On 11/3/10 10:17 AM, John Baldwin wrote:
On Wednesday, November 03, 2010 1:04:13 pm m...@freebsd.org wrote:

So a MTX_DEF is okay in that environment?
Yes.  In fact, the reason to have threads for interrupt handlers is to allow
interrupt handlers to use non-spin locks that block when the lock is held.

MTX_SPIN locks are generally not needed in device drivers.  The only reason a
driver would use one is if it used a filter handler which does not run in a
threaded context.

It should be noted that in the case where you really just want to spin a few
instructions because some other thread is accessing a structure you want,
descheduling you. so you don't always incur the scheduling overhead.

_______________________________________________
freebsd-current@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-current
To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"

Reply via email to