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 6C1B131D372; Fri, 10 Jul 2026 12:40:29 +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=1783687230; cv=none; b=dMoU7PWESfY5T3TqeV9IqXu1Iy3r02VINAaBTgHlMuZLy9+5KeQA/aB79tchwEomyU0/cinCoKmBqvks44aevVzclSQO7Utq7m9X6HHH/bygMcSqAfJITjUpFScxWhR2pIT2rXDTQvC108u7JGCcFvZPJmr4E9ajDTKPv1PVQQA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783687230; c=relaxed/simple; bh=j4wm4qLnsqIKEigJUA7CAnblpI+Gb/4kFgFuLYNVW+g=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=KoPd/y9oIj6e4mXBn4TQsJBAh7WcJ/btYOxvi3+P+WPjHGsZ2zxM1tdc/ajPi67TFHwd2g5rqo+qo9m3skIZX2+lknwqTbTFD/rzLKrG+E1CI1ho1XTDhCmITFynfG44gzC++hZ5s6r6q5R39sbwgPneWD+3ftYnGMqxIYxUSRY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QCF4e1f7; 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="QCF4e1f7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2ED731F000E9; Fri, 10 Jul 2026 12:40:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783687229; bh=Tng6ULGnh9Em64xwRpMVoclTAzrdwj4WFKuUCJoYag4=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=QCF4e1f7E6b/KOcYr84Em8IiMgqopMFhVRtaoOghoFn8cPYxRll20EGedByzpYxb/ S/dRvwP6TeA4UwVrzkkJNcRlREIOtYGufgRPJR9TQV4eQzvEzQ1a2ObfG68PN4lhTM 0jAZ4Q8sSuF33CSJdpHE+PDTnxLI+zJdne7EVcALYz1DNNYdffNan+CsZqyxlmh/NQ DFoj0H9dFfnUmfZN2dwTlP99L79Ekf/ldSHeXPYxMW7HTTHV6N7BcNvD6//uKhLG11 1yfZy049sE9eb0vX/Mjmb+EkSCJVZ3kXf4RHDmrl+Dh/yWVrizRS1i/kB/FIng6EuU rK6O9lxxTatXQ== Message-ID: <0048210a-e186-49c7-9897-32c9b66336c6@kernel.org> Date: Fri, 10 Jul 2026 14:40:24 +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 2/2] mm/page_alloc: rename FPI_TRYLOCK -> FPI_NOLOCK Content-Language: en-US To: Brendan Jackman , Andrew Morton , Suren Baghdasaryan , Michal Hocko , Johannes Weiner , Zi Yan , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt , Shakeel Butt , Harry Yoo , Alexei Starovoitov Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev References: <20260710-spin-trylock-followup-v1-0-affb5fe5ed00@google.com> <20260710-spin-trylock-followup-v1-2-affb5fe5ed00@google.com> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/10/26 12:42, Brendan Jackman wrote: > As discussed in the linked patch, the there is some inconsistency between > "trylock" and "nolock" nomenclature, let's align it. Since "nolock" is > used in the public API it seems to have more mindshare so do that. > > The linked patch did this for the ALLOC_ flag but forgot about FPI_. > > Link: https://lore.kernel.org/all/20260703-alloc-trylock-v5-1-c87b714e19d3@google.com/ > Signed-off-by: Brendan Jackman Naming things is hard. Maybe it should have all been called "nospin". I don't know anymore :) _nolock() functions and ALLOC_NOLOCK are part of API, FPI_ is internal so it's not that urgent. Furthermore: > --- > mm/page_alloc.c | 18 +++++++++--------- > 1 file changed, 9 insertions(+), 9 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 5fe1c11f919d7..ba8d882072de5 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -90,7 +90,7 @@ typedef int __bitwise fpi_t; > #define FPI_TO_TAIL ((__force fpi_t)BIT(1)) > > /* Free the page without