From: Frederic Weisbecker <frederic@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
Oleg Nesterov <oleg@redhat.com>, Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
John Stultz <john.stultz@linaro.org>,
Anna-Maria Behnsen <anna-maria@linutronix.de>,
Christoph Hellwig <hch@lst.de>
Subject: Re: [patch V2 20/38] posix-cpu-timers: Provide array based access to expiry cache
Date: Fri, 23 Aug 2019 19:33:39 +0200 [thread overview]
Message-ID: <20190823173338.GA18880@lenoir> (raw)
In-Reply-To: <20190821192921.105793824@linutronix.de>
On Wed, Aug 21, 2019 at 09:09:07PM +0200, Thomas Gleixner wrote:
> Using struct task_cputime for the expiry cache is a pretty odd choice and
> comes with magic defines to rename the fields for usage in the expiry
> cache.
>
> struct task_cputime is basically a u64 array with 3 members, but it has
> distinct members.
>
> The expiry cache content is different than the content of task_cputime
> because
>
> expiry[PROF] = task_cputime.stime + task_cputime.utime
> expiry[VIRT] = task_cputime.utime
> expiry[SCHED] = task_cputime.sum_exec_runtime
>
> So there is no direct mapping between task_cputime and the expiry cache and
> the #define based remapping is just a horrible hack.
>
> Having the expiry cache array based allows further simplification of the
> expiry code.
>
> To avoid an all in one cleanup which is hard to review add a temporary
> anonymous union into struct task_cputime which allows array based access to
> it. That requires to reorder the members. Add a build time sanity check to
> validate that the members are at the same place.
>
> The union and the build time checks will be removed after conversion.
>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
next prev parent reply other threads:[~2019-08-23 17:33 UTC|newest]
Thread overview: 137+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-21 19:08 [patch V2 00/38] posix-cpu-timers: Cleanup and consolidation Thomas Gleixner
2019-08-21 19:08 ` [patch V2 01/38] posix-cpu-timers: Provide task validation functions Thomas Gleixner
2019-08-21 22:33 ` Frederic Weisbecker
2019-08-21 23:03 ` Frederic Weisbecker
2019-08-23 15:33 ` Thomas Gleixner
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 02/38] posix-cpu-timers: Use common permission check in posix_cpu_clock_get() Thomas Gleixner
2019-08-21 23:40 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-29 11:00 ` kbuild test robot
2019-08-29 11:21 ` Thomas Gleixner
2019-08-30 1:08 ` [kbuild-all] " Philip Li
2019-08-29 11:23 ` kbuild test robot
2019-08-21 19:08 ` [patch V2 03/38] posix-cpu-timers: Use common permission check in posix_cpu_timer_create() Thomas Gleixner
2019-08-21 23:49 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 04/38] posix-cpu-timers: Provide quick sample function for itimer Thomas Gleixner
2019-08-22 12:13 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 05/38] itimers: Use quick sample function Thomas Gleixner
2019-08-22 12:15 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-29 23:47 ` kbuild test robot
2019-08-30 6:01 ` Thomas Gleixner
2019-08-21 19:08 ` [patch V2 06/38] posix-cpu-timers: Sample directly in timer check Thomas Gleixner
2019-08-22 12:30 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 07/38] posix-cpu-timers: Rename thread_group_cputimer() and make it static Thomas Gleixner
2019-08-22 12:41 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 08/38] posix-cpu-timers: Consolidate thread group sample code Thomas Gleixner
2019-08-22 13:49 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 09/38] posix-cpu-timers: Use clock ID in posix_cpu_timer_set() Thomas Gleixner
2019-08-22 13:58 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 10/38] posix-cpu-timers: Use clock ID in posix_cpu_timer_get() Thomas Gleixner
2019-08-22 14:07 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 11/38] posix-cpu-timers: Use clock ID in posix_cpu_timer_rearm() Thomas Gleixner
2019-08-22 14:12 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:08 ` [patch V2 12/38] posix-cpu-timers: Remove pointless return value check Thomas Gleixner
2019-08-22 14:15 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 13/38] posix-cpu-timers: Simplify sample functions Thomas Gleixner
2019-08-22 14:20 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 14/38] posix-cpu-timers: Get rid of pointer indirection Thomas Gleixner
