Re: [PATCH v7 5/6] perf tools: Show memory region in perf-script subcommand

On Thu, Sep 10, 2026 at 10:22:53AM +0800, Mi, Dapeng wrote:

On 9/10/2026 12:02 AM, Thomas Falcon wrote:

quoted

From: Dapeng Mi <redacted>

Show the memory region in perf-script subcommand. Memory region is found
in the mem_region field of the memory information data source. This
field was included with the introduction of support for the Off-module
Response facility (OMR) [1] in Intel's Diamond Rapids and Nova Lake
Architectures.

An example of perf-script output with the new memory region field is shown
below:

random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2ec
random    2411a68201042 |OP LOAD|LVL RAM hit|SNP Hit|TLB L1 or L2 hit|LCK No|BLK  N/A|Region  Mem-1                          561de7f8910a
random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2d0
random      20e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  Data|Region  N/A                          7f32ae64a2d0
random      20e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  Data|Region  N/A                          7f32ae64a2d0
random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2ec
random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2d0
random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2d0
random    2411a68201042 |OP LOAD|LVL RAM hit|SNP Hit|TLB L1 or L2 hit|LCK No|BLK  N/A|Region  Mem-1                          561de7f8910a
random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2ec
random      10e6a100042 |OP LOAD|LVL L0 hit|SNP None|TLB L1 or L2 hit|LCK Yes|BLK  N/A|Region  N/A                           7f32ae64a2d0

[1]: https://lore.kernel.org/all/20260114011750.350569-1-dapeng1.mi@linux.intel.com/ (local)

Assisted-by: Sashiko:gemini-3.1-pro-preview
Assisted-by: GitHub-Copilot:claude-opus-4-8
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Dapeng Mi <redacted>

Add your "Co-developed-by" tag here. Thanks.

I'll wait for v8 then, ok?

- Arnaldo
 

quoted

Signed-off-by: Thomas Falcon <redacted>
---
v4: Drop the global show-region flag; pass perf_session to
    perf_script__meminfo_scnprintf() and gate the Region field
    on the feature bit, with a pipe-mode fallback

v3: make memory region reporting conditional on feature bit
---
 tools/perf/builtin-script.c                   | 13 +--
 tools/perf/util/mem-events.c                  | 86 ++++++++++++++++++-
 tools/perf/util/mem-events.h                  |  4 +-
 .../scripting-engines/trace-event-python.c    |  5 +-
 4 files changed, 98 insertions(+), 10 deletions(-)

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index ad8ca08ceb5f..c7454155038d 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c

@@ -2078,11 +2078,12 @@ static int evlist__max_name_len(struct evlist *evlist)
 	return max;
 }
 
-static int data_src__fprintf(u64 data_src, FILE *fp)
+static int data_src__fprintf(struct perf_session *session,
+			     u64 data_src, FILE *fp)
 {
 	struct mem_info *mi = mem_info__new();
-	char decode[100];
-	char out[100];
+	char decode[200];
+	char out[200];
 	static int maxlen;
 	int len;
 

@@ -2090,10 +2091,10 @@ static int data_src__fprintf(u64 data_src, FILE *fp)
 		return -ENOMEM;
 
 	mem_info__data_src(mi)->val = data_src;
-	perf_script__meminfo_scnprintf(decode, 100, mi);
+	perf_script__meminfo_scnprintf(decode, 200, mi, session);
 	mem_info__put(mi);
 
-	len = scnprintf(out, 100, "%16" PRIx64 " %s", data_src, decode);
+	len = scnprintf(out, 200, "%16" PRIx64 " %s", data_src, decode);
 	if (maxlen < len)
 		maxlen = len;
 

@@ -2487,7 +2488,7 @@ static void process_event(struct perf_script *script,
 		perf_sample__fprintf_addr(sample, thread, evsel, fp);
 
 	if (PRINT_FIELD(DATA_SRC))
-		data_src__fprintf(sample->data_src, fp);
+		data_src__fprintf(evsel__session(evsel), sample->data_src, fp);
 
 	if (PRINT_FIELD(WEIGHT))
 		fprintf(fp, "%16" PRIu64, sample->weight);

diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index 4fd48fd20055..8ce4996cad8d 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c

@@ -604,8 +604,77 @@ int perf_mem__blk_scnprintf(char *out, size_t sz, const struct mem_info *mem_inf
 	return l;
 }
 
