From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.219 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793685258; b=WBm8RmvavLvTJ2Cjy4zetuh3zYmLmW39E5qUpMMWmZc+sTydOtp8nOX/IMgF4hqyc/Y0 XKmc+TdyJQAfaDTzOseivW9b0EPpCgvP4M/eXuKQkGYOw9buLLblzlZulkCm8TkzW5edg vZ32g966gGEbmA+L6cO+/UAf7Zh065G9vigOP7+Dar7r6DDH6VZGlO9Knrit04FlNRxgy IPjWkoW5LP4YSceGKAn/vWf/5Q+a9rpmC1lxbdmr18f4Y8b06YfydCptWDn4xVrVGdV01 XeeSIHuY40y7ftinbygZoL81lNUjt96y25+uhtI3/cDovcAf9dkpLFA6mu84ih2ph/g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793685258; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=f6tohwCPgHiuZF8eRH66ZKcFUC+TlKOu4ZWfBkxIU9w=; b=mUYmgB3pyXs3Qh3lK20RJxtPytvQh6U/QwWDELx0ZMcAbX5K1YodxeDOCExzbBm6q5v9 TJZbngtvHFJ/TdmrrImyhCS1pWhfQaP6nB+fXgSehCxd2+kRVghHYWgvuXRELAVDJ4b3F 41PZoQ6QTdHLmyRl3MLMT12BbZl2dhgEsqR6SjhCLrnPIm90qdUoPUNmKt9WTayrUcQxV xTujpE6ZfqWsVvNK4zV8SLRKJnhSPixEHjy8+tp5bI0HbJ0hwm366AxPFIcjGcMzOh70W puK+zjDiLvtfDzpsGYwNLY24NcKMYNHoQWt5QwLVFMHvUM9gKn15rbHyvn6QhJhDmPw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b="PU6M/JuI"; arc=none smtp.remote-ip=95.215.58.219 Received: from mta1.migadu.com (out-219.mta1.migadu.com [95.215.58.219]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 88270606A32C for ; Tue, 3 Nov 2026 05:54:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 88270606A32C Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=PU6M/JuI X-Envelope-To: cgroups@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=0iTU/obU9AJ9W0pesgfQNaEftQkREMOsnsvVS/OmldY=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793685254; v=1; x=1794290054; b=PU6M/JuIkSLzUXuS6JZKKUvE//74A4tu1nNGmYcFb/OMTL0YL2iWlmVRngQpvLppWY+UhK4L kOzLqJsPN0sy3ZFQ/p/WeBzIG0EjJn/+UE88cigpF9T1Kfjp+xeur+8O/wE60EIjkouagxq2puf 25tElufqBKwzf+kZFylFCdkE= X-Envelope-To: cgroups@vger.kernel.org Received: by mta10.migadu.com with ESMTPS id 4e3eec371c58ba17; Tue, 03 Nov 2026 05:54:14 +0000 X-Mizu-Trace-ID: 4e3eec371c58ba17 X-Migadu-Flow: FLOW_OUT Date: Tue, 3 Nov 2026 13:54:07 +0800 From: Baoquan He To: Ridong Chen Cc: Steven Rostedt , Masami Hiramatsu , Andrew Morton , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Dave Chinner , Mathieu Desnoyers , Muchun Song , Qi Zheng , David Hildenbrand , Lorenzo Stoakes , Kairui Song , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baolin Wang , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, "open list:BPF [MISC]:Keyword:(?:b|_)bpf(?:b|_)" , Ridong Chen Subject: Re: [PATCH v6 6/7] mm/mglru: add lruvec_gen_size() helper Message-ID: References: <20261103025610.3738894-1-ridong.chen@linux.dev> <20261103025610.3738894-7-ridong.chen@linux.dev> X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261103025610.3738894-7-ridong.chen@linux.dev> On 11/03/26 at 10:56am, Ridong Chen wrote: > From: Ridong Chen > > The number of pages of a given type in a generation is computed by > summing lrugen->nr_pages[gen][type][] over all zones and clamping each > per-zone counter to >= 0, since the counters are updated locklessly and > can transiently go negative. This loop is open-coded in > lruvec_evictable_size() and in the debugfs lru_gen output. > > Add lruvec_gen_size() to compute it from a seq, and convert both users. > Put it in mm/vmscan.h so that the vmscan tracepoints, which include that > header, can use it as well. > An upcoming tracepoint and the MGLRU swappiness rework will also use it. > > No functional change. > > Suggested-by: Barry Song > Signed-off-by: Ridong Chen > --- > mm/vmscan.c | 18 ++++++------------ > mm/vmscan.h | 16 ++++++++++++++++ > 2 files changed, 22 insertions(+), 12 deletions(-) LGTM, Reviewed-by: Baoquan He > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 3054175717ab..1581b73aec56 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -4207,18 +4207,15 @@ static void set_initial_priority(struct pglist_data *pgdat, struct scan_control > > static unsigned long lruvec_evictable_size(struct lruvec *lruvec, int swappiness) > { > - int gen, type, zone; > + int type; > unsigned long seq, total = 0; > struct lru_gen_folio *lrugen = &lruvec->lrugen; > DEFINE_MAX_SEQ(lruvec); > DEFINE_MIN_SEQ(lruvec); > > for_each_evictable_type(type, swappiness) { > - for (seq = min_seq[type]; seq <= max_seq; seq++) { > - gen = lru_gen_from_seq(seq); > - for (zone = 0; zone < MAX_NR_ZONES; zone++) > - total += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); > - } > + for (seq = min_seq[type]; seq <= max_seq; seq++) > + total += lruvec_gen_size(lrugen, type, seq); > } > > return total; > @@ -5723,20 +5720,17 @@ static int lru_gen_seq_show(struct seq_file *m, void *v) > seq = 0; > > for (; seq <= max_seq; seq++) { > - int type, zone; > + int type; > int gen = lru_gen_from_seq(seq); > unsigned long birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); > > seq_printf(m, " %10lu %10u", seq, jiffies_to_msecs(jiffies - birth)); > > for (type = 0; type < ANON_AND_FILE; type++) { > - unsigned long size = 0; > char mark = full && seq < min_seq[type] ? 'x' : ' '; > > - for (zone = 0; zone < MAX_NR_ZONES; zone++) > - size += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); > - > - seq_printf(m, " %10lu%c", size, mark); > + seq_printf(m, " %10lu%c", > + lruvec_gen_size(lrugen, type, seq), mark); > } > > seq_putc(m, '\n'); > diff --git a/mm/vmscan.h b/mm/vmscan.h > index adb22e80d760..c6b583fc7493 100644 > --- a/mm/vmscan.h > +++ b/mm/vmscan.h > @@ -3,6 +3,7 @@ > #define _MM_VMSCAN_H > > #include > +#include > #include > #include > #include > @@ -115,4 +116,19 @@ struct scan_control { > struct reclaim_state reclaim_state; > }; > > +#ifdef CONFIG_LRU_GEN > +/* The number of pages of @type in the generation @seq, summed over all zones */ > +static inline unsigned long lruvec_gen_size(struct lru_gen_folio *lrugen, > + int type, unsigned long seq) > +{ > + int gen = lru_gen_from_seq(seq); > + unsigned long size = 0; > + > + for (int zone = 0; zone < MAX_NR_ZONES; zone++) > + size += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); > + > + return size; > +} > +#endif /* CONFIG_LRU_GEN */ > + > #endif /* _MM_VMSCAN_H */ > -- > 2.34.1 >