From patchwork Sun Oct 13 00:30:21 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 11187195 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8B408112B for ; Sun, 13 Oct 2019 00:31:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5ADCA222BD for ; Sun, 13 Oct 2019 00:31:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="uBRme8l1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728537AbfJMAbK (ORCPT ); Sat, 12 Oct 2019 20:31:10 -0400 Received: from mail-pf1-f201.google.com ([209.85.210.201]:33063 "EHLO mail-pf1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728818AbfJMAao (ORCPT ); Sat, 12 Oct 2019 20:30:44 -0400 Received: by mail-pf1-f201.google.com with SMTP id z4so10660139pfn.0 for ; Sat, 12 Oct 2019 17:30:42 -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=LHbD1B91xdGNIRrZOTEf3dBGFn0prBcVwxkD9ZnMONk=; b=uBRme8l1r2nKIYeN05YBhUI6knKKwaG9a+9GFNYD9eBMZ9Z2hATV2tGBfpiVsm1LJ3 QIkGjc3b9Cv9hBbtZWEV6C7Yh31smOG4bJKjhPbMeK6XnTaasRrNGnMSqszavrb7tk1S 3Ic5TzRyL77sg5IEcYoIoqdVH847XNty/j/SOmNQKSpWH7adbDiz9QyRnA+DzWcLXDb8 ok90UFF/QT15fIm99rnTlp9DYcoT3ZPd6y+mQTRsyhCXKdIosvFGbRbtibxmxVH856fE blUoepV7M4ViY4+XDwA3UihybZRJEHT1stWQijQAqB7lUZLVCujwSkCBtXFw1dHJnDpQ 9Z+A== 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=LHbD1B91xdGNIRrZOTEf3dBGFn0prBcVwxkD9ZnMONk=; b=VQeRNpHjaV3aErDj1q6RscKrsrrl+tM7GMiU8c4PdMWY5saImmT17Lrwb84XggSguA h6GuB1DFray8AhOw0fqL9Ga68Ufqs/R/nlDgPaYSZW6UK0fJq50tHv8uQwg8DZA8U2qG jgwx4VJ9nSgryEwCyyWSkODN7cGfLQZFymp7E0Ze0eD9/iKbH3aoBwkcDIUwtxLwL7Nj /nbW8KdJRdkPgpNsFIrubrrl+bcZDKKX7AaimWA+eJdIxjlrD3+yTRgY8QswoKAtw29z XisRmZqmPMFmSgy0qowihOFxDfYwV3qEQGe3Bei/Q2kAcRe6MokzaiSajO2+fuJIiBQ8 vjRg== X-Gm-Message-State: APjAAAUqnzcd701ilLly7aFdNtiuE4mK2MqdSo6QpZqPJaN/eThHz77P 9c38ApU4u+dwvVDYhCc8z7VSfllP3Kbp08sbCQ== X-Google-Smtp-Source: APXvYqxkNR0wQCE/4rnpDdVUsJzyn46jJAt1BU9w53Atd8G2RenjUc0Fwe/LgYPbRpKmD659JZXqZIfHKC+oUobNEg== X-Received: by 2002:a65:6096:: with SMTP id t22mr24472289pgu.409.1570926641714; Sat, 12 Oct 2019 17:30:41 -0700 (PDT) Date: Sat, 12 Oct 2019 17:30:21 -0700 In-Reply-To: <20191013003024.215429-1-almasrymina@google.com> Message-Id: <20191013003024.215429-6-almasrymina@google.com> Mime-Version: 1.0 References: <20191013003024.215429-1-almasrymina@google.com> X-Mailer: git-send-email 2.23.0.700.g56cf767bdb-goog Subject: [PATCH v6 6/9] hugetlb_cgroup: add accounting for shared 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, cgroups@vger.kernel.org, aneesh.kumar@linux.vnet.ibm.com, mkoutny@suse.com Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org For shared mappings, the pointer to the hugetlb_cgroup to uncharge lives in the resv_map entries, in file_region->reservation_counter. After a call to region_chg, we charge the approprate hugetlb_cgroup, and if successful, we pass on the hugetlb_cgroup info to a follow up region_add call. When a file_region entry is added to the resv_map via region_add, we put the pointer to that cgroup in file_region->reservation_counter. If charging doesn't succeed, we report the error to the caller, so that the kernel fails the reservation. On region_del, which is when the hugetlb memory is unreserved, we also uncharge the file_region->reservation_counter. Signed-off-by: Mina Almasry --- mm/hugetlb.c | 147 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 116 insertions(+), 31 deletions(-) -- 2.23.0.700.g56cf767bdb-goog diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f9c1947925bb9..af336bf227fb6 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -242,6 +242,15 @@ struct file_region { struct list_head link; long from; long to; +#ifdef CONFIG_CGROUP_HUGETLB + /* + * On shared mappings, each reserved region appears as a struct + * file_region in resv_map. These fields hold the info needed to + * uncharge each reservation. + */ + struct page_counter *reservation_counter; + unsigned long pages_per_hpage; +#endif }; /* Helper that removes a struct file_region from the resv_map cache and returns @@ -250,12 +259,30 @@ struct file_region { static struct file_region * get_file_region_entry_from_cache(struct resv_map *resv, long from, long to); +/* Helper that records hugetlb_cgroup uncharge info. */ +static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg, + struct file_region *nrg, + struct hstate *h) +{ +#ifdef CONFIG_CGROUP_HUGETLB + if (h_cg) { + nrg->reservation_counter = + &h_cg->reserved_hugepage[hstate_index(h)]; + nrg->pages_per_hpage = pages_per_huge_page(h); + } else { + nrg->reservation_counter = NULL; + nrg->pages_per_hpage = 0; + } +#endif +} + /* Must be called with resv->lock held. Calling this with count_only == true * will count the number of pages to be added but will not modify the linked * list. */ static long add_reservation_in_range(struct resv_map *resv, long f, long t, - bool count_only) + struct hugetlb_cgroup *h_cg, + struct hstate *h, bool count_only) { long add = 0; struct list_head *head = &resv->regions; @@ -291,6 +318,8 @@ static long add_reservation_in_range(struct resv_map *resv, long f, long t, if (!count_only) { nrg = get_file_region_entry_from_cache( resv, last_accounted_offset, rg->from); + record_hugetlb_cgroup_uncharge_info(h_cg, nrg, + h); list_add(&nrg->link, rg->link.prev); } } @@ -306,11 +335,13 @@ static long add_reservation_in_range(struct resv_map *resv, long f, long t, if (!count_only) { nrg = get_file_region_entry_from_cache( resv, last_accounted_offset, t); + record_hugetlb_cgroup_uncharge_info(h_cg, nrg, h); list_add(&nrg->link, rg->link.prev); } last_accounted_offset = t; } + VM_BUG_ON(add < 0); return add; } @@ -327,7 +358,8 @@ static long add_reservation_in_range(struct resv_map *resv, long f, long t, * Return the number of new huge pages added to the map. This * number is greater than or equal to zero. */ -static long region_add(struct resv_map *resv, long f, long t, +static long region_add(struct hstate *h, struct hugetlb_cgroup *h_cg, + struct resv_map *resv, long f, long t, long regions_needed) { long add = 0; @@ -336,7 +368,7 @@ static long region_add(struct resv_map *resv, long f, long t, VM_BUG_ON(resv->region_cache_count < regions_needed); - add = add_reservation_in_range(resv, f, t, false); + add = add_reservation_in_range(resv, f, t, h_cg, h, false); resv->adds_in_progress -= regions_needed; spin_unlock(&resv->lock); @@ -398,7 +430,7 @@ static long region_chg(struct resv_map *resv, long f, long t, } /* Count how many hugepages in this range are NOT respresented. */ - chg = add_reservation_in_range(resv, f, t, true); + chg = add_reservation_in_range(resv, f, t, NULL, NULL, true); spin_unlock(&resv->lock); return chg; @@ -425,6 +457,24 @@ static void region_abort(struct resv_map *resv, long f, long t, spin_unlock(&resv->lock); } +static void uncharge_cgroup_if_shared_mapping(struct resv_map *resv, + struct file_region *rg, + unsigned long nr_pages) +{ +#ifdef CONFIG_CGROUP_HUGETLB + /* + * If resv->reservation_counter is NULL, then this is shared + * reservation, and the reserved memory is tracked in the file_struct + * entries inside of resv_map. So we need to uncharge the memory here. + */ + if (rg->reservation_counter && rg->pages_per_hpage && nr_pages > 0 && + !resv->reservation_counter) { + hugetlb_cgroup_uncharge_counter(rg->reservation_counter, + nr_pages * rg->pages_per_hpage); + } +#endif +} + /* * Delete the specified range [f, t) from the reserve map. If the * t parameter is LONG_MAX, this indicates that ALL regions after f @@ -494,6 +544,9 @@ static long region_del(struct resv_map *resv, long f, long t) /* Original entry is trimmed */ rg->to = f; + uncharge_cgroup_if_shared_mapping(resv, rg, + nrg->to - nrg->from); + list_add(&nrg->link, &rg->link); nrg = NULL; break; @@ -501,6 +554,8 @@ static long region_del(struct resv_map *resv, long f, long t) if (f <= rg->from && t >= rg->to) { /* Remove entire region */ del += rg->to - rg->from; + uncharge_cgroup_if_shared_mapping(resv, rg, + rg->to - rg->from); list_del(&rg->link); kfree(rg); continue; @@ -509,14 +564,20 @@ static long region_del(struct resv_map *resv, long f, long t) if (f <= rg->from) { /* Trim beginning of region */ del += t - rg->from; rg->from = t; + + uncharge_cgroup_if_shared_mapping(resv, rg, + t - rg->from); } else { /* Trim end of region */ del += rg->to - f; rg->to = f; + + uncharge_cgroup_if_shared_mapping(resv, rg, rg->to - f); } } spin_unlock(&resv->lock); kfree(nrg); + return del; } @@ -1923,7 +1984,8 @@ __vma_reservation_common(struct hstate *h, struct vm_area_struct *vma, break; case VMA_COMMIT_RESV: VM_BUG_ON(in_regions_needed == -1); - ret = region_add(resv, idx, idx + 1, in_regions_needed); + ret = region_add(NULL, NULL, resv, idx, idx + 1, + in_regions_needed); break; case VMA_END_RESV: VM_BUG_ON(in_regions_needed == -1); @@ -1933,7 +1995,8 @@ __vma_reservation_common(struct hstate *h, struct vm_area_struct *vma, case VMA_ADD_RESV: VM_BUG_ON(in_regions_needed == -1); if (vma->vm_flags & VM_MAYSHARE) - ret = region_add(resv, idx, idx + 1, in_regions_needed); + ret = region_add(NULL, NULL, resv, idx, idx + 1, + in_regions_needed); else { region_abort(resv, idx, idx + 1, in_regions_needed); ret = region_del(resv, idx, idx + 1); @@ -4603,7 +4666,7 @@ 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; + struct hugetlb_cgroup *h_cg = NULL; long gbl_reserve, regions_needed = 0; /* This should never happen */ @@ -4644,23 +4707,6 @@ int hugetlb_reserve_pages(struct inode *inode, chg = to - from; - if (hugetlb_cgroup_charge_cgroup(hstate_index(h), - chg * pages_per_huge_page(h), - &h_cg, true)) { - kref_put(&resv_map->refs, resv_map_release); - return -ENOMEM; - } - -#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); } @@ -4670,6 +4716,25 @@ int hugetlb_reserve_pages(struct inode *inode, goto out_err; } + ret = hugetlb_cgroup_charge_cgroup( + hstate_index(h), chg * pages_per_huge_page(h), &h_cg, true); + + if (ret < 0) { + ret = -ENOMEM; + goto out_err; + } + +#ifdef CONFIG_CGROUP_HUGETLB + if (vma && !(vma->vm_flags & VM_MAYSHARE)) { + /* For private mappings, the hugetlb_cgroup uncharge info hangs + * of the resv_map. + */ + resv_map->reservation_counter = + &h_cg->reserved_hugepage[hstate_index(h)]; + resv_map->pages_per_hpage = pages_per_huge_page(h); + } +#endif + /* * There must be enough pages in the subpool for the mapping. If * the subpool has a minimum size, there may be some global @@ -4678,7 +4743,7 @@ int hugetlb_reserve_pages(struct inode *inode, gbl_reserve = hugepage_subpool_get_pages(spool, chg); if (gbl_reserve < 0) { ret = -ENOSPC; - goto out_err; + goto out_uncharge_cgroup; } /* @@ -4687,9 +4752,7 @@ int hugetlb_reserve_pages(struct inode *inode, */ ret = hugetlb_acct_memory(h, gbl_reserve); if (ret < 0) { - /* put back original number of pages, chg */ - (void)hugepage_subpool_put_pages(spool, chg); - goto out_err; + goto out_put_pages; } /* @@ -4704,7 +4767,8 @@ int hugetlb_reserve_pages(struct inode *inode, * else has to be done for private mappings here */ if (!vma || vma->vm_flags & VM_MAYSHARE) { - long add = region_add(resv_map, from, to, regions_needed); + long add = + region_add(h, h_cg, resv_map, from, to, regions_needed); if (unlikely(chg > add)) { /* @@ -4716,12 +4780,33 @@ int hugetlb_reserve_pages(struct inode *inode, */ long rsv_adjust; - rsv_adjust = hugepage_subpool_put_pages(spool, - chg - add); + hugetlb_cgroup_uncharge_cgroup( + hstate_index(h), + (chg - add) * pages_per_huge_page(h), h_cg, + true); + + rsv_adjust = + hugepage_subpool_put_pages(spool, chg - add); hugetlb_acct_memory(h, -rsv_adjust); } + } else { +#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 } return 0; +out_put_pages: + /* put back original number of pages, chg */ + (void)hugepage_subpool_put_pages(spool, chg); +out_uncharge_cgroup: + hugetlb_cgroup_uncharge_cgroup( + hstate_index(h), chg * pages_per_huge_page(h), h_cg, true); out_err: if (!vma || vma->vm_flags & VM_MAYSHARE) /* Don't call region_abort if region_chg failed */