From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54384C46460 for ; Mon, 20 May 2019 03:53:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A80D20856 for ; Mon, 20 May 2019 03:53:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558324405; bh=Lhoj44BvwCBT7Vq/+HvISGR7LjJbw/9Kq0Vm/LmiWTw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=OmVRIqWIW3e6xZelq2U6mqJn0jyGmJvQA5X5fmS4d454JXF4LTmQPYoMq+DE7H6W9 s3otzOjlav5Xu7Udz1M7h2AnZn0Yw/e80eDg8jCsM+81uuBQ0y1GJH6e4Lr5wNksPD 2zCDYAMYrYCZptLywITZrcIkq+qPepzjrU4LAM4s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730308AbfETDxX (ORCPT ); Sun, 19 May 2019 23:53:23 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:43846 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726052AbfETDxX (ORCPT ); Sun, 19 May 2019 23:53:23 -0400 Received: by mail-pg1-f196.google.com with SMTP id t22so6070042pgi.10 for ; Sun, 19 May 2019 20:53:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=89p7CoU4S9UFAIEQ4qQeLvyukcRmWZty6wgd/XamBhs=; b=Caux5HDngteXa5fZ7XLnDhpQOpZUHg9z6OGEBD9kplxhqTCkOkn0nPKyDUnZvR7BEZ hmroxWZ/B5nvgDPgtZNqJsSKb9b48wpHzo1a47mUlARGD2Jq4O84JWPUNl0x8PEJR+XV 8BtzmWqjjyfomQd+a360QgYlvk6RLWze4t749nG67Rk4F65CS66g/47rULD44Uf+xKIl yoFtR9BmF8S2IJxiXuzRUxDzPObzJ+fjAJZSKvoLXNHnVgNVbLwHjr9jOWUkcA/fm6GD zdoHvjTRxs+QnEL/Ly5U+ix/mbq4UGyaHh0a9JDcAaojR+ydrDC6a853uXcm9G0k69il R1WQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=89p7CoU4S9UFAIEQ4qQeLvyukcRmWZty6wgd/XamBhs=; b=GPShbnt3vef6VB2qxFMbTAomwBOSS97EIz4lHY04trWyeO7YpmKO8d1ZCadoUwGgEZ HF0W2i9X8etuH7kZd4RML3D+bO3xJx2lXk3NVQKRIhzT+Go+6RaUfgHnb7wyY5JmiOA2 f1cRPVWZJNAZiCpXU96mPw3mRPJni8ZZToRlbj3z+HBvbHunO6RYhAJ1tjhTQuPEJ7lI ScZUdc7a27KaLlasPjmNelEPBbzs2VDIHgasVE8FW7XaVLW1PvjrBfemqPmtFVD+DiOJ YToJ4kg5xpfli5GWoc3egRBwIxxBT1zkIG9gnTE0xD55hw4vuUf989OuqlXqLJGxpwKb ny4A== X-Gm-Message-State: APjAAAWziwlLubx/5oMURBiEx8e5BSino1Af+Jh8UDsGv3XVHhuMgnoG b93no+PNk+dn92eWtnexIHk= X-Google-Smtp-Source: APXvYqxd8/hhxsSgSvvNWTVzT+1zlZvV711Jl/ozMiRJDFxhSFYMXe5yIGw6TiA9hGerZo479aN1pg== X-Received: by 2002:a62:82c1:: with SMTP id w184mr47287418pfd.171.1558324402213; Sun, 19 May 2019 20:53:22 -0700 (PDT) Received: from bbox-2.seo.corp.google.com ([2401:fa00:d:0:98f1:8b3d:1f37:3e8]) by smtp.gmail.com with ESMTPSA id x66sm3312779pfx.139.2019.05.19.20.53.17 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 19 May 2019 20:53:21 -0700 (PDT) From: Minchan Kim To: Andrew Morton Cc: LKML , linux-mm , Michal Hocko , Johannes Weiner , Tim Murray , Joel Fernandes , Suren Baghdasaryan , Daniel Colascione , Shakeel Butt , Sonny Rao , Brian Geffon , Minchan Kim Subject: [RFC 4/7] mm: factor out madvise's core functionality Date: Mon, 20 May 2019 12:52:51 +0900 Message-Id: <20190520035254.57579-5-minchan@kernel.org> X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog In-Reply-To: <20190520035254.57579-1-minchan@kernel.org> References: <20190520035254.57579-1-minchan@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch factor out madvise's core functionality so that upcoming patch can reuse it without duplication. It shouldn't change any behavior. Signed-off-by: Minchan Kim --- mm/madvise.c | 168 +++++++++++++++++++++++++++------------------------ 1 file changed, 89 insertions(+), 79 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index 9a6698b56845..119e82e1f065 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -742,7 +742,8 @@ static long madvise_dontneed_single_vma(struct vm_area_struct *vma, return 0; } -static long madvise_dontneed_free(struct vm_area_struct *vma, +static long madvise_dontneed_free(struct task_struct *tsk, + struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end, int behavior) @@ -754,8 +755,8 @@ static long madvise_dontneed_free(struct vm_area_struct *vma, if (!userfaultfd_remove(vma, start, end)) { *prev = NULL; /* mmap_sem has been dropped, prev is stale */ - down_read(¤t->mm->mmap_sem); - vma = find_vma(current->mm, start); + down_read(&tsk->mm->mmap_sem); + vma = find_vma(tsk->mm, start); if (!vma) return -ENOMEM; if (start < vma->vm_start) { @@ -802,7 +803,8 @@ static long madvise_dontneed_free(struct vm_area_struct *vma, * Application wants to free up the pages and associated backing store. * This is effectively punching a hole into the middle of a file. */ -static long madvise_remove(struct vm_area_struct *vma, +static long madvise_remove(struct task_struct *tsk, + struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end) { @@ -836,13 +838,13 @@ static long madvise_remove(struct vm_area_struct *vma, get_file(f); if (userfaultfd_remove(vma, start, end)) { /* mmap_sem was not released by userfaultfd_remove() */ - up_read(¤t->mm->mmap_sem); + up_read(&tsk->mm->mmap_sem); } error = vfs_fallocate(f, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, offset, end - start); fput(f); - down_read(¤t->mm->mmap_sem); + down_read(&tsk->mm->mmap_sem); return error; } @@ -916,12 +918,13 @@ static int madvise_inject_error(int behavior, #endif static long -madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, - unsigned long start, unsigned long end, int behavior) +madvise_vma(struct task_struct *tsk, struct vm_area_struct *vma, + struct vm_area_struct **prev, unsigned long start, + unsigned long end, int behavior) { switch (behavior) { case MADV_REMOVE: - return madvise_remove(vma, prev, start, end); + return madvise_remove(tsk, vma, prev, start, end); case MADV_WILLNEED: return madvise_willneed(vma, prev, start, end); case MADV_COOL: @@ -930,7 +933,8 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, return madvise_cold(vma, start, end); case MADV_FREE: case MADV_DONTNEED: - return madvise_dontneed_free(vma, prev, start, end, behavior); + return madvise_dontneed_free(tsk, vma, prev, start, + end, behavior); default: return madvise_behavior(vma, prev, start, end, behavior); } @@ -974,68 +978,8 @@ madvise_behavior_valid(int behavior) } } -/* - * The madvise(2) system call. - * - * Applications can use madvise() to advise the kernel how it should - * handle paging I/O in this VM area. The idea is to help the kernel - * use appropriate read-ahead and caching techniques. The information - * provided is advisory only, and can be safely disregarded by the - * kernel without affecting the correct operation of the application. - * - * behavior values: - * MADV_NORMAL - the default behavior is to read clusters. This - * results in some read-ahead and read-behind. - * MADV_RANDOM - the system should read the minimum amount of data - * on any access, since it is unlikely that the appli- - * cation will need more than what it asks for. - * MADV_SEQUENTIAL - pages in the given range will probably be accessed - * once, so they can be aggressively read ahead, and - * can be freed soon after they are accessed. - * MADV_WILLNEED - the application is notifying the system to read - * some pages ahead. - * MADV_DONTNEED - the application is finished with the given range, - * so the kernel can free resources associated with it. - * MADV_FREE - the application marks pages in the given range as lazy free, - * where actual purges are postponed until memory pressure happens. - * MADV_REMOVE - the application wants to free up the given range of - * pages and associated backing store. - * MADV_DONTFORK - omit this area from child's address space when forking: - * typically, to avoid COWing pages pinned by get_user_pages(). - * MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking. - * MADV_WIPEONFORK - present the child process with zero-filled memory in this - * range after a fork. - * MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK - * MADV_HWPOISON - trigger memory error handler as if the given memory range - * were corrupted by unrecoverable hardware memory failure. - * MADV_SOFT_OFFLINE - try to soft-offline the given range of memory. - * MADV_MERGEABLE - the application recommends that KSM try to merge pages in - * this area with pages of identical content from other such areas. - * MADV_UNMERGEABLE- cancel MADV_MERGEABLE: no longer merge pages with others. - * MADV_HUGEPAGE - the application wants to back the given range by transparent - * huge pages in the future. Existing pages might be coalesced and - * new pages might be allocated as THP. - * MADV_NOHUGEPAGE - mark the given range as not worth being backed by - * transparent huge pages so the existing pages will not be - * coalesced into THP and new pages will not be allocated as THP. - * MADV_DONTDUMP - the application wants to prevent pages in the given range - * from being included in its core dump. - * MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump. - * - * return values: - * zero - success - * -EINVAL - start + len < 0, start is not page-aligned, - * "behavior" is not a valid value, or application - * is attempting to release locked or shared pages, - * or the specified address range includes file, Huge TLB, - * MAP_SHARED or VMPFNMAP range. - * -ENOMEM - addresses in the specified range are not currently - * mapped, or are outside the AS of the process. - * -EIO - an I/O error occurred while paging in data. - * -EBADF - map exists, but area maps something that isn't a file. - * -EAGAIN - a kernel resource was temporarily unavailable. - */ -SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) +static int madvise_core(struct task_struct *tsk, unsigned long start, + size_t len_in, int behavior) { unsigned long end, tmp; struct vm_area_struct *vma, *prev; @@ -1071,10 +1015,10 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) write = madvise_need_mmap_write(behavior); if (write) { - if (down_write_killable(¤t->mm->mmap_sem)) + if (down_write_killable(&tsk->mm->mmap_sem)) return -EINTR; } else { - down_read(¤t->mm->mmap_sem); + down_read(&tsk->mm->mmap_sem); } /* @@ -1082,7 +1026,7 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) * ranges, just ignore them, but return -ENOMEM at the end. * - different from the way of handling in mlock etc. */ - vma = find_vma_prev(current->mm, start, &prev); + vma = find_vma_prev(tsk->mm, start, &prev); if (vma && start > vma->vm_start) prev = vma; @@ -1107,7 +1051,7 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) tmp = end; /* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */ - error = madvise_vma(vma, &prev, start, tmp, behavior); + error = madvise_vma(tsk, vma, &prev, start, tmp, behavior); if (error) goto out; start = tmp; @@ -1119,14 +1063,80 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) if (prev) vma = prev->vm_next; else /* madvise_remove dropped mmap_sem */ - vma = find_vma(current->mm, start); + vma = find_vma(tsk->mm, start); } out: blk_finish_plug(&plug); if (write) - up_write(¤t->mm->mmap_sem); + up_write(&tsk->mm->mmap_sem); else - up_read(¤t->mm->mmap_sem); + up_read(&tsk->mm->mmap_sem); return error; } + +/* + * The madvise(2) system call. + * + * Applications can use madvise() to advise the kernel how it should + * handle paging I/O in this VM area. The idea is to help the kernel + * use appropriate read-ahead and caching techniques. The information + * provided is advisory only, and can be safely disregarded by the + * kernel without affecting the correct operation of the application. + * + * behavior values: + * MADV_NORMAL - the default behavior is to read clusters. This + * results in some read-ahead and read-behind. + * MADV_RANDOM - the system should read the minimum amount of data + * on any access, since it is unlikely that the appli- + * cation will need more than what it asks for. + * MADV_SEQUENTIAL - pages in the given range will probably be accessed + * once, so they can be aggressively read ahead, and + * can be freed soon after they are accessed. + * MADV_WILLNEED - the application is notifying the system to read + * some pages ahead. + * MADV_DONTNEED - the application is finished with the given range, + * so the kernel can free resources associated with it. + * MADV_FREE - the application marks pages in the given range as lazy free, + * where actual purges are postponed until memory pressure happens. + * MADV_REMOVE - the application wants to free up the given range of + * pages and associated backing store. + * MADV_DONTFORK - omit this area from child's address space when forking: + * typically, to avoid COWing pages pinned by get_user_pages(). + * MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking. + * MADV_WIPEONFORK - present the child process with zero-filled memory in this + * range after a fork. + * MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK + * MADV_HWPOISON - trigger memory error handler as if the given memory range + * were corrupted by unrecoverable hardware memory failure. + * MADV_SOFT_OFFLINE - try to soft-offline the given range of memory. + * MADV_MERGEABLE - the application recommends that KSM try to merge pages in + * this area with pages of identical content from other such areas. + * MADV_UNMERGEABLE- cancel MADV_MERGEABLE: no longer merge pages with others. + * MADV_HUGEPAGE - the application wants to back the given range by transparent + * huge pages in the future. Existing pages might be coalesced and + * new pages might be allocated as THP. + * MADV_NOHUGEPAGE - mark the given range as not worth being backed by + * transparent huge pages so the existing pages will not be + * coalesced into THP and new pages will not be allocated as THP. + * MADV_DONTDUMP - the application wants to prevent pages in the given range + * from being included in its core dump. + * MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump. + * + * return values: + * zero - success + * -EINVAL - start + len < 0, start is not page-aligned, + * "behavior" is not a valid value, or application + * is attempting to release locked or shared pages, + * or the specified address range includes file, Huge TLB, + * MAP_SHARED or VMPFNMAP range. + * -ENOMEM - addresses in the specified range are not currently + * mapped, or are outside the AS of the process. + * -EIO - an I/O error occurred while paging in data. + * -EBADF - map exists, but area maps something that isn't a file. + * -EAGAIN - a kernel resource was temporarily unavailable. + */ +SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) +{ + return madvise_core(current, start, len_in, behavior); +} -- 2.21.0.1020.gf2820cf01a-goog