diff options
| author | Anton Blanchard <anton@samba.org> | 2009-10-26 18:50:29 (GMT) |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2009-10-28 05:13:04 (GMT) |
| commit | c8cd093a6e9f96ea6b871576fd4e46d7c818bb89 (patch) | |
| tree | 2bad2c3a2cc68a35fb93d986a49bf543efcd0156 /arch/powerpc/include/asm/hvcall.h | |
| parent | 6795b85c6a4f690e61e7be31aa150d945c723fb5 (diff) | |
| download | linux-c8cd093a6e9f96ea6b871576fd4e46d7c818bb89.tar.xz | |
powerpc: tracing: Add hypervisor call tracepoints
Add hcall_entry and hcall_exit tracepoints. This replaces the inline
assembly HCALL_STATS code and converts it to use the new tracepoints.
To keep the disabled case as quick as possible, we embed a status word
in the TOC so we can get at it with a single load. By doing so we
keep the overhead at a minimum. Time taken for a null hcall:
No tracepoint code: 135.79 cycles
Disabled tracepoints: 137.95 cycles
For reference, before this patch enabling HCALL_STATS resulted in a null
hcall of 201.44 cycles!
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/include/asm/hvcall.h')
| -rw-r--r-- | arch/powerpc/include/asm/hvcall.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index 6251a4b..c27caac 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -274,6 +274,8 @@ struct hcall_stats { unsigned long num_calls; /* number of calls (on this CPU) */ unsigned long tb_total; /* total wall time (mftb) of calls. */ unsigned long purr_total; /* total cpu time (PURR) of calls. */ + unsigned long tb_start; + unsigned long purr_start; }; #define HCALL_STAT_ARRAY_SIZE ((MAX_HCALL_OPCODE >> 2) + 1) |