Re: [RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-30 Thread Will Deacon
On Fri, Sep 27, 2013 at 03:20:10PM +0100, Jiang Liu wrote: > On 09/27/2013 06:59 PM, Will Deacon wrote: > > On Fri, Sep 27, 2013 at 09:04:46AM +0100, Jiang Liu wrote: > >> diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c > >> index 267e54a..a81af5f 100644 > >> ---

Re: [RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-30 Thread Will Deacon
On Fri, Sep 27, 2013 at 03:20:10PM +0100, Jiang Liu wrote: On 09/27/2013 06:59 PM, Will Deacon wrote: On Fri, Sep 27, 2013 at 09:04:46AM +0100, Jiang Liu wrote: diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 267e54a..a81af5f 100644 ---

Re: [RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-27 Thread Jiang Liu
On 09/27/2013 06:59 PM, Will Deacon wrote: > On Fri, Sep 27, 2013 at 09:04:46AM +0100, Jiang Liu wrote: >> From: Jiang Liu >> >> Use PF_USED_MATH flag to mark whether the thread has accessed any FPSIMD >> registers, so we could avoid saving and restroing FPSIMD registers until >> threads access

Re: [RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-27 Thread Will Deacon
On Fri, Sep 27, 2013 at 09:04:46AM +0100, Jiang Liu wrote: > From: Jiang Liu > > Use PF_USED_MATH flag to mark whether the thread has accessed any FPSIMD > registers, so we could avoid saving and restroing FPSIMD registers until > threads access them. This may improve performance when lazy

[RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-27 Thread Jiang Liu
From: Jiang Liu Use PF_USED_MATH flag to mark whether the thread has accessed any FPSIMD registers, so we could avoid saving and restroing FPSIMD registers until threads access them. This may improve performance when lazy FPSIMD restore is disabled. Signed-off-by: Jiang Liu Cc: Jiang Liu ---

[RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-27 Thread Jiang Liu
From: Jiang Liu jiang@huawei.com Use PF_USED_MATH flag to mark whether the thread has accessed any FPSIMD registers, so we could avoid saving and restroing FPSIMD registers until threads access them. This may improve performance when lazy FPSIMD restore is disabled. Signed-off-by: Jiang Liu

Re: [RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-27 Thread Will Deacon
On Fri, Sep 27, 2013 at 09:04:46AM +0100, Jiang Liu wrote: From: Jiang Liu jiang@huawei.com Use PF_USED_MATH flag to mark whether the thread has accessed any FPSIMD registers, so we could avoid saving and restroing FPSIMD registers until threads access them. This may improve performance

Re: [RFT PATCH v1 6/7] amd64: avoid saving and restoring FPSIMD registers until threads access them

2013-09-27 Thread Jiang Liu
On 09/27/2013 06:59 PM, Will Deacon wrote: On Fri, Sep 27, 2013 at 09:04:46AM +0100, Jiang Liu wrote: From: Jiang Liu jiang@huawei.com Use PF_USED_MATH flag to mark whether the thread has accessed any FPSIMD registers, so we could avoid saving and restroing FPSIMD registers until threads