From patchwork Tue Jun 6 19:03:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ackerley Tng X-Patchwork-Id: 13269560 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E1FEC7EE2C for ; Tue, 6 Jun 2023 19:05:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238749AbjFFTEo (ORCPT ); Tue, 6 Jun 2023 15:04:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239260AbjFFTEb (ORCPT ); Tue, 6 Jun 2023 15:04:31 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DC4A173B for ; Tue, 6 Jun 2023 12:04:26 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id 41be03b00d2f7-5343c1d114cso5935810a12.0 for ; Tue, 06 Jun 2023 12:04:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1686078266; x=1688670266; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=RTPC0AoXX+NIzZnufKQytW8TkFDwziCOrc5ZhwaQeP0=; b=owBmv/2mMPcrWAYYeOz6IufYws8uNBVmJpdSLiIa/Oxif5X7cqv+vateNaoAbLjKN+ 9g8OIvY2fitd8/bF4vWCTRGtTW4cbQGYeFnSk7O/6JmITSXQUE0V5caWCidr9eoCizfR mnHihiIAiXJOu1//OF3fyNTkiIvpgOeBZOYv+VfEA9HuxcdSL1KjLzz1ww4jo+xPlynH cZu+282ONjHqqdAeelyqOrgfiIuIaT7NMZ4iSDTpZ4yPFrLEm9YlMCTiZ2Jg+4dOz9SD Af25fA3ecy4VQVCca8EotY/PKiVwegJai+On/aGLqcq8u80JQ1wIUoTEAC7FSVslSvP6 ocKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686078266; x=1688670266; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=RTPC0AoXX+NIzZnufKQytW8TkFDwziCOrc5ZhwaQeP0=; b=S8Sq9+uptJpKB3gEVf/yGmr2ThU6lTxreKx0t9uSPwdcNknIVRzlZw+X89cQn1lz9X nTxMNXmXP0Qg2jYgeSwaksj7LErLQ1NFMvJmxxoDmPbOKmEU79xuW/ZMJoJLLW3jookR UuHfdIqPIxR7wHHo/MR3/aLJUroHSP3rejwkdH53IbiNyQbk4bfZ/UdmdRuyiwzUzL7T BeoeVNxfD3OqeIMUgn/2pe57fXZSEuKSdJUUyVIHBdOHdVEAHs/IT10+485fYMFuTY4A /Hl5Xc52DuS1NlVnSAeuS1FyCIGUKRx6r6fnV12S5vIiJo7kchtZIXUFRXFfERScHQ44 8QUg== X-Gm-Message-State: AC+VfDyWdRt/1IKc2pwvHP6iCOSvrWmfxSMxq1fu5ssk+9ryB//xmNRg 0cRwCj+na8HzjbsycECn2Czp8oFk1dUFKM0UYw== X-Google-Smtp-Source: ACHHUZ7U7Xr5zqg3KoBTJpAqI34Pla/gmFzawbxWzmrT+4L/HPyaurNY1sqxQPPqj80dK4ECUufRqT2mO/+XHSgL7w== X-Received: from ackerleytng-ctop.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:13f8]) (user=ackerleytng job=sendgmr) by 2002:a65:618a:0:b0:542:9fad:de1 with SMTP id c10-20020a65618a000000b005429fad0de1mr614686pgv.12.1686078265785; Tue, 06 Jun 2023 12:04:25 -0700 (PDT) Date: Tue, 6 Jun 2023 19:03:52 +0000 In-Reply-To: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.41.0.rc0.172.g3f132b7071-goog Message-ID: <508025e09425a98d52b17cfbdc07340ae05e3e32.1686077275.git.ackerleytng@google.com> Subject: [RFC PATCH 07/19] mm: hugetlb: Refactor vma_*_reservation functions From: Ackerley Tng To: akpm@linux-foundation.org, mike.kravetz@oracle.com, muchun.song@linux.dev, pbonzini@redhat.com, seanjc@google.com, shuah@kernel.org, willy@infradead.org Cc: brauner@kernel.org, chao.p.peng@linux.intel.com, coltonlewis@google.com, david@redhat.com, dhildenb@redhat.com, dmatlack@google.com, erdemaktas@google.com, hughd@google.com, isaku.yamahata@gmail.com, jarkko@kernel.org, jmattson@google.com, joro@8bytes.org, jthoughton@google.com, jun.nakajima@intel.com, kirill.shutemov@linux.intel.com, liam.merwick@oracle.com, mail@maciej.szmigiero.name, mhocko@suse.com, michael.roth@amd.com, qperret@google.com, rientjes@google.com, rppt@kernel.org, steven.price@arm.com, tabba@google.com, vannapurve@google.com, vbabka@suse.cz, vipinsh@google.com, vkuznets@redhat.com, wei.w.wang@intel.com, yu.c.zhang@linux.intel.com, kvm@vger.kernel.org, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, qemu-devel@nongnu.org, x86@kernel.org, Ackerley Tng Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org vma_*_reservation functions rely on vma_resv_map(), which assumes on a hugetlbfs concept of the resv_map being stored in a specific field of the inode. This refactor enables vma_*_reservation functions, now renamed resv_map_*_reservation, to be used with non-hugetlbfs filesystems, further decoupling hugetlb from hugetlbfs. Signed-off-by: Ackerley Tng --- mm/hugetlb.c | 184 +++++++++++++++++++++++++++------------------------ 1 file changed, 99 insertions(+), 85 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index d16c6417b90f..d943f83d15a9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2643,89 +2643,81 @@ static void return_unused_surplus_pages(struct hstate *h, /* - * vma_needs_reservation, vma_commit_reservation