Re: [Qemu-devel] [PATCH] target-arm: Implement WFE as a yield operation

2014-02-25 Thread Rob Herring
On Tue, Feb 25, 2014 at 8:45 AM, Peter Maydell wrote: > Implement WFE to yield our timeslice to the next CPU. > This avoids slowdowns in multicore configurations caused > by one core busy-waiting on a spinlock which can't possibly > be unlocked until the other core has an opportunity to run. > Thi

Re: [Qemu-devel] [PATCH] target-arm: Implement WFE as a yield operation

2014-02-25 Thread Richard Henderson
On 02/25/2014 06:45 AM, Peter Maydell wrote: > Implement WFE to yield our timeslice to the next CPU. > This avoids slowdowns in multicore configurations caused > by one core busy-waiting on a spinlock which can't possibly > be unlocked until the other core has an opportunity to run. > This speeds u

[Qemu-devel] [PATCH] target-arm: Implement WFE as a yield operation

2014-02-25 Thread Peter Maydell
Implement WFE to yield our timeslice to the next CPU. This avoids slowdowns in multicore configurations caused by one core busy-waiting on a spinlock which can't possibly be unlocked until the other core has an opportunity to run. This speeds up my test case A15 dual-core boot by a factor of three