Author: rwatson
Date: Sat Apr 25 15:43:12 2015
New Revision: 281983
URL: https://svnweb.freebsd.org/changeset/base/281983
Log:
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
Modified:
head/sys/cddl/dev/profile/profile.c
Modified: head/sys/cddl/dev/profile/profile.c
==============================================================================
--- head/sys/cddl/dev/profile/profile.c Sat Apr 25 13:34:25 2015
(r281982)
+++ head/sys/cddl/dev/profile/profile.c Sat Apr 25 15:43:12 2015
(r281983)
@@ -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 {
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
