# \[PATCH v15 12/19\] perf, tools: Add override support for event list CPUID

- From: Sukadev Bhattiprolu \<hidden\>
- Date: 2015-06-10 07:26:58 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2015/06/4512671
- Thread: https://ratatoskr.run/linuxppc-dev/2015/06/4512659/t.md

```text
From: Andi Kleen <redacted>

Add a PERF_CPUID variable to override the CPUID of the current CPU (within
the current architecture). This is useful for testing, so that all event
lists can be tested on a single system.

Signed-off-by: Andi Kleen <redacted>
Signed-off-by: Sukadev Bhattiprolu <redacted>
Acked-by: Jiri Olsa <redacted>
---

v2: Fix double free in earlier version.
    Print actual CPUID being used with verbose option.
---
 tools/perf/util/pmu.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index ebbd4c7..2a7abac 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -477,10 +477,16 @@ static int pmu_add_cpu_aliases(struct list_head *head)
 	struct pmu_event *pe;
 	char *cpuid;
 
-	cpuid = get_cpuid_str();
+	cpuid = getenv("PERF_CPUID");
+	if (cpuid)
+		cpuid = strdup(cpuid);
+	if (!cpuid)
+		cpuid = get_cpuid_str();
 	if (!cpuid)
 		return 0;
 
+	pr_debug("Using CPUID %s\n", cpuid);
+
 	i = 0;
 	while (1) {
 		map = &pmu_events_map[i++];
-- 
1.8.3.1
```