| Message ID | 1487447914-7094-1-git-send-email-maddy@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Rejected |
| Headers | show |
On Sun, Feb 19, 2017 at 01:28:34AM +0530, Madhavan Srinivasan wrote: > From PowerISA v2.07, architecture provides a special NOP > instruction called "Probe-Nop" defined as "and 0,0,0". > This form of "and" is reserved for use exclusively by the > Performance Monitor. > > Usage example: > > Add PROBENOP() macro to __tlbie() in hash_native_64.c to > verify the number of TLBIE. Power8 provides "PM_TLBIE_FIN" > PMU event (r30058) to count "tlbie finished". > > Power8 PMU event "PM_PROBE_NOP_DISP" (r40014) counts the > "ProbeNops dispatched". > > With modified kernel booted, output from perf: > > # ./perf stat -e r30058,r40014 ls > .... > Performance counter stats for 'ls': > > 7 r30058 > 7 r40014 > > 0.003296959 seconds time elapsed > > Macro comes handy when want to count specific instructions > which may or may not have a PMU event. > > Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> > --- Acked-by: Balbir Singh <bsingharora@gmail.com>
diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h index c4ced1d01d57..61c62a1a402c 100644 --- a/arch/powerpc/include/asm/ppc-opcode.h +++ b/arch/powerpc/include/asm/ppc-opcode.h @@ -462,4 +462,14 @@ ((IH & 0x7) << 21)) #define PPC_INVALIDATE_ERAT PPC_SLBIA(7) +/* + * From PowerISA v2.07, architecture provides a special NOP instruction + * called "Probe-Nop" defined as "and 0,0,0". This form of "and" is + * reserved for use exclusively by the Performance Monitor. + */ +#define _PROBENOP(x) stringify_in_c(.long PPC_INST_AND | \ + ___PPC_RS(x) | \ + ___PPC_RA(x) | \ + ___PPC_RB(x)) +#define PROBENOP(x) asm volatile(_PROBENOP(x)) #endif /* _ASM_POWERPC_PPC_OPCODE_H */
From PowerISA v2.07, architecture provides a special NOP instruction called "Probe-Nop" defined as "and 0,0,0". This form of "and" is reserved for use exclusively by the Performance Monitor. Usage example: Add PROBENOP() macro to __tlbie() in hash_native_64.c to verify the number of TLBIE. Power8 provides "PM_TLBIE_FIN" PMU event (r30058) to count "tlbie finished". Power8 PMU event "PM_PROBE_NOP_DISP" (r40014) counts the "ProbeNops dispatched". With modified kernel booted, output from perf: # ./perf stat -e r30058,r40014 ls .... Performance counter stats for 'ls': 7 r30058 7 r40014 0.003296959 seconds time elapsed Macro comes handy when want to count specific instructions which may or may not have a PMU event. Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> --- arch/powerpc/include/asm/ppc-opcode.h | 10 ++++++++++ 1 file changed, 10 insertions(+)