Re: [PATCH 0/2] arm64: Only call into preempt_schedule() if need_resched()

2018-11-28 Thread Will Deacon
On Wed, Nov 28, 2018 at 10:01:46AM +0100, Peter Zijlstra wrote: > On Wed, Nov 28, 2018 at 09:56:40AM +0100, Peter Zijlstra wrote: > > On Tue, Nov 27, 2018 at 07:45:00PM +, Will Deacon wrote: > > > This pair of patches improves our preempt_enable() implementation slightly > > > on arm64 by

Re: [PATCH 0/2] arm64: Only call into preempt_schedule() if need_resched()

2018-11-28 Thread Will Deacon
On Wed, Nov 28, 2018 at 10:01:46AM +0100, Peter Zijlstra wrote: > On Wed, Nov 28, 2018 at 09:56:40AM +0100, Peter Zijlstra wrote: > > On Tue, Nov 27, 2018 at 07:45:00PM +, Will Deacon wrote: > > > This pair of patches improves our preempt_enable() implementation slightly > > > on arm64 by

Re: [PATCH 0/2] arm64: Only call into preempt_schedule() if need_resched()

2018-11-28 Thread Peter Zijlstra
On Wed, Nov 28, 2018 at 09:56:40AM +0100, Peter Zijlstra wrote: > On Tue, Nov 27, 2018 at 07:45:00PM +, Will Deacon wrote: > > Hi all, > > > > This pair of patches improves our preempt_enable() implementation slightly > > on arm64 by making the resulting call to preempt_schedule() conditional

Re: [PATCH 0/2] arm64: Only call into preempt_schedule() if need_resched()

2018-11-28 Thread Peter Zijlstra
On Wed, Nov 28, 2018 at 09:56:40AM +0100, Peter Zijlstra wrote: > On Tue, Nov 27, 2018 at 07:45:00PM +, Will Deacon wrote: > > Hi all, > > > > This pair of patches improves our preempt_enable() implementation slightly > > on arm64 by making the resulting call to preempt_schedule() conditional

Re: [PATCH 0/2] arm64: Only call into preempt_schedule() if need_resched()

2018-11-28 Thread Peter Zijlstra
On Tue, Nov 27, 2018 at 07:45:00PM +, Will Deacon wrote: > Hi all, > > This pair of patches improves our preempt_enable() implementation slightly > on arm64 by making the resulting call to preempt_schedule() conditional > on need_resched(), which is tracked in bit 32 of the preempt count. The

Re: [PATCH 0/2] arm64: Only call into preempt_schedule() if need_resched()

2018-11-28 Thread Peter Zijlstra
On Tue, Nov 27, 2018 at 07:45:00PM +, Will Deacon wrote: > Hi all, > > This pair of patches improves our preempt_enable() implementation slightly > on arm64 by making the resulting call to preempt_schedule() conditional > on need_resched(), which is tracked in bit 32 of the preempt count. The