| Message ID | 20220914015147.3071025-6-tan.shaopeng@jp.fujitsu.com |
|---|---|
| State | New |
| Headers | show |
| Series | selftests/resctrl: Some improvements of resctrl selftest | expand |
Hi Shaopeng, On 9/13/2022 6:51 PM, Shaopeng Tan wrote: ... > @@ -218,11 +219,11 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) > } > } > close(pipefd[0]); > - kill(bm_pid, SIGKILL); > } > > - if (bm_pid) > - umount_resctrlfs(); > +out: > + kill(bm_pid, SIGKILL); > + umount_resctrlfs(); >
Hi Reinette, > On 9/13/2022 6:51 PM, Shaopeng Tan wrote: > > ... > > > @@ -218,11 +219,11 @@ int cat_perf_miss_val(int cpu_no, int n, char > *cache_type) > > } > > } > > close(pipefd[0]); > > - kill(bm_pid, SIGKILL); > > } > > > > - if (bm_pid) > > - umount_resctrlfs(); > > +out: > > + kill(bm_pid, SIGKILL); > > + umount_resctrlfs(); > > > > From what I can tell both parent and child will now run this code. So both will > attempt to unmount resctrl fs and the child will attempt to kill PID 0? Thanks for your advice. There are problems as you point out. I think it is complicated if we fix this bug like MBM/MBA/CMT test using sigaction(). It seems this bug cannot be solved easily. Please give me some time. Best Regards, Shaopeng
diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index d1134f66469f..f62da445acbb 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -186,11 +186,11 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) ret = cat_val(¶m); if (ret) - return ret; + goto out; ret = check_results(¶m); if (ret) - return ret; + goto out; if (bm_pid == 0) { /* Tell parent that child is ready */ @@ -200,7 +200,8 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) sizeof(pipe_message)) { close(pipefd[1]); perror("# failed signaling parent process"); - return errno; + ret = errno; + goto out; } close(pipefd[1]); @@ -218,11 +219,11 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) } } close(pipefd[0]); - kill(bm_pid, SIGKILL); } - if (bm_pid) - umount_resctrlfs(); +out: + kill(bm_pid, SIGKILL); + umount_resctrlfs(); - return 0; + return ret; }
After creating a child process with fork() in CAT test, if there is an exception occurs, the parent process will be terminated immediately, but the child process will not be killed and umount_resctrlfs() will not be called. When fork() is used in CMT/MBA/MBM tests. If an exception occurs, before parent process exiting, the child process is killed and umount_resctrlfs() is called. Kill the child process before exiting the parent process if an exception occurs in CAT test, like in CMT/MBA/MBM tests. Signed-off-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> --- tools/testing/selftests/resctrl/cat_test.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-)