All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andi Kleen <ak@linux.intel.com>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andi Kleen <andi@firstfloor.org>,
	akpm@linux-foundation.org, linux-mm@kvack.org
Subject: Re: [PATCH] mm: Simplify and batch working set shadow pages LRU isolation locking
Date: Fri, 27 Oct 2017 10:22:05 -0700	[thread overview]
Message-ID: <20171027172205.GA22894@tassilo.jf.intel.com> (raw)
In-Reply-To: <20171027170156.GA1743@cmpxchg.org>

> The nlru->lock in list_lru_shrink_walk() is the only thing that keeps
> truncation blocked on workingset_update_node() -> list_lru_del() and
> so ultimately keeping it from freeing the radix tree node.
> 
> It's not safe to access the nodes on the private list after that.

True.

> 
> Batching mapping->tree_lock is possible, but you have to keep the
> lock-handoff scheme. Pass a &mapping to list_lru_shrink_walk() and
> only unlock and spin_trylock(&mapping->tree_lock) if it changes?

Yes something like that could work. Thanks.

-Andi

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2017-10-27 17:22 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-10-26 23:48 [PATCH] mm: Simplify and batch working set shadow pages LRU isolation locking Andi Kleen
2017-10-27 17:01 ` Johannes Weiner
2017-10-27 17:22   ` Andi Kleen [this message]
2017-10-27 20:59     ` Daniel Jordan
2017-10-27 20:51 ` Daniel Jordan
2017-11-08  1:56 ` [lkp-robot] [mm] 47bd678bc7: WARNING:at_mm/workingset.c:#scan_shadow_nodes kernel test robot
2017-11-08  1:56   ` kernel test robot
2017-11-09  0:03   ` Andi Kleen
2017-11-09  0:03     ` Andi Kleen

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=20171027172205.GA22894@tassilo.jf.intel.com \
    --to=ak@linux.intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=andi@firstfloor.org \
    --cc=hannes@cmpxchg.org \
    --cc=linux-mm@kvack.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.