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From:   Alexander Potapenko <glider@google.com>
Date:   Mon, 9 Oct 2023 11:35:38 +0200
Message-ID: <CAG_fn=VSSQuR2VLEv-t+ByG7AbfDxjeR=oPvpaPkMOq4ZoEs4A@mail.gmail.com>
Subject: Re: [PATCH v2 07/19] lib/stackdepot: rework helpers for depot_alloc_stack
To:     andrey.konovalov@linux.dev
Cc:     Marco Elver <elver@google.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Vlastimil Babka <vbabka@suse.cz>, kasan-dev@googlegroups.com,
        Evgenii Stepanov <eugenis@google.com>,
        Oscar Salvador <osalvador@suse.de>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Andrey Konovalov <andreyknvl@google.com>
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On Mon, Oct 9, 2023 at 10:59=E2=80=AFAM Alexander Potapenko <glider@google.=
com> wrote:
>
> On Wed, Sep 13, 2023 at 7:15=E2=80=AFPM <andrey.konovalov@linux.dev> wrot=
e:
> >
> > From: Andrey Konovalov <andreyknvl@google.com>
> >
> > Split code in depot_alloc_stack and depot_init_pool into 3 functions:
> >
> > 1. depot_keep_next_pool that keeps preallocated memory for the next poo=
l
> >    if required.
> >
> > 2. depot_update_pools that moves on to the next pool if there's no spac=
e
> >    left in the current pool, uses preallocated memory for the new curre=
nt
> >    pool if required, and calls depot_keep_next_pool otherwise.
> >
> > 3. depot_alloc_stack that calls depot_update_pools and then allocates
> >    a stack record as before.
> >
> > This makes it somewhat easier to follow the logic of depot_alloc_stack
> > and also serves as a preparation for implementing the eviction of stack
> > records from the stack depot.
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> Reviewed-by: Alexander Potapenko <glider@google.com>
>
>
> > +static void depot_keep_next_pool(void **prealloc)
> >  {
> >         /*
> > -        * If the next pool is already initialized or the maximum numbe=
r of
> > +        * If the next pool is already saved or the maximum number of
> >          * pools is reached, do not use the preallocated memory.
> >          */
> >         if (!next_pool_required)
> It's not mentioned at the top of the file that next_pool_required is
> protected by pool_lock, but it is, correct?
> Can you please update the comment to reflect that?

You're adding lockdep annotations in patch 11, which are pretty
self-descriptive.
Feel free to ignore my comment above.