From patchwork Mon Jan 27 23:58:21 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13951916 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41D7BC0218A for ; Mon, 27 Jan 2025 23:58:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BEADE2801D2; Mon, 27 Jan 2025 18:58:29 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B9B652801D0; Mon, 27 Jan 2025 18:58:29 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A3BAC2801D2; Mon, 27 Jan 2025 18:58:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 82E802801D0 for ; Mon, 27 Jan 2025 18:58:29 -0500 (EST) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 3C644808BE for ; Mon, 27 Jan 2025 23:58:29 +0000 (UTC) X-FDA: 83054898738.13.F98A2B5 Received: from out-188.mta1.migadu.com (out-188.mta1.migadu.com [95.215.58.188]) by imf22.hostedemail.com (Postfix) with ESMTP id 93765C0002 for ; Mon, 27 Jan 2025 23:58:27 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=mop0t27e; spf=pass (imf22.hostedemail.com: domain of yosry.ahmed@linux.dev designates 95.215.58.188 as permitted sender) smtp.mailfrom=yosry.ahmed@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738022307; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding:in-reply-to: references:dkim-signature; bh=EPs2Uumgwh7vfBYo0WttnFq3NwRPbFFMOoiBXTDN20M=; b=kila7wj2CVQWwxV66eucoKb83mPBnegsoI7OgoSYx8Dl0LtFy4qJUtUM6Z2goUHOxVJRtC GPyHNj7hFGmqhcAysuJumY8nBreQVUGZfkgKNMUZlq1FkOk7q6xAj+49DkMKN3uB7pNi57 SvXSrNiJ1DR6hM4xR+zBaiWCXr2Lmog= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=mop0t27e; spf=pass (imf22.hostedemail.com: domain of yosry.ahmed@linux.dev designates 95.215.58.188 as permitted sender) smtp.mailfrom=yosry.ahmed@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738022307; a=rsa-sha256; cv=none; b=1WwPD9UL08Gm9sqORPEM52uDuKgdgAU6GC/7jxbLA+QntS99M80Du0pIwLyP8EkV65b8UF TEoGsOoLsV5L9Dh4Yve8aXftRt1XETyOc4g/3WwqDZGkgSKCwaLDThxm1sjGQxECKF5E+o 3+6eHMtGL6kFTkGMPqU/qo9zySu1wA0= Date: Mon, 27 Jan 2025 23:58:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1738022306; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=EPs2Uumgwh7vfBYo0WttnFq3NwRPbFFMOoiBXTDN20M=; b=mop0t27e59d7Z63k1Y1+pYSX8oRmad5uJCwuZSkAt0858KbChIwYTDFFj3IEuwwnl0VIrb jOYSA3Y+YBa8rXiIfZSBW6G6Kvppy6PkrvENViR+lCFK7xQbnoLW7M7CBGUvscRC2OC8vy k9sT3EmvzEKtp5vPYDJ1TRXiSOhgMhg= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yosry Ahmed To: Andrew Morton Cc: Vitaly Wool , Miaohe Lin , Johannes Weiner , Nhat Pham , Chengming Zhou , Huacai Chen , WANG Xuerui , linux-mm@kvack.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev Subject: [PATCH 1/2] mm: zbud: deprecate CONFIG_ZBUD Message-ID: MIME-Version: 1.0 Content-Disposition: inline X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 93765C0002 X-Stat-Signature: oku5n1prnbh34mjpef8djm8e7jfpdmy1 X-Rspam-User: X-HE-Tag: 1738022307-87811 X-HE-Meta: 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 bZ+BgRg/ EhtioBjmDEl8d3LciL4U+WxQ4e/Ctj6eR7RvQ8dXDazlPHOFvjOqs9YuYq8j61CDj7FcPpV5+QgY2Ihd7sVIhre7CtEmWs+6XOLnn7lnw8sDSlhH8NXYQLsIBFAC9MUGF3V6S9bOueiXxQMYJyVj+u0d+qRx1CsK1+KaKdAQ6IK6xjDJp9DnuPjheCRwFJ9fVWs3D1HCQuoOw5CY/wKDt9paT2Dsx4tc35NPzw2RjzDVnqtHCuEJ7xvTDcQ8wNNU7mM+L8uxRY3sGDVFxCSWI13k7SzkSTDN6D018DxWnISmLzcud3MyscNZWpcn44o0ohcYQNm/QMtSbqmQjMfzuUbqaDjVm5xT71NWgYLWe6gST2+E= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: The zbud compressed pages allocator is rarely used, most users use zsmalloc. zbud consumes much more memory (only stores 1 or 2 compressed pages per physical page). The only advantage of zbud is a marginal performance improvement that by no means justify the memory overhead. Historically, zsmalloc had significantly worse latency than zbud and z3fold but offered better memory savings. This is no longer the case as shown by a simple recent analysis [1]. In a kernel build test on tmpfs in a limited cgroup, zbud 2-3% less time than zsmalloc, but at the cost of using ~32% more memory (1.5G vs 1.13G). The tradeoff does not make sense for zbud in any practical scenario. The only alleged advantage of zbud is not having the dependency on CONFIG_MMU, but CONFIG_SWAP already depends on CONFIG_MMU anyway, and zbud is only used by zswap. Following in the footsteps of [2], which deprecated z3fold, deprecated zbud as planned and remove it in a few cycles if no objections are raised from active users. Rename the user-visible config options so that users with CONFIG_ZBUD=y get a new prompt with explanation during make oldconfig. Also, remove CONFIG_ZBUD from defconfig. [1]https://lore.kernel.org/lkml/CAJD7tkbRF6od-2x_L8-A1QL3=2Ww13sCj4S3i4bNndqF+3+_Vg@mail.gmail.com/ [2]https://lore.kernel.org/lkml/20240904233343.933462-1-yosryahmed@google.com/ Signed-off-by: Yosry Ahmed Reviewed-by: Shakeel Butt Acked-by: Nhat Pham --- arch/loongarch/configs/loongson3_defconfig | 3 +-- mm/Kconfig | 26 ++++++++++++++++------ 2 files changed, 20 insertions(+), 9 deletions(-) diff --git a/arch/loongarch/configs/loongson3_defconfig b/arch/loongarch/configs/loongson3_defconfig index 73c77500ac467..7ce5beb3cbf34 100644 --- a/arch/loongarch/configs/loongson3_defconfig +++ b/arch/loongarch/configs/loongson3_defconfig @@ -109,8 +109,7 @@ CONFIG_BINFMT_MISC=m CONFIG_ZPOOL=y CONFIG_ZSWAP=y CONFIG_ZSWAP_COMPRESSOR_DEFAULT_ZSTD=y -CONFIG_ZBUD=y -CONFIG_ZSMALLOC=m +CONFIG_ZSMALLOC=y # CONFIG_COMPAT_BRK is not set CONFIG_MEMORY_HOTPLUG=y # CONFIG_MHP_DEFAULT_ONLINE_TYPE_OFFLINE is not set diff --git a/mm/Kconfig b/mm/Kconfig index 1b501db064172..e3e15ab0cba49 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -129,7 +129,6 @@ choice prompt "Default allocator" depends on ZSWAP default ZSWAP_ZPOOL_DEFAULT_ZSMALLOC if MMU - default ZSWAP_ZPOOL_DEFAULT_ZBUD help Selects the default allocator for the compressed cache for swap pages. @@ -140,12 +139,15 @@ choice The selection made here can be overridden by using the kernel command line 'zswap.zpool=' option. -config ZSWAP_ZPOOL_DEFAULT_ZBUD - bool "zbud" - select ZBUD +config ZSWAP_ZPOOL_DEFAULT_ZBUD_DEPRECATED + bool "zbud (DEPRECATED)" + select ZBUD_DEPRECATED help Use the zbud allocator as the default allocator. + Deprecated and scheduled for removal in a few cycles, + see CONFIG_ZBUD_DEPRECATED. + config ZSWAP_ZPOOL_DEFAULT_Z3FOLD_DEPRECATED bool "z3foldi (DEPRECATED)" select Z3FOLD_DEPRECATED @@ -165,21 +167,31 @@ endchoice config ZSWAP_ZPOOL_DEFAULT string depends on ZSWAP - default "zbud" if ZSWAP_ZPOOL_DEFAULT_ZBUD + default "zbud" if ZSWAP_ZPOOL_DEFAULT_ZBUD_DEPRECATED default "z3fold" if ZSWAP_ZPOOL_DEFAULT_Z3FOLD_DEPRECATED default "zsmalloc" if ZSWAP_ZPOOL_DEFAULT_ZSMALLOC default "" -config ZBUD - tristate "2:1 compression allocator (zbud)" +config ZBUD_DEPRECATED + tristate "2:1 compression allocator (zbud) (DEPRECATED)" depends on ZSWAP help + Deprecated and scheduled for removal in a few cycles. If you have + a good reason for using ZBUD over ZSMALLOC, please contact + linux-mm@kvack.org and the zswap maintainers. + A special purpose