On Mon, Feb 17, 2014 at 02:47:03PM -0800, H. Peter Anvin wrote: > On 02/17/2014 12:41 PM, Waiman Long wrote: > > v3->v4: > > - Remove debugging code and fix a configuration error > > - Simplify the qspinlock structure and streamline the code to make it > > perform a bit better > > - Add an x86 version of asm/qspinlock.h for holding x86 specific > > optimization. > > - Add an optimized x86 code path for 2 contending tasks to improve > > low contention performance. > > > > v2->v3: > > - Simplify the code by using numerous mode only without an unfair option. > > - Use the latest smp_load_acquire()/smp_store_release() barriers. > > - Move the queue spinlock code to kernel/locking. > > - Make the use of queue spinlock the default for x86-64 without user > > configuration. > > - Additional performance tuning. > > > > v1->v2: > > - Add some more comments to document what the code does. > > - Add a numerous CPU mode to support >= 16K CPUs > > - Add a configuration option to allow lock stealing which can further > > improve performance in many cases. > > - Enable wakeup of queue head CPU at unlock time for non-numerous > > CPU mode. > > > > This patch set introduces a queue-based spinlock implementation that > > can replace the default ticket spinlock without increasing the size > > of the spinlock data structure. As a result, critical kernel data > > structures that embed spinlock won't increase in size and breaking > > data alignments. > > > > This is starting to look good, so I have pulled it into > tip:x86/spinlocks to start give it some testing mileage. It very much needs paravirt muck before we can even consider it. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
