From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E24F47ECDC; Wed, 17 Jun 2026 16:39:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781714365; cv=none; b=eFIWiEV2sn5Ru4t98tQSSd4w1w4+N6wJ47FEcFICDaRiBfDWJpq46Rs+boGvcDL0MbOY5TG/eyjN1eI72dfgaPlWE0ePnD8nAzr2pQd3bKEOH/n74nSwbWDz4P/2qMf/04caqtAG9+QfV7eS6S+fjAfln4osz4rkR1E9ARFJCzg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781714365; c=relaxed/simple; bh=RPAKwPG3kLE2LN7X+vrBn0P+RkV5ZP1HD018N6PU1ns=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ifDKkLpV5MzcWatsQtQ5qgacdiMvEGPSoDjnyH6RF9UgM3fuapDfvDbofejllUYlZwmKmq5uazSLdfJS7xgTZWOn4A45PmrWM/HQgvolIDcVzVCvl8h9WN0PEmSdgnMtea7VbKF/UFJeKIqns3Odk1dfJcRfNZQkAD4Mx5Lx6fY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nmlbaOZe; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nmlbaOZe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CBD271F000E9; Wed, 17 Jun 2026 16:39:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781714361; bh=eLDkg4WxnXGnsAZI8cb873zZ7d7ZuisTrkvapay2URM=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=nmlbaOZewZyXiU0WW4bU4/DKdnYUY6HTFd4ZBsRXPtiSwN3C+4Cx3qSQmYZ2Q/4dx fJOxcQ1w6vTIUN2yOMbvfDlPnXy9RI+A/b+5xAqmRS3oAENHR42thV6Ap12v5AQsNE dHBKFcmUGlhlM/UZymISqvt3JPi5204VfHeHxSNBRiY2pQuWIMnUEeiCO/hqAW3IOn bv6DJz4NZTcpSBnZ4lt6qtXGat+dIWtriC1nMBdqdGlSeQM5UsSJmgQg3WMSI/a/OR jAyDvfxZvUsweFBvVILxFDEyiJxUgj2MoX9bohbMnWvc6PgAYvBRRpdqUOO/+GRgwd w1RBStSaDfPAA== Message-ID: <2399b3ad-4eac-4a14-94c3-27e9f07972a1@kernel.org> Date: Wed, 17 Jun 2026 18:39:14 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/page_alloc: unify __alloc_frozen_pages[_nolock]_noprof() Content-Language: en-US To: Brendan Jackman , Andrew Morton , 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 , Alexei Starovoitov Cc: "Harry Yoo (Oracle)" , Gregory Price , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev References: <20260617-alloc-trylock-v1-1-83fd7858832e@google.com> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSNWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBrZXJuZWwub3JnPsLBsAQTAQoAWhYhBKlA1DSZLC6OmRA9UCJPp+fM gqZkBQJqFFy6GxSAAAAAAAQADm1hbnUyLDIuNSsxLjEyLDIsMgIbAwUJGtCBUAULCQgHAwUV CgkICwUWAgMBAAIeBQIXgAAKCRAiT6fnzIKmZJIUEADFx/tREzUImHrEwVHeSvDFmA7tJysI UVrlvrM09E7GIuzphzv7jYmo8n3ANpCczLEVr4G0syYQdTigaZgv3+FQDIIzhKih1IHhu1Ei XHlywNWKnQxxQEUNi5Mwx43wQz5XVw9F1A7gtKBKNtfogO511hAbrzagrYajyQacEJ/+sfhZ 9Da8ltHIXD8pcYaHUfQgEusCgmEd9+KrUwrTbckFKmYq5chuE6yJ4J0EmWknL096jIE6CnzF FRslQ3B1UKDjxVsm1ZHfir5NeWszLkTvGFsddFaWTgh8UycESG6VQzKXjjewXu2pG7YQYRpj QKm1W5X2TkwWkXRBZTmfmbhxIUMh3+zf5wQ463rSmDN/8v81tdqBtAW6rH/kzg1GvkaTHXn0 507yEHFzBksk2viAuIxxr7km8+/KARYLIdGtx30EG8cKzAUZOK6WqxtNCsXUJNrVE8CWrCaD icoNu7Fs1c5hmPHdSTnU48ce67449DdnO4neLSNhRiGlMHJgfJUmgrxu/hcYeOZ3haWmEQ2w uW1Mh01OHi8QZHCEyAbABrPs9GUgccc/4eYXX9hIgxfSkYzn8f+8NuIFPWl/0uTvjgqU29FQ SbzOLxHq9439Ox40G5mS5eZXRGxITYR+6TXvRGI6P/264jvflnr/pDGUttaikU+0W+1uxgKH cmYbEc7ATQRbGTU1AQgAn0H6UrFiWcovkh6EXVcl+SeqyO6JHOPm+e9Wu0Vw+VIUvXZVUVVQ La1PQDUi6j00ChlcR66g9/V0sPIcSutacPKfdKYOBvzd4rlhL8rfrdEsQw5ApZxrA8kYZVMh