allocator for storing compressed pages. It is designed to store up to two compressed pages per physical page. While this design limits storage density, it has simple and deterministic reclaim properties that make it preferable to a higher density approach when reclaim will be used. +config ZBUD + tristate + default y if ZBUD_DEPRECATED=y + default m if ZBUD_DEPRECATED=m + depends on ZBUD_DEPRECATED + config Z3FOLD_DEPRECATED tristate "3:1 compression allocator (z3fold) (DEPRECATED)" depends on ZSWAP From patchwork Mon Jan 27 23:58:29 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13951917 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 391EEC0218A for ; Mon, 27 Jan 2025 23:58:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B01E52801D3; Mon, 27 Jan 2025 18:58:38 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A89182801D0; Mon, 27 Jan 2025 18:58:38 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8B5B02801D3; Mon, 27 Jan 2025 18:58:38 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 580752801D0 for ; Mon, 27 Jan 2025 18:58:38 -0500 (EST) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 03E041408D4 for ; Mon, 27 Jan 2025 23:58:37 +0000 (UTC) X-FDA: 83054899116.18.6B0A32A Received: from out-180.mta1.migadu.com (out-180.mta1.migadu.com [95.215.58.180]) by imf01.hostedemail.com (Postfix) with ESMTP id 0A1954000F for ; Mon, 27 Jan 2025 23:58:35 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=gWD7yFy4; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf01.hostedemail.com: domain of yosry.ahmed@linux.dev designates 95.215.58.180 as permitted sender) smtp.mailfrom=yosry.ahmed@linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738022316; a=rsa-sha256; cv=none; b=rWh1656qpW3dqCI8vPS/A5KphMszGtuZzT838XdDRqQ6lmGF26ykU9qoyEtCq5MaxB83at jlbqM77JC/H4NfcP10tAK8ZQ//8wGjIHr18Y6xlXOj+JH7iQZIL7uwt84dxbRRuJqqEvlb E68c99scSMlO/s8+Wi47MFz3XydGspE= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=gWD7yFy4; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf01.hostedemail.com: domain of yosry.ahmed@linux.dev designates 95.215.58.180 as permitted sender) smtp.mailfrom=yosry.ahmed@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738022316; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:in-reply-to: references:dkim-signature; bh=DllK5GzekmYlTz0pzp/TiUo6/YecWa3mTwm7dBs/FPs=; b=WAt8fjIYw/RqGfOkCVvmbMwKl0vwD4TW6LpMROX5ISpSCQ2r2jNbusehOIHs8G56uXzw2A j95kGFqOUIvzgo3RZ+ukgNMUacn7GOXHMoUCSBX/xhoUIhioONTRPcgfUAookva5fxL7kQ NZyvnrB7JMR3qRHXOginISj63jgOJy0= Date: Mon, 27 Jan 2025 23:58:29 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1738022314; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=DllK5GzekmYlTz0pzp/TiUo6/YecWa3mTwm7dBs/FPs=; b=gWD7yFy46EnuU8m4BtkdLmpITj9g2tephBtHhKWNWhSyl/vdyDN1GjMNxvl3wvvYdRq00k ZKYON3xfTaByC7G8b07ajZ9/ltHIBr00p7xrEIb8al5Yw2/pizMh3m7Ax8E4jcVsw3GFaM TUEzeNniO5xX/dAwLw/Hl4e6n2v0/Mc= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yosry Ahmed To: Andrew Morton Cc: Vitaly Wool , Miaohe Lin , Johannes Weiner , Nhat Pham , Chengming Zhou , Huacai Chen , WANG Xuerui , linux-mm@kvack.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev Subject: [PATCH 2/2] mm: z3fold: remove z3fold Message-ID: MIME-Version: 1.0 Content-Disposition: inline X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 0A1954000F X-Stat-Signature: 34sjursrewzh6gwkae9ryo33itwn5sfr X-Rspam-User: X-HE-Tag: 1738022315-430553 X-HE-Meta: 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 rKsW9ZY9 zbQRikEK31ZqzAesu/Wz1YPcUvijC7zpymoKdzZ9rI6XBZA7cHEEZAY3zZHM/6iDtTrm4wUVI8m3Q6tCNviNSvcDuOBozpJSS8etvS43cjhfnVc4/a6EE4idMAtlMfmdErAkuwDLQkC9RGzR0Q7SUgztiFxUsFaPAlkyqoWenzgfOXQ7SEHi9/t7GOmuWgn+HengJU5w6FXOylzCDigjtycVMl+pnzVjCRCtB3SheL3DuyoLiCgKEEi02uNAPDMvWEtoJm+ZAdXGtSUT+pJ+WcCwveQhff2lVo29Pc1Ijmnbxy1z9+gCWBP62JLopv6skJmIYpdLZEWSUdt0khDWD4bRcnJSJDslU2IxWhGSONSP2GZeGQD/VuxBgXp+wZm8aorO1TsFXuNMs79AS11DlxRs+xWswnWrLCKllOzYc6Yw8Sf8IqE2XpHBYu+/VRuWFVPLQWlU4rV+uexC8u2lkU5Mc32Y/OrdTH/xrph31LezWSK4= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Z3fold has been marked as deprecated for 2 cycles and no one complained, as expected. As there are no known users, remove the code now. Signed-off-by: Yosry Ahmed Acked-by: Johannes Weiner Reviewed-by: Shakeel Butt Acked-by: Nhat Pham --- CREDITS | 1 + Documentation/mm/index.rst | 1 - Documentation/mm/z3fold.rst | 28 - Documentation/translations/zh_CN/mm/index.rst | 1 - .../translations/zh_CN/mm/z3fold.rst | 31 - MAINTAINERS | 7 - mm/Kconfig | 29 - mm/Makefile | 1 - mm/z3fold.c | 1447 ----------------- 9 files changed, 1 insertion(+), 1545 deletions(-) delete mode 100644 Documentation/mm/z3fold.rst delete mode 100644 Documentation/translations/zh_CN/mm/z3fold.rst delete mode 100644 mm/z3fold.c diff --git a/CREDITS b/CREDITS index 1f9f0f078b4ae..324428ad37e83 100644 --- a/CREDITS +++ b/CREDITS @@ -4313,6 +4313,7 @@ S: England N: Vitaly Wool E: vitaly.wool@konsulko.com D: Maintenance and development of zswap +D: Maintenance and development of z3fold N: Chris Wright E: chrisw@sous-sol.org diff --git a/Documentation/mm/index.rst b/Documentation/mm/index.rst index 0be1c7503a010..d3ada3e45e103 100644 --- a/Documentation/mm/index.rst +++ b/Documentation/mm/index.rst @@ -62,5 +62,4 @@ documentation, or deleted if it has served its purpose. unevictable-lru vmalloced-kernel-stacks vmemmap_dedup - z3fold zsmalloc diff --git a/Documentation/mm/z3fold.rst b/Documentation/mm/z3fold.rst deleted file mode 100644 index 25b5935d06c7d..0000000000000 --- a/Documentation/mm/z3fold.rst +++ /dev/null @@ -1,28 +0,0 @@ -====== -z3fold -====== - -z3fold is a special purpose allocator for storing compressed pages. -It is designed to store up to three compressed pages per physical page. -It is a zbud derivative which allows for higher compression -ratio keeping the simplicity and determinism of its predecessor. - -The main differences between z3fold and zbud are: - -* unlike zbud, z3fold allows for up to PAGE_SIZE allocations -* z3fold can hold up to 3 compressed pages in its page -* z3fold doesn't export any API itself and is thus intended to be used - via the zpool API. - -To keep the determinism and simplicity, z3fold, just like zbud, always -stores an integral number of compressed pages per page, but it can store -up to 3 pages unlike zbud which can store at most 2. Therefore the -compression ratio goes to around 2.7x while zbud's one is around 1.7x. - -Unlike zbud (but like zsmalloc for that matter) z3fold_alloc() does not -return a dereferenceable pointer. Instead, it returns an unsigned long -handle which encodes actual location of the allocated object. - -Keeping effective compression ratio close to zsmalloc's, z3fold doesn't -depend on MMU enabled and provides more predictable reclaim behavior -which makes it a better fit for small and response-critical systems. diff --git a/Documentation/translations/zh_CN/mm/index.rst b/Documentation/translations/zh_CN/mm/index.rst index c8726bce8f745..a71116be058fd 100644 --- a/Documentation/translations/zh_CN/mm/index.rst +++ b/Documentation/translations/zh_CN/mm/index.rst @@ -58,7 +58,6 @@ Linux内存管理文档 remap_file_pages split_page_table_lock vmalloced-kernel-stacks - z3fold zsmalloc TODOLIST: diff --git a/Documentation/translations/zh_CN/mm/z3fold.rst b/Documentation/translations/zh_CN/mm/z3fold.rst deleted file mode 100644 index 9569a6d882700..0000000000000 --- a/Documentation/translations/zh_CN/mm/z3fold.rst +++ /dev/null @@ -1,31 +0,0 @@ -:Original: Documentation/mm/z3fold.rst - -:翻译: - - 司延腾 Yanteng Si - -:校译: - - -====== -z3fold -====== - -z3fold是一个专门用于存储压缩页的分配器。