Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Mathieu Desnoyers
- On Jan 5, 2016, at 12:31 PM, Mathieu Desnoyers mathieu.desnoy...@efficios.com wrote: > - On Jan 5, 2016, at 7:04 AM, Will Deacon will.dea...@arm.com wrote: > >> Hi Mathieu, >> >> On Tue, Jan 05, 2016 at 02:01:58AM -0500, Mathieu Desnoyers wrote: >>> Expose a new system call allowing

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Mathieu Desnoyers
- On Jan 5, 2016, at 7:04 AM, Will Deacon will.dea...@arm.com wrote: > Hi Mathieu, > > On Tue, Jan 05, 2016 at 02:01:58AM -0500, Mathieu Desnoyers wrote: >> Expose a new system call allowing threads to register userspace memory >> areas where to store the CPU number on which the calling

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Russell King - ARM Linux
On Tue, Jan 05, 2016 at 05:31:45PM +, Mathieu Desnoyers wrote: > For instance, an application could create a linked list or hash map > of thread control structures, which could contain the current CPU > number of each thread. A dispatch thread could then traverse or > lookup this structure to

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Mathieu Desnoyers
- On Jan 5, 2016, at 12:40 PM, Russell King - ARM Linux li...@arm.linux.org.uk wrote: > On Tue, Jan 05, 2016 at 05:31:45PM +, Mathieu Desnoyers wrote: >> For instance, an application could create a linked list or hash map >> of thread control structures, which could contain the current

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Paul E. McKenney
On Tue, Jan 05, 2016 at 10:34:04PM +, Mathieu Desnoyers wrote: > - On Jan 5, 2016, at 4:47 PM, Paul E. McKenney paul...@linux.vnet.ibm.com > wrote: > > > On Tue, Jan 05, 2016 at 05:40:18PM +, Russell King - ARM Linux wrote: > >> On Tue, Jan 05, 2016 at 05:31:45PM +, Mathieu

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Mathieu Desnoyers
- On Jan 5, 2016, at 4:47 PM, Paul E. McKenney paul...@linux.vnet.ibm.com wrote: > On Tue, Jan 05, 2016 at 05:40:18PM +, Russell King - ARM Linux wrote: >> On Tue, Jan 05, 2016 at 05:31:45PM +, Mathieu Desnoyers wrote: >> > For instance, an application could create a linked list or

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Paul E. McKenney
On Tue, Jan 05, 2016 at 05:40:18PM +, Russell King - ARM Linux wrote: > On Tue, Jan 05, 2016 at 05:31:45PM +, Mathieu Desnoyers wrote: > > For instance, an application could create a linked list or hash map > > of thread control structures, which could contain the current CPU > > number of

Re: [RFC PATCH 1/3] getcpu_cache system call: cache CPU number of running thread

2016-01-05 Thread Will Deacon
Hi Mathieu, On Tue, Jan 05, 2016 at 02:01:58AM -0500, Mathieu Desnoyers wrote: > Expose a new system call allowing threads to register userspace memory > areas where to store the CPU number on which the calling thread is > running. Scheduler migration sets the TIF_NOTIFY_RESUME flag on the >