From patchwork Thu Aug 8 23:13:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 11084959 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EE6241709 for ; Thu, 8 Aug 2019 23:14:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DB3A128826 for ; Thu, 8 Aug 2019 23:14:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CEEA128AFF; Thu, 8 Aug 2019 23:14:07 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 41C7628AFF for ; Thu, 8 Aug 2019 23:14:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732796AbfHHXOF (ORCPT ); Thu, 8 Aug 2019 19:14:05 -0400 Received: from mail-vs1-f74.google.com ([209.85.217.74]:42672 "EHLO mail-vs1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404667AbfHHXOF (ORCPT ); Thu, 8 Aug 2019 19:14:05 -0400 Received: by mail-vs1-f74.google.com with SMTP id a11so24688630vso.9 for ; Thu, 08 Aug 2019 16:14:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=M6cyBd5hA6OsVmAelGzV5tX+uF9n4OBWzNC5c9d9ybI=; b=r1KEmh0qrOpvBm1/+0oF0sFMH6EQNPOKTvWW1271fb2M52m+iVMsdTPIGKzfVVpgj5 x+Nc7IcNm8URXfh6TYEay9WEJj4RCDbRjTAMgdrTcpePccY/hODxMK3rNh/znjoVcOBh LHTQpfT5/V4EZ7R6N+KMldgXBUoH0DykmWZx9LJEzyLnRFCME7SC3gsq4nP41UK1D3az fXXxpAnfQK8rjWMgzEd+dqkIbR5A5/BX9N3Fv+dnJlUU3lDtlUjaBsCblfohOv1PHDlw HoFX3WEegCMRRcW1gySNo8nwEMo4BRcSGuyQWrwBWkybGT21t/g38QCSjpGUG2swlQU/ vkZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=M6cyBd5hA6OsVmAelGzV5tX+uF9n4OBWzNC5c9d9ybI=; b=e0xKyoSsB0M2n5FRAJZgk0Mng210wNfSSJjFz4fbu7x04lOdaGzmqmTHOqeLe//UuB u/mAWSCd7NbPn2hA4YzwEcU3pye/ByjsFAQzVYy/Pxi1up13tlTgUi099POabDKP8ecE GCSA6Xi+KnWZZcIB1p6JAUNqGfEeZxckkJZQHJ0eHr+DB2QLG40pSkVByY9UzvmiWsv9 T3dpKQIEh0u2pttdtXz8Tsl3of+uZXCpv/GwyPKPBCQ8Ch6QrHf9RU7fZL/MXOwlp6LK sUXA+tONIslcd9T2/tQubAnw2ccC0LgPSVVh+L8bE4Biwe/qp7gwTE+WE9SwbrjN3xZ3 WlHg== X-Gm-Message-State: APjAAAUsgdGLrfq8shH7fyCXCwy2Pz2oYTwAEK+SsKetg19mI1P63ECv eoMLTNkiu9T1Os2vAGbtt5b6hwqib2GlCT3WHQ== X-Google-Smtp-Source: APXvYqw//j8PX12o0jMJ/sTXdB0ZGAaXDk7In1PyTrMUN50VA3e5H4NhBHXZpX/7PJT5SedxTsS+zxmp8Csw1EfK6w== X-Received: by 2002:ac5:c853:: with SMTP id g19mr100310vkm.60.1565306043479; Thu, 08 Aug 2019 16:14:03 -0700 (PDT) Date: Thu, 8 Aug 2019 16:13:38 -0700 In-Reply-To: <20190808231340.53601-1-almasrymina@google.com> Message-Id: <20190808231340.53601-4-almasrymina@google.com> Mime-Version: 1.0 References: <20190808231340.53601-1-almasrymina@google.com> X-Mailer: git-send-email 2.23.0.rc1.153.gdeed80330f-goog Subject: [RFC PATCH v2 3/5] hugetlb_cgroup: Add reservation accounting for private mappings From: Mina Almasry To: mike.kravetz@oracle.com Cc: shuah@kernel.org, almasrymina@google.com, rientjes@google.com, shakeelb@google.com, gthelen@google.com, akpm@linux-foundation.org, khalid.aziz@oracle.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Normally the pointer to the cgroup to uncharge hangs off the struct page, and gets queried when it's time to free the page. With hugetlb_cgroup reservations, this is not possible. Because it's possible for a page to be reserved by one task and actually faulted in by another task. The best place to put the hugetlb_cgroup pointer to uncharge for reservations is in the resv_map. But, because the resv_map has different semantics for private and shared mappings, the code patch to charge/uncharge shared and private mappings is different. This patch implements charging and uncharging for private mappings. For private mappings, the counter to uncharge is in resv_map->reservation_counter. On initializing the resv_map this is set to NULL. On reservation of a region in private mapping, the tasks hugetlb_cgroup is charged and the hugetlb_cgroup is placed is resv_map->reservation_counter. On hugetlb_vm_op_close, we uncharge resv_map->reservation_counter. --- include/linux/hugetlb.h | 8 ++++++ include/linux/hugetlb_cgroup.h | 11 ++++++++ mm/hugetlb.c | 47 ++++++++++++++++++++++++++++++++-- mm/hugetlb_cgroup.c | 12 --------- 4 files changed, 64 insertions(+), 14 deletions(-) -- 2.23.0.rc1.153.gdeed80330f-goog diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 6777b3013345d..90b3c928d16c1 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -46,6 +46,14 @@ struct resv_map { long adds_in_progress; struct list_head region_cache; long region_cache_count; + #ifdef CONFIG_CGROUP_HUGETLB + /* + * On private mappings, the counter