FmBRKAa6wos25moTlMKpCWzTH84+WO5+ziCTsTUZASAToz3RdunTD+vQcHj0GqNTPAHK63sf bAB2I0BslZkXkY1RLb/YhuA6E7JyEd2pilZOrIuBGl/5q2qSakgnAVFWFBR/DO27JuAksYnq +aH8vI0xGvwn75KqSk4UzAkDzWSmO4ZHuahKtQgZNsMYV+PGayRBX9b9zbldzopoLBdqHc4n jQARAQABwsF8BBgBCgAmAhsMFiEEqUDUNJksLo6ZED1QIk+n58yCpmQFAmfIHFQFCRYU6J8A CgkQIk+n58yCpmS2PA//bqN1LfcotmArgElsa+0EGZSQlYgK48pm8WAeTXTngudP9IJ4SuKY HR5RNjHcBeqN+Me0zxRqYzRb8nGanHEkDyf4Im8DQM8d6vbyU+FcPmG4skud4kgS1zMHnlVd SXfSIwKC/hKgdHG8aBV7545Lz9X6Iohea+94wneD0aw/hqF+QWewGZhWJriWAZtvEkzNjQOi 4U9F/trLten/x7bpphDSnDMKJtITbtzATT1Dq7o7VpIUK1nCTQALMuMjKCdi8OdU/+V+R3O4 0PXWvX8qrvqYapVbZ+9KqT74FsuB0Ya9uXwgBF2Q6cRuETZk5vqaqKxzqoQZCO8AOz/58j6O 2RHNy/mZEN+7tJ5Tsq42zVJ4jxsT8b9YplavCMsnBgDeRWhcbYhCyttoL7nYISyWg4kQYZ/P wIV3OuNv2f8iKYsxNsRuClOAF82+gvqOy1/1pprFjy8uo2pkoOrb63aOP3vO5VHnRKgra6dq NcaZ+c6J4H+nEJGi2SkHAUJz5oBzuThvPudLvPA/SK8sKoM01IRxSihev/S/5WLazXB1PGem OCbvzC1IjWJJraxiDJ5IygokapUa2RP7+WBR22skQ3SSl6G107QgWKSyTOGWEaRmV53vxQLV jXuCmzSSasTL60zq5yGrT4/DYQVSNEUiUbG4pYekxJujNeEDkUlky0Y= In-Reply-To: <20260617-alloc-trylock-v1-1-83fd7858832e@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit +Cc Alexei On 6/17/26 17:29, Brendan Jackman wrote: > Currently the core allocator code is controlled by ALLOC_NOLOCK, but the It's not, it's ALLOC_TRYLOCK! Thanks for proving that we need to rename it to ALLOC_NOLOCK: https://lore.kernel.org/all/DJ9QPTO2WXNB.10E88ZHWRDHB0@gmail.com/ So you just won the job to do the rename :) I think it should be done before this patch, so that the new usages and other _trylock names introduced here can be done as _nolock outright. > main entry point function is significantly different from the normal > __alloc_frozen_pages_nolock(), this is tiring when reading the code. > > Plumb the ALLOC_NOLOCK control one layer up in the call stack: create > an alloc_flags argument to __alloc_frozen_pages_nolock() (which is only > exposed to mm/) and then turn the nolock variant into a thin wrapper > that just sets that flag (as well as handling NUMA_NO_NODE, similar to > how some of the wrappers in gfp.h do). > > Rationale that this doesn't change anything: > > 1. Simple bits: A bunch of the nolock-specific handling is just moved to > the new alloc_order_allowed(), alloc_trylock_allowed() and > gfp_trylock. > > 2. __alloc_frozen_pages_noprof() has some extra logic that wasn't > previously in the nolock variant: > > a. Application of gfp_allowed_mask; this only affects early boot, and > only flags that affect the slowpath get changed here. > > b. Application of current_gfp_context() - also only affects the > slowpath > > 3. The slowpath itself: this is now just explicitly skipped under > !ALLOC_TRYLOCK. I'll have to ponder it more closely. > Ulterior motive: adding an alloc_flags arg to the allocator's > mm-internal entrypoint can later be used to do more allocation > customisation without needing to create new GFP flags. Ack. > No functional change intended. > > Signed-off-by: Brendan Jackman Besides the need to ponder unintended effects, mostly LGTM. Just not a fan of the hardcoded '0' passed at various places. In the slab variant of