summaryrefslogtreecommitdiff
path: root/Documentation
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/accounting/getdelays.c38
1 files changed, 36 insertions, 2 deletions
diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c
index 6e25c2659e0a..a2976a6de033 100644
--- a/Documentation/accounting/getdelays.c
+++ b/Documentation/accounting/getdelays.c
@@ -21,6 +21,7 @@
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
+#include <sys/wait.h>
#include <signal.h>
#include <linux/genetlink.h>
@@ -266,11 +267,13 @@ int main(int argc, char *argv[])
int containerset = 0;
char containerpath[1024];
int cfd = 0;
+ int forking = 0;
+ sigset_t sigset;
struct msgtemplate msg;
- while (1) {
- c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:");
+ while (!forking) {
+ c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");
if (c < 0)
break;
@@ -319,6 +322,28 @@ int main(int argc, char *argv[])
err(1, "Invalid pid\n");
cmd_type = TASKSTATS_CMD_ATTR_PID;
break;
+ case 'c':
+
+ /* Block SIGCHLD for sigwait() later */
+ if (sigemptyset(&sigset) == -1)
+ err(1, "Failed to empty sigset");
+ if (sigaddset(&sigset, SIGCHLD))
+ err(1, "Failed to set sigchld in sigset");
+ sigprocmask(SIG_BLOCK, &sigset, NULL);
+
+ /* fork/exec a child */
+ tid = fork();
+ if (tid < 0)
+ err(1, "Fork failed\n");
+ if (tid == 0)
+ if (execvp(argv[optind - 1],
+ &argv[optind - 1]) < 0)
+ exit(-1);
+
+ /* Set the command type and avoid further processing */
+ cmd_type = TASKSTATS_CMD_ATTR_PID;
+ forking = 1;
+ break;
case 'v':
printf("debug on\n");
dbg = 1;
@@ -370,6 +395,15 @@ int main(int argc, char *argv[])
goto err;
}
+ /*
+ * If we forked a child, wait for it to exit. Cannot use waitpid()
+ * as all the delicious data would be reaped as part of the wait
+ */
+ if (tid && forking) {
+ int sig_received;
+ sigwait(&sigset, &sig_received);
+ }
+
if (tid) {
rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
cmd_type, &tid, sizeof(__u32));