taking locks. Rely on trylock only. */ here's a "trylock" > -#define FPI_TRYLOCK ((__force fpi_t)BIT(2)) > +#define FPI_NOLOCK ((__force fpi_t)BIT(2)) And here's not anymore. > > /* free_pages_prepare() has already been called for page(s) being freed. */ > #define FPI_PREPARED ((__force fpi_t)BIT(3)) > @@ -1419,7 +1419,7 @@ static __always_inline bool __free_pages_prepare(struct page *page, > page_table_check_free(page, order); > pgalloc_tag_sub(page, 1 << order); > > - if (!PageHighMem(page) && !(fpi_flags & FPI_TRYLOCK)) { > + if (!PageHighMem(page) && !(fpi_flags & FPI_NOLOCK)) { > debug_check_no_locks_freed(page_address(page), > PAGE_SIZE << order); > debug_check_no_obj_freed(page_address(page), > @@ -1558,7 +1558,7 @@ static void free_one_page(struct zone *zone, struct page *page, > struct llist_head *llhead; > unsigned long flags; > > - if (unlikely(fpi_flags & FPI_TRYLOCK)) { > + if (unlikely(fpi_flags & FPI_NOLOCK)) { > if (!spin_trylock_irqsave(&zone->lock, flags)) { > add_page_to_zone_llist(zone, page, order); > return; > @@ -1569,7 +1569,7 @@ static void free_one_page(struct zone *zone, struct page *page, > > /* The lock succeeded. Process deferred pages. */ > llhead = &zone->trylock_free_pages; > - if (unlikely(!llist_empty(llhead) && !(fpi_flags & FPI_TRYLOCK))) { > + if (unlikely(!llist_empty(llhead) && !(fpi_flags & FPI_NOLOCK))) { > struct llist_node *llnode; > struct page *p, *tmp; > > @@ -2882,7 +2882,7 @@ static bool free_frozen_page_commit(struct zone *zone, > if (pcp->free_count < (batch << CONFIG_PCP_BATCH_SCALE_MAX)) > pcp->free_count += (1 << order); > > - if (unlikely(fpi_flags & FPI_TRYLOCK)) { > + if (unlikely(fpi_flags & FPI_NOLOCK)) { > /* > * Do not attempt to take a zone lock. Let pcp->count get > * over high mark temporarily. > @@ -2979,7 +2979,7 @@ static void __free_frozen_pages(struct page *page, unsigned int order, > migratetype = MIGRATE_MOVABLE; > } > > - if (unlikely((fpi_flags & FPI_TRYLOCK) && !can_spin_trylock())) { > + if (unlikely((fpi_flags & FPI_NOLOCK) && !can_spin_trylock())) { can_spin_trylock() was matched with FPI_TRYLOCK, now not anymore > add_page_to_zone_llist(zone, page, order); > return; > } > @@ -3001,7 +3001,7 @@ void free_frozen_pages(struct page *page, unsigned int order) > > void free_frozen_pages_nolock(struct page *page, unsigned int order) > { > - __free_frozen_pages(page, order, FPI_TRYLOCK); > + __free_frozen_pages(page, order, FPI_NOLOCK); > } > > /* > @@ -5409,7 +5409,7 @@ struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, > if (memcg_kmem_online() && (gfp & __GFP_ACCOUNT) && page && > unlikely(__memcg_kmem_charge_page(page, gfp, order) != 0)) { > __free_frozen_pages(page, order, > - alloc_flags & ALLOC_NOLOCK ? FPI_TRYLOCK : 0); > + alloc_flags & ALLOC_NOLOCK ? FPI_NOLOCK : 0); Although here it does improve things. Sigh. > page = NULL; > } > > @@ -5532,7 +5532,7 @@ EXPORT_SYMBOL(__free_pages); > */ > void free_pages_nolock(struct page *page, unsigned int order) > { > - ___free_pages(page, order, FPI_TRYLOCK); > + ___free_pages(page, order, FPI_NOLOCK); > } > > /** >