2019-08-22 14:41 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 15/38] posix-cpu-timers: Sample task times once in expiry check Thomas Gleixner
2019-08-22 15:00 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 16/38] posix-cpu-timers: Move prof/virt_ticks into caller Thomas Gleixner
2019-08-22 15:05 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 17/38] posix-cpu-timers: Create a container struct Thomas Gleixner
2019-08-22 15:32 ` Frederic Weisbecker
2019-08-23 15:34 ` Thomas Gleixner
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 19/38] posix-cpu-timers: Move expiry cache into struct posix_cputimers Thomas Gleixner
2019-08-22 16:29 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 20/38] posix-cpu-timers: Provide array based access to expiry cache Thomas Gleixner
2019-08-23 17:33 ` Frederic Weisbecker [this message]
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 21/38] posix-cpu-timers: Simplify timer queueing Thomas Gleixner
2019-08-23 17:51 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 22/38] posix-cpu-timers: Simplify set_process_cpu_timer() Thomas Gleixner
2019-08-23 18:00 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 23/38] posix-cpu-timers: Switch check_*_timers() to array cache Thomas Gleixner
2019-08-23 18:13 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 24/38] posix-cpu-timers: Remove the odd field rename defines Thomas Gleixner
2019-08-23 18:36 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 25/38] posix-cpu-timers: Provide array based sample functions Thomas Gleixner
2019-08-23 22:08 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 26/38] posix-cpu-timers: Make expiry checks array based Thomas Gleixner
2019-08-23 22:44 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 27/38] posix-cpu-timers: Remove cputime_expires Thomas Gleixner
2019-08-23 22:50 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 28/38] posix-cpu-timers: Restructure expiry array Thomas Gleixner
2019-08-26 16:32 ` Frederic Weisbecker
2019-08-26 18:16 ` Thomas Gleixner
2019-08-26 18:22 ` [patch V3 " Thomas Gleixner
2019-08-26 19:45 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-26 21:06 ` [patch V2 28/38] " Frederic Weisbecker
2019-08-26 21:46 ` Thomas Gleixner
2019-08-21 19:09 ` [patch V2 29/38] posix-cpu-timers: Switch thread group sampling to array Thomas Gleixner
2019-08-26 21:12 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 30/38] posix-cpu-timers: Respect INFINITY for hard RTTIME limit Thomas Gleixner
2019-08-26 21:19 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 31/38] rlimit: Rewrite non-sensical RLIMIT_CPU comment Thomas Gleixner
2019-08-26 21:41 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 32/38] posix-cpu-timers: Get rid of zero checks Thomas Gleixner
2019-08-26 21:57 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 33/38] posix-cpu-timers: Consolidate timer expiry further Thomas Gleixner
2019-08-26 22:29 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 34/38] posix-cpu-timers: Get rid of 64bit divisions Thomas Gleixner
2019-08-26 22:51 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 35/38] posix-cpu-timers: Remove pointless comparisons Thomas Gleixner
2019-08-26 22:59 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 36/38] posix-cpu-timers: Deduplicate rlimit handling Thomas Gleixner
2019-08-26 23:13 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 37/38] posix-cpu-timers: Move state tracking to struct posix_cputimers Thomas Gleixner
2019-08-26 23:28 ` Frederic Weisbecker
2019-08-26 23:33 ` Thomas Gleixner
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-21 19:09 ` [patch V2 38/38] posix-cpu-timers: Utilize timerqueue for storage Thomas Gleixner
2019-08-27 0:48 ` Frederic Weisbecker
2019-08-27 6:08 ` Thomas Gleixner
2019-08-27 13:17 ` Frederic Weisbecker
2019-08-27 13:46 ` Thomas Gleixner
2019-08-27 19:31 ` [patch V3 " Thomas Gleixner
2019-08-27 22:23 ` Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2019-08-22 0:54 ` [patch V2 00/38] posix-cpu-timers: Cleanup and consolidation Christoph Hellwig
2019-08-22 1:02 ` Frederic Weisbecker
2019-08-22 1:02 ` Christoph Hellwig
[not found] ` <20190821192920.909530418@linutronix.de>
2019-08-22 16:06 ` [patch V2 18/38] sched: Move struct task_cputime to types.h Frederic Weisbecker
2019-08-28 10:16 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
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