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Tue, 24 Sep 2024 03:17:10 -0700 (PDT) From: Dev Jain To: akpm@linux-foundation.org, david@redhat.com, willy@infradead.org, kirill.shutemov@linux.intel.com Cc: ryan.roberts@arm.com, anshuman.khandual@arm.com, catalin.marinas@arm.com, cl@gentwo.org, vbabka@suse.cz, mhocko@suse.com, apopple@nvidia.com, dave.hansen@linux.intel.com, will@kernel.org, baohua@kernel.org, jack@suse.cz, mark.rutland@arm.com, hughd@google.com, aneesh.kumar@kernel.org, yang@os.amperecomputing.com, peterx@redhat.com, ioworker0@gmail.com, jglisse@google.com, wangkefeng.wang@huawei.com, ziy@nvidia.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Dev Jain Subject: [PATCH v5 1/2] mm: Abstract THP allocation Date: Tue, 24 Sep 2024 15:46:53 +0530 Message-Id: <20240924101654.1777697-2-dev.jain@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240924101654.1777697-1-dev.jain@arm.com> References: <20240924101654.1777697-1-dev.jain@arm.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: E677040010 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: gkegwa15baxr1moc8p4rhujwyeajyjmr X-HE-Tag: 1727173040-219264 X-HE-Meta: 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 URCwgInX 78pDJpoxSqzvbUJIT8VllZ8PIDdQ2WFrwqTPuOYU/COWBk9xYrMjnLwbKwRkMCixEoDMmcYquGEImnc7COHMoD3x+kEY64EN6vRULB8oXDNjkJT4Kp3giFLhLV+aF9RriGW1P0yVfcQ7jFRm/4aQe9P+oKaHl9zIMX1VhfNA/BBRm8FpwsG7wUAN51WBRB/UUEwtMcRJOLakxHZ0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: In preparation for the second patch, abstract away the THP allocation logic present in the create_huge_pmd() path, which corresponds to the faulting case when no page is present. There should be no functional change as a result of applying this patch, except that, as David notes at [1], a PMD-aligned address should be passed to update_mmu_cache_pmd(). [1]: https://lore.kernel.org/all/ddd3fcd2-48b3-4170-bcaa-2fe66e093f43@redhat.com/ Acked-by: David Hildenbrand Signed-off-by: Dev Jain Reviewed-by: Kefeng Wang --- mm/huge_memory.c | 98 ++++++++++++++++++++++++++++-------------------- 1 file changed, 57 insertions(+), 41 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 4e34b7f89daf..bdbf67c18f6c 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1148,47 +1148,81 @@ unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr, } EXPORT_SYMBOL_GPL(thp_get_unmapped_area); -static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, - struct page *page, gfp_t gfp) +static struct folio *vma_alloc_anon_folio_pmd(struct vm_area_struct *vma, + unsigned long addr) { - struct vm_area_struct *vma = vmf->vma; - struct folio *folio = page_folio(page); - pgtable_t pgtable; - unsigned long haddr = vmf->address & HPAGE_PMD_MASK; - vm_fault_t ret = 0; + unsigned long haddr = addr & HPAGE_PMD_MASK; + gfp_t gfp = vma_thp_gfp_mask(vma); + const int order = HPAGE_PMD_ORDER; + struct folio *folio = vma_alloc_folio(gfp, order, vma, haddr, true); - VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); + if (unlikely(!folio)) { + count_vm_event(THP_FAULT_FALLBACK); + count_mthp_stat(order, MTHP_STAT_ANON_FAULT_FALLBACK); + goto out; + } + VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); if (mem_cgroup_charge(folio, vma->vm_mm, gfp)) { folio_put(folio); count_vm_event(THP_FAULT_FALLBACK); count_vm_event(THP_FAULT_FALLBACK_CHARGE); - count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_FALLBACK); - count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE); - return VM_FAULT_FALLBACK; + count_mthp_stat(order, MTHP_STAT_ANON_FAULT_FALLBACK); + count_mthp_stat(order, MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE); + return NULL; } folio_throttle_swaprate(folio, gfp); - pgtable = pte_alloc_one(vma->vm_mm); - if (unlikely(!pgtable)) { - ret = VM_FAULT_OOM; - goto release; - } - - folio_zero_user(folio, vmf->address); + folio_zero_user(folio, addr); /* * The memory barrier inside __folio_mark_uptodate makes sure that * folio_zero_user writes become visible before the set_pmd_at() * write. */ __folio_mark_uptodate(folio); +out: + return folio; +} + +static void map_anon_folio_pmd(struct folio *folio, pmd_t *pmd, + struct vm_area_struct *vma, unsigned long haddr) +{ + pmd_t entry; + + entry = mk_huge_pmd(&folio->page, vma->vm_page_prot); + entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); + folio_add_new_anon_rmap(folio, vma, haddr, RMAP_EXCLUSIVE); + folio_add_lru_vma(folio, vma); + set_pmd_at(vma->vm_mm, haddr, pmd, entry); + update_mmu_cache_pmd(vma, haddr, pmd); + add_mm_counter(vma->vm_mm, MM_ANONPAGES, HPAGE_PMD_NR); + count_vm_event(THP_FAULT_ALLOC); + count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_ALLOC); + count_memcg_event_mm(vma->vm_mm, THP_FAULT_ALLOC); +} + +static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf) +{ + unsigned long haddr = vmf->address & HPAGE_PMD_MASK; + struct vm_area_struct *vma = vmf->vma; + struct folio *folio; + pgtable_t pgtable; + vm_fault_t ret = 0; + + folio = vma_alloc_anon_folio_pmd(vma, vmf->address); + if (unlikely(!folio)) + return VM_FAULT_FALLBACK; + + pgtable = pte_alloc_one(vma->vm_mm); + if (unlikely(!pgtable)) { + ret = VM_FAULT_OOM; + goto release; + } vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd); if (unlikely(!pmd_none(*vmf->pmd))) { goto unlock_release; } else { - pmd_t entry; - ret = check_stable_address_space(vma->vm_mm); if (ret) goto unlock_release; @@ -1202,21 +1236,11 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, VM_BUG_ON(ret & VM_FAULT_FALLBACK); return ret; } - - entry = mk_huge_pmd(page, vma->vm_page_prot); - entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); - folio_add_new_anon_rmap(folio, vma, haddr, RMAP_EXCLUSIVE); - folio_add_lru_vma(folio, vma); pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable); - set_pmd_at(vma->vm_mm, haddr, vmf->pmd, entry); - update_mmu_cache_pmd(vma, vmf->address, vmf->pmd); - add_mm_counter(vma->vm_mm, MM_ANONPAGES, HPAGE_PMD_NR); + map_anon_folio_pmd(folio, vmf->pmd, vma, haddr); mm_inc_nr_ptes(vma->vm_mm); deferred_split_folio(folio, false); spin_unlock(vmf->ptl); - count_vm_event(THP_FAULT_ALLOC); - count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_ALLOC); - count_memcg_event_mm(vma->vm_mm, THP_FAULT_ALLOC); } return 0; @@ -1283,8 +1307,6 @@ static void set_huge_zero_folio(pgtable_t pgtable, struct mm_struct *mm, vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; - gfp_t gfp; - struct folio *folio; unsigned long haddr = vmf->address & HPAGE_PMD_MASK; vm_fault_t ret; @@ -1335,14 +1357,8 @@ vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf) } return ret; } - gfp = vma_thp_gfp_mask(vma); - folio = vma_alloc_folio(gfp, HPAGE_PMD_ORDER, vma, haddr, true); - if (unlikely(!folio)) { - count_vm_event(THP_FAULT_FALLBACK); - count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_FALLBACK); - return VM_FAULT_FALLBACK; - } - return __do_huge_pmd_anonymous_page(vmf, &folio->page, gfp); + + return __do_huge_pmd_anonymous_page(vmf); } static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, From patchwork Tue Sep 24 10:16:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dev Jain X-Patchwork-Id: 13810681 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8F88CF9C71 for ; Tue, 24 Sep 2024 10:17:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 75BD16B008C; Tue, 24 Sep 2024 06:17:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 70B336B0092; Tue, 24 Sep 2024 06:17:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5FA9E6B0093; Tue, 