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AJvYcCVVD+8n1Wf2oztbU5SeAKpvruc0c/axYWPlmv8rA+XJ/0ftEjWWfJ4yRLJjQ1/D/JwDcw6SWR0DXQ==@kvack.org X-Gm-Message-State: AOJu0YxXzQI4okoto+4lPuZHu47HIrVgHaXFzz52Lx//rk60fhiI1VRP w+HTm5qy/M9lrs1jGgSB9s1HkFfZc06dNxaQZkhxUcH5ykA2FppW90XjSTV0jXZ0bnIpPQ== X-Google-Smtp-Source: AGHT+IF0hEN8V7uU06C9tElOiOiDXvl7WJ62royjKbG+oprlqtroJ24zLedDhZAejMw2Fg4HCqLgipPv X-Received: from pfej4.prod.google.com ([2002:aa7:8d04:0:b0:725:c7de:e052]) (user=fvdl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:4615:b0:72d:35ed:214b with SMTP id d2e1a72fcca58-7305d515e41mr566746b3a.24.1738867920500; Thu, 06 Feb 2025 10:52:00 -0800 (PST) Date: Thu, 6 Feb 2025 18:51:07 +0000 In-Reply-To: <20250206185109.1210657-1-fvdl@google.com> Mime-Version: 1.0 References: <20250206185109.1210657-1-fvdl@google.com> X-Mailer: git-send-email 2.48.1.502.g6dc24dfdaf-goog Message-ID: <20250206185109.1210657-28-fvdl@google.com> Subject: [PATCH v3 27/28] mm/hugetlb: enable bootmem allocation from CMA areas From: Frank van der Linden To: akpm@linux-foundation.org, muchun.song@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: yuzhao@google.com, usamaarif642@gmail.com, joao.m.martins@oracle.com, roman.gushchin@linux.dev, Frank van der Linden , Madhavan Srinivasan , Michael Ellerman , linuxppc-dev@lists.ozlabs.org X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 92902C0004 X-Stat-Signature: 44owc1t7q38axaa8gp16oy36qyemdynf X-HE-Tag: 1738867921-963032 X-HE-Meta: U2FsdGVkX1+NSrNTy7XECL3VzyxcSdjqS7HJw3wCvhMHP4g7dp4kpHNl8Nt0w/prCSns30E0MyqZLng4aUZIAK33J+0oPGnSDMDZGp19EqeqeyR8HlJaO0nShJEztCelpIbc/w0+odq7p8N2JD/+ReDjm8rrZ8URC/UkfD9r0QU9Ximhnwd1xDtBOAJntIKE9OQ7bnFmAa08V/PfHAJz8faP2BIDPlPzpNfRzh8p7V22NCQeRTvpCtYHiJSP4J2RWCcYZ+zqe2ugz/GBtj1bNsMiNyb87pO6VIyOxF3qw6sHxhHv9QoQzTHxyAULImIm4j4s3pAQNAQempXCMPRY6rmCi+LI1hE7qdrmnPDLsA9v8QonPAQPNYX/QbnaZqCeaPK49MfSWi6wI7JR5YUuKvcSyeh9mmmVQTmL0IWBuxcBEIhWxQysBF1+5EPgRwL8+Mg/tfS2U7p2B3kOEgBZ3jg2pQ3lSd8gRhKpZXXAAOKfj7gtgw6MCl9g9dwTNqWMh6eAVdjNaySBlKzTDlfDsrnNiI5Uq3jUXutNfGZxjKb5lj06GBNKTjONlKCC+Df9ROeo3IY/tlXJ4Rp6aWgwvtJ5PyehSn2e82OWxLtljgpdSUWW9BbAMutBMqqkbskZkcdMJ4pjN5JIkrBeEJi1QNb0wWAWH57J/g22vuPgK66KabRHJ8fjiNrmSLJf0UUCQMXqDk9bRcIBhSx2b8f0AOLD60hLp+UzVyFggudjL/IYc0HgAuIqZidZHr4qItpmNo1hZwVn1PivQCx+VgnHCWScFg50bce5GkR+9+j+oGVV+mJZpru0PPfYcJKZOxqKbJuQK+Hc+v4BlossUnJbwfOILy9DQMWCZQqCHSimlTAJuO4q156kpdz+7CpDXiwm+73ggmPyWpIBuQHd+UolWYcucTfONE1utpMcQ0U/aY4TDRykbifaDT9spCPbRxsFJLMqBm1F2z6S1Q5hd3s W1l1gZIJ 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 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: If hugetlb_cma_only is enabled, we know that hugetlb pages can only be allocated from CMA. Now that there is an interface to do early reservations from a CMA area (returning memblock memory), it can be used to allocate hugetlb pages from CMA. This also allows for doing pre-HVO on these pages (if enabled). Make sure to initialize the page structures and associated data correctly. Create a flag to signal that a hugetlb page has been allocated from CMA to make things a little easier. Some configurations of powerpc have a special hugetlb bootmem allocator, so introduce a boolean arch_specific_huge_bootmem_alloc that returns true if such an allocator is present. In that case, CMA bootmem allocations can't be used, so check that function before trying. Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Frank van der Linden --- arch/powerpc/include/asm/book3s/64/hugetlb.h | 6 + include/linux/hugetlb.h | 17 +++ mm/hugetlb.c | 121 ++++++++++++++----- 3 files changed, 113 insertions(+), 31 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h index f0bba9c5f9c3..bb786694dd26 100644 --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h @@ -94,4 +94,10 @@ static inline int check_and_get_huge_psize(int shift) return mmu_psize; } +#define arch_has_huge_bootmem_alloc arch_has_huge_bootmem_alloc + +static inline bool arch_has_huge_bootmem_alloc(void) +{ + return (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled()); +} #endif diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 2512463bca49..6c6546b54934 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -591,6 +591,7 @@ enum hugetlb_page_flags { HPG_freed, HPG_vmemmap_optimized, HPG_raw_hwp_unreliable, + HPG_cma, __NR_HPAGEFLAGS, }; @@ -650,6 +651,7 @@ HPAGEFLAG(Temporary, temporary) HPAGEFLAG(Freed, freed) HPAGEFLAG(VmemmapOptimized, vmemmap_optimized) HPAGEFLAG(RawHwpUnreliable, raw_hwp_unreliable) +HPAGEFLAG(Cma, cma) #ifdef CONFIG_HUGETLB_PAGE @@ -678,14 +680,18 @@ struct hstate { char name[HSTATE_NAME_LEN]; }; +struct cma; + struct huge_bootmem_page { struct list_head list; struct hstate *hstate; unsigned long flags; + struct cma *cma; }; #define HUGE_BOOTMEM_HVO 0x0001 #define HUGE_BOOTMEM_ZONES_VALID 0x0002 +#define HUGE_BOOTMEM_CMA 0x0004 bool hugetlb_bootmem_page_zones_valid(int nid, struct huge_bootmem_page *m); @@ -823,6 +829,17 @@ static inline pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, } #endif +#ifndef arch_has_huge_bootmem_alloc +/* + * Some architectures do their own bootmem allocation, so they can't use + * early CMA allocation. + */ +static inline bool arch_has_huge_bootmem_alloc(void) +{ + return false; +} +#endif + static inline struct hstate *folio_hstate(struct folio *folio) { VM_BUG_ON_FOLIO(!folio_test_hugetlb(folio), folio); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 24a06d6d3617..737ffd223d45 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -131,8 +131,10 @@ static void hugetlb_free_folio(struct folio *folio) #ifdef CONFIG_CMA int nid = folio_nid(folio); - if (cma_free_folio(hugetlb_cma[nid], folio)) + if (folio_test_hugetlb_cma(folio)) { + WARN_ON_ONCE(!cma_free_folio(hugetlb_cma[nid], folio)); return; + } #endif folio_put(folio); } @@ -1508,6 +1510,9 @@ static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask, break; } } + + if (folio) + folio_set_hugetlb_cma(folio); } #endif if (!folio) { @@ -3174,6 +3179,53 @@ struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, return ERR_PTR(-ENOSPC); } +static bool __init hugetlb_early_cma(struct hstate *h) +{ + if (arch_has_huge_bootmem_alloc()) + return false; + + return (hstate_is_gigantic(h) && hugetlb_cma_only); +} + +static __init void *alloc_bootmem(struct hstate *h, int nid) +{ + struct huge_bootmem_page *m; + unsigned long flags; + struct cma *cma; + +#ifdef CONFIG_CMA + if (hugetlb_early_cma(h)) { + flags = HUGE_BOOTMEM_CMA; + cma = hugetlb_cma[nid]; + m = cma_reserve_early(cma, huge_page_size(h)); + } else +#endif + { + flags = 0; + cma = NULL; + m = memblock_alloc_try_nid_raw(huge_page_size(h), + huge_page_size(h), 0, MEMBLOCK_ALLOC_ACCESSIBLE, nid); + } + + if (m) { + /* + * Use the beginning of the huge page to store the + * huge_bootmem_page struct (until gather_bootmem + * puts them into the mem_map). + * + * Put them into a private list first because mem_map + * is not up yet. + */ + INIT_LIST_HEAD(&m->list); + list_add(&m->list, &huge_boot_pages[nid]); + m->hstate = h; + m->flags = flags; + m->cma = cma; + } + + return m; +} + int alloc_bootmem_huge_page(struct hstate *h, int nid) __attribute__ ((weak, alias("__alloc_bootmem_huge_page"))); int __alloc_bootmem_huge_page(struct hstate *h, int nid) @@ -3183,17 +3235,14 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) /* do node specific alloc */ if (nid != NUMA_NO_NODE) { - m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h), - 0, MEMBLOCK_ALLOC_ACCESSIBLE, nid); + m = alloc_bootmem(h, node); if (!m) return 0; goto found; } /* allocate from next node when distributing huge pages */ for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, &node_states[N_ONLINE]) { - m = memblock_alloc_try_nid_raw( - huge_page_size(h), huge_page_size(h), - 