On 04.11.2019 01:02, Konstantin Belousov wrote: > On Sun, Nov 03, 2019 at 09:17:51PM +0000, Vladimir Kondratyev wrote: >> Author: wulf >> Date: Sun Nov 3 21:17:50 2019 >> New Revision: 354322 >> URL: https://svnweb.freebsd.org/changeset/base/354322 >> >> Log: >> [ig4] Convert ithread interrupt handler to filter based one. > And why ? > > You need some reason to use filters/spinlocks, otherwise it only > taxes system latency.
The only thing ig4 interrupt handler does is a waking up the user thread, so postponing it to ithread looks like a wasting of CPU cycles. Spinlock here is acting as condition variable not as a data protection lock. It is taken around msleep(). I can replace it with cv_* calls if current usage confuses someone Ig4 access is serialized with sx lock so it is impossible to get any congestion on spinlock _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
