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From:   Suren Baghdasaryan <surenb@google.com>
Date:   Thu, 26 Oct 2023 18:33:09 +0000
Message-ID: <CAJuCfpH1pG513-FUE_28MfJ7xbX=9O-auYUjkxKLmtve_6rRAw@mail.gmail.com>
Subject: Re: [PATCH v2 28/39] timekeeping: Fix a circular include dependency
To:     Thomas Gleixner <tglx@linutronix.de>
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On Wed, Oct 25, 2023 at 5:33=E2=80=AFPM Thomas Gleixner <tglx@linutronix.de=
> wrote:
>
> On Tue, Oct 24 2023 at 06:46, Suren Baghdasaryan wrote:
> > From: Kent Overstreet <kent.overstreet@linux.dev>
> >
> > This avoids a circular header dependency in an upcoming patch by only
> > making hrtimer.h depend on percpu-defs.h
>
> What's the actual dependency problem?

Sorry for the delay.
When we instrument per-cpu allocations in [1] we need to include
sched.h in percpu.h to be able to use alloc_tag_save(). sched.h
includes hrtimer.h. So, without this change we end up with a circular
inclusion: percpu.h->sched.h->hrtimer.h->percpu.h

[1] https://lore.kernel.org/all/20231024134637.3120277-32-surenb@google.com=
/

>