this (the thread I've linked above) I went with SLAB_ALLOC_DEFAULT, so you can do e.g. ALLOC_DEFAULT here? > --- > mm/hugetlb.c | 2 +- > mm/internal.h | 4 +- > mm/mempolicy.c | 8 +-- > mm/page_alloc.c | 175 +++++++++++++++++++++++++++++--------------------------- > mm/slub.c | 4 +- > 5 files changed, 99 insertions(+), 94 deletions(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 571212b80835e..619f6307dc98d 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1806,7 +1806,7 @@ static struct folio *alloc_buddy_frozen_folio(int order, gfp_t gfp_mask, > if (alloc_try_hard) > gfp_mask |= __GFP_RETRY_MAYFAIL; > > - folio = (struct folio *)__alloc_frozen_pages(gfp_mask, order, nid, nmask); > + folio = (struct folio *)__alloc_frozen_pages(gfp_mask, order, nid, nmask, 0); > > /* > * If we did not specify __GFP_RETRY_MAYFAIL, but still got a > diff --git a/mm/internal.h b/mm/internal.h > index 181e79f1d6a20..1043eb833836c 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -913,7 +913,7 @@ extern bool free_pages_prepare(struct page *page, unsigned int order); > extern int user_min_free_kbytes; > > struct page *__alloc_frozen_pages_noprof(gfp_t, unsigned int order, int nid, > - nodemask_t *); > + nodemask_t *, unsigned int alloc_flags); > #define __alloc_frozen_pages(...) \ > alloc_hooks(__alloc_frozen_pages_noprof(__VA_ARGS__)) > void free_frozen_pages(struct page *page, unsigned int order); > @@ -924,7 +924,7 @@ struct page *alloc_frozen_pages_noprof(gfp_t, unsigned int order); > #else > static inline struct page *alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order) > { > - return __alloc_frozen_pages_noprof(gfp, order, numa_node_id(), NULL); > + return __alloc_frozen_pages_noprof(gfp, order, numa_node_id(), NULL, 0); > } > #endif > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 36699fabd3c22..dccff90682035 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -2425,9 +2425,9 @@ static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order, > */ > preferred_gfp = gfp | __GFP_NOWARN; > preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); > - page = __alloc_frozen_pages_noprof(preferred_gfp, order, nid, nodemask); > + page = __alloc_frozen_pages_noprof(preferred_gfp, order, nid, nodemask, 0); > if (!page) > - page = __alloc_frozen_pages_noprof(gfp, order, nid, NULL); > + page = __alloc_frozen_pages_noprof(gfp, order, nid, NULL, 0); > > return page; > } > @@ -2475,7 +2475,7 @@ static struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order, > */ > page = __alloc_frozen_pages_noprof( > gfp | __GFP_THISNODE | __GFP_NORETRY, order, > - nid, NULL); > + nid, NULL, 0); > if (page || !