Re: [Patch][RFC] Disabling per-tgid stats on task exit in taskstats

Index: linux-2.6.17-mm3equiv/kernel/taskstats.c
===================================================================

--- linux-2.6.17-mm3equiv.orig/kernel/taskstats.c	2006-06-30 11:57:14.000000000 -0400
+++ linux-2.6.17-mm3equiv/kernel/taskstats.c	2006-06-30 13:58:36.000000000 -0400

@@ -266,7 +266,7 @@ void taskstats_exit_send(struct task_str
 	struct sk_buff *rep_skb;
 	void *reply;
 	size_t size;
-	int is_thread_group;
+	int is_thread_group, setid;
 	struct nlattr *na;

 	if (!family_registered || !tidstats)

@@ -320,7 +320,8 @@ void taskstats_exit_send(struct task_str
 	nla_nest_end(rep_skb, na);

 send:
-	send_reply(rep_skb, 0, TASKSTATS_MSG_MULTICAST);
+	setid = (smp_processor_id()%TASKSTATS_CPUS_PER_SET)+1;
+	send_reply(rep_skb, setid, TASKSTATS_MSG_MULTICAST);

 	return;

 nla_put_failure:
Index: linux-2.6.17-mm3equiv/Documentation/accounting/getdelays.c
===================================================================

--- linux-2.6.17-mm3equiv.orig/Documentation/accounting/getdelays.c	2006-06-28 16:08:56.000000000 -0400
+++ linux-2.6.17-mm3equiv/Documentation/accounting/getdelays.c	2006-06-30 14:09:28.000000000 -0400

@@ -40,7 +40,7 @@ int done = 0;
 /*
  * Create a raw netlink socket and bind
  */
-static int create_nl_socket(int protocol, int groups)
+static int create_nl_socket(int protocol, int cpugroup)
 {
     socklen_t addr_len;
     int fd;

@@ -52,7 +52,8 @@ static int create_nl_socket(int protocol

     memset(&local, 0, sizeof(local));
     local.nl_family = AF_NETLINK;
-    local.nl_groups = groups;
+    local.nl_groups = TASKSTATS_LISTEN_GROUP;
+    local.nl_pid = cpugroup;

     if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0)
 	goto error;

@@ -203,7 +204,7 @@ int main(int argc, char *argv[])
     pid_t rtid = 0;
     int cmd_type = TASKSTATS_TYPE_TGID;
     int c, status;
-    int forking = 0;
+    int forking = 0, cpugroup = 0;
     struct sigaction act = {
 	.sa_handler = SIG_IGN,
 	.sa_mask = SA_NOMASK,

@@ -222,7 +223,7 @@ int main(int argc, char *argv[])

     while (1) {

-	c = getopt(argc, argv, "t:p:c:");
+	c = getopt(argc, argv, "t:p:c:g:l");
 	if (c < 0)
 	    break;

@@ -252,8 +253,14 @@ int main(int argc, char *argv[])
 	    }
 	    forking = 1;
 	    break;
+	case 'g':
+		cpugroup = atoi(optarg);
+		break;
+	case 'l':
+		loop = 1;
+		break;
 	default:
-	    printf("usage %s [-t tgid][-p pid][-c cmd]\n", argv[0]);
+	    printf("usage %s [-t tgid][-p pid][-c cmd][-g cpugroup][-l]\n", argv[0]);
 	    exit(-1);
 	    break;
 	}

@@ -266,7 +273,7 @@ int main(int argc, char *argv[])
     /* Send Netlink request message & get reply */

     if ((nl_sd =
-	 create_nl_socket(NETLINK_GENERIC, TASKSTATS_LISTEN_GROUP)) < 0)
+	 create_nl_socket(NETLINK_GENERIC, cpugroup)) < 0)
 	err(1, "error creating Netlink socket\n");

@@ -287,10 +294,10 @@ int main(int argc, char *argv[])


     if (!forking && sendto_fd(nl_sd, (char *) &req, req.n.nlmsg_len) < 0)
+    if ((!forking && !loop) &&
+	sendto_fd(nl_sd, (char *) &req, req.n.nlmsg_len) < 0)
 	err(1, "error sending message via Netlink\n");

-    act.sa_handler = SIG_IGN;
-    sigemptyset(&act.sa_mask);
     if (sigaction(SIGINT, &act, NULL) < 0)
 	err(1, "sigaction failed for SIGINT\n");

@@ -349,10 +356,11 @@ int main(int argc, char *argv[])
 			rtid = *(int *) NLA_DATA(na);
 			break;
 		    case TASKSTATS_TYPE_STATS:
-			if (rtid == tid) {
+			if (rtid == tid || loop) {
 			    print_taskstats((struct taskstats *)
 					    NLA_DATA(na));
-			    done = 1;
+			    if (!loop)
+				    done = 1;
 			}
 			break;
 		    }

@@ -369,7 +377,7 @@ int main(int argc, char *argv[])
 	if (done)
 	    break;
     }
-    while (1);
+    while (loop);

     close(nl_sd);
     return 0;