它被设计为每个物理页最多可以存储三个压缩页。 -它是zbud的衍生物，允许更高的压缩率，保持其前辈的简单性和确定性。 - -z3fold和zbud的主要区别是: - -* 与zbud不同的是，z3fold允许最大的PAGE_SIZE分配。 -* z3fold在其页面中最多可以容纳3个压缩页面 -* z3fold本身没有输出任何API，因此打算通过zpool的API来使用 - -为了保持确定性和简单性，z3fold，就像zbud一样，总是在每页存储一个整数的压缩页，但是 -它最多可以存储3页，不像zbud最多可以存储2页。因此压缩率达到2.7倍左右，而zbud的压缩 -率是1.7倍左右。 - -不像zbud（但也像zsmalloc），z3fold_alloc()那样不返回一个可重复引用的指针。相反，它 -返回一个无符号长句柄，它编码了被分配对象的实际位置。 - -保持有效的压缩率接近于zsmalloc，z3fold不依赖于MMU的启用，并提供更可预测的回收行 -为，这使得它更适合于小型和反应迅速的系统。 diff --git a/MAINTAINERS b/MAINTAINERS index feed152470f68..1583bb8eee587 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -26055,13 +26055,6 @@ S: Maintained F: Documentation/input/devices/yealink.rst F: drivers/input/misc/yealink.* -Z3FOLD COMPRESSED PAGE ALLOCATOR -M: Vitaly Wool -R: Miaohe Lin -L: linux-mm@kvack.org -S: Maintained -F: mm/z3fold.c - Z8530 DRIVER FOR AX.25 M: Joerg Reuter L: linux-hams@vger.kernel.org diff --git a/mm/Kconfig b/mm/Kconfig index e3e15ab0cba49..1d27e037ab24a 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -148,15 +148,6 @@ config ZSWAP_ZPOOL_DEFAULT_ZBUD_DEPRECATED Deprecated and scheduled for removal in a few cycles, see CONFIG_ZBUD_DEPRECATED. -config ZSWAP_ZPOOL_DEFAULT_Z3FOLD_DEPRECATED - bool "z3foldi (DEPRECATED)" - select Z3FOLD_DEPRECATED - help - Use the z3fold allocator as the default allocator. - - Deprecated and scheduled for removal in a few cycles, - see CONFIG_Z3FOLD_DEPRECATED. - config ZSWAP_ZPOOL_DEFAULT_ZSMALLOC bool "zsmalloc" select ZSMALLOC @@ -168,7 +159,6 @@ config ZSWAP_ZPOOL_DEFAULT string depends on ZSWAP default "zbud" if ZSWAP_ZPOOL_DEFAULT_ZBUD_DEPRECATED - default "z3fold" if ZSWAP_ZPOOL_DEFAULT_Z3FOLD_DEPRECATED default "zsmalloc" if ZSWAP_ZPOOL_DEFAULT_ZSMALLOC default "" @@ -192,25 +182,6 @@ config ZBUD default m if ZBUD_DEPRECATED=m depends on ZBUD_DEPRECATED -config Z3FOLD_DEPRECATED - tristate "3:1 compression allocator (z3fold) (DEPRECATED)" - depends on ZSWAP - help - Deprecated and scheduled for removal in a few cycles. If you have - a good reason for using Z3FOLD over ZSMALLOC, please contact - linux-mm@kvack.org and the zswap maintainers. - - A special purpose allocator for storing compressed pages. - It is designed to store up to three compressed pages per physical - page. It is a ZBUD derivative so the simplicity and determinism are - still there. - -config Z3FOLD - tristate - default y if Z3FOLD_DEPRECATED=y - default m if Z3FOLD_DEPRECATED=m - depends on Z3FOLD_DEPRECATED - config ZSMALLOC tristate prompt "N:1 compression allocator (zsmalloc)" if (ZSWAP || ZRAM) diff --git a/mm/Makefile b/mm/Makefile index 850386a67b3e0..e4c03da3c0846 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -115,7 +115,6 @@ obj-$(CONFIG_MEMORY_ISOLATION) += page_isolation.o obj-$(CONFIG_ZPOOL) += zpool.o obj-$(CONFIG_ZBUD) += zbud.o obj-$(CONFIG_ZSMALLOC) += zsmalloc.o -obj-$(CONFIG_Z3FOLD) += z3fold.o obj-$(CONFIG_GENERIC_EARLY_IOREMAP) += early_ioremap.o obj-$(CONFIG_CMA) += cma.o obj-$(CONFIG_NUMA) += numa.o diff --git a/mm/z3fold.c b/mm/z3fold.c deleted file mode 100644 index 379d24b4fef99..0000000000000 --- a/mm/z3fold.c +++ /dev/null @@ -1,1447 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * z3fold.c - * - * Author: Vitaly Wool - * Copyright (C) 2016, Sony Mobile Communications Inc. - * - * This implementation is based on zbud written by Seth Jennings. - * - * z3fold is an special purpose allocator for storing compressed pages. It - * can store up to three compressed pages per page which improves the - * compression ratio of zbud while retaining its main concepts (e. g. always - * storing an integral number of objects per page) and simplicity. - * It still has simple and deterministic reclaim properties that make it - * preferable to a higher density approach (with no requirement on integral - * number of object per page) when reclaim is used. - * - * As in zbud, pages are divided into "chunks". The size of the chunks is - * fixed at compile time and is determined by NCHUNKS_ORDER below. - * - * z3fold doesn't export any API and is meant to be used via zpool API. - */ - -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* - * NCHUNKS_ORDER determines the internal allocation granularity, effectively - * adjusting internal fragmentation. It also determines the number of - * freelists maintained in each pool. NCHUNKS_ORDER of 6 means that the - * allocation granularity will be in chunks of size PAGE_SIZE/64. Some chunks - * in the beginning of an allocated page are occupied by z3fold header, so - * NCHUNKS will be calculated to 63 (or 62 in case CONFIG_DEBUG_SPINLOCK=y), - * which shows the max number of free chunks in z3fold page, also there will - * be 63, or 62, respectively, freelists per pool. - */ -#define NCHUNKS_ORDER 6 - -#define CHUNK_SHIFT (PAGE_SHIFT - NCHUNKS_ORDER) -#define CHUNK_SIZE (1 << CHUNK_SHIFT) -#define ZHDR_SIZE_ALIGNED round_up(sizeof(struct z3fold_header), CHUNK_SIZE) -#define ZHDR_CHUNKS (ZHDR_SIZE_ALIGNED >> CHUNK_SHIFT) -#define TOTAL_CHUNKS (PAGE_SIZE >> CHUNK_SHIFT) -#define NCHUNKS (TOTAL_CHUNKS - ZHDR_CHUNKS) - -#define BUDDY_MASK (0x3) -#define BUDDY_SHIFT 2 -#define SLOTS_ALIGN (0x40) - -/***************** - * Structures -*****************/ -struct z3fold_pool; - -enum buddy { - HEADLESS = 0, - FIRST, - MIDDLE, - LAST, - BUDDIES_MAX = LAST -}; - -struct z3fold_buddy_slots { - /* - * we are using BUDDY_MASK in handle_to_buddy etc. so there should - * be enough slots to hold all possible variants - */ - unsigned long slot[BUDDY_MASK + 1]; - unsigned long pool; /* back link */ - rwlock_t lock; -}; -#define HANDLE_FLAG_MASK (0x03) - -/* - * struct z3fold_header - z3fold page metadata occupying first chunks of each - * z3fold page, except for HEADLESS pages - * @buddy: links the z3fold page into the relevant list in the - * pool - * @page_lock: per-page lock - * @refcount: reference count for the z3fold page - * @work: work_struct for page layout optimization - * @slots: pointer to the structure holding buddy slots - * @pool: pointer to the containing pool - * @cpu: CPU which this page "belongs" to - * @first_chunks: the size of the first buddy in chunks, 0 if free - * @middle_chunks: the size of the middle buddy in chunks, 0 if free - * @last_chunks: the size of the last buddy in chunks, 0 if free - * @first_num: the starting number (for the first handle) - * @mapped_count: the number of objects currently mapped - */ -struct z3fold_header { - struct list_head buddy; - spinlock_t page_lock; - struct kref refcount; - struct work_struct work; - struct z3fold_buddy_slots *slots; - struct z3fold_pool *pool; - short cpu; - unsigned short first_chunks; - unsigned short middle_chunks; - unsigned short last_chunks; - unsigned short start_middle; - unsigned short first_num:2; - unsigned short mapped_count:2; - unsigned short foreign_handles:2; -}; - -/** - * struct z3fold_pool - stores metadata for each z3fold pool - * @name: pool name - * @lock: protects pool unbuddied lists - * @stale_lock: protects pool stale page list - * @unbuddied: per-cpu array of lists tracking z3fold pages that contain 2- - * buddies; the list each z3fold page is added to depends on - * the size of its free region. - * @stale: list of pages marked for freeing - * @pages_nr: number of z3fold pages in the pool. - * @c_handle: cache for z3fold_buddy_slots allocation - * @compact_wq: workqueue for page layout background optimization - * @release_wq: workqueue for safe page release - * @work: work_struct for safe page release - * - * This structure is allocated at pool creation time and maintains metadata - * pertaining to a particular z3fold pool. - */ -struct z3fold_pool { - const char *name; - spinlock_t lock; - spinlock_t stale_lock; - struct list_head __percpu *unbuddied; - struct list_head stale; - atomic64_t pages_nr; - struct kmem_cache *c_handle; - struct workqueue_struct *compact_wq; - struct workqueue_struct *release_wq; - struct work_struct work; -}; - -/* - * Internal z3fold page flags - */ -enum z3fold_page_flags { - PAGE_HEADLESS = 0, - MIDDLE_CHUNK_MAPPED, - NEEDS_COMPACTING, - PAGE_STALE, - PAGE_CLAIMED, /* by either reclaim or free */ - PAGE_MIGRATED, /* page is migrated and soon to be released */ -}; - -/* - * handle flags, go under HANDLE_FLAG_MASK - */ -enum z3fold_handle_flags { - HANDLES_NOFREE = 0, -}; - -/* - * Forward declarations - */ -static struct z3fold_header *__z3fold_alloc(struct z3fold_pool *, size_t, bool); -static void compact_page_work(struct work_struct *w); - -/***************** - * Helpers -*****************/ - -/* Converts an allocation size in bytes to size in z3fold chunks */ -static int size_to_chunks(size_t size) -{ - return (size + CHUNK_SIZE - 1) >> CHUNK_SHIFT; -} - -#define for_each_unbuddied_list(_iter, _begin) \ - for ((_iter) = (_begin); (_iter) < NCHUNKS; (_iter)++) - -static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool, - gfp_t gfp) -{ - struct z3fold_buddy_slots *slots = kmem_cache_zalloc(pool->c_handle, - gfp); - - if (slots) { - /* It will be freed separately in free_handle(). */ - kmemleak_not_leak(slots); - slots->pool = (unsigned long)pool; - rwlock_init(&slots->lock); - } - - return slots; -} - -static inline struct z3fold_pool *slots_to_pool(struct z3fold_buddy_slots *s) -{ - return (struct z3fold_pool *)(s->pool & ~HANDLE_FLAG_MASK); -} - -static inline struct z3fold_buddy_slots *handle_to_slots(unsigned long handle) -{ - return (struct z3fold_buddy_slots *)(handle & ~(SLOTS_ALIGN - 1)); -} - -/* Lock a z3fold page */ -static inline void z3fold_page_lock(struct z3fold_header *zhdr) -{ - spin_lock(&zhdr->page_lock); -} - -/* Try to lock a z3fold page */ -static inline int z3fold_page_trylock(struct z3fold_header *zhdr) -{ - return spin_trylock(&zhdr->page_lock); -} - -/* Unlock a z3fold page */ -static inline void z3fold_page_unlock(struct z3fold_header *zhdr) -{ - spin_unlock(&zhdr->page_lock); -} - -/* return locked z3fold page if it's not headless */ -static inline struct z3fold_header *get_z3fold_header(unsigned long handle) -{ - struct z3fold_buddy_slots *slots; - struct z3fold_header *zhdr; - int locked = 0; - - if (!(handle & (1 << PAGE_HEADLESS))) { - slots = handle_to_slots(handle); - do { - unsigned long addr; - - read_lock(&slots->lock); - addr = *(unsigned long *)handle; - zhdr = (struct z3fold_header *)(addr & PAGE_MASK); - locked = z3fold_page_trylock(zhdr); - read_unlock(&slots->lock); - if (locked) { - struct page *page = virt_to_page(zhdr); - - if (!test_bit(PAGE_MIGRATED, &page->private)) - break; - z3fold_page_unlock(zhdr); - } - cpu_relax(); - } while (true); - } else { - zhdr = (struct z3fold_header *)(handle & PAGE_MASK); - } - - return zhdr; -} - -static inline void put_z3fold_header(struct z3fold_header *zhdr) -{ - struct page *page = virt_to_page(zhdr); - - if (!test_bit(PAGE_HEADLESS, &page->private)) - z3fold_page_unlock(zhdr); -} - -static inline void free_handle(unsigned long handle, struct z3fold_header *zhdr) -{ - struct z3fold_buddy_slots *slots; - int i; - bool is_free; - - if (WARN_ON(*(unsigned long *)handle == 0)) - return; - - slots = handle_to_slots(handle); - write_lock(&slots->lock); - *(unsigned long *)handle = 0; - - if (test_bit(HANDLES_NOFREE, &slots->pool)) { - write_unlock(&slots->lock); - return; /* simple case, nothing else to do */ - } - - if (zhdr->slots != slots) - zhdr->foreign_handles--; - - is_free = true; - for (i = 0; i <= BUDDY_MASK; i++) { - if (slots->slot[i]) { - is_free = false; - break; - } - } - write_unlock(&slots->lock); - - if (is_free) { - struct z3fold_pool *pool = slots_to_pool(slots); - - if (zhdr->slots == slots) - zhdr->slots = NULL; - kmem_cache_free(pool->c_handle, slots); - } -} - -/* Initializes the z3fold header of a newly allocated z3fold page */ -static struct z3fold_header *init_z3fold_page(struct page *page, bool headless, - struct z3fold_pool *pool, gfp_t gfp) -{ - struct z3fold_header *zhdr = page_address(page); - struct z3fold_buddy_slots *slots; - - clear_bit(PAGE_HEADLESS, &page->private); - clear_bit(MIDDLE_CHUNK_MAPPED, &page->private); - clear_bit(NEEDS_COMPACTING, &page->private); - clear_bit(PAGE_STALE, &page->private); - clear_bit(PAGE_CLAIMED, &page->private); - clear_bit(PAGE_MIGRATED, &page->private); - if (headless) - return zhdr; - - slots = alloc_slots(pool, gfp); - if (!slots) - return NULL; - - memset(zhdr, 0, sizeof(*zhdr)); - spin_lock_init(&zhdr->page_lock); - kref_init(&zhdr->refcount); - zhdr->cpu = -1; - zhdr->slots = slots; - zhdr->pool = pool; - INIT_LIST_HEAD(&zhdr->buddy); - INIT_WORK(&zhdr->work, compact_page_work); - return zhdr; -} - -/* Resets the struct page fields and frees the page */ -static void free_z3fold_page(struct page *page, bool headless) -{ - if (!headless) { - lock_page(page); - __ClearPageMovable(page); - unlock_page(page); - } - __free_page(page); -} - -/* Helper function to build the index */ -static inline int __idx(struct z3fold_header *zhdr, enum buddy bud) -{ - return (bud + zhdr->first_num) & BUDDY_MASK; -} - -/* - * Encodes the handle of a particular buddy within a z3fold page. - * Zhdr->page_lock should be held as this function accesses first_num - * if bud != HEADLESS. - */ -static unsigned long __encode_handle(struct z3fold_header *zhdr, - struct z3fold_buddy_slots *slots, - enum