Re: svn commit: r313996 - in head/sys: kern sys

2017-02-23 Thread Mateusz Guzik
On Wed, Feb 22, 2017 at 03:09:24PM -0800, Gleb Smirnoff wrote: > Mateusz, > > why do you __predict_false() the recursion scenario? I'm afraid > that performance loss for mispredictions could outweight the > gain due to predictions. AFAIK, mutex recursion is still a pretty > common event in

Re: svn commit: r313996 - in head/sys: kern sys

2017-02-22 Thread Gleb Smirnoff
Mateusz, why do you __predict_false() the recursion scenario? I'm afraid that performance loss for mispredictions could outweight the gain due to predictions. AFAIK, mutex recursion is still a pretty common event in the kernel. On Mon, Feb 20, 2017 at 07:08:36PM +, Mateusz Guzik wrote:

svn commit: r313996 - in head/sys: kern sys

2017-02-20 Thread Mateusz Guzik
Author: mjg Date: Mon Feb 20 19:08:36 2017 New Revision: 313996 URL: https://svnweb.freebsd.org/changeset/base/313996 Log: mtx: fix spin mutexes interaction with failed fcmpset While doing so move recursion support down to the fallback routine. Modified: head/sys/kern/kern_mutex.c