lkml.org 
[lkml]   [2013]   [Jun]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/5] perf: fix broken union in perf_event_mmap_page
On Fri, Jun 28, 2013 at 04:22:17PM +0300, Adrian Hunter wrote:
> The capabilities bits must not be "union'ed" together.
> Put them in a separate struct.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
> include/uapi/linux/perf_event.h | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> index 0b1df41..19f6ee5 100644
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -375,9 +375,11 @@ struct perf_event_mmap_page {
> __u64 time_running; /* time event on cpu */
> union {
> __u64 capabilities;
> - __u64 cap_usr_time : 1,
> - cap_usr_rdpmc : 1,
> - cap_____res : 62;
> + struct {
> + __u64 cap_usr_time : 1,
> + cap_usr_rdpmc : 1,
> + cap_____res : 62;
> + };
> };

Ick, it did that!? and here I thought there was a difference between:

int foo:1,
bar:1;

and

int foo:1;
int bar:1;

That made all the difference in this particular case. I guess I should
go read the language spec more carefully next time.


\
 
 \ /
  Last update: 2013-06-28 17:41    [W:0.164 / U:6.244 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site