[PATCH 2/4] perf: Add mem_hops field in perf_mem_data_src structure
Kajol Jain
kjain at linux.ibm.com
Tue Oct 5 20:18:35 AEDT 2021
Going forward, future generation systems can have more hierarchy
within the chip/package level but currently we don't have any data source
encoding field in perf, which can be used to represent this level of data.
Add a new field called 'mem_hops' in the perf_mem_data_src structure
which can be used to represent intra-chip/package or inter-chip/off-package
details. This field is of size 3 bits where PERF_MEM_HOPS_{NA, 0..6} value
can be used to present different hop levels data.
Also add corresponding macros to define mem_hop field values
and shift value.
Currently we define macro for HOPS_0 which corresponds
to data coming from another core but same chip.
For ex: Encodings for mem_hops fields with L2 cache:
L2 - local L2
L2 | REMOTE | HOPS_0 - remote core, same chip L2
Signed-off-by: Kajol Jain <kjain at linux.ibm.com>
---
include/uapi/linux/perf_event.h | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index e1701e9c7858..42680563228c 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -1210,14 +1210,16 @@ union perf_mem_data_src {
mem_remote:1, /* remote */
mem_snoopx:2, /* snoop mode, ext */
mem_blk:3, /* access blocked */
- mem_rsvd:21;
+ mem_hops:3, /* hop level */
+ mem_rsvd:18;
};
};
#elif defined(__BIG_ENDIAN_BITFIELD)
union perf_mem_data_src {
__u64 val;
struct {
- __u64 mem_rsvd:21,
+ __u64 mem_rsvd:18,
+ mem_hops:3, /* hop level */
mem_blk:3, /* access blocked */
mem_snoopx:2, /* snoop mode, ext */
mem_remote:1, /* remote */
@@ -1313,6 +1315,11 @@ union perf_mem_data_src {
#define PERF_MEM_BLK_ADDR 0x04 /* address conflict */
#define PERF_MEM_BLK_SHIFT 40
+/* hop level */
+#define PERF_MEM_HOPS_0 0x01 /* remote core, same chip */
+/* 2-7 available */
+#define PERF_MEM_HOPS_SHIFT 43
+
#define PERF_MEM_S(a, s) \
(((__u64)PERF_MEM_##a##_##s) << PERF_MEM_##a##_SHIFT)
--
2.26.2
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