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 25423524AE4 for ; Fri, 18 Sep 2026 20:42:21 +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=1789764145; cv=none; b=ifQSV2nYMeNkhM9q5wvNTHzUI8f8d1LvAsJk8xDbyoRE5uXgI7WZ7rLAQolTG544yP5PUe+Q4OXDsHALfz1xSTlq9jcBjCtlJG0JOy2ed5D8ewyzPc+82NUcZiLEcmp8ad7bIEi1OVAw6pEAwOUgasSgQKRNLah+cqxhMGJO6w0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789764145; c=relaxed/simple; bh=7T44exYOgwIGgLRI+JYrkkvQ+Gn6reEyWOTdJO4Q3k0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=B+IF7dX2F/I5mAMYthJpVvBn3v2EOMq0UHaggX5kasy+JOM3qJv7K0PdH2jpnJjuE67epM+jgkLdRNXG3PnHC2yMBM8K8dJTKlov1GZ/4jVGciiawN5YpYMIPCl4Wz7EeUXM/8ZJIdBgJgZ1Sw/eP8Jdh9Yc4fRtcUWSpOJKktY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W1OMWLjk; 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="W1OMWLjk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEBE71F000FF; Fri, 18 Sep 2026 20:42:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789764139; bh=q7DJZ+YMyz4y6+e3tw5qlknVYqBVKK0aejFZ6SnY5DE=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=W1OMWLjke5dVKM1Z49TWdMIy8J23eUDrg4ySHj3komwwgMoJi1COcHqkTEd0eXHyO 4PS7oLK2G5Wpkhh9R1F8wyMZnZFXeGg05rJQNCQgMHGvxzn+zeW3PQGcwC/bYs6tpt d71InlR2HNN1fKC6ZbIPL0qcATvcCPSY809rh14gH8i/Y0Uo8Xdrav3NazUcxj2Jxv htqcPOzNmHeYgJZnAU2zwyVOGS4rVO7bjR21ezaaOQ7E4MkBLCaq0AU9u3WuMic9vZ wOYZMdvzW0ImoZRlIIwx6vwN+4Nx7J/ltTtcD7cXblwh2XyHjnEal+GG+cMd39BTdM NDg6ec4sdgzBA== Message-ID: Date: Fri, 18 Sep 2026 22:42:12 +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 v2 1/2] mm: refactor find_next_best_node to find_next_best_node_in To: Gregory Price , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, akpm@linux-foundation.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, brendan.jackman@linux.dev, hannes@cmpxchg.org, ziy@nvidia.com, Balbir Singh References: <20260912030424.2889731-1-gourry@gourry.net> <20260912030424.2889731-2-gourry@gourry.net> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/12/26 05:04, Gregory Price wrote: > find_next_best_node() picks the next-closest node for a fallback list > from the full N_MEMORY set. Refactor it into find_next_best_node_in(), > which takes an explicit candidates nodemask. > > This enables building fallback lists with non-N_MEMORY candidates. > > No functional change: every caller still selects from N_MEMORY. > > Reviewed-by: Vlastimil Babka (SUSE) > Acked-by: Balbir Singh > Signed-off-by: Gregory Price > --- > mm/internal.h | 6 ++++-- > mm/memory-tiers.c | 7 ++++--- > mm/page_alloc.c | 13 ++++++++----- > 3 files changed, 16 insertions(+), 10 deletions(-) > > diff --git a/mm/internal.h b/mm/internal.h > index da14c56fb24e..1519dd21a900 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -1133,7 +1133,8 @@ extern int node_reclaim_mode; > > extern unsigned long node_reclaim(struct pglist_data *pgdat, > gfp_t gfp_mask, unsigned int order); > -extern int find_next_best_node(int node, nodemask_t *used_node_mask); > +int find_next_best_node_in(int node, nodemask_t *used_node_mask, > + const nodemask_t *candidates); Just curious, for your use case, wouldn't it be enough to pass N_MEMORY? Or do we expect to pass other actual node masks that are not derived from node_states? -- Cheers, David