Commit 20dd4c624d251 ('powerpc/perf: Fix SDAR_MODE value for continous
sampling on Power9') set the default sdar_mode value in MMCRA[SDAR_MODE]
to be used as 0b01 (Update on TLB miss). And this value is set if sdar_mode
from event is zero, or we are in continous sampling mode in power9 dd1.

But it is preferred to have the sdar_mode value for power9 as
0b10 (Update on dcache miss) for better sampling updates instead
of 0b01 (Update on TLB miss).

Signed-off-by: Madhavan Srinivasan <ma...@linux.vnet.ibm.com>
---
 arch/powerpc/perf/isa207-common.c | 2 +-
 arch/powerpc/perf/isa207-common.h | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/perf/isa207-common.c 
b/arch/powerpc/perf/isa207-common.c
index 3f3aa9a7063a..582ed2c9bc56 100644
--- a/arch/powerpc/perf/isa207-common.c
+++ b/arch/powerpc/perf/isa207-common.c
@@ -99,7 +99,7 @@ static void mmcra_sdar_mode(u64 event, unsigned long *mmcra)
                else if (!cpu_has_feature(CPU_FTR_POWER9_DD1) && 
p9_SDAR_MODE(event))
                        *mmcra |=  p9_SDAR_MODE(event) << MMCRA_SDAR_MODE_SHIFT;
                else
-                       *mmcra |= MMCRA_SDAR_MODE_TLB;
+                       *mmcra |= MMCRA_SDAR_MODE_DCACHE;
        } else
                *mmcra |= MMCRA_SDAR_MODE_TLB;
 }
diff --git a/arch/powerpc/perf/isa207-common.h 
b/arch/powerpc/perf/isa207-common.h
index 8acbe6e802c7..7a0228bf283c 100644
--- a/arch/powerpc/perf/isa207-common.h
+++ b/arch/powerpc/perf/isa207-common.h
@@ -247,6 +247,7 @@
 #define MMCRA_SDAR_MODE_SHIFT          42
 #define MMCRA_SDAR_MODE_TLB            (1ull << MMCRA_SDAR_MODE_SHIFT)
 #define MMCRA_SDAR_MODE_NO_UPDATES     ~(0x3ull << MMCRA_SDAR_MODE_SHIFT)
+#define MMCRA_SDAR_MODE_DCACHE         (2ull << MMCRA_SDAR_MODE_SHIFT)
 #define MMCRA_IFM_SHIFT                        30
 #define MMCRA_THR_CTR_MANT_SHIFT       19
 #define MMCRA_THR_CTR_MANT_MASK                0x7Ful
-- 
2.7.4

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