-int perf_script__meminfo_scnprintf(char *out, size_t sz, const struct mem_info *mem_info)
+static int perf_mem__region_scnprintf(char *out, size_t sz, const struct mem_info *mem_info)
 {
+	size_t l = 0;
+	u64 mem = PERF_MEM_REGION_NA;
+
+	sz -= 1; /* -1 for null termination */
+	out[0] = '\0';
+
+	if (mem_info)
+		mem = mem_info__const_data_src(mem_info)->mem_region;
+
+	switch (mem) {
+	case PERF_MEM_REGION_NA:
+	case PERF_MEM_REGION_RSVD:
+		l += scnprintf(out + l, sz - l, "N/A");
+		break;
+	case PERF_MEM_REGION_L_SHARE:
+		l += scnprintf(out + l, sz - l, "Local-shared-cache");
+		break;
+	case PERF_MEM_REGION_L_NON_SHARE:
+		l += scnprintf(out + l, sz - l, "Local-non-shared-cache");
+		break;
+	case PERF_MEM_REGION_O_IO:
+		l += scnprintf(out + l, sz - l, "Other-IO");
+		break;
+	case PERF_MEM_REGION_O_SHARE:
+		l += scnprintf(out + l, sz - l, "Other-shared-cache");
+		break;
+	case PERF_MEM_REGION_O_NON_SHARE:
+		l += scnprintf(out + l, sz - l, "Other-non-shared-cache");
+		break;
+	case PERF_MEM_REGION_MMIO:
+		l += scnprintf(out + l, sz - l, "MMIO");
+		break;
+	case PERF_MEM_REGION_MEM0:
+		l += scnprintf(out + l, sz - l, "Mem-0");
+		break;
+	case PERF_MEM_REGION_MEM1:
+		l += scnprintf(out + l, sz - l, "Mem-1");
+		break;
+	case PERF_MEM_REGION_MEM2:
+		l += scnprintf(out + l, sz - l, "Mem-2");
+		break;
+	case PERF_MEM_REGION_MEM3:
+		l += scnprintf(out + l, sz - l, "Mem-3");
+		break;
+	case PERF_MEM_REGION_MEM4:
+		l += scnprintf(out + l, sz - l, "Mem-4");
+		break;
+	case PERF_MEM_REGION_MEM5:
+		l += scnprintf(out + l, sz - l, "Mem-5");
+		break;
+	case PERF_MEM_REGION_MEM6:
+		l += scnprintf(out + l, sz - l, "Mem-6");
+		break;
+	case PERF_MEM_REGION_MEM7:
+		l += scnprintf(out + l, sz - l, "Mem-7");
+		break;
+	default:
+		l += scnprintf(out + l, sz - l, "N/A");
+		break;
+	}
+
+	return l;
+}
+
+int perf_script__meminfo_scnprintf(char *out, size_t sz,
+				   const struct mem_info *mem_info,
+				   struct perf_session *session)
+{
+	struct perf_env *env;
 	int i = 0;
 
 	i += scnprintf(out, sz, "|OP ");

@@ -620,6 +689,21 @@ int perf_script__meminfo_scnprintf(char *out, size_t sz, const struct mem_info *
 	i += perf_mem__lck_scnprintf(out + i, sz - i, mem_info);
 	i += scnprintf(out + i, sz - i, "|BLK ");
 	i += perf_mem__blk_scnprintf(out + i, sz - i, mem_info);
+	if (session) {
+		/*
+		 * In case the feature bits are not available, as in
+		 * pipe mode, fallback to checking for the existence of
+		 * memory ranges
+		 */
+		env = perf_session__env(session);
+		if ((env && session->data->is_pipe && env->nr_memory_ranges) ||
+		    perf_header__has_feat(&session->header,
+					  HEADER_MEMORY_RANGES)) {
+			i += scnprintf(out + i, sz - i, "|Region ");
+			i += perf_mem__region_scnprintf(out + i, sz - i,
+							mem_info);
+		}
+	}
 
 	return i;
 }

diff --git a/tools/perf/util/mem-events.h b/tools/perf/util/mem-events.h
index daa22748f9fe..4ebb8109fc3c 100644
--- a/tools/perf/util/mem-events.h
+++ b/tools/perf/util/mem-events.h

@@ -4,6 +4,7 @@
 
 #include <stdbool.h>
 #include <linux/types.h>
+#include "session.h"
 
 struct perf_mem_event {
 	bool		supported;

@@ -47,7 +48,8 @@ int perf_mem__snp_scnprintf(char *out, size_t sz, const struct mem_info *mem_inf
 int perf_mem__lck_scnprintf(char *out, size_t sz, const struct mem_info *mem_info);
 int perf_mem__blk_scnprintf(char *out, size_t sz, const struct mem_info *mem_info);
 
-int perf_script__meminfo_scnprintf(char *bf, size_t size, const struct mem_info *mem_info);
+int perf_script__meminfo_scnprintf(char *bf, size_t size, const struct mem_info *mem_info,
+				   struct perf_session *session);
 
 struct c2c_stats {
 	u32	nr_entries;

diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index 8f832ae316ca..e359fe529586 100644
--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c

@@ -694,8 +694,9 @@ static void set_sample_read_in_dict(PyObject *dict_sample, struct perf_sample *s
 static void set_sample_datasrc_in_dict(PyObject *dict,
 				      struct perf_sample *sample)
 {
+	struct perf_session *session = evsel__session(sample->evsel);
 	struct mem_info *mi = mem_info__new();
-	char decode[100];
+	char decode[200];
 
 	if (!mi)
 		Py_FatalError("couldn't create mem-info");

@@ -704,7 +705,7 @@ static void set_sample_datasrc_in_dict(PyObject *dict,
 			PyLong_FromUnsignedLongLong(sample->data_src));
 
 	mem_info__data_src(mi)->val = sample->data_src;
-	perf_script__meminfo_scnprintf(decode, 100, mi);
+	perf_script__meminfo_scnprintf(decode, 200, mi, session);
 	mem_info__put(mi);
 
 	pydict_set_item_string_decref(dict, "datasrc_decode",