David,
just found your patch...
On 20.07.12 17:25:53, David Ahern wrote:
> PEBS cannot be used with guest mode. If user adds :p modifier set
> exclude_guest as well.
> @@ -653,6 +653,9 @@ int parse_events_modifier(struct list_head *list, char
> *str)
> eH = 0;
> } else if (*str == 'p') {
> precise++;
> + /* use of precise requires exclude_guest */
> + if (!exclude_GH)
> + eG = 1;
We should only enable exclude_guest if no G/H modifiers are given on
the command line. If I correctly read the code this is indicated by
exclude_GH and correctly implemented.
To summarize how I think it should work:
-e cycles:p ..... Enable exclude_guest bit. If the syscall fails,
fall back by disabling the guest bit and send
syscall again
-e cycles:pGH ... Do not enable exclude_guest/_host. Do not fall back
on syscall errors.
Same for the case the p modifier is not set.
So we have the following:
G ... set exclude_host bit, clear exclude_guest
H ... set exclude_guest bit, clear exclude_host
GH ... clear both exclude_guest/_host
<no G or H> ... default (set exclude_host bit, clear exclude_guest),
but fall back on syscall errors to clear both
exclude_guest/_host
The modifier parser should be correctly implemented and should work
with ibs. Will test this patch.
-Robert
--
Advanced Micro Devices, Inc.
Operating System Research Center
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