linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vlastimil Babka <vbabka@suse.cz>
To: Mel Gorman <mgorman@techsingularity.net>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: Chuck Lever <chuck.lever@oracle.com>,
	Jesper Dangaard Brouer <brouer@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>, Michal Hocko <mhocko@kernel.org>,
	Linux-MM <linux-mm@kvack.org>,
	Linux-RT-Users <linux-rt-users@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/9] mm/page_alloc: Convert per-cpu list protection to local_lock
Date: Thu, 22 Apr 2021 14:34:28 +0200	[thread overview]
Message-ID: <e9744c08-8384-70d1-26bc-d7e73e88ded2@suse.cz> (raw)
In-Reply-To: <20210422111441.24318-3-mgorman@techsingularity.net>

On 4/22/21 1:14 PM, Mel Gorman wrote:
> There is a lack of clarity of what exactly local_irq_save/local_irq_restore
> protects in page_alloc.c . It conflates the protection of per-cpu page
> allocation structures with per-cpu vmstat deltas.
> 
> This patch protects the PCP structure using local_lock which for most
> configurations is identical to IRQ enabling/disabling. The scope of the
> lock is still wider than it should be but this is decreased later.
> 
> It is possible for the local_lock to be embedded safely within struct
> per_cpu_pages but it adds complexity to free_unref_page_list.
> 
> [lkp@intel.com: Make pagesets static]
> Signed-off-by: Mel Gorman <mgorman@techsingularity.net>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

  reply	other threads:[~2021-04-22 12:34 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-22 11:14 [PATCH 0/9 v5] Use local_lock for pcp protection and reduce stat overhead Mel Gorman
2021-04-22 11:14 ` [PATCH 1/9] mm/page_alloc: Split per cpu page lists and zone stats Mel Gorman
2021-04-22 12:19   ` Vlastimil Babka
2021-04-22 11:14 ` [PATCH 2/9] mm/page_alloc: Convert per-cpu list protection to local_lock Mel Gorman
2021-04-22 12:34   ` Vlastimil Babka [this message]
2021-04-22 11:14 ` [PATCH 3/9] mm/vmstat: Convert NUMA statistics to basic NUMA counters Mel Gorman
2021-04-22 15:18   ` Vlastimil Babka
2021-04-23  8:32     ` Mel Gorman
2021-04-22 11:14 ` [PATCH 4/9] mm/vmstat: Inline NUMA event counter updates Mel Gorman
2021-04-22 11:14 ` [PATCH 5/9] mm/page_alloc: Batch the accounting updates in the bulk allocator Mel Gorman
2021-04-22 11:14 ` [PATCH 6/9] mm/page_alloc: Reduce duration that IRQs are disabled for VM counters Mel Gorman
2021-04-22 11:14 ` [PATCH 7/9] mm/page_alloc: Explicitly acquire the zone lock in __free_pages_ok Mel Gorman
2021-04-22 11:14 ` [PATCH 8/9] mm/page_alloc: Avoid conflating IRQs disabled with zone->lock Mel Gorman
2021-04-22 11:14 ` [PATCH 9/9] mm/page_alloc: Update PGFREE outside the zone lock in __free_pages_ok Mel Gorman
2021-05-12  9:54 [PATCH 0/9 v6] Use local_lock for pcp protection and reduce stat overhead Mel Gorman
2021-05-12  9:54 ` [PATCH 2/9] mm/page_alloc: Convert per-cpu list protection to local_lock Mel Gorman

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=e9744c08-8384-70d1-26bc-d7e73e88ded2@suse.cz \
    --to=vbabka@suse.cz \
    --cc=akpm@linux-foundation.org \
    --cc=brouer@redhat.com \
    --cc=chuck.lever@oracle.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=mgorman@techsingularity.net \
    --cc=mhocko@kernel.org \
    --cc=mingo@kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).