From: compudj <compudj@04897980-b3bd-0310-b5e0-8ef037075253>
Date: Tue, 7 Mar 2006 18:47:27 +0000 (+0000)
Subject: usertrace fast work
X-Git-Tag: v0.12.20~1881
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=e8efa18da8bfbc203c0ed0eaf557dc280ff23daf;p=lttv.git

usertrace fast work

git-svn-id: http://ltt.polymtl.ca/svn@1608 04897980-b3bd-0310-b5e0-8ef037075253
---

diff --git a/usertrace-fast/ltt-usertrace-fast.c b/usertrace-fast/ltt-usertrace-fast.c
index cb131695..2a4f039e 100644
--- a/usertrace-fast/ltt-usertrace-fast.c
+++ b/usertrace-fast/ltt-usertrace-fast.c
@@ -50,82 +50,115 @@
 
 #include "ltt-usertrace-fast.h"
 
-/* TLS for the trace buffer
- * http://www.dis.com/gnu/gcc/C--98-Thread-Local-Edits.html
- *
- * Add after paragraph 4
- *
- *     The storage for an object of thread storage duration shall be statically
- *     initialized before the first statement of the thread startup function. An
- *     object of thread storage duration shall not require dynamic
- *     initialization.
- */
-#if 0
-__thread struct ltt_trace_info ltt_trace_info =
-{
-	.init = 0,
-	.filter = 0,
-	.nesting = ATOMIC_INIT(0),
-	.channel.facilities = 
-		{	ATOMIC_INIT(0),
-			ATOMIC_INIT(0),
-			ATOMIC_INIT(0),
-			ATOMIC_INIT(0)
-		},
-	.channel.cpu = 
-		{ ATOMIC_INIT(0),
-			ATOMIC_INIT(0),
-			ATOMIC_INIT(0),
-			ATOMIC_INIT(0)
-		},
-};
-#endif //0
 
-__thread struct ltt_trace_info *thread_trace_info = NULL;
+/* Writer (the traced application) */
 
+__thread struct ltt_trace_info *thread_trace_info = NULL;
 
-/* signal handling */
+void ltt_usertrace_fast_buffer_switch(void)
+{
+	kill(thread_trace_info->daemon_id, SIGUSR1);
+}
 
-static void handler(int signo)
+static void ltt_usertrace_fast_cleanup(void *arg)
 {
-	printf("Signal %d received\n", signo);
+	kill(thread_trace_info->daemon_id, SIGUSR2);
 }
 
+/* Reader (the disk dumper daemon) */
 
+static pid_t ppid = 0;
+static int parent_exited = 0;
 
-void ltt_usertrace_fast_buffer_switch(void)
+/* signal handling */
+static void handler_sigusr1(int signo)
 {
-	kill(thread_trace_info->daemon_id, SIGUSR1);
+	printf("Signal %d received : parent buffer switch.\n", signo);
+}
+
+static void handler_sigusr2(int signo)
+{
+	printf("Signal %d received : parent exited.\n", signo);
+	parent_exited = 1;
+}
+
+static void handler_sigalarm(int signo)
+{
+	printf("Signal %d received\n", signo);
+
+	if(getppid() != ppid) {
+		/* Parent died */
+		printf("Parent %lu died, cleaning up\n", ppid);
+		ppid = 0;
+	}
+	alarm(3);
 }
 
+
+/* This function is called by ltt_thread_init which has signals blocked */
 static void ltt_usertrace_fast_daemon(struct ltt_trace_info *shared_trace_info,
 		sigset_t oldset)
 {
 	struct sigaction act;
 	int ret;
 
+	ppid = getppid();
+
 	printf("ltt_usertrace_fast_daemon : init is %d, pid is %lu\n",
 			shared_trace_info->init, getpid());
 