(gfp & __GFP_DIRECT_RECLAIM)) > return page; > /* > @@ -2487,7 +2487,7 @@ static struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order, > } > } > > - page = __alloc_frozen_pages_noprof(gfp, order, nid, nodemask); > + page = __alloc_frozen_pages_noprof(gfp, order, nid, nodemask, 0); > > if (unlikely(pol->mode == MPOL_INTERLEAVE || > pol->mode == MPOL_WEIGHTED_INTERLEAVE) && page) { > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 0111cdbdb5321..fc4d07bbf44b5 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5253,24 +5253,98 @@ void free_pages_bulk(struct page **page_array, unsigned long nr_pages) > } > } > > -/* > - * This is the 'heart' of the zoned buddy allocator. > - */ > -struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, > - int preferred_nid, nodemask_t *nodemask) > +static inline bool alloc_order_allowed(gfp_t gfp, unsigned int order, > + unsigned int alloc_flags) > { > - struct page *page; > - unsigned int alloc_flags = ALLOC_WMARK_LOW; > - gfp_t alloc_gfp; /* The gfp_t that was actually used for allocation */ > - struct alloc_context ac = { }; > + > + if (alloc_flags & ALLOC_TRYLOCK) > + return pcp_allowed_order(order); > > /* > * There are several places where we assume that the order value is sane > * so bail out early if the request is out of bound. > */ > - if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp)) > + return !(WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp)); > +} > + > +static inline bool alloc_trylock_allowed(void) > +{ > + /* > + * In PREEMPT_RT spin_trylock() will call raw_spin_lock() which is > + * unsafe in NMI. If spin_trylock() is called from hard IRQ the current > + * task may be waiting for one rt_spin_lock, but rt_spin_trylock() will > + * mark the task as the owner of another rt_spin_lock which will > + * confuse PI logic, so return immediately if called from hard IRQ or > + * NMI. > + * > + * Note, irqs_disabled() case is ok. This function can be called > + * from raw_spin_lock_irqsave region. > + */ > + if (IS_ENABLED(CONFIG_PREEMPT_RT) && (in_nmi() || in_hardirq())) > + return false; > + > + /* On UP, spin_trylock() always succeeds even when it is locked */ > + if (!IS_ENABLED(CONFIG_SMP) && in_nmi()) > + return false; > + > + /* Bailout, since _deferred_grow_zone() needs to take a lock */ > + if (deferred_pages_enabled()) > + return false; > + > + return true; > +} > + > +/* > + * GFP flags to set for ALLOC_TRYLOCK i.e. alloc_pages_nolock(). > + * > + * Do not specify __GFP_DIRECT_RECLAIM, since direct claim is not allowed. > + * Do not specify __GFP_KSWAPD_RECLAIM either, since wake up of kswapd > + * is not safe in arbitrary context. > + * > + * These two are the conditions for gfpflags_allow_spinning() being true. > + * > + * Specify __GFP_NOWARN since failing alloc_pages_nolock() is not a reason > + * to warn. Also warn would trigger printk() which is unsafe from > + * various contexts. We cannot use printk_deferred_enter() to mitigate, > + * since the running context is unknown. > + * > + * Specify __GFP_ZERO to make sure that call to kmsan_alloc_page() below > + * is safe in any context. Also zeroing the page is mandatory for > + * BPF use cases. > + * > + * Though __GFP_NOMEMALLOC is not checked in the code path below, > + * specify it here to highlight that alloc_pages_nolock() > + * doesn't want to deplete reserves. > + */ > +static const gfp_t gfp_trylock = __GFP_NOWARN | __GFP_ZERO | __GFP_NOMEMALLOC | > + __GFP_COMP; > + > +/* > + * This