From patchwork Thu May 12 15:41:02 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A . Shutemov" X-Patchwork-Id: 9083361 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id CE76CBF29F for ; Thu, 12 May 2016 15:43:14 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9824820212 for ; Thu, 12 May 2016 15:43:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C5BF200E7 for ; Thu, 12 May 2016 15:43:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932697AbcELPmw (ORCPT ); Thu, 12 May 2016 11:42:52 -0400 Received: from mga09.intel.com ([134.134.136.24]:20424 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932641AbcELPlz (ORCPT ); Thu, 12 May 2016 11:41:55 -0400 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP; 12 May 2016 08:41:36 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,610,1455004800"; d="scan'208";a="951887629" Received: from black.fi.intel.com ([10.237.72.93]) by orsmga001.jf.intel.com with ESMTP; 12 May 2016 08:41:31 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 259C710D9; Thu, 12 May 2016 18:41:21 +0300 (EEST) From: "Kirill A. Shutemov" To: Hugh Dickins , Andrea Arcangeli , Andrew Morton Cc: Dave Hansen , Vlastimil Babka , Christoph Lameter , Naoya Horiguchi , Jerome Marchand , Yang Shi , Sasha Levin , Andres Lagar-Cavilla , Ning Qu , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv8 22/32] shmem: prepare huge= mount option and sysfs knob Date: Thu, 12 May 2016 18:41:02 +0300 Message-Id: <1463067672-134698-23-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1463067672-134698-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1463067672-134698-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-8.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds new mount option "huge=". It can have following values: - "always": Attempt to allocate huge pages every time we need a new page; - "never": Do not allocate huge pages; - "within_size": Only allocate huge page if it will be fully within i_size. Also respect fadvise()/madvise() hints; - "advise: Only allocate huge pages if requested with fadvise()/madvise(); Default is "never" for now. "mount -o remount,huge= /mountpoint" works fine after mount: remounting huge=never will not attempt to break up huge pages at all, just stop more from being allocated. No new config option: put this under CONFIG_TRANSPARENT_HUGEPAGE, which is the appropriate option to protect those who don't want the new bloat, and with which we shall share some pmd code. Prohibit the option when !CONFIG_TRANSPARENT_HUGEPAGE, just as mpol is invalid without CONFIG_NUMA (was hidden in mpol_parse_str(): make it explicit). Allow enabling THP only if the machine has_transparent_hugepage(). But what about Shmem with no user-visible mount? SysV SHM, memfds, shared anonymous mmaps (of /dev/zero or MAP_ANONYMOUS), GPU drivers' DRM objects, Ashmem. Though unlikely to suit all usages, provide sysfs knob /sys/kernel/mm/transparent_hugepage/shmem_enabled to experiment with huge on those. And allow shmem_enabled two further values: - "deny": For use in emergencies, to force the huge option off from all mounts; - "force": Force the huge option on for all - very useful for testing; Based on patch by Hugh Dickins. Signed-off-by: Kirill A. Shutemov --- include/linux/huge_mm.h | 2 + include/linux/shmem_fs.h | 3 +- mm/huge_memory.c | 3 + mm/shmem.c | 161 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 168 insertions(+), 1 deletion(-) diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 95f83770443c..278ade85e224 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -41,6 +41,8 @@ enum transparent_hugepage_flag { #endif }; +extern struct kobj_attribute shmem_enabled_attr; + #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) #define HPAGE_PMD_NR (1<gid = make_kgid(current_user_ns(), gid); if (!gid_valid(sbinfo->gid)) goto bad_val; +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + } else if (!strcmp(this_char, "huge")) { + int huge; + huge = shmem_parse_huge(value); + if (huge < 0) + goto bad_val; + if (!has_transparent_hugepage() && + huge != SHMEM_HUGE_NEVER) + goto bad_val; + sbinfo->huge = huge; +#endif +#ifdef CONFIG_NUMA } else if (!strcmp(this_char,"mpol")) { mpol_put(mpol); mpol = NULL; if (mpol_parse_str(value, &mpol)) goto bad_val; +#endif } else { pr_err("tmpfs: Bad mount option %s\n", this_char); goto error; @@ -2907,6 +3001,7 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data) goto out; error = 0; + sbinfo->huge = config.huge; sbinfo->max_blocks = config.max_blocks; sbinfo->max_inodes = config.max_inodes; sbinfo->free_inodes = config.max_inodes - inodes; @@ -2940,6 +3035,11 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root) if (!gid_eq(sbinfo->gid, GLOBAL_ROOT_GID)) seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbinfo->gid)); +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + /* Rightly or wrongly, show huge mount option unmasked by shmem_huge */ + if (sbinfo->huge) + seq_printf(seq, ",huge=%s", shmem_format_huge(sbinfo->huge)); +#endif shmem_show_mpol(seq, sbinfo->mpol); return 0; } @@ -3278,6 +3378,13 @@ int __init shmem_init(void) pr_err("Could not kern_mount tmpfs\n"); goto out1; } + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (has_transparent_hugepage() && shmem_huge < SHMEM_HUGE_DENY) + SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge; + else + shmem_huge = 0; /* just in case it was patched */ +#endif return 0; out1: @@ -3289,6 +3396,60 @@ out3: return error; } +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && defined(CONFIG_SYSFS) +static ssize_t shmem_enabled_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + int values[] = { + SHMEM_HUGE_ALWAYS, + SHMEM_HUGE_WITHIN_SIZE, + SHMEM_HUGE_ADVISE, + SHMEM_HUGE_NEVER, + SHMEM_HUGE_DENY, + SHMEM_HUGE_FORCE, + }; + int i, count; + + for (i = 0, count = 0; i < ARRAY_SIZE(values); i++) { + const char *fmt = shmem_huge == values[i] ? "[%s] " : "%s "; + + count += sprintf(buf + count, fmt, + shmem_format_huge(values[i])); + } + buf[count - 1] = '\n'; + return count; +} + +static ssize_t shmem_enabled_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + char tmp[16]; + int huge; + + if (count + 1 > sizeof(tmp)) + return -EINVAL; + memcpy(tmp, buf, count); + tmp[count] = '\0'; + if (count && tmp[count - 1] == '\n') + tmp[count - 1] = '\0'; + + huge = shmem_parse_huge(tmp); + if (huge == -EINVAL) + return -EINVAL; + if (!has_transparent_hugepage() && + huge != SHMEM_HUGE_NEVER && huge != SHMEM_HUGE_DENY) + return -EINVAL; + + shmem_huge = huge; + if (shmem_huge < SHMEM_HUGE_DENY) + SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge; + return count; +} + +struct kobj_attribute shmem_enabled_attr = + __ATTR(shmem_enabled, 0644, shmem_enabled_show, shmem_enabled_store); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE && CONFIG_SYSFS */ + #else /* !CONFIG_SHMEM */ /*