-	act.sa_handler = handler;
+	act.sa_handler = handler_sigusr1;
 	act.sa_flags = 0;
 	sigemptyset(&(act.sa_mask));
 	sigaddset(&(act.sa_mask), SIGUSR1);
 	sigaction(SIGUSR1, &act, NULL);
+
+	act.sa_handler = handler_sigusr2;
+	act.sa_flags = 0;
+	sigemptyset(&(act.sa_mask));
+	sigaddset(&(act.sa_mask), SIGUSR2);
+	sigaction(SIGUSR2, &act, NULL);
+
+	act.sa_handler = handler_sigalarm;
+	act.sa_flags = 0;
+	sigemptyset(&(act.sa_mask));
+	sigaddset(&(act.sa_mask), SIGALRM);
+	sigaction(SIGALRM, &act, NULL);
+
 	/* Enable signals */
 	ret = pthread_sigmask(SIG_SETMASK, &oldset, NULL);
 	if(ret) {
 		printf("Error in pthread_sigmask\n");
 	}
 
+	alarm(3);
+
 	while(1) {
+		sleep(1);
 		pause();
+		if(ppid == 0) break; /* parent died */
+		if(parent_exited) break;
 		printf("Doing a buffer switch read. pid is : %lu\n", getpid());
+		//printf("Test parent. pid is : %lu, ppid is %lu\n", getpid(), getppid());
 	}
 
+	/* Buffer force switch (flush) */
+	//TODO
+	
+	/* The parent thread is dead and we have finished with the buffer */
+	munmap(shared_trace_info, sizeof(*shared_trace_info));
+	
+	exit(0);
 }
 
-void ltt_thread_init(void)
+
+/* Reader-writer initialization */
+
+static enum ltt_process_role { LTT_ROLE_WRITER, LTT_ROLE_READER }
+	role = LTT_ROLE_WRITER;
+
+
+void ltt_rw_init(void)
 {
 	pid_t pid;
 	struct ltt_trace_info *shared_trace_info;
@@ -162,6 +195,7 @@ void ltt_thread_init(void)
 		}
 	} else if(pid == 0) {
 		/* Child */
+		role = LTT_ROLE_READER;
 		ltt_usertrace_fast_daemon(shared_trace_info, oldset);
 		/* Should never return */
 		exit(-1);
@@ -171,16 +205,26 @@ void ltt_thread_init(void)
 	}
 }
 
+static __thread struct _pthread_cleanup_buffer cleanup_buffer;
+
+void ltt_thread_init(void)
+{
+	_pthread_cleanup_push(&cleanup_buffer, ltt_usertrace_fast_cleanup, NULL);
+	ltt_rw_init();
+}
+	
 void __attribute__((constructor)) __ltt_usertrace_fast_init(void)
 {
   printf("LTT usertrace-fast init\n");
 
-	ltt_thread_init();
+	ltt_rw_init();
 }
 
 void __attribute__((destructor)) __ltt_usertrace_fast_fini(void)
 {
-  printf("LTT usertrace-fast fini\n");
-
+	if(role == LTT_ROLE_WRITER) {
+	  printf("LTT usertrace-fast fini\n");
+		ltt_usertrace_fast_cleanup(NULL);
+	}
 }
 
diff --git a/usertrace-fast/test.c b/usertrace-fast/test.c
index 898b86af..ca528fbd 100644
--- a/usertrace-fast/test.c
+++ b/usertrace-fast/test.c
@@ -21,7 +21,7 @@ void *thr1(void *arg)
 	}
 
   //return ((void*)1);
-	//pthread_exit((void*)1);
+	pthread_exit((void*)1);
 }
 
 void *thr2(void *arg)
@@ -32,14 +32,14 @@ void *thr2(void *arg)
     printf("thread 2, thread id : %lu, pid %lu\n", pthread_self(), getpid());
     sleep(2);
   //}
-  //return ((void*)2);
-	//pthread_exit((void*)2);
 	for(i=0; i<2; i++) {
 		ltt_usertrace_fast_buffer_switch();
 		sleep(3);
 	}
 
 
+  return ((void*)2);	/* testing "die" */
+	//pthread_exit((void*)2);
 }