[PATCH] Fix getdelays.c - cpumask length and error reporting

Fix the length passed while (un)registering cpumask.  We were passing sizeof
the array, make it strlen().

Error value printed in fatal errors should be derived from the message.  The
message contains an nlmsgerr embedded with an error value.  We must report
that value to the user.

Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jamal Hadi <hadi@cyberus.ca>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/accounting/getdelays.c

@@ -285,7 +285,7 @@ int main(int argc, char *argv[])
 	if (maskset) {
 		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 			      TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
-			      &cpumask, sizeof(cpumask));
+			      &cpumask, strlen(cpumask) + 1);
 		PRINTF("Sent register cpumask, retval %d\n", rc);
 		if (rc < 0) {
 			printf("error sending register cpumask\n");
@@ -315,7 +315,8 @@ int main(int argc, char *argv[])
 		}
 		if (msg.n.nlmsg_type == NLMSG_ERROR ||
 		    !NLMSG_OK((&msg.n), rep_len)) {
-			printf("fatal reply error,  errno %d\n", errno);
+			struct nlmsgerr *err = NLMSG_DATA(&msg);
+			printf("fatal reply error,  errno %d\n", err->error);
 			goto done;
 		}
 
@@ -383,7 +384,7 @@ int main(int argc, char *argv[])
 	if (maskset) {
 		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 			      TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
-			      &cpumask, sizeof(cpumask));
+			      &cpumask, strlen(cpumask) + 1);
 		printf("Sent deregister mask, retval %d\n", rc);
 		if (rc < 0)
 			err(rc, "error sending deregister cpumask\n");