24 Sep 2024 06:17:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 442606B008C for ; 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Tue, 24 Sep 2024 03:17:20 -0700 (PDT) From: Dev Jain To: akpm@linux-foundation.org, david@redhat.com, willy@infradead.org, kirill.shutemov@linux.intel.com Cc: ryan.roberts@arm.com, anshuman.khandual@arm.com, catalin.marinas@arm.com, cl@gentwo.org, vbabka@suse.cz, mhocko@suse.com, apopple@nvidia.com, dave.hansen@linux.intel.com, will@kernel.org, baohua@kernel.org, jack@suse.cz, mark.rutland@arm.com, hughd@google.com, aneesh.kumar@kernel.org, yang@os.amperecomputing.com, peterx@redhat.com, ioworker0@gmail.com, jglisse@google.com, wangkefeng.wang@huawei.com, ziy@nvidia.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Dev Jain Subject: [PATCH v5 2/2] mm: Allocate THP on hugezeropage wp-fault Date: Tue, 24 Sep 2024 15:46:54 +0530 Message-Id: <20240924101654.1777697-3-dev.jain@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240924101654.1777697-1-dev.jain@arm.com> References: <20240924101654.1777697-1-dev.jain@arm.com> MIME-Version: 1.0 X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 5C0AD40014 X-Stat-Signature: ifyajwz3mnjehnj5m5uxjfbw718sktgd X-Rspam-User: X-HE-Tag: 1727173050-194666 X-HE-Meta: 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 CL+OBA9y asPw9j84va0lFwH10YTIRWFgw9YYA/OFM4SjlXGf60YRrgRNeoxDBSqaqMVcNiZg6WOprGqiduRUG+iKQGKD2zOxdiat0x/KpNJ4uTVC8gbAnEqDMs1+YPbslhHTKd9kAzU2xy5AUnPfwc4wjoJTEApSRVA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Introduce do_huge_zero_wp_pmd() to handle wp-fault on a hugezeropage and replace it with a PMD-mapped THP. Remember to flush TLB entry corresponding to the hugezeropage. In case of failure, fallback to splitting the PMD. Signed-off-by: Dev Jain Acked-by: David Hildenbrand Reviewed-by: Kefeng Wang --- mm/huge_memory.c | 44 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 43 insertions(+), 1 deletion(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index bdbf67c18f6c..fbb195bc2038 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1790,6 +1790,41 @@ void huge_pmd_set_accessed(struct vm_fault *vmf) spin_unlock(vmf->ptl); } +static vm_fault_t do_huge_zero_wp_pmd(struct vm_fault *vmf) +{ + unsigned long haddr = vmf->address & HPAGE_PMD_MASK; + struct vm_area_struct *vma = vmf->vma; + struct mmu_notifier_range range; + struct folio *folio; + vm_fault_t ret = 0; + + folio = vma_alloc_anon_folio_pmd(vma, vmf->address); + if (unlikely(!folio)) { + ret = VM_FAULT_FALLBACK; + goto out; + } + + mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma->vm_mm, haddr, + haddr + HPAGE_PMD_SIZE); + mmu_notifier_invalidate_range_start(&range); + vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd); + if (unlikely(!pmd_same(pmdp_get(vmf->pmd), vmf->orig_pmd))) + goto release; + ret = check_stable_address_space(vma->vm_mm); + if (ret) + goto release; + (void)pmdp_huge_clear_flush(vma, haddr, vmf->pmd); + map_anon_folio_pmd(folio, vmf->pmd, vma, haddr); + goto unlock; +release: + folio_put(folio); +unlock: + spin_unlock(vmf->ptl); + mmu_notifier_invalidate_range_end(&range); +out: + return ret; +} + vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf) { const bool unshare = vmf->flags & FAULT_FLAG_UNSHARE; @@ -1802,8 +1837,15 @@ vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf) vmf->ptl = pmd_lockptr(vma->vm_mm, vmf->pmd); VM_BUG_ON_VMA(!vma->anon_vma, vma); - if (is_huge_zero_pmd(orig_pmd)) + if (is_huge_zero_pmd(orig_pmd)) { + vm_fault_t ret = do_huge_zero_wp_pmd(vmf); + + if (!(ret & VM_FAULT_FALLBACK)) + return ret; + + /* Fallback to splitting PMD if THP cannot be allocated */ goto fallback; + } spin_lock(vmf->ptl);