is the 'heart' of the zoned buddy allocator. > + */ > +struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, > + int preferred_nid, nodemask_t *nodemask, unsigned int alloc_flags) > +{ > + struct page *page; > + gfp_t alloc_gfp; /* The gfp_t that was actually used for allocation */ > + struct alloc_context ac = { }; > + > + /* Other flags could be supported later if needed. */ > + if (WARN_ON(alloc_flags & ~ALLOC_TRYLOCK)) > return NULL; > > + if (!alloc_order_allowed(gfp, order, alloc_flags)) > + return NULL; > + > + if (alloc_flags & ALLOC_TRYLOCK) { > + VM_WARN_ON_ONCE(gfp & ~__GFP_ACCOUNT); > + if (!alloc_trylock_allowed()) > + return NULL; > + gfp |= gfp_trylock; > + } else { > + alloc_flags |= ALLOC_WMARK_LOW; > + } > + > gfp &= gfp_allowed_mask; > /* > * Apply scoped allocation constraints. This is mainly about GFP_NOFS > @@ -5291,9 +5365,9 @@ struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, > */ > alloc_flags |= alloc_flags_nofragment(zonelist_zone(ac.preferred_zoneref), gfp); > > - /* First allocation attempt */ > + /* First allocation attempt (or, for trylock, only attempt) */ > page = get_page_from_freelist(alloc_gfp, order, alloc_flags, &ac); > - if (likely(page)) > + if (likely(page) || (alloc_flags & ALLOC_TRYLOCK)) > goto out; > > alloc_gfp = gfp; > @@ -5310,7 +5384,8 @@ struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, > out: > if (memcg_kmem_online() && (gfp & __GFP_ACCOUNT) && page && > unlikely(__memcg_kmem_charge_page(page, gfp, order) != 0)) { > - free_frozen_pages(page, order); > + __free_frozen_pages(page, order, > + alloc_flags & ALLOC_TRYLOCK ? FPI_TRYLOCK : 0); > page = NULL; > } > > @@ -5326,7 +5401,7 @@ struct page *__alloc_pages_noprof(gfp_t gfp, unsigned int order, > { > struct page *page; > > - page = __alloc_frozen_pages_noprof(gfp, order, preferred_nid, nodemask); > + page = __alloc_frozen_pages_noprof(gfp, order, preferred_nid, nodemask, 0); > if (page) > set_page_refcounted(page); > return page; > @@ -7856,80 +7931,10 @@ static bool __free_unaccepted(struct page *page) > > struct page *alloc_frozen_pages_nolock_noprof(gfp_t gfp_flags, int nid, unsigned int order) > { > - /* > - * Do not specify __GFP_DIRECT_RECLAIM, since direct claim is not allowed. > - * Do not specify __GFP_KSWAPD_RECLAIM either, since wake up of kswapd > - * is not safe in arbitrary context. > - * > - * These two are the conditions for gfpflags_allow_spinning() being true. > - * > - * Specify __GFP_NOWARN since failing alloc_pages_nolock() is not a reason > - * to warn. Also warn would trigger printk() which is unsafe from > - * various contexts. We cannot use printk_deferred_enter() to mitigate, > - * since the running context is unknown. > - * > - * Specify __GFP_ZERO to make sure that call to kmsan_alloc_page() below > - * is safe in any context. Also zeroing the page is mandatory for > - * BPF use cases. > - * > - * Though __GFP_NOMEMALLOC is not checked in the code path below, > - * specify it here to highlight that alloc_pages_nolock() > - * doesn't want to deplete reserves. > - */ > - gfp_t alloc_gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_NOMEMALLOC | __GFP_COMP > - | gfp_flags; > - unsigned int alloc_flags = ALLOC_TRYLOCK; > - struct alloc_context ac = { }; > - struct page *page; > - > - VM_WARN_ON_ONCE(gfp_flags & ~__GFP_ACCOUNT); > - /* > - * In PREEMPT_RT spin_trylock() will call raw_spin_lock() which is > - * unsafe in NMI. If spin_trylock() is called from hard IRQ the current > - * task may be waiting for one rt_spin_lock, but rt_spin_trylock() will > - * mark the task as the owner of another rt_spin_lock which will > - * confuse PI logic, so return immediately if called from hard IRQ or > - * NMI. > - * > - * Note, irqs_disabled() case is ok. This function can be called > - * from raw_spin_lock_irqsave region. > - */ > - if (IS_ENABLED(CONFIG_PREEMPT_RT) && (in_nmi() || in_hardirq())) > - return NULL; > - > - /* On UP, spin_trylock() always succeeds even when it is locked */ > - if (!IS_ENABLED(CONFIG_SMP) && in_nmi()) > - return NULL; > - > - if (!pcp_allowed_order(order)) > - return NULL; > - > - /* Bailout, since _deferred_grow_zone() needs to take a lock */ > - if (deferred_pages_enabled()) > - return NULL; > - > if (nid == NUMA_NO_NODE) > nid = numa_node_id(); > > - prepare_alloc_pages(alloc_gfp, order, nid, NULL, &ac, > - &alloc_gfp, &alloc_flags); > - > - /* > - * Best effort allocation from percpu free list. > - * If it's empty attempt to spin_trylock zone->lock. > - */ > - page = get_page_from_freelist(alloc_gfp, order, alloc_flags, &ac); > - > - /* Unlike regular alloc_pages() there is no __alloc_pages_slowpath(). */ > - > - if (memcg_kmem_online() && page && (gfp_flags & __GFP_ACCOUNT) && > - unlikely(__memcg_kmem_charge_page(page, alloc_gfp, order) != 0)) { > - __free_frozen_pages(page, order, FPI_TRYLOCK); > - page = NULL; > - } > - trace_mm_page_alloc(page, order, alloc_gfp, ac.migratetype); > - kmsan_alloc_page(page, order, alloc_gfp); > - return page; > + return __alloc_frozen_pages_noprof(gfp_flags, order, nid, NULL, ALLOC_TRYLOCK); > } > /** > * alloc_pages_nolock - opportunistic reentrant allocation from any context > diff --git a/mm/slub.c b/mm/slub.c > index a2bf3756ca7d0..b9fb66071bd07 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -3275,7 +3275,7 @@ static inline struct slab *alloc_slab_page(gfp_t flags, int node, > else if (node == NUMA_NO_NODE) > page = alloc_frozen_pages(flags, order); > else > - page = __alloc_frozen_pages(flags, order, node, NULL); > + page = __alloc_frozen_pages(flags, order, node, NULL, 0); > > if (!page) > return NULL; > @@ -5236,7 +5236,7 @@ static void *___kmalloc_large_node(size_t size, gfp_t flags, int node) > if (node == NUMA_NO_NODE) > page = alloc_frozen_pages_noprof(flags, order); > else > - page = __alloc_frozen_pages_noprof(flags, order, node, NULL); > + page = __alloc_frozen_pages_noprof(flags, order, node, NULL, 0); > > if (page) { > ptr = page_address(page); > > --- > base-commit: 1111012ec6508a38a39f8d20c213c8c9cf3c96c0 > change-id: 20260617-alloc-trylock-14ad37dab337 > > Best regards, > -- > Brendan Jackman >