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); + m = alloc_bootmem(h, node); if (m) break; } @@ -3202,7 +3251,6 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) return 0; found: - /* * Only initialize the head struct page in memmap_init_reserved_pages, * rest of the struct pages will be initialized by the HugeTLB @@ -3212,18 +3260,6 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) */ memblock_reserved_mark_noinit(virt_to_phys((void *)m + PAGE_SIZE), huge_page_size(h) - PAGE_SIZE); - /* - * Use the beginning of the huge page to store the - * huge_bootmem_page struct (until gather_bootmem - * puts them into the mem_map). - * - * Put them into a private list first because mem_map - * is not up yet. - */ - INIT_LIST_HEAD(&m->list); - list_add(&m->list, &huge_boot_pages[node]); - m->hstate = h; - m->flags = 0; return 1; } @@ -3264,13 +3300,25 @@ static void __init hugetlb_folio_init_vmemmap(struct folio *folio, prep_compound_head((struct page *)folio, huge_page_order(h)); } +static bool __init hugetlb_bootmem_page_prehvo(struct huge_bootmem_page *m) +{ + return m->flags & HUGE_BOOTMEM_HVO; +} + +static bool __init hugetlb_bootmem_page_earlycma(struct huge_bootmem_page *m) +{ + return m->flags & HUGE_BOOTMEM_CMA; +} + /* * memblock-allocated pageblocks might not have the migrate type set * if marked with the 'noinit' flag. Set it to the default (MIGRATE_MOVABLE) - * here. + * here, or MIGRATE_CMA if this was a page allocated through an early CMA + * reservation. * - * Note that this will not write the page struct, it is ok (and necessary) - * to do this on vmemmap optimized folios. + * In case of vmemmap optimized folios, the tail vmemmap pages are mapped + * read-only, but that's ok - for sparse vmemmap this does not write to + * the page structure. */ static void __init hugetlb_bootmem_init_migratetype(struct folio *folio, struct hstate *h) @@ -3279,9 +3327,13 @@ static void __init hugetlb_bootmem_init_migratetype(struct folio *folio, WARN_ON_ONCE(!pageblock_aligned(folio_pfn(folio))); - for (i = 0; i < nr_pages; i += pageblock_nr_pages) - set_pageblock_migratetype(folio_page(folio, i), + for (i = 0; i < nr_pages; i += pageblock_nr_pages) { + if (folio_test_hugetlb_cma(folio)) + init_cma_pageblock(folio_page(folio, i)); + else + set_pageblock_migratetype(folio_page(folio, i), MIGRATE_MOVABLE); + } } static void __init prep_and_add_bootmem_folios(struct hstate *h, @@ -3327,10 +3379,16 @@ bool __init hugetlb_bootmem_page_zones_valid(int nid, return true; } + if (hugetlb_bootmem_page_earlycma(m)) { + valid = cma_validate_zones(m->cma); + goto out; + } + start_pfn = virt_to_phys(m) >> PAGE_SHIFT; valid = !pfn_range_intersects_zones(nid, start_pfn, pages_per_huge_page(m->hstate)); +out: if (!valid) hstate_boot_nrinvalid[hstate_index(m->hstate)]++; @@ -3359,11 +3417,6 @@ static void __init hugetlb_bootmem_free_invalid_page(int nid, struct page *page, } } -static bool __init hugetlb_bootmem_page_prehvo(struct huge_bootmem_page *m) -{ - return (m->flags & HUGE_BOOTMEM_HVO); -} - /* * Put bootmem huge pages into the standard lists after mem_map is up. * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. @@ -3413,6 +3466,9 @@ static void __init gather_bootmem_prealloc_node(unsigned long nid) */ folio_set_hugetlb_vmemmap_optimized(folio); + if (hugetlb_bootmem_page_earlycma(m)) + folio_set_hugetlb_cma(folio); + list_add(&folio->lru, &folio_list); /* @@ -3605,8 +3661,11 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) { unsigned long allocated; - /* skip gigantic hugepages allocation if hugetlb_cma enabled */ - if (hstate_is_gigantic(h) && hugetlb_cma_size) { + /* + * Skip gigantic hugepages allocation if early CMA + * reservations are not available. + */ + if (hstate_is_gigantic(h) && hugetlb_cma_size && !hugetlb_early_cma(h)) { pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n"); return; }