: error parsing string, ignoring setting\n", str); + return 0; +} +__setup("thp_shmem=3D", setup_thp_shmem); + #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ =20 #else /* !CONFIG_SHMEM */ --=20 2.46.2