to uncharge reservations is stored + * here. If these fields are 0, then the mapping is shared. + */ + struct page_counter *reservation_counter; + unsigned long pages_per_hpage; +#endif }; extern struct resv_map *resv_map_alloc(void); void resv_map_release(struct kref *ref); diff --git a/include/linux/hugetlb_cgroup.h b/include/linux/hugetlb_cgroup.h index 0725f809cd2d9..1fdde63a4e775 100644 --- a/include/linux/hugetlb_cgroup.h +++ b/include/linux/hugetlb_cgroup.h @@ -25,6 +25,17 @@ struct hugetlb_cgroup; #define HUGETLB_CGROUP_MIN_ORDER 2 #ifdef CONFIG_CGROUP_HUGETLB +struct hugetlb_cgroup { + struct cgroup_subsys_state css; + /* + * the counter to account for hugepages from hugetlb. + */ + struct page_counter hugepage[HUGE_MAX_HSTATE]; + /* + * the counter to account for hugepage reservations from hugetlb. + */ + struct page_counter reserved_hugepage[HUGE_MAX_HSTATE]; +}; static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page) { diff --git a/mm/hugetlb.c b/mm/hugetlb.c index c153bef42e729..235996aef6618 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -711,6 +711,16 @@ struct resv_map *resv_map_alloc(void) INIT_LIST_HEAD(&resv_map->regions); resv_map->adds_in_progress = 0; +#ifdef CONFIG_CGROUP_HUGETLB + /* + * Initialize these to 0. On shared mappings, 0's here indicate these + * fields don't do cgroup accounting. On private mappings, these will be + * re-initialized to the proper values, to indicate that hugetlb cgroup + * reservations are to be un-charged from here. + */ + resv_map->reservation_counter = NULL; + resv_map->pages_per_hpage = 0; +#endif INIT_LIST_HEAD(&resv_map->region_cache); list_add(&rg->link, &resv_map->region_cache); @@ -3192,7 +3202,19 @@ static void hugetlb_vm_op_close(struct vm_area_struct *vma) reserve = (end - start) - region_count(resv, start, end); - kref_put(&resv->refs, resv_map_release); +#ifdef CONFIG_CGROUP_HUGETLB + /* + * Since we check for HPAGE_RESV_OWNER above, this must a private + * mapping, and these values should be none-zero, and should point to + * the hugetlb_cgroup counter to uncharge for this reservation. + */ + WARN_ON(!resv->reservation_counter); + WARN_ON(!resv->pages_per_hpage); + + hugetlb_cgroup_uncharge_counter( + resv->reservation_counter, + (end - start) * resv->pages_per_hpage); +#endif if (reserve) { /* @@ -3202,6 +3224,8 @@ static void hugetlb_vm_op_close(struct vm_area_struct *vma) gbl_reserve = hugepage_subpool_put_pages(spool, reserve); hugetlb_acct_memory(h, -gbl_reserve); } + + kref_put(&resv->refs, resv_map_release); } static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr) @@ -4516,6 +4540,7 @@ int hugetlb_reserve_pages(struct inode *inode, struct hstate *h = hstate_inode(inode); struct hugepage_subpool *spool = subpool_inode(inode); struct resv_map *resv_map; + struct hugetlb_cgroup *h_cg; long gbl_reserve; /* This should never happen */ @@ -4549,11 +4574,29 @@ int hugetlb_reserve_pages(struct inode *inode, chg = region_chg(resv_map, from, to); } else { + /* Private mapping. */ + chg = to - from; + + if (hugetlb_cgroup_charge_cgroup( + hstate_index(h), + chg * pages_per_huge_page(h), + &h_cg, true)) { + return -ENOMEM; + } + resv_map = resv_map_alloc(); if (!resv_map) return -ENOMEM; - chg = to - from; +#ifdef CONFIG_CGROUP_HUGETLB + /* + * Since this branch handles private mappings, we attach the + * counter to uncharge for this reservation off resv_map. + */ + resv_map->reservation_counter = + &h_cg->reserved_hugepage[hstate_index(h)]; + resv_map->pages_per_hpage = pages_per_huge_page(h); +#endif set_vma_resv_map(vma, resv_map); set_vma_resv_flags(vma, HPAGE_RESV_OWNER); diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c index 119176a0b2ec5..06e99ae1fec81 100644 --- a/mm/hugetlb_cgroup.c +++ b/mm/hugetlb_cgroup.c @@ -19,18 +19,6 @@ #include #include -struct hugetlb_cgroup { - struct cgroup_subsys_state css; - /* - * the counter to account for hugepages from hugetlb. - */ - struct page_counter hugepage[HUGE_MAX_HSTATE]; - /* - * the counter to account for hugepage reservations from hugetlb. - */ - struct page_counter reserved_hugepage[HUGE_MAX_HSTATE]; -}; - #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) #define MEMFILE_IDX(val) (((val) >> 16) & 0xffff) #define MEMFILE_ATTR(val) ((val) & 0xffff)