and vma_end_reservation - * are used by the huge page allocation routines to manage reservations. + * resv_map_needs_reservation, resv_map_commit_reservation and + * resv_map_end_reservation are used by the huge page allocation routines to + * manage reservations. * - * vma_needs_reservation is called to determine if the huge page at addr - * within the vma has an associated reservation. If a reservation is - * needed, the value 1 is returned. The caller is then responsible for - * managing the global reservation and subpool usage counts. After - * the huge page has been allocated, vma_commit_reservation is called - * to add the page to the reservation map. If the page allocation fails, - * the reservation must be ended instead of committed. vma_end_reservation - * is called in such cases. + * resv_map_needs_reservation is called to determine if the huge page at addr + * within the vma has an associated reservation. If a reservation is needed, + * the value 1 is returned. The caller is then responsible for managing the + * global reservation and subpool usage counts. After the huge page has been + * allocated, resv_map_commit_reservation is called to add the page to the + * reservation map. If the page allocation fails, the reservation must be ended + * instead of committed. resv_map_end_reservation is called in such cases. * - * In the normal case, vma_commit_reservation returns the same value - * as the preceding vma_needs_reservation call. The only time this - * is not the case is if a reserve map was changed between calls. It - * is the responsibility of the caller to notice the difference and - * take appropriate action. + * In the normal case, resv_map_commit_reservation returns the same value as the + * preceding resv_map_needs_reservation call. The only time this is not the + * case is if a reserve map was changed between calls. It is the responsibility + * of the caller to notice the difference and take appropriate action. * - * vma_add_reservation is used in error paths where a reservation must - * be restored when a newly allocated huge page must be freed. It is - * to be called after calling vma_needs_reservation to determine if a - * reservation exists. + * resv_map_add_reservation is used in error paths where a reservation must be + * restored when a newly allocated huge page must be freed. It is to be called + * after calling resv_map_needs_reservation to determine if a reservation + * exists. * - * vma_del_reservation is used in error paths where an entry in the reserve - * map was created during huge page allocation and must be removed. It is to - * be called after calling vma_needs_reservation to determine if a reservation + * resv_map_del_reservation is used in error paths where an entry in the reserve + * map was created during huge page allocation and must be removed. It is to be + * called after calling resv_map_needs_reservation to determine if a reservation * exists. */ -enum vma_resv_mode { - VMA_NEEDS_RESV, - VMA_COMMIT_RESV, - VMA_END_RESV, - VMA_ADD_RESV, - VMA_DEL_RESV, +enum resv_map_resv_mode { + RESV_MAP_NEEDS_RESV, + RESV_MAP_COMMIT_RESV, + RESV_MAP_END_RESV, + RESV_MAP_ADD_RESV, + RESV_MAP_DEL_RESV, }; -static long __vma_reservation_common(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr, - enum vma_resv_mode mode) +static long __resv_map_reservation_common(struct resv_map *resv, pgoff_t resv_index, + bool may_be_shared_mapping, + enum resv_map_resv_mode mode) { - struct resv_map *resv; - pgoff_t idx; long ret; long dummy_out_regions_needed; - resv = vma_resv_map(vma); - if (!resv) - return 1; - - idx = vma_hugecache_offset(h, vma, addr); switch (mode) { - case VMA_NEEDS_RESV: - ret = region_chg(resv, idx, idx + 1, &dummy_out_regions_needed); + case RESV_MAP_NEEDS_RESV: + ret = region_chg(resv, resv_index, resv_index + 1, &dummy_out_regions_needed); /* We assume that vma_reservation_* routines always operate on * 1 page, and that adding to resv map a 1 page entry can only * ever require 1 region. */ VM_BUG_ON(dummy_out_regions_needed != 1); break; - case VMA_COMMIT_RESV: - ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); + case RESV_MAP_COMMIT_RESV: + ret = region_add(resv, resv_index, resv_index + 1, 