diff options
| author | Robert Watson <rwatson@FreeBSD.org> | 2015-04-25 15:43:12 +0000 |
|---|---|---|
| committer | Robert Watson <rwatson@FreeBSD.org> | 2015-04-25 15:43:12 +0000 |
| commit | a12df97ed28e5bd5d4bf03c02f0a4848aaf6c94b (patch) | |
| tree | 58c2ec14c866a74ab8f633d95a534e588921b663 /sys/cddl/dev/profile | |
| parent | cad3cc1310cdc692c4261e36f5978bbbbcefd16b (diff) | |
Adjust PROF_ARTIFICIAL_FRAMES in the DTrace profile provider on ARM to
skip 10, rather than 9, frames. This appears to work quite well in
practice on the BeagleBone Black, so remove a comment about the value
being bogus and replace it with a slightly less negative one. However,
the number of frames to skip is quite sensitive to details of the timer
and interrupt handling paths, so this is necessarily fragile -- but no
more so than on x86.
Sponsored by: DARPA, AFRL
Notes
Notes:
svn path=/head/; revision=281983
Diffstat (limited to 'sys/cddl/dev/profile')
| -rw-r--r-- | sys/cddl/dev/profile/profile.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/sys/cddl/dev/profile/profile.c b/sys/cddl/dev/profile/profile.c index 338a95843913..d31d5c81077e 100644 --- a/sys/cddl/dev/profile/profile.c +++ b/sys/cddl/dev/profile/profile.c @@ -134,8 +134,10 @@ struct profile_probe_percpu; #endif #ifdef __arm__ -/* bogus */ -#define PROF_ARTIFICIAL_FRAMES 9 +/* + * At least on ARMv7, this appears to work quite well. + */ +#define PROF_ARTIFICIAL_FRAMES 10 #endif typedef struct profile_probe { |