buddy bud) -{ - unsigned long h = (unsigned long)zhdr; - int idx = 0; - - /* - * For a headless page, its handle is its pointer with the extra - * PAGE_HEADLESS bit set - */ - if (bud == HEADLESS) - return h | (1 << PAGE_HEADLESS); - - /* otherwise, return pointer to encoded handle */ - idx = __idx(zhdr, bud); - h += idx; - if (bud == LAST) - h |= (zhdr->last_chunks << BUDDY_SHIFT); - - write_lock(&slots->lock); - slots->slot[idx] = h; - write_unlock(&slots->lock); - return (unsigned long)&slots->slot[idx]; -} - -static unsigned long encode_handle(struct z3fold_header *zhdr, enum buddy bud) -{ - return __encode_handle(zhdr, zhdr->slots, bud); -} - -/* only for LAST bud, returns zero otherwise */ -static unsigned short handle_to_chunks(unsigned long handle) -{ - struct z3fold_buddy_slots *slots = handle_to_slots(handle); - unsigned long addr; - - read_lock(&slots->lock); - addr = *(unsigned long *)handle; - read_unlock(&slots->lock); - return (addr & ~PAGE_MASK) >> BUDDY_SHIFT; -} - -/* - * (handle & BUDDY_MASK) < zhdr->first_num is possible in encode_handle - * but that doesn't matter. because the masking will result in the - * correct buddy number. - */ -static enum buddy handle_to_buddy(unsigned long handle) -{ - struct z3fold_header *zhdr; - struct z3fold_buddy_slots *slots = handle_to_slots(handle); - unsigned long addr; - - read_lock(&slots->lock); - WARN_ON(handle & (1 << PAGE_HEADLESS)); - addr = *(unsigned long *)handle; - read_unlock(&slots->lock); - zhdr = (struct z3fold_header *)(addr & PAGE_MASK); - return (addr - zhdr->first_num) & BUDDY_MASK; -} - -static inline struct z3fold_pool *zhdr_to_pool(struct z3fold_header *zhdr) -{ - return zhdr->pool; -} - -static void __release_z3fold_page(struct z3fold_header *zhdr, bool locked) -{ - struct page *page = virt_to_page(zhdr); - struct z3fold_pool *pool = zhdr_to_pool(zhdr); - - WARN_ON(!list_empty(&zhdr->buddy)); - set_bit(PAGE_STALE, &page->private); - clear_bit(NEEDS_COMPACTING, &page->private); - spin_lock(&pool->lock); - spin_unlock(&pool->lock); - - if (locked) - z3fold_page_unlock(zhdr); - - spin_lock(&pool->stale_lock); - list_add(&zhdr->buddy, &pool->stale); - queue_work(pool->release_wq, &pool->work); - spin_unlock(&pool->stale_lock); - - atomic64_dec(&pool->pages_nr); -} - -static void release_z3fold_page_locked(struct kref *ref) -{ - struct z3fold_header *zhdr = container_of(ref, struct z3fold_header, - refcount); - WARN_ON(z3fold_page_trylock(zhdr)); - __release_z3fold_page(zhdr, true); -} - -static void release_z3fold_page_locked_list(struct kref *ref) -{ - struct z3fold_header *zhdr = container_of(ref, struct z3fold_header, - refcount); - struct z3fold_pool *pool = zhdr_to_pool(zhdr); - - spin_lock(&pool->lock); - list_del_init(&zhdr->buddy); - spin_unlock(&pool->lock); - - WARN_ON(z3fold_page_trylock(zhdr)); - __release_z3fold_page(zhdr, true); -} - -static inline int put_z3fold_locked(struct z3fold_header *zhdr) -{ - return kref_put(&zhdr->refcount, release_z3fold_page_locked); -} - -static inline int put_z3fold_locked_list(struct z3fold_header *zhdr) -{ - return kref_put(&zhdr->refcount, release_z3fold_page_locked_list); -} - -static void free_pages_work(struct work_struct *w) -{ - struct z3fold_pool *pool = container_of(w, struct z3fold_pool, work); - - spin_lock(&pool->stale_lock); - while (!list_empty(&pool->stale)) { - struct z3fold_header *zhdr = list_first_entry(&pool->stale, - struct z3fold_header, buddy); - struct page *page = virt_to_page(zhdr); - - list_del(&zhdr->buddy); - if (WARN_ON(!test_bit(PAGE_STALE, &page->private))) - continue; - spin_unlock(&pool->stale_lock); - cancel_work_sync(&zhdr->work); - free_z3fold_page(page, false); - cond_resched(); - spin_lock(&pool->stale_lock); - } - spin_unlock(&pool->stale_lock); -} - -/* - * Returns the number of free chunks in a z3fold page. - * NB: can't be used with HEADLESS pages. - */ -static int num_free_chunks(struct z3fold_header *zhdr) -{ - int nfree; - /* - * If there is a middle object, pick up the bigger free space - * either before or after it. Otherwise just subtract the number - * of chunks occupied by the first and the last objects. - */ - if (zhdr->middle_chunks != 0) { - int nfree_before = zhdr->first_chunks ? - 0 : zhdr->start_middle - ZHDR_CHUNKS; - int nfree_after = zhdr->last_chunks ? - 0 : TOTAL_CHUNKS - - (zhdr->start_middle + zhdr->middle_chunks); - nfree = max(nfree_before, nfree_after); - } else - nfree = NCHUNKS - zhdr->first_chunks - zhdr->last_chunks; - return nfree; -} - -/* Add to the appropriate unbuddied list */ -static inline void add_to_unbuddied(struct z3fold_pool *pool, - struct z3fold_header *zhdr) -{ - if (zhdr->first_chunks == 0 || zhdr->last_chunks == 0 || - zhdr->middle_chunks == 0) { - struct list_head *unbuddied; - int freechunks = num_free_chunks(zhdr); - - migrate_disable(); - unbuddied = this_cpu_ptr(pool->unbuddied); - spin_lock(&pool->lock); - list_add(&zhdr->buddy, &unbuddied[freechunks]); - spin_unlock(&pool->lock); - zhdr->cpu = smp_processor_id(); - migrate_enable(); - } -} - -static inline enum buddy get_free_buddy(struct z3fold_header *zhdr, int chunks) -{ - enum buddy bud = HEADLESS; - - if (zhdr->middle_chunks) { - if (!zhdr->first_chunks && - chunks <= zhdr->start_middle - ZHDR_CHUNKS) - bud = FIRST; - else if (!zhdr->last_chunks) - bud = LAST; - } else { - if (!zhdr->first_chunks) - bud = FIRST; - else if (!zhdr->last_chunks) - bud = LAST; - else - bud = MIDDLE; - } - - return bud; -} - -static inline void *mchunk_memmove(struct z3fold_header *zhdr, - unsigned short dst_chunk) -{ - void *beg = zhdr; - return memmove(beg + (dst_chunk << CHUNK_SHIFT), - beg + (zhdr->start_middle << CHUNK_SHIFT), - zhdr->middle_chunks << CHUNK_SHIFT); -} - -static inline bool buddy_single(struct z3fold_header *zhdr) -{ - return !((zhdr->first_chunks && zhdr->middle_chunks) || - (zhdr->first_chunks && zhdr->last_chunks) || - (zhdr->middle_chunks && zhdr->last_chunks)); -} - -static struct z3fold_header *compact_single_buddy(struct z3fold_header *zhdr) -{ - struct z3fold_pool *pool = zhdr_to_pool(zhdr); - void *p = zhdr; - unsigned long old_handle = 0; - size_t sz = 0; - struct z3fold_header *new_zhdr = NULL; - int first_idx = __idx(zhdr, FIRST); - int middle_idx = __idx(zhdr, MIDDLE); - int last_idx = __idx(zhdr, LAST); - unsigned short *moved_chunks = NULL; - - /* - * No need to protect slots here -- all the slots are "local" and - * the page lock is already taken - */ - if (zhdr->first_chunks && zhdr->slots->slot[first_idx]) { - p += ZHDR_SIZE_ALIGNED; - sz = zhdr->first_chunks << CHUNK_SHIFT; - old_handle = (unsigned long)&zhdr->slots->slot[first_idx]; - moved_chunks = &zhdr->first_chunks; - } else if (zhdr->middle_chunks && zhdr->slots->slot[middle_idx]) { - p += zhdr->start_middle << CHUNK_SHIFT; - sz = zhdr->middle_chunks << CHUNK_SHIFT; - old_handle = (unsigned long)&zhdr->slots->slot[middle_idx]; - moved_chunks = &zhdr->middle_chunks; - } else