From:   Thomas Gleixner <tglx@linutronix.de>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Peter Oskolkov <posk@posk.io>, Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Linux Memory Management List <linux-mm@kvack.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-api@vger.kernel.org, Paul Turner <pjt@google.com>,
        Ben Segall <bsegall@google.com>,
        Peter Oskolkov <posk@google.com>,
        Andrei Vagin <avagin@google.com>, Jann Horn <jannh@google.com>,
        Thierry Delisle <tdelisle@uwaterloo.ca>
Subject: Re: [PATCH v0.9.1 3/6] sched/umcg: implement UMCG syscalls
In-Reply-To: <YaFY0KqfPhmZjK7n@hirez.programming.kicks-ass.net>
References: <20211122211327.5931-1-posk@google.com>
 <20211122211327.5931-4-posk@google.com>
 <20211124200822.GF721624@worktop.programming.kicks-ass.net>
 <CAFTs51Uka8VRCHuGidw7mRwATufp87U6S8SWUVod_kU-h6T3ew@mail.gmail.com>
 <YaEUts3RbOLyvAjl@hirez.programming.kicks-ass.net> <87a6hqhbgh.ffs@tglx>
 <YaFY0KqfPhmZjK7n@hirez.programming.kicks-ass.net>
Date:   Sat, 27 Nov 2021 01:45:20 +0100
Message-ID: <87tufyfmu7.ffs@tglx>
MIME-Version: 1.0
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On Fri, Nov 26 2021 at 22:59, Peter Zijlstra wrote:
> On Fri, Nov 26, 2021 at 10:08:14PM +0100, Thomas Gleixner wrote:
>> > +		if (timo)
>> > +			hrtimer_sleeper_start_expires(&timeout, HRTIMER_MODE_ABS);
>> > +
>> > +		freezable_schedule();
>> 
>> You can replace the whole hrtimer foo with
>> 
>>                 if (!schedule_hrtimeout_range_clock(timo ? &timo : NULL,
>>                                                     tsk->timer_slack_ns,
>>                                                     HRTIMER_MODE_ABS,
>>                                                     tsk->umcg_clock)) {
>>                 	ret = -ETIMEOUT;
>>                         break;
>>                 }
>
> That seems to loose the freezable crud.. then again, since we're
> interruptible, that shouldn't matter. Lemme go do that.

We could add a freezable wrapper for that if necessary.

Thanks,

        tglx