>>> On 06.02.18 at 02:07, <andrew.coop...@citrix.com> wrote: > On 05/02/2018 19:23, Konrad Rzeszutek Wilk wrote: >> On Mon, Feb 05, 2018 at 07:10:33PM +0000, Andrew Cooper wrote: >>> - apply_alternatives(__alt_instructions, __alt_instructions_end); >>> + /* Send ourselves an NMI to trigger the callback. */ >>> + self_nmi(); >>> + >>> + /* >>> + * Sending ourself an NMI isn't architecturally guaranteed to result in >>> + * the synchronous delivery (although in practice, it appears to be). >>> + * Poll alt_done for up to 1 second. >>> + */ >>> + for ( i = 0; !ACCESS_ONCE(alt_done) && i < 1000; ++i ) >> Perhaps an #define for this? > > I don't really see the point. I'm fairly sure that no 64bit CPU will > enter this loop, but the APIC spec doesn't guarantee that delivery is > synchronous.
I agree. If anything, the subsequent check could be changed from "i >= 1000" to "!ACCESS_ONCE(alt_done)", eliminating the double use of the same plain number. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
