Re: [PATCH v7 4/6] selftests/resctrl: Cleanup properly when an error occurs in CAT test

Hi Shaopeng,

On 2/12/2023 10:24 PM, Shaopeng Tan wrote:

After creating a child process with fork() in CAT test, if an error occurs when parent process runs cat_val() or check_results(), the child process will not be killed and also resctrlfs is not unmounted. Also if an error occurs when child process runs cat_val() or check_results(), the child process is returned, but the parent process will wait pipe

"child process is returned" -> "child process returns"

message from child.

"will wait pipe message from child" -> "will wait for the pipe message from the child"

Synchronize the exits between the parent and child. An error occurs whether in parents process or child process, the parents process always kills child process and runs umount_resctrlfs(), and the child process always waits to be killed by the parent process.

I think the above could be easier to read with a few slight changes:

" Synchronize the exits between the parent and child. An error could occur whether in parent process or child process. The parent process always kills the child process and runs umount_resctrlfs(). The child process always waits to be killed by the parent process."

Signed-off-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com

tools/testing/selftests/resctrl/cat_test.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index 6a8306b0a109..477b62dac546 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -186,23 +186,20 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) remove(param.filename); ret = cat_val(&param);

• if (ret)

• return ret;
  

• ret = check_results(&param);
• if (ret)

• return ret;
  

• if (ret == 0)

• ret = check_results(&param);
  

if (bm_pid == 0) { /* Tell parent that child is ready */ close(pipefd[0]); pipe_message = 1; if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <

•     sizeof(pipe_message)) {
  

• 	close(pipefd[1]);
  

•     sizeof(pipe_message))
  

• 	/*
  

• 	 * Just print the error message.
  

• 	 * Let while(1) run and wait for itself to be killed.
  

• 	 */
  perror("# failed signaling parent process");
  

• 	return errno;
  

• }
  

close(pipefd[1]); while (1) @@ -226,5 +223,5 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) if (bm_pid) umount_resctrlfs();

• return 0;

• return ret;

}

Apart from the changelog comments:

Reviewed-by: Reinette Chatre reinette.chatre@intel.com

Thank you very much

Reinette