Re: [PATCH v2] cpupower: monitor: Exit with error status if execvp() fail

From: Shuah Khan
Date: Thu Feb 20 2025 - 11:35:29 EST


On 2/20/25 06:05, Yiwei Lin wrote:
In the case that we give a invalid command to idle_monitor for
monitoring, the execvp() will fail and thus go to the next line.
As a result, we'll see two differnt monitoring output. For
example, running `cpupower monitor -i 5 invalidcmd` which `invalidcmd`
is not executable.

---
V2:
- fix according to review from Shuah
---

Signed-off-by: Yiwei Lin <s921975628@xxxxxxxxx>
---
tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c
index f746099b5dac..7f8958f68eaa 100644
--- a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c
+++ b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c
@@ -6,6 +6,7 @@
*/
+#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
@@ -294,7 +295,10 @@ int fork_it(char **argv)
if (!child_pid) {
/* child */
- execvp(argv[0], argv);
+ if (execvp(argv[0], argv) == -1) {
+ printf("Fail to execute %s\n", argv[0]);

Invalid monitor command will be a better message than
saying "failed to execute"

thanks,
-- Shuahg