if (zhdr->last_chunks && zhdr->slots->slot[last_idx]) { - p += PAGE_SIZE - (zhdr->last_chunks << CHUNK_SHIFT); - sz = zhdr->last_chunks << CHUNK_SHIFT; - old_handle = (unsigned long)&zhdr->slots->slot[last_idx]; - moved_chunks = &zhdr->last_chunks; - } - - if (sz > 0) { - enum buddy new_bud = HEADLESS; - short chunks = size_to_chunks(sz); - void *q; - - new_zhdr = __z3fold_alloc(pool, sz, false); - if (!new_zhdr) - return NULL; - - if (WARN_ON(new_zhdr == zhdr)) - goto out_fail; - - new_bud = get_free_buddy(new_zhdr, chunks); - q = new_zhdr; - switch (new_bud) { - case FIRST: - new_zhdr->first_chunks = chunks; - q += ZHDR_SIZE_ALIGNED; - break; - case MIDDLE: - new_zhdr->middle_chunks = chunks; - new_zhdr->start_middle = - new_zhdr->first_chunks + ZHDR_CHUNKS; - q += new_zhdr->start_middle << CHUNK_SHIFT; - break; - case LAST: - new_zhdr->last_chunks = chunks; - q += PAGE_SIZE - (new_zhdr->last_chunks << CHUNK_SHIFT); - break; - default: - goto out_fail; - } - new_zhdr->foreign_handles++; - memcpy(q, p, sz); - write_lock(&zhdr->slots->lock); - *(unsigned long *)old_handle = (unsigned long)new_zhdr + - __idx(new_zhdr, new_bud); - if (new_bud == LAST) - *(unsigned long *)old_handle |= - (new_zhdr->last_chunks << BUDDY_SHIFT); - write_unlock(&zhdr->slots->lock); - add_to_unbuddied(pool, new_zhdr); - z3fold_page_unlock(new_zhdr); - - *moved_chunks = 0; - } - - return new_zhdr; - -out_fail: - if (new_zhdr && !put_z3fold_locked(new_zhdr)) { - add_to_unbuddied(pool, new_zhdr); - z3fold_page_unlock(new_zhdr); - } - return NULL; - -} - -#define BIG_CHUNK_GAP 3 -/* Has to be called with lock held */ -static int z3fold_compact_page(struct z3fold_header *zhdr) -{ - struct page *page = virt_to_page(zhdr); - - if (test_bit(MIDDLE_CHUNK_MAPPED, &page->private)) - return 0; /* can't move middle chunk, it's used */ - - if (unlikely(PageIsolated(page))) - return 0; - - if (zhdr->middle_chunks == 0) - return 0; /* nothing to compact */ - - if (zhdr->first_chunks == 0 && zhdr->last_chunks == 0) { - /* move to the beginning */ - mchunk_memmove(zhdr, ZHDR_CHUNKS); - zhdr->first_chunks = zhdr->middle_chunks; - zhdr->middle_chunks = 0; - zhdr->start_middle = 0; - zhdr->first_num++; - return 1; - } - - /* - * moving data is expensive, so let's only do that if - * there's substantial gain (at least BIG_CHUNK_GAP chunks) - */ - if (zhdr->first_chunks != 0 && zhdr->last_chunks == 0 && - zhdr->start_middle - (zhdr->first_chunks + ZHDR_CHUNKS) >= - BIG_CHUNK_GAP) { - mchunk_memmove(zhdr, zhdr->first_chunks + ZHDR_CHUNKS); - zhdr->start_middle = zhdr->first_chunks + ZHDR_CHUNKS; - return 1; - } else if (zhdr->last_chunks != 0 && zhdr->first_chunks == 0 && - TOTAL_CHUNKS - (zhdr->last_chunks + zhdr->start_middle - + zhdr->middle_chunks) >= - BIG_CHUNK_GAP) { - unsigned short new_start = TOTAL_CHUNKS - zhdr->last_chunks - - zhdr->middle_chunks; - mchunk_memmove(zhdr, new_start); - zhdr->start_middle = new_start; - return 1; - } - - return 0; -} - -static void do_compact_page(struct z3fold_header *zhdr, bool locked) -{ - struct z3fold_pool *pool = zhdr_to_pool(zhdr); - struct page *page; - - page = virt_to_page(zhdr); - if (locked) - WARN_ON(z3fold_page_trylock(zhdr)); - else - z3fold_page_lock(zhdr); - if (WARN_ON(!test_and_clear_bit(NEEDS_COMPACTING, &page->private))) { - z3fold_page_unlock(zhdr); - return; - } - spin_lock(&pool->lock); - list_del_init(&zhdr->buddy); - spin_unlock(&pool->lock); - - if (put_z3fold_locked(zhdr)) - return; - - if (test_bit(PAGE_STALE, &page->private) || - test_and_set_bit(PAGE_CLAIMED, &page->private)) { - z3fold_page_unlock(zhdr); - return; - } - - if (!zhdr->foreign_handles && buddy_single(zhdr) && - zhdr->mapped_count == 0 && compact_single_buddy(zhdr)) { - if (!put_z3fold_locked(zhdr)) { - clear_bit(PAGE_CLAIMED, &page->private); - z3fold_page_unlock(zhdr); - } - return; - } - - z3fold_compact_page(zhdr); - add_to_unbuddied(pool, zhdr); - clear_bit(PAGE_CLAIMED, &page->private); - z3fold_page_unlock(zhdr); -} - -static void compact_page_work(struct work_struct *w) -{ - struct z3fold_header *zhdr = container_of(w, struct z3fold_header, - work); - - do_compact_page(zhdr, false); -} - -/* returns _locked_ z3fold page header or NULL */ -static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool, - size_t size, bool can_sleep) -{ - struct z3fold_header *zhdr = NULL; - struct page *page; - struct list_head *unbuddied; - int chunks = size_to_chunks(size), i; - -lookup: - migrate_disable(); - /* First, try to find an unbuddied z3fold page. */ - unbuddied = this_cpu_ptr(pool->unbuddied); - for_each_unbuddied_list(i, chunks) { - struct list_head *l = &unbuddied[i]; - - zhdr = list_first_entry_or_null(READ_ONCE(l), - struct z3fold_header, buddy); - - if (!zhdr) - continue; - - /* Re-check under lock. */ - spin_lock(&pool->lock); - if (unlikely(zhdr != list_first_entry(READ_ONCE(l), - struct z3fold_header, buddy)) || - !z3fold_page_trylock(zhdr)) { - spin_unlock(&pool->lock); - zhdr = NULL; - migrate_enable(); - if (can_sleep) - cond_resched(); - goto lookup; - } - list_del_init(&zhdr->buddy); - zhdr->cpu = -1; - spin_unlock(&pool->lock); - - page = virt_to_page(zhdr); - if (test_bit(NEEDS_COMPACTING, &page->private) || - test_bit(PAGE_CLAIMED, &page->private)) { - z3fold_page_unlock(zhdr); - zhdr = NULL; - migrate_enable(); - if (can_sleep) - cond_resched(); - goto lookup; - } - - /* - * this page could not be removed from its unbuddied - * list while pool lock was held, and then we've taken - * page lock so kref_put could not be called before - * we got here, so it's safe to just call kref_get() - */ - kref_get(&zhdr->refcount); - break; - } - migrate_enable(); - - if (!zhdr) { - int cpu; - - /* look for _exact_ match on other cpus' lists */ - for_each_online_cpu(cpu) { - struct list_head *l; - - unbuddied = per_cpu_ptr(pool->unbuddied, cpu); - spin_lock(&pool->lock); - l = &unbuddied[chunks]; - - zhdr = list_first_entry_or_null(READ_ONCE(l), - struct z3fold_header, buddy); - - if (!zhdr || !z3fold_page_trylock(zhdr)) { - spin_unlock(&pool->lock); - zhdr = NULL; - continue; - } - list_del_init(&zhdr->buddy); - zhdr->cpu = -1; - spin_unlock(&pool->lock); - - page = virt_to_page(zhdr); - if (test_bit(NEEDS_COMPACTING, &page->private) || - test_bit(PAGE_CLAIMED, &page->private)) { - z3fold_page_unlock(zhdr); - zhdr = NULL; - if (can_sleep) - cond_resched(); - continue; - } - kref_get(&zhdr->refcount); - break; - } - } - - if (zhdr && !zhdr->slots) { - zhdr->slots = alloc_slots(pool, GFP_ATOMIC); - if (!zhdr->slots) - goto out_fail; - } - return zhdr; - -out_fail: - if (!put_z3fold_locked(zhdr)) { - add_to_unbuddied(pool, zhdr); - z3fold_page_unlock(zhdr); - } - return NULL; -} - -/* - * API Functions - */ - -/** - * z3fold_create_pool() - create a new z3fold pool - * @name: pool name - * @gfp: gfp flags when allocating the z3fold pool structure - * - * Return: pointer to the new z3fold pool or NULL if the metadata allocation - * failed. - */ -static struct z3fold_pool *z3fold_create_pool(const char *name, gfp_t gfp) -{ - struct z3fold_pool *pool = NULL; - int i, cpu; - - pool = kzalloc(sizeof(struct z3fold_pool), gfp); - if (!pool) - goto out; - pool->c_handle = kmem_cache_create("z3fold_handle", - sizeof(struct z3fold_buddy_slots), - SLOTS_ALIGN, 0, NULL); - if (!pool->c_handle) - goto out_c; - spin_lock_init(&pool->lock); - spin_lock_init(&pool->stale_lock); - pool->unbuddied = __alloc_percpu(sizeof(struct list_head) * NCHUNKS, - __alignof__(struct list_head)); - if (!pool->unbuddied) - goto out_pool; - for_each_possible_cpu(cpu) { - struct list_head *unbuddied = - per_cpu_ptr(pool->unbuddied, cpu); - for_each_unbuddied_list(i, 0) - INIT_LIST_HEAD(&unbuddied[i]); - } - INIT_LIST_HEAD(&pool->stale); - atomic64_set(&pool->pages_nr, 0); - pool->name = name; - pool->compact_wq = create_singlethread_workqueue(pool->name); - if (!pool->compact_wq) - goto out_unbuddied; - pool->release_wq = create_singlethread_workqueue(pool->name); - if (!pool->release_wq) - goto out_wq; - INIT_WORK(&pool->work, free_pages_work); - return pool; - -out_wq: - destroy_workqueue(pool->compact_wq); -out_unbuddied: - free_percpu(pool->unbuddied); -out_pool: - kmem_cache_destroy(pool->c_handle); -out_c: - kfree(pool); -out: - return NULL; -} - -/** - * z3fold_destroy_pool() - destroys an existing z3fold pool - * @pool: the z3fold pool to be destroyed - * - * The pool should be emptied before this function is called. - */ -static void z3fold_destroy_pool(struct z3fold_pool *pool) -{ - kmem_cache_destroy(pool->c_handle); - - /* - * We need to destroy pool->compact_wq before pool->release_wq, - * as any pending work on pool->compact_wq will call - * queue_work(pool->release_wq, &pool->work). - * - * There are still outstanding pages until both workqueues are drained, - * so we cannot unregister migration until then. - */ - - destroy_workqueue(pool->compact_wq); - destroy_workqueue(pool->release_wq); - free_percpu(pool->unbuddied); - kfree(pool); -} - -static const struct movable_operations z3fold_mops; - -/** - * z3fold_alloc() - allocates a region of a given size - * @pool: z3fold pool from which to allocate - * @size: size in bytes of the desired allocation - * @gfp: gfp flags used if the pool needs to grow - * @handle: handle of the new allocation - * - * This function will attempt to find a free region in the pool large enough to - * satisfy the allocation request. A search of the unbuddied lists is - * performed first. If no suitable free region is found, then a new page is - * allocated and added to the pool to satisfy the request. - * - * Return: 0 if success and handle is set, otherwise -EINVAL if the size or - * gfp arguments are invalid or -ENOMEM if the pool was unable to allocate - * a new page. - */ -static int z3fold_alloc(struct z3fold_pool *pool, size_t size, gfp_t gfp, - unsigned long *handle) -{ - int chunks = size_to_chunks(size); - struct z3fold_header *zhdr = NULL; - struct page *page = NULL; - enum buddy bud; - bool can_sleep = gfpflags_allow_blocking(gfp); - - if (!size || (gfp & __GFP_HIGHMEM)) - return -EINVAL; - - if (size > PAGE_SIZE) - return -ENOSPC; - - if (size > PAGE_SIZE - ZHDR_SIZE_ALIGNED - CHUNK_SIZE) - bud = HEADLESS; - else { -retry: - zhdr = __z3fold_alloc(pool, size, can_sleep); - if (zhdr) { - bud = get_free_buddy(zhdr, chunks); - if (bud == HEADLESS) { - if (!put_z3fold_locked(zhdr)) - z3fold_page_unlock(zhdr); - pr_err("No free chunks in unbuddied\n"); - WARN_ON(1); - goto retry; - } - page = virt_to_page(zhdr); - goto found; - } - bud = FIRST; - } - - page = alloc_page(gfp); - if (!page) - return -ENOMEM; - - zhdr = init_z3fold_page(page, bud == HEADLESS, pool, gfp); - if (!zhdr) { - __free_page(page); - return -ENOMEM; - } - atomic64_inc(&pool->pages_nr); - - if (bud == HEADLESS) { - set_bit(PAGE_HEADLESS, &page->private); - goto headless; - } - if (can_sleep) { - lock_page(page); - __SetPageMovable(page, &z3fold_mops); - unlock_page(page); - } else { - WARN_ON(!trylock_page(page)); - __SetPageMovable(page, &z3fold_mops); - unlock_page(page); - } - z3fold_page_lock(zhdr); - -found: - if (bud == FIRST) - zhdr->first_chunks = chunks; - else if (bud == LAST) - zhdr->last_chunks = chunks; - else { - zhdr->middle_chunks = chunks; - zhdr->start_middle = zhdr->first_chunks + ZHDR_CHUNKS; - } - add_to_unbuddied(pool, zhdr); - -headless: - spin_lock(&pool->lock); - *handle = encode_handle(zhdr, bud); - spin_unlock(&pool->lock); - if (bud != HEADLESS) - z3fold_page_unlock(zhdr); - - return 0; -} - -/** - * z3fold_free() - frees the allocation associated with the given handle - * @pool: pool in which the allocation resided - * @handle: handle associated with the allocation returned by z3fold_alloc() - * - * In the case that the z3fold page in which the allocation resides is under - * reclaim, as indicated by the PAGE_CLAIMED flag being set, this function - * only sets the first|middle|last_chunks to 0. The page is actually freed - * once all buddies are evicted (see z3fold_reclaim_page() below). - */ -static void z3fold_free(struct z3fold_pool *pool, unsigned long handle) -{ - struct z3fold_header *zhdr; - struct page *page; - enum buddy bud; - bool page_claimed; - - zhdr = get_z3fold_header(handle); - page = virt_to_page(zhdr); - page_claimed = test_and_set_bit(PAGE_CLAIMED, &page->private); - - if (test_bit(PAGE_HEADLESS, &page->private)) { - /* if a headless page is under reclaim, just leave. - * NB: we use test_and_set_bit for a reason: if the bit - * has not been set before, we release this page - * immediately so we don't care about its value any more. - */ - if (!page_claimed) { - put_z3fold_header(zhdr); - free_z3fold_page(page, true); - atomic64_dec(&pool->pages_nr); - } - return; - } - - /* Non-headless case */ - bud = handle_to_buddy(handle); - - switch (bud) { - case FIRST: - zhdr->first_chunks = 0; - break; - case MIDDLE: - zhdr->middle_chunks = 0; - break; - case LAST: - zhdr->last_chunks = 0; - break; - default: - pr_err("%s: unknown bud %d\n", __func__, bud); - WARN_ON(1); - put_z3fold_header(zhdr); - return; - } - - if (!page_claimed) - free_handle(handle, zhdr); - if (put_z3fold_locked_list(zhdr)) - return; - if (page_claimed) { - /* the page has not been claimed by us */ - put_z3fold_header(zhdr); - return; - } - if (test_and_set_bit(NEEDS_COMPACTING, &page->private)) { - clear_bit(PAGE_CLAIMED, &page->private); - put_z3fold_header(zhdr); - return; - } - if (zhdr->cpu < 0 || !cpu_online(zhdr->cpu)) { - zhdr->cpu = -1; - kref_get(&zhdr->refcount); - clear_bit(PAGE_CLAIMED, &page->private); - do_compact_page(zhdr, true); - return; - } - kref_get(&zhdr->refcount); - clear_bit(PAGE_CLAIMED, &page->private); - queue_work_on(zhdr->cpu, pool->compact_wq, &zhdr->work); - put_z3fold_header(zhdr); -} - -/** - * z3fold_map() - maps the allocation associated with the given handle - * @pool: pool in which the allocation resides - * @handle: handle associated with the allocation to be mapped - * - * Extracts the buddy number from handle and constructs the pointer to the - * correct starting chunk within the page. - * - * Returns: a pointer to the mapped allocation - */ -static void *z3fold_map(struct z3fold_pool *pool, unsigned long handle) -{ - struct z3fold_header *zhdr; - struct page *page; - void *addr; - enum buddy buddy; - - zhdr = get_z3fold_header(handle); - addr = zhdr; - page = virt_to_page(zhdr); - - if (test_bit(PAGE_HEADLESS, &page->private)) - goto out; - - buddy = handle_to_buddy(handle); - switch (buddy) { - case FIRST: - addr += ZHDR_SIZE_ALIGNED; - break; - case MIDDLE: - addr += zhdr->start_middle << CHUNK_SHIFT; - set_bit(MIDDLE_CHUNK_MAPPED, &page->private); - break; - case LAST: - addr += PAGE_SIZE - (handle_to_chunks(handle) << CHUNK_SHIFT); - break; - default: - pr_err("unknown buddy id %d\n", buddy); - WARN_ON(1); - addr = NULL; - break; - } - - if (addr) - zhdr->mapped_count++; -out: - put_z3fold_header(zhdr); - return addr; -} - -/** - * z3fold_unmap() - unmaps the allocation associated with the given handle - * @pool: pool in which the allocation resides - * @handle: handle associated with the allocation to be unmapped - */ -static void z3fold_unmap(struct z3fold_pool *pool, unsigned long handle) -{ - struct z3fold_header *zhdr; - struct page *page; - enum buddy buddy; - - zhdr = get_z3fold_header(handle); - page = virt_to_page(zhdr); - - if (test_bit(PAGE_HEADLESS, &page->private)) - return; - - buddy = handle_to_buddy(handle); - if (buddy == MIDDLE) - clear_bit(MIDDLE_CHUNK_MAPPED, &page->private); - zhdr->mapped_count--; - put_z3fold_header(zhdr); -} - -/** - * z3fold_get_pool_pages() - gets the z3fold pool size in pages - * @pool: pool whose size is being queried - * - * Returns: size in pages of the given pool. - */ -static u64 z3fold_get_pool_pages(struct z3fold_pool *pool) -{ - return atomic64_read(&pool->pages_nr); -} - -static bool z3fold_page_isolate(struct page *page, isolate_mode_t mode) -{ - struct z3fold_header *zhdr; - struct z3fold_pool *pool; - - VM_BUG_ON_PAGE(PageIsolated(page), page); - - if (test_bit(PAGE_HEADLESS, &page->private)) - return false; - - zhdr = page_address(page); - z3fold_page_lock(zhdr); - if (test_bit(NEEDS_COMPACTING, &page->private) || - test_bit(PAGE_STALE, &page->private)) - goto out; - - if (zhdr->mapped_count != 0 || zhdr->foreign_handles != 0) - goto out; - - if (test_and_set_bit(PAGE_CLAIMED, &page->private)) - goto out; - pool = zhdr_to_pool(zhdr); - spin_lock(&pool->lock); - if (!list_empty(&zhdr->buddy)) - list_del_init(&zhdr->buddy); - spin_unlock(&pool->lock); - - kref_get(&zhdr->refcount); - z3fold_page_unlock(zhdr); - return true; - -out: - z3fold_page_unlock(zhdr); - return false; -} - -static int z3fold_page_migrate(struct page *newpage, struct page *page, - enum migrate_mode mode) -{ - struct z3fold_header *zhdr, *new_zhdr; - struct z3fold_pool *pool; - - VM_BUG_ON_PAGE(!PageIsolated(page), page); - VM_BUG_ON_PAGE(!test_bit(PAGE_CLAIMED, &page->private), page); - VM_BUG_ON_PAGE(!PageLocked(newpage), newpage); - - zhdr = page_address(page); - pool = zhdr_to_pool(zhdr); - - if (!z3fold_page_trylock(zhdr)) - return -EAGAIN; - if (zhdr->mapped_count != 0 || zhdr->foreign_handles != 0) { - clear_bit(PAGE_CLAIMED, &page->private); - z3fold_page_unlock(zhdr); - return -EBUSY; - } - if (work_pending(&zhdr->work)) { - z3fold_page_unlock(zhdr); - return -EAGAIN; - } - new_zhdr = page_address(newpage); - memcpy(new_zhdr, zhdr, PAGE_SIZE); - newpage->private = page->private; - set_bit(PAGE_MIGRATED, &page->private); - z3fold_page_unlock(zhdr); - spin_lock_init(&new_zhdr->page_lock); - INIT_WORK(&new_zhdr->work, compact_page_work); - /* - * z3fold_page_isolate() ensures that new_zhdr->buddy is empty, - * so we only have to reinitialize it. - */ - INIT_LIST_HEAD(&new_zhdr->buddy); - __ClearPageMovable(page); - - get_page(newpage); - z3fold_page_lock(new_zhdr); - if (new_zhdr->first_chunks) - encode_handle(new_zhdr, FIRST); - if (new_zhdr->last_chunks) - encode_handle(new_zhdr, LAST); - if (new_zhdr->middle_chunks) - encode_handle(new_zhdr, MIDDLE); - set_bit(NEEDS_COMPACTING, &newpage->private); - new_zhdr->cpu = smp_processor_id(); - __SetPageMovable(newpage, &z3fold_mops); - z3fold_page_unlock(new_zhdr); - - queue_work_on(new_zhdr->cpu, pool->compact_wq, &new_zhdr->work); - - /* PAGE_CLAIMED and PAGE_MIGRATED are cleared now. */ - page->private = 0; - put_page(page); - return 0; -} - -static void z3fold_page_putback(struct page *page) -{ - struct z3fold_header *zhdr; - struct z3fold_pool *pool; - - zhdr = page_address(page); - pool = zhdr_to_pool(zhdr); - - z3fold_page_lock(zhdr); - if (!list_empty(&zhdr->buddy)) - list_del_init(&zhdr->buddy); - INIT_LIST_HEAD(&page->lru); - if (put_z3fold_locked(zhdr)) - return; - if (list_empty(&zhdr->buddy)) - add_to_unbuddied(pool, zhdr); - clear_bit(PAGE_CLAIMED, &page->private); - z3fold_page_unlock(zhdr); -} - -static const struct movable_operations z3fold_mops = { - .isolate_page = z3fold_page_isolate, - .migrate_page = z3fold_page_migrate, - .putback_page = z3fold_page_putback, -}; - -/***************** - * zpool - ****************/ - -static void *z3fold_zpool_create(const char *name, gfp_t gfp) -{ - return z3fold_create_pool(name, gfp); -} - -static void z3fold_zpool_destroy(void *pool) -{ - z3fold_destroy_pool(pool); -} - -static int z3fold_zpool_malloc(void *pool, size_t size, gfp_t gfp, - unsigned long *handle) -{ - return z3fold_alloc(pool, size, gfp, handle); -} -static void z3fold_zpool_free(void *pool, unsigned long handle) -{ - z3fold_free(pool, handle); -} - -static void *z3fold_zpool_map(void *pool, unsigned long handle, - enum zpool_mapmode mm) -{ - return z3fold_map(pool, handle); -} -static void z3fold_zpool_unmap(void *pool, unsigned long handle) -{ - z3fold_unmap(pool, handle); -} - -static u64 z3fold_zpool_total_pages(void *pool) -{ - return z3fold_get_pool_pages(pool); -} - -static struct zpool_driver z3fold_zpool_driver = { - .type = "z3fold", - .sleep_mapped = true, - .owner = THIS_MODULE, - .create = z3fold_zpool_create, - .destroy = z3fold_zpool_destroy, - .malloc = z3fold_zpool_malloc, - .free = z3fold_zpool_free, - .map = z3fold_zpool_map, - .unmap = z3fold_zpool_unmap, - .total_pages = z3fold_zpool_total_pages, -}; - -MODULE_ALIAS("zpool-z3fold"); - -static int __init init_z3fold(void) -{ - /* - * Make sure the z3fold header is not larger than the page size and - * there has remaining spaces for its buddy. - */ - BUILD_BUG_ON(ZHDR_SIZE_ALIGNED > PAGE_SIZE - CHUNK_SIZE); - zpool_register_driver(&z3fold_zpool_driver); - - return 0; -} - -static void __exit exit_z3fold(void) -{ - zpool_unregister_driver(&z3fold_zpool_driver); -} - -module_init(init_z3fold); -module_exit(exit_z3fold); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Vitaly Wool "); -MODULE_DESCRIPTION("3-Fold Allocator for Compressed Pages");