On 11/10/26 7:17 AM, Matt Turner wrote:
mpc7450_threshold_use() reports event 0x30d (PMC3 select 13, FPR issue
queue entries) as using MMCR0[THRESHOLD], and the comment above it marks
the event with a question mark. The manual (MPC7450UM Rev. 5, Table
11-11) says the event counts the valid FPR issue queue entries each
cycle, with no threshold. PMC3 select 12, the GPR rename buffer event
next to it, is the one that uses the threshold.
The only effect is that r30d cannot be counted together with a threshold
event that uses a different threshold. Drop it from the list.
Fixes: 7325927e5a20 ("perf_counter: powerpc: Add processor back-end for MPC7450
family")
Signed-off-by: Matt Turner <[email protected]>
Hi Matt,
I checked Table 11-11 in the manual: PMC3 select 13 (0x30d) counts valid
FPR issue queue entries every cycle and has no threshold. On PMC3 only
select 12 (0x30c) and select 17 (0x311) use MMCR0[THRESHOLD]. That
matches with the code change.
Reviewed-by: Tanushree Shah <[email protected]>
Thanks
Tanushree Shah
---
arch/powerpc/perf/mpc7450-pmu.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/powerpc/perf/mpc7450-pmu.c b/arch/powerpc/perf/mpc7450-pmu.c
index db451b9aac35..564f6dac3a00 100644
--- a/arch/powerpc/perf/mpc7450-pmu.c
+++ b/arch/powerpc/perf/mpc7450-pmu.c
@@ -65,7 +65,6 @@ static int mpc7450_classify_event(u32 event)
* 12b Y PM_LD_MISS_EXCEED_L1_CYC
* 220 N PM_CQ_EXCEED_CYC
* 30c N PM_GPR_RB_EXCEED_CYC
- * 30d ? PM_FPR_IQ_EXCEED_CYC ?
* 311 Y PM_ITLB_SEARCH_EXCEED
* 410 N PM_GPR_IQ_EXCEED_CYC
*/
@@ -92,7 +91,7 @@ static int mpc7450_threshold_use(u32 event)
return 1;
break;
case 3:
- if (sel == 0xc || sel == 0xd)
+ if (sel == 0xc)
return 1;
if (sel == 0x11)
return 2;
