From: Greg Donald <gdonald@gmail.com>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: linux-kernel@vger.kernel.org,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>
Subject: Re: find_busiest_group divide error
Date: Wed, 16 Jul 2014 16:47:18 -0500 [thread overview]
Message-ID: <20140716214718.GA11183@gmail.com> (raw)
In-Reply-To: <53C6EF16.30506@arm.com>
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On Wed, Jul 16, 2014 at 11:31:02PM +0200, Dietmar Eggemann wrote:
> My patch caffcdd8d27ba78730d5540396ce72ad022aff2c got rid of
> cpumask_clear(sched_group_cpus(sg)); and sg->sgp->power = 0; so
> reverting it (and replacing sg->sgp->power = 0 with
> sg->sgc->capacity = 0) should cure it too. (although the missing
> cpumask_clear() is the culprit on your machine here).
>
> Could I ask you to share the content of your /proc/cpuinfo file? I
> suspect it might be the same topology as the one Bruno just sent out
> (the one of a dual single core CPU with hyper-threading ?)
>
> https://lkml.org/lkml/2014/7/16/603
Sounds like what I have:
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Xeon(TM) CPU 2.00GHz
stepping : 7
microcode : 0x25
cpu MHz : 1993.502
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fdiv_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs
bts cid
bogomips : 3987.00
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Xeon(TM) CPU 2.00GHz
stepping : 7
microcode : 0x25
cpu MHz : 1993.502
cache size : 512 KB
physical id : 3
siblings : 2
core id : 0
cpu cores : 1
apicid : 6
initial apicid : 6
fdiv_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs
bts cid
bogomips : 3987.39
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:
processor : 2
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Xeon(TM) CPU 2.00GHz
stepping : 7
microcode : 0x25
cpu MHz : 1993.502
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 1
initial apicid : 1
fdiv_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs
bts cid
bogomips : 3987.34
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:
processor : 3
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Xeon(TM) CPU 2.00GHz
stepping : 7
microcode : 0x25
cpu MHz : 1993.502
cache size : 512 KB
physical id : 3
siblings : 2
core id : 0
cpu cores : 1
apicid : 7
initial apicid : 7
fdiv_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs
bts cid
bogomips : 3987.42
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:
--
Greg Donald
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prev parent reply other threads:[~2014-07-16 21:47 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-14 16:56 find_busiest_group divide error Greg Donald
2014-07-16 15:27 ` Peter Zijlstra
2014-07-16 16:40 ` Bruno Wolff III
2014-07-16 17:52 ` Greg Donald
2014-07-16 21:31 ` Dietmar Eggemann
2014-07-16 21:47 ` Greg Donald [this message]
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