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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Suren Baghdasaryan <surenb@google.com>
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Subject: Re: [PATCH v2 28/39] timekeeping: Fix a circular include dependency
In-Reply-To: <CAJuCfpH1pG513-FUE_28MfJ7xbX=9O-auYUjkxKLmtve_6rRAw@mail.gmail.com>
References: <20231024134637.3120277-1-surenb@google.com>
 <20231024134637.3120277-29-surenb@google.com> <87h6me620j.ffs@tglx>
 <CAJuCfpH1pG513-FUE_28MfJ7xbX=9O-auYUjkxKLmtve_6rRAw@mail.gmail.com>
Date:   Fri, 27 Oct 2023 01:05:48 +0200
Message-ID: <87jzr93rxv.ffs@tglx>
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On Thu, Oct 26 2023 at 18:33, Suren Baghdasaryan wrote:
> On Wed, Oct 25, 2023 at 5:33=E2=80=AFPM Thomas Gleixner <tglx@linutronix.=
de> wrote:
>> > 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

Including sched.h in percpu.h is fundamentally wrong as sched.h is the
initial place of all header recursions.

There is a reason why a lot of funtionalitiy has been split out of
sched.h into seperate headers over time in order to avoid that.

Thanks,

        tglx