[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAJuCfpHMRM1GyzCA_=v5V2kUZbprvNJD1aFmpF58vm0w4eWBHw@mail.gmail.com>
Date: Tue, 15 Oct 2024 09:26:24 -0700
From: Suren Baghdasaryan <surenb@...gle.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: kent.overstreet@...ux.dev, corbet@....net, arnd@...db.de,
mcgrof@...nel.org, rppt@...nel.org, paulmck@...nel.org, thuth@...hat.com,
tglx@...utronix.de, bp@...en8.de, xiongwei.song@...driver.com,
ardb@...nel.org, david@...hat.com, vbabka@...e.cz, mhocko@...e.com,
hannes@...xchg.org, roman.gushchin@...ux.dev, dave@...olabs.net,
willy@...radead.org, liam.howlett@...cle.com, pasha.tatashin@...een.com,
souravpanda@...gle.com, keescook@...omium.org, dennis@...nel.org,
jhubbard@...dia.com, yuzhao@...gle.com, vvvvvv@...gle.com,
rostedt@...dmis.org, iamjoonsoo.kim@....com, rientjes@...gle.com,
minchan@...gle.com, kaleshsingh@...gle.com, linux-doc@...r.kernel.org,
linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org, linux-mm@...ck.org,
linux-modules@...r.kernel.org, kernel-team@...roid.com
Subject: Re: [PATCH v3 0/5] page allocation tag compression
On Mon, Oct 14, 2024 at 6:48 PM Suren Baghdasaryan <surenb@...gle.com> wrote:
>
> On Mon, Oct 14, 2024 at 4:32 PM Andrew Morton <akpm@...ux-foundation.org> wrote:
> >
> > On Mon, 14 Oct 2024 13:36:41 -0700 Suren Baghdasaryan <surenb@...gle.com> wrote:
> >
> > > Patch #2 copies module tags into virtually contiguous memory which
> > > serves two purposes:
> > > - Lets us deal with the situation when module is unloaded while there
> > > are still live allocations from that module. Since we are using a copy
> > > version of the tags we can safely unload the module. Space and gaps in
> > > this contiguous memory are managed using a maple tree.
> >
> > Does this make "lib: alloc_tag_module_unload must wait for pending
> > kfree_rcu calls" unneeded?
>
> With this change we can unload a module even when tags from that
> module are still in use. However "lib: alloc_tag_module_unload must
> wait for pending kfree_rcu calls" would still be useful because it
> will allow us to release the memory occupied by module's tags and let
> other modules use that memory.
>
> > If so, that patch was cc:stable (justifyably), so what to do about that?
>
> Now that I posted this patchset I'll work on backporting "lib:
> alloc_tag_module_unload must wait for pending kfree_rcu calls" and its
> prerequisites to 6.10 and 6.11. I'll try to get backports out
> tomorrow.
I prepared 6.10 and 6.11 backports for
https://lore.kernel.org/all/20241007205236.11847-1-fw@strlen.de but
will wait for it to get merged into Linus' tree before posting them to
stable.
Thanks,
Suren.
> I don't think we need to backport this patchset to pre-6.12 kernels
> since this is an improvement and not a bug fix. But if it's needed I
> can backport it as well.
> Thanks,
> Suren.
Powered by blists - more mailing lists