From: Rik van Riel <riel@redhat.com>
To: Dave Hansen <dave.hansen@linux.intel.com>, oleg@redhat.com
Cc: sbsiddha@gmail.com, luto@amacapital.net, tglx@linutronix.de,
mingo@redhat.com, hpa@zytor.com, fenghua.yu@intel.com,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/3] x86,fpu: use disable_task_lazy_fpu_restore helper
Date: Fri, 30 Jan 2015 16:48:37 -0500 [thread overview]
Message-ID: <54CBFC35.6090005@redhat.com> (raw)
In-Reply-To: <54CBFBC7.7060304@linux.intel.com>
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Hash: SHA1
On 01/30/2015 04:46 PM, Dave Hansen wrote:
> On 01/30/2015 09:49 AM, riel@redhat.com wrote:
>> @@ -440,8 +440,9 @@ static inline fpu_switch_t
>> switch_fpu_prepare(struct task_struct *old, struct ta
>> new->thread.fpu_counter > 5); if (__thread_has_fpu(old)) { if
>> (!__save_init_fpu(old)) - cpu = ~0; - old->thread.fpu.last_cpu
>> = cpu; + task_disable_lazy_fpu_restore(old); + else +
>> old->thread.fpu.last_cpu = cpu;
>
> What is the 'else' doing here? It seems a bit disconnected from
> the other parts of the patch.
The assignment was already there before, but we would set
cpu to ~0 if __save_init_fpu failed.
Now there are different branches for failure and success,
with the success branch having the same assignment that
was there before.
- --
All rights reversed
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next prev parent reply other threads:[~2015-01-30 21:49 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-23 19:34 question about save_xstate_sig() - WHY DOES THIS WORK? Rik van Riel
2015-01-23 20:51 ` [PATCH, RFC] x86,fpu: make signal handling xstate save & restore preemption safe Rik van Riel
2015-01-23 21:07 ` question about save_xstate_sig() - WHY DOES THIS WORK? H. Peter Anvin
2015-01-24 13:39 ` Rik van Riel
2015-01-24 20:20 ` Oleg Nesterov
2015-01-26 23:27 ` Rik van Riel
2015-01-27 19:40 ` Oleg Nesterov
2015-01-27 20:27 ` Rik van Riel
2015-01-27 20:50 ` Rik van Riel
2015-01-29 21:01 ` Oleg Nesterov
2015-01-29 20:45 ` Oleg Nesterov
2015-01-29 20:52 ` Rik van Riel
2015-01-29 21:00 ` [PATCH RFC] x86,fpu: merge save_init_fpu & unlazy_fpu Rik van Riel
2015-01-29 21:21 ` Oleg Nesterov
2015-01-29 21:07 ` [PATCH 0/3]: x86, fpu: unlazy_fpu fixes/cleanups Oleg Nesterov
2015-01-29 21:07 ` [PATCH 1/3] x86, fpu: unlazy_fpu: don't reset thread.fpu_counter Oleg Nesterov
2015-01-29 21:26 ` Rik van Riel
2015-01-29 21:08 ` [PATCH 2/3] x86, fpu: unlazy_fpu: don't do __thread_fpu_end() if use_eager_fpu() Oleg Nesterov
2015-01-29 21:36 ` Rik van Riel
2015-01-29 21:49 ` Oleg Nesterov
2015-01-29 21:53 ` Rik van Riel
2015-01-29 21:54 ` Rik van Riel
2015-01-29 21:08 ` [PATCH 3/3] x86, fpu: kill save_init_fpu(), change math_error() to use unlazy_fpu() Oleg Nesterov
2015-01-29 21:54 ` Rik van Riel
2015-01-29 21:17 ` [PATCH 0/3]: x86, fpu: unlazy_fpu fixes/cleanups Dave Hansen
2015-01-29 21:33 ` Oleg Nesterov
2015-01-29 21:43 ` Dave Hansen
2015-01-29 21:56 ` Oleg Nesterov
2015-01-29 21:58 ` Rik van Riel
2015-01-29 23:26 ` Dave Hansen
2015-01-30 1:33 ` Rik van Riel
2015-02-02 18:11 ` Dave Hansen
2015-01-30 12:45 ` Oleg Nesterov
2015-01-30 13:30 ` Oleg Nesterov
2015-01-30 13:43 ` Oleg Nesterov
2015-01-30 17:49 ` [PATCH 0/3] cleanups to the disable lazy fpu restore code riel
2015-01-30 17:49 ` [PATCH 1/3] x86,fpu: move lazy restore functions up a few lines riel
2015-01-30 17:49 ` [PATCH 2/3] x86,fpu: introduce task_disable_lazy_fpu_restore helper riel
2015-01-30 17:49 ` [PATCH 3/3] x86,fpu: use disable_task_lazy_fpu_restore helper riel
2015-01-30 21:46 ` Dave Hansen
2015-01-30 21:48 ` Rik van Riel [this message]
2015-02-02 17:56 ` Rik van Riel
2015-02-02 18:00 ` [PATCH 0/6] cleanups to lazy FPU restore code riel
2015-02-02 18:00 ` [PATCH 1/6] x86,fpu: move lazy restore functions up a few lines riel
2015-02-02 18:00 ` [PATCH 2/6] x86,fpu: introduce task_disable_lazy_fpu_restore helper riel
2015-02-02 18:00 ` [PATCH 3/6] x86,fpu: use an explicit if/else in switch_fpu_prepare riel
2015-02-02 18:00 ` [PATCH 4/6] x86,fpu: use disable_task_lazy_fpu_restore helper riel
2015-02-02 19:21 ` Oleg Nesterov
2015-02-02 19:43 ` Rik van Riel
2015-02-03 19:08 ` Oleg Nesterov
2015-02-03 22:01 ` Rik van Riel
2015-02-06 16:42 ` Rik van Riel
2015-02-02 18:00 ` [PATCH 5/6] x86,fpu: also check fpu_lazy_restore when use_eager_fpu riel
2015-02-02 18:55 ` Oleg Nesterov
2015-02-02 19:19 ` Rik van Riel
2015-02-02 18:00 ` [PATCH 6/6] x86,fpu: remove redundant increments of fpu_counter riel
2015-02-02 18:34 ` Oleg Nesterov
2015-02-02 18:40 ` Rik van Riel
2015-02-18 23:40 ` Ingo Molnar
2015-02-18 23:54 ` Borislav Petkov
2015-02-19 20:09 ` Oleg Nesterov
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