Date: Tue, 16 Oct 2007 10:39:28 -0700 From: Jason Evans <jasone@freebsd.org> To: Kris Kennaway <kris@FreeBSD.org> Cc: cvs-src@FreeBSD.org, src-committers@FreeBSD.org, David Xu <davidxu@FreeBSD.org>, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/lib/libthr/thread thr_pspinlock.c Message-ID: <4714F750.9010804@freebsd.org> In-Reply-To: <471480AB.7090500@FreeBSD.org> References: <200710160736.l9G7a3oI087966@repoman.freebsd.org> <471480AB.7090500@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
Kris Kennaway wrote: > David Xu wrote: >> FreeBSD src repository >> >> Modified files: >> lib/libthr/thread thr_pspinlock.c Log: >> Reverse the logic of UP and SMP. >> Submitted by: jasone >> Revision Changes Path >> 1.6 +1 -1 src/lib/libthr/thread/thr_pspinlock.c > > Are there any common applications that use this? It's worth mentioning that this change, although correct, does not make a measurable performance difference for the tests I was running when I found the bug. It is possible that making the spinlocks adaptive would help, but I didn't look into this. (I was working on malloc performance enhancements that have turned out very nicely, but in the end I had to switch to hand-rolled "spin" mutexes that eventually convert to blocking, in order to avoid the possibility of unrecoverable priority inversion.) Jason
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4714F750.9010804>