From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D4F1E41C2F0 for ; Mon, 29 Jun 2026 13:12:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782738759; cv=none; b=SYtopTakYjlgWYijSwsKorQw2IFfhJLX98LKdmX+KXQtyFVL2ycN07Ca0uVkH3R1LrxGcEidW8nuHQjQfN394trd+WD6vJ7pAH02UG2tyftA2XIp37ERywTI4XB0Jbk7RSvX4RQpdN6BXh+1nT1qUNOABR3XR+Tv7sqtdwc7GrI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782738759; c=relaxed/simple; bh=vSb4RrapdAWhzNd3r+X62VZHRs4Ti9eUkiG0Gsj8wjo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=lhClbXzgZXpGthmVzWzkf0xgILb54/MNPmW3Z6zmmGBzwMYDjnHrOSLqh3HK1CVc07utebpio8MbsIzQr7G3i+ZyEplfB5fvqBVVcu2pXQjCuMZ8AEzGaKtDcVlJLilqnBx+Yj5m36kmMW/eqB9smV2Pt5v7h5+TCqw/4fPp2Ys= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=uTEJWV7V; arc=none smtp.client-ip=209.85.221.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="uTEJWV7V" Received: by mail-wr1-f73.google.com with SMTP id ffacd0b85a97d-4731a357b0aso767406f8f.2 for ; Mon, 29 Jun 2026 06:12:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1782738756; x=1783343556; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=jdj9C/B8eHaGvKbpCd9yiXjpao1QqOLZ74XGYE6JkIY=; b=uTEJWV7VaNHLXZ/6X8RGQ8AWsIyJD4X/lTh6H3ykZxt7uN7MlWOHgOFdap7Pe7+LC3 mjmyELRbyUNd9NBS50AtCLtMVe0ALTBo8qYm9RBPIWVYD+KN8VgLfbT6XHbbpaEChDlB /F/Jrg4IhwWoHrbv8QJRCuUGcb53RfDKYradOJq1++wjGHpFGRvZCQLLYyz6JXzdissy WDT3U6I/DwqvgeQMJOP1bSdnI2a+ONvi0ARSRUDGVYI7NVTyCj+/UF+5t3cEJ/h3vDgC YeF8DwpTWldbFLyfSX0TWDYxll32TWA6KY5xVGYJ6ew9xiOBAmUt3zL1IjnSne5rn4my tVkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782738756; x=1783343556; 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=jdj9C/B8eHaGvKbpCd9yiXjpao1QqOLZ74XGYE6JkIY=; b=hoXpTbqvCkrSMKp/c4pvdABZ3Sb5bXoyqrATWHuaQ0YYfKcR0klVd9fLj6LMYKnsCt 36+BYBKT4Pf3ZlAOWfQmlyUTnZ9GmLwmlSjtIAHE3Fq2n606NJkkcNmy4ZfXSIqYlJ7J 6Gx84kesvlxhcL1kP+Xj55eVJFVFcqiZO9xCry8yxJw9StZRLi9tcJW90uG2O1ooONwO IAeF3PYh1Fk7SyIHiwuO9lV+DWpH4LpKglj+BvWGkH0yooV4wqYVoeIzCu+KSHnklfyj 4k3N8h//3XVvmNICsgBE0RnKsnoCDD3M/AjaaqWPXRTdQ2wrnM8YVrv/jbhK8mUF3JZa KJig== X-Forwarded-Encrypted: i=1; AFNElJ86PcWybchL28kvchp1i12WiV2Uoh9NFhfnd78Q9bK8UMx8zLZiY+7io3yKJlJ7eduEl/ByihICKPhnGpDnzw==@lists.linux.dev X-Gm-Message-State: AOJu0YzpcNUKl66lD+KNjKuD+8dTOiOOvre0jPMvX36O1WjupKnO9TH6 No7+s4UrvbAA1aqQUQbRkszv8tOFGfSD1q2oizqFPvXkyxhi9qA0f3ri3Xd2Abk+B4sGVkf0s+H NgqURw7IxTBuLzQ== X-Received: from wmnj20.prod.google.com ([2002:a05:600c:754:b0:493:b691:8628]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:8711:b0:493:b549:3bf1 with SMTP id 5b1f17b1804b1-493b5493ff2mr24542445e9.12.1782738755265; Mon, 29 Jun 2026 06:12:35 -0700 (PDT) Date: Mon, 29 Jun 2026 13:12:04 +0000 In-Reply-To: <20260629-alloc-trylock-v3-0-57bef0eadbc2@google.com> Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260629-alloc-trylock-v3-0-57bef0eadbc2@google.com> X-Mailer: b4 0.15.2 Message-ID: <20260629-alloc-trylock-v3-15-57bef0eadbc2@google.com> Subject: [PATCH v3 15/16] mm: replace __GFP_NO_CODETAG with ALLOC_NO_CODETAG From: Brendan Jackman To: Andrew Morton , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Johannes Weiner , Zi Yan , Muchun Song , Oscar Salvador , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Ying Huang , Alistair Popple , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt Cc: "Harry Yoo (Oracle)" , Gregory Price , Johannes Weiner , Alexei Starovoitov , Matthew Wilcox , Hao Ge , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, Brendan Jackman Content-Type: text/plain; charset="utf-8" Now that alloc_pages has an entrypoint that allows passing alloc_flags, we can take advantage of this to start removing GFP flags that are only used for mm-internal stuff. This requires also plumbing the alloc_flags into some more of the allocator code, in particular __alloc_pages[_noprof]() gets an alloc_flags arg to go along with its callees, and we now need to pass those flags deeper into the allocator so they can reach the alloc_tag code. No functional change intended. Signed-off-by: Brendan Jackman --- mm/alloc_tag.c | 22 ++++++---------------- mm/compaction.c | 4 ++-- mm/internal.h | 1 - mm/page_alloc.c | 42 ++++++++++++++++++++++++------------------ mm/page_alloc.h | 17 +++++++++++++++-- mm/page_frag_cache.c | 4 ++-- 6 files changed, 49 insertions(+), 41 deletions(-) diff --git a/mm/alloc_tag.c b/mm/alloc_tag.c index d9be1cf5187d9..a32a94e759b94 100644 --- a/mm/alloc_tag.c +++ b/mm/alloc_tag.c @@ -15,6 +15,8 @@ #include #include +#include "internal.h" + #define ALLOCINFO_FILE_NAME "allocinfo" #define MODULE_ALLOC_TAG_VMAP_SIZE (100000UL * sizeof(struct alloc_tag)) #define SECTION_START(NAME) (CODETAG_SECTION_START_PREFIX NAME) @@ -783,19 +785,6 @@ struct pfn_pool { #define PFN_POOL_SIZE ((PAGE_SIZE - offsetof(struct pfn_pool, pfns)) / \ sizeof(unsigned long)) - -/* - * Skip early PFN recording for a page allocation. Reuses the - * %__GFP_NO_OBJ_EXT bit. Used by __alloc_tag_add_early_pfn() to avoid - * recursion when allocating pages for the early PFN tracking list - * itself. - * - * Codetags of the pages allocated with __GFP_NO_CODETAG should be - * cleared (via clear_page_tag_ref()) before freeing the pages to prevent - * alloc_tag_sub_check() from triggering a warning. - */ -#define __GFP_NO_CODETAG __GFP_NO_OBJ_EXT - static struct pfn_pool *current_pfn_pool __initdata; static void __init __alloc_tag_add_early_pfn(unsigned long pfn) @@ -806,7 +795,8 @@ static void __init __alloc_tag_add_early_pfn(unsigned long pfn) do { pool = READ_ONCE(current_pfn_pool); if (!pool || atomic_read(&pool->count) >= PFN_POOL_SIZE) { - struct page *new_page = alloc_page(__GFP_HIGH | __GFP_NO_CODETAG); + struct page *new_page = __alloc_pages(__GFP_HIGH, 0, numa_mem_id(), + NULL, ALLOC_NO_CODETAG); struct pfn_pool *new; if (!new_page) { @@ -837,7 +827,7 @@ typedef void alloc_tag_add_func(unsigned long pfn); static alloc_tag_add_func __rcu *alloc_tag_add_early_pfn_ptr __refdata = RCU_INITIALIZER(__alloc_tag_add_early_pfn); -void alloc_tag_add_early_pfn(unsigned long pfn, gfp_t gfp_flags) +void alloc_tag_add_early_pfn(unsigned long pfn, unsigned int alloc_flags) { alloc_tag_add_func *alloc_tag_add; @@ -845,7 +835,7 @@ void alloc_tag_add_early_pfn(unsigned long pfn, gfp_t gfp_flags) return; /* Skip allocations for the tracking list itself to avoid recursion. */ - if (gfp_flags & __GFP_NO_CODETAG) + if (alloc_flags & ALLOC_NO_CODETAG) return; rcu_read_lock(); diff --git a/mm/compaction.c b/mm/compaction.c index 7d80735502d9a..4b2318fad4eb5 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -83,7 +83,7 @@ static inline bool is_via_compact_memory(int order) { return false; } static struct page *mark_allocated_noprof(struct page *page, unsigned int order, gfp_t gfp_flags) { - post_alloc_hook(page, order, __GFP_MOVABLE); + post_alloc_hook(page, order, __GFP_MOVABLE, ALLOC_DEFAULT); set_page_refcounted(page); return page; } @@ -1851,7 +1851,7 @@ static struct folio *compaction_alloc_noprof(struct folio *src, unsigned long da } dst = (struct folio *)freepage; - post_alloc_hook(&dst->page, order, __GFP_MOVABLE); + post_alloc_hook(&dst->page, order, __GFP_MOVABLE, ALLOC_DEFAULT); set_page_refcounted(&dst->page); if (order) prep_compound_page(&dst->page, order); diff --git a/mm/internal.h b/mm/internal.h index c22284f04fc9e..369c656c63fa8 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1237,7 +1237,6 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone, enum ttu_flags; struct tlbflush_unmap_batch; - /* * only for MM internal work items which do not depend on * any allocations or locks which might depend on allocations diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 026f33f217036..803b32e5a5e47 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1249,7 +1249,7 @@ void __clear_page_tag_ref(struct page *page) /* Should be called only if mem_alloc_profiling_enabled() */ static noinline void __pgalloc_tag_add(struct page *page, struct task_struct *task, - unsigned int nr, gfp_t gfp_flags) + unsigned int nr, unsigned int alloc_flags) { union pgtag_ref_handle handle; union codetag_ref ref; @@ -1263,17 +1263,17 @@ void __pgalloc_tag_add(struct page *page, struct task_struct *task, * page_ext is not available yet, record the pfn so we can * clear the tag ref later when page_ext is initialized. */ - alloc_tag_add_early_pfn(page_to_pfn(page), gfp_flags); + alloc_tag_add_early_pfn(page_to_pfn(page), alloc_flags); if (task->alloc_tag) alloc_tag_set_inaccurate(task->alloc_tag); } } static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, - unsigned int nr, gfp_t gfp_flags) + unsigned int nr, unsigned int alloc_flags) { if (mem_alloc_profiling_enabled()) - __pgalloc_tag_add(page, task, nr, gfp_flags); + __pgalloc_tag_add(page, task, nr, alloc_flags); } /* Should be called only if mem_alloc_profiling_enabled() */ @@ -1810,7 +1810,7 @@ static inline bool should_skip_init(gfp_t flags) } inline void post_alloc_hook(struct page *page, unsigned int order, - gfp_t gfp_flags) + gfp_t gfp_flags, unsigned int alloc_flags) { const bool zero_tags = gfp_flags & __GFP_ZEROTAGS; bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) && @@ -1861,13 +1861,13 @@ inline void post_alloc_hook(struct page *page, unsigned int order, set_page_owner(page, order, gfp_flags); page_table_check_alloc(page, order); - pgalloc_tag_add(page, current, 1 << order, gfp_flags); + pgalloc_tag_add(page, current, 1 << order, alloc_flags); } static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags, unsigned int alloc_flags) { - post_alloc_hook(page, order, gfp_flags); + post_alloc_hook(page, order, gfp_flags, alloc_flags); if (order && (gfp_flags & __GFP_COMP)) prep_compound_page(page, order); @@ -4791,8 +4791,12 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * The fast path uses conservative alloc_flags to succeed only until * kswapd needs to be woken up, and to avoid the cost of setting up * alloc_flags precisely. So we do that now. + * + * Can't just or alloc_flags if it contains WMARK bits, but those flags + * shouldn't be set in ac->alloc_flags. */ - alloc_flags = alloc_flags_slowpath(gfp_mask, order); + VM_WARN_ON(ac->alloc_flags & ALLOC_WMARK_MASK); + alloc_flags = ac->alloc_flags | alloc_flags_slowpath(gfp_mask, order); /* * We need to recalculate the starting point for the zonelist iterator @@ -4834,7 +4838,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, reserve_flags = __gfp_pfmemalloc_flags(gfp_mask); if (reserve_flags) alloc_flags = alloc_flags_cma(gfp_mask, reserve_flags) | - (alloc_flags & ALLOC_KSWAPD); + ac->alloc_flags | (alloc_flags & ALLOC_KSWAPD); /* * Reset the nodemask and zonelist iterators if memory policies can be @@ -5236,7 +5240,7 @@ unsigned long alloc_pages_bulk_noprof(gfp_t gfp, int preferred_nid, return nr_populated; failed: - page = __alloc_pages_noprof(gfp, 0, preferred_nid, nodemask); + page = __alloc_pages_noprof(gfp, 0, preferred_nid, nodemask, ALLOC_DEFAULT); if (page) page_array[nr_populated++] = page; goto out; @@ -5344,11 +5348,13 @@ struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, { struct page *page; gfp_t alloc_gfp; /* The gfp_t that was actually used for allocation */ - struct alloc_context ac = { }; + struct alloc_context ac = { + .alloc_flags = alloc_flags, + }; unsigned int fastpath_alloc_flags = alloc_flags; /* Other flags could be supported later if needed. */ - if (WARN_ON(alloc_flags & ~ALLOC_NOLOCK)) + if (WARN_ON(alloc_flags & ~(ALLOC_NOLOCK | ALLOC_NO_CODETAG))) return NULL; if (!alloc_order_allowed(gfp, order, alloc_flags)) @@ -5417,12 +5423,12 @@ struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, EXPORT_SYMBOL(__alloc_frozen_pages_noprof); struct page *__alloc_pages_noprof(gfp_t gfp, unsigned int order, - int preferred_nid, nodemask_t *nodemask) + int preferred_nid, nodemask_t *nodemask, unsigned int alloc_flags) { struct page *page; page = __alloc_frozen_pages_noprof(gfp, order, preferred_nid, nodemask, - ALLOC_DEFAULT); + alloc_flags); if (page) set_page_refcounted(page); return page; @@ -5436,7 +5442,7 @@ struct page *alloc_pages_node_noprof(int nid, gfp_t gfp_mask, unsigned int order VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES); warn_if_node_offline(nid, gfp_mask); - return __alloc_pages_noprof(gfp_mask, order, nid, NULL); + return __alloc_pages_noprof(gfp_mask, order, nid, NULL, ALLOC_DEFAULT); } EXPORT_SYMBOL(alloc_pages_node_noprof); @@ -5444,7 +5450,7 @@ struct folio *__folio_alloc_noprof(gfp_t gfp, unsigned int order, int preferred_ nodemask_t *nodemask) { struct page *page = __alloc_pages_noprof(gfp | __GFP_COMP, order, - preferred_nid, nodemask); + preferred_nid, nodemask, ALLOC_DEFAULT); return page_rmappable_folio(page); } EXPORT_SYMBOL(__folio_alloc_noprof); @@ -7126,7 +7132,7 @@ static void split_free_frozen_pages(struct list_head *list, gfp_t gfp_mask) list_for_each_entry_safe(page, next, &list[order], lru) { int i; - post_alloc_hook(page, order, gfp_mask); + post_alloc_hook(page, order, gfp_mask, ALLOC_DEFAULT); if (!order) continue; @@ -7331,7 +7337,7 @@ int alloc_contig_frozen_range_noprof(unsigned long start, unsigned long end, struct page *head = pfn_to_page(start); check_new_pages(head, order); - prep_new_page(head, order, gfp_mask, 0); + prep_new_page(head, order, gfp_mask, ALLOC_DEFAULT); } else { ret = -EINVAL; WARN(true, "PFN range: requested [%lu, %lu), allocated [%lu, %lu)\n", diff --git a/mm/page_alloc.h b/mm/page_alloc.h index 2058cbdca56e7..2614bff6795b0 100644 --- a/mm/page_alloc.h +++ b/mm/page_alloc.h @@ -49,6 +49,16 @@ #define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ #define ALLOC_NOLOCK 0x400 /* Only use spin_trylock in allocation path */ #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ +/* + * Skip early PFN recording for a page allocation. Used by + * __alloc_tag_add_early_pfn() to avoid recursion when allocating pages for the + * early PFN tracking list itself. + * + * Codetags of the pages allocated with __GFP_NO_CODETAG should be + * cleared (via clear_page_tag_ref()) before freeing the pages to prevent + * alloc_tag_sub_check() from triggering a warning. + */ +#define ALLOC_NO_CODETAG 0x1000 /* Flags that allow allocations below the min watermark. */ #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) @@ -84,6 +94,8 @@ struct alloc_context { */ enum zone_type highest_zoneidx; bool spread_dirty_pages; + /* Only flags that are global to the whole allocation go here. */ + unsigned int alloc_flags; }; /* @@ -214,7 +226,8 @@ static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, extern void __free_pages_core(struct page *page, unsigned int order, enum meminit_context context); -void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags); +void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags, + unsigned int alloc_flags); extern bool free_pages_prepare(struct page *page, unsigned int order); extern int user_min_free_kbytes; @@ -245,7 +258,7 @@ struct page *alloc_frozen_pages_nolock_noprof(gfp_t gfp_flags, int nid, unsigned void free_frozen_pages_nolock(struct page *page, unsigned int order); struct page *__alloc_pages_noprof(gfp_t gfp, unsigned int order, int preferred_nid, - nodemask_t *nodemask); + nodemask_t *nodemask, unsigned int alloc_flags); #define __alloc_pages(...) alloc_hooks(__alloc_pages_noprof(__VA_ARGS__)) extern void zone_pcp_reset(struct zone *zone); diff --git a/mm/page_frag_cache.c b/mm/page_frag_cache.c index a1077cef3a791..e63efe78b7d4b 100644 --- a/mm/page_frag_cache.c +++ b/mm/page_frag_cache.c @@ -57,10 +57,10 @@ static struct page *__page_frag_cache_refill(struct page_frag_cache *nc, gfp_mask = (gfp_mask & ~__GFP_DIRECT_RECLAIM) | __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC; page = __alloc_pages(gfp_mask, PAGE_FRAG_CACHE_MAX_ORDER, - numa_mem_id(), NULL); + numa_mem_id(), NULL, ALLOC_DEFAULT); #endif if (unlikely(!page)) { - page = __alloc_pages(gfp, 0, numa_mem_id(), NULL); + page = __alloc_pages(gfp, 0, numa_mem_id(), NULL, ALLOC_DEFAULT); order = 0; } -- 2.54.0