1, NULL, NULL); /* region_add calls of range 1 should never fail. */ VM_BUG_ON(ret < 0); break; - case VMA_END_RESV: - region_abort(resv, idx, idx + 1, 1); + case RESV_MAP_END_RESV: + region_abort(resv, resv_index, resv_index + 1, 1); ret = 0; break; - case VMA_ADD_RESV: - if (vma->vm_flags & VM_MAYSHARE) { - ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); + case RESV_MAP_ADD_RESV: + if (may_be_shared_mapping) { + ret = region_add(resv, resv_index, resv_index + 1, 1, NULL, NULL); /* region_add calls of range 1 should never fail. */ VM_BUG_ON(ret < 0); } else { - region_abort(resv, idx, idx + 1, 1); - ret = region_del(resv, idx, idx + 1); + region_abort(resv, resv_index, resv_index + 1, 1); + ret = region_del(resv, resv_index, resv_index + 1); } break; - case VMA_DEL_RESV: - if (vma->vm_flags & VM_MAYSHARE) { - region_abort(resv, idx, idx + 1, 1); - ret = region_del(resv, idx, idx + 1); + case RESV_MAP_DEL_RESV: + if (may_be_shared_mapping) { + region_abort(resv, resv_index, resv_index + 1, 1); + ret = region_del(resv, resv_index, resv_index + 1); } else { - ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); + ret = region_add(resv, resv_index, resv_index + 1, 1, NULL, NULL); /* region_add calls of range 1 should never fail. */ VM_BUG_ON(ret < 0); } @@ -2734,7 +2726,7 @@ static long __vma_reservation_common(struct hstate *h, BUG(); } - if (vma->vm_flags & VM_MAYSHARE || mode == VMA_DEL_RESV) + if (may_be_shared_mapping || mode == RESV_MAP_DEL_RESV) return ret; /* * We know private mapping must have HPAGE_RESV_OWNER set. @@ -2758,34 +2750,39 @@ static long __vma_reservation_common(struct hstate *h, return ret; } -static long vma_needs_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) +static long resv_map_needs_reservation(struct resv_map *resv, pgoff_t resv_index, + bool may_be_shared_mapping) { - return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); + return __resv_map_reservation_common( + resv, resv_index, may_be_shared_mapping, RESV_MAP_NEEDS_RESV); } -static long vma_commit_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) +static long resv_map_commit_reservation(struct resv_map *resv, pgoff_t resv_index, + bool may_be_shared_mapping) { - return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); + return __resv_map_reservation_common( + resv, resv_index, may_be_shared_mapping, RESV_MAP_COMMIT_RESV); } -static void vma_end_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) +static void resv_map_end_reservation(struct resv_map *resv, pgoff_t resv_index, + bool may_be_shared_mapping) { - (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); + (void)__resv_map_reservation_common( + resv, resv_index, may_be_shared_mapping, RESV_MAP_END_RESV); } -static long vma_add_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) +static long resv_map_add_reservation(struct resv_map *resv, pgoff_t resv_index, + bool may_be_shared_mapping) { - return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV); + return __resv_map_reservation_common( + resv, resv_index, may_be_shared_mapping, RESV_MAP_ADD_RESV); } -static long vma_del_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) +static long resv_map_del_reservation(struct resv_map *resv, pgoff_t resv_index, + bool may_be_shared_mapping) { - return __vma_reservation_common(h, vma, addr, VMA_DEL_RESV); + return __resv_map_reservation_common( + resv, resv_index, may_be_shared_mapping, RESV_MAP_DEL_RESV); } /* @@ -2811,7 +2808,12 @@ static long vma_del_reservation(struct hstate *h, void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, unsigned long address, struct folio *folio) { - long rc = vma_needs_reservation(h, vma, address); + long rc; + struct resv_map *resv = vma_resv_map(vma); + pgoff_t resv_index = vma_hugecache_offset(h, vma, address); + bool may_share = vma->vm_flags & VM_MAYSHARE; + + rc = resv_map_needs_reservation(resv, resv_index, may_share); if (folio_test_hugetlb_restore_reserve(folio)) { if (unlikely(rc < 0)) @@ -2828,9 +2830,9 @@ void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, */ folio_clear_hugetlb_restore_reserve(folio); else if (rc) - (void)vma_add_reservation(h, vma, address); + (void)resv_map_add_reservation(resv, resv_index, may_share); else - vma_end_reservation(h, vma, address); + resv_map_end_reservation(resv, resv_index, may_share); } else { if (!rc) { /* @@ -2841,7 +2843,7 @@ void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, * Remove the entry so that a subsequent allocation * does not consume a reservation. */ - rc = vma_del_reservation(h, vma, address); + rc = resv_map_del_reservation(resv, resv_index, may_share); if (rc < 0) /* * VERY rare out of memory condition. Since @@ -2855,7 +2857,7 @@ void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, } else if (rc < 0) { /* * Rare out of memory condition from - * vma_needs_reservation call. Memory allocation is + * resv_map_needs_reservation call. Memory allocation is * only attempted if a new entry is needed. Therefore, * this implies there is not an entry in the * reserve map. @@ -2877,7 +2879,7 @@ void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, /* * No reservation present, do nothing */ - vma_end_reservation(h, vma, address); + resv_map_end_reservation(resv, resv_index, may_share); } } @@ -3019,13 +3021,17 @@ struct folio *alloc_hugetlb_folio_from_subpool( struct hugetlb_cgroup *h_cg = NULL; bool deferred_reserve; + struct resv_map *resv = vma_resv_map(vma); + pgoff_t resv_index = vma_hugecache_offset(h, vma, addr); + bool may_share = vma->vm_flags & VM_MAYSHARE; + idx = hstate_index(h); /* * Examine the region/reserve map to determine if the process * has a reservation for the page to be allocated. A return * code of zero indicates a reservation exists (no change). */ - map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); + map_chg = gbl_chg = resv_map_needs_reservation(resv, resv_index, may_share); if (map_chg < 0) return ERR_PTR(-ENOMEM); @@ -3039,7 +3045,7 @@ struct folio *alloc_hugetlb_folio_from_subpool( if (map_chg || avoid_reserve) { gbl_chg = hugepage_subpool_get_pages(spool, 1); if (gbl_chg < 0) { - vma_end_reservation(h, vma, addr); + resv_map_end_reservation(resv, resv_index, may_share); return ERR_PTR(-ENOSPC); } @@ -3104,11 +3110,11 @@ struct folio *alloc_hugetlb_folio_from_subpool( hugetlb_set_folio_subpool(folio, spool); - map_commit = vma_commit_reservation(h, vma, addr); + map_commit = resv_map_commit_reservation(resv, resv_index, may_share); if (unlikely(map_chg > map_commit)) { /* * The page was added to the reservation map between - * vma_needs_reservation and vma_commit_reservation. + * resv_map_needs_reservation and resv_map_commit_reservation. * This indicates a race with hugetlb_reserve_pages. * Adjust for the subpool count incremented above AND * in hugetlb_reserve_pages for the same page. Also, @@ -3134,7 +3140,7 @@ struct folio *alloc_hugetlb_folio_from_subpool( out_subpool_put: if (map_chg || avoid_reserve) hugepage_subpool_put_pages(spool, 1); - vma_end_reservation(h, vma, addr); + resv_map_end_reservation(resv, resv_index, may_share); return ERR_PTR(-ENOSPC); } @@ -5901,12 +5907,16 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, * the spinlock. */ if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { - if (vma_needs_reservation(h, vma, haddr) < 0) { + struct resv_map *resv = vma_resv_map(vma); + pgoff_t resv_index = vma_hugecache_offset(h, vma, address); + bool may_share = vma->vm_flags & VM_MAYSHARE; + + if (resv_map_needs_reservation(resv, resv_index, may_share) < 0) { ret = VM_FAULT_OOM; goto backout_unlocked; } /* Just decrements count, does not deallocate */ - vma_end_reservation(h, vma, haddr); + resv_map_end_reservation(resv, resv_index, may_share); } ptl = huge_pte_lock(h, mm, ptep); @@ -6070,12 +6080,16 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, */ if ((flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) && !(vma->vm_flags & VM_MAYSHARE) && !huge_pte_write(entry)) { - if (vma_needs_reservation(h, vma, haddr) < 0) { + struct resv_map *resv = vma_resv_map(vma); + pgoff_t resv_index = vma_hugecache_offset(h, vma, address); + bool may_share = vma->vm_flags & VM_MAYSHARE; + + if (resv_map_needs_reservation(resv, resv_index, may_share) < 0) { ret = VM_FAULT_OOM; goto out_mutex; } /* Just decrements count, does not deallocate */ - vma_end_reservation(h, vma, haddr); + resv_map_end_reservation(resv, resv_index, may_share); pagecache_folio = filemap_lock_folio(mapping, idx); }