Merge branch 'master' into pr6866

1 files changed, 129 insertions, 5 deletions

diff --git a/runtime/staprun/relay.c b/runtime/staprun/relay.c
index 19621933..50f295b5 100644
--- a/runtime/staprun/relay.c
+++ b/runtime/staprun/relay.c
@@ -17,6 +17,9 @@ static pthread_t reader[NR_CPUS];
 static int relay_fd[NR_CPUS];
 static int bulkmode = 0;
 static volatile int stop_threads = 0;
+static time_t *time_backlog[NR_CPUS];
+static int backlog_order=0;
+#define BACKLOG_MASK ((1 << backlog_order) - 1)
 
 /*
  * ppoll exists in glibc >= 2.4
@@ -44,6 +47,90 @@ static int ppoll(struct pollfd *fds, nfds_t nfds,
 }
 #endif
 
+int init_backlog(int cpu)
+{
+	int order = 0;
+	if (!fnum_max)
+		return 0;
+	while (fnum_max >> order) order++;
+	if (fnum_max == 1<<(order-1)) order--;
+	time_backlog[cpu] = (time_t *)calloc(1<<order, sizeof(time_t));
+	if (time_backlog[cpu] == NULL) {
+		_err("Memory allocation failed\n");
+		return -1;
+	}
+	backlog_order = order;
+	return 0;
+}
+
+void write_backlog(int cpu, int fnum, time_t t)
+{
+	time_backlog[cpu][fnum & BACKLOG_MASK] = t;
+}
+
+time_t read_backlog(int cpu, int fnum)
+{
+	return time_backlog[cpu][fnum & BACKLOG_MASK];
+}
+
+int make_outfile_name(char *buf, int max, int fnum, int cpu, time_t t)
+{
+	int len;
+	len = stap_strfloctime(buf, max, outfile_name, t);
+	if (len < 0) {
+		err("Invalid FILE name format\n");
+  		return -1;
+  	}
+	if (bulkmode) {
+		/* special case: for testing we sometimes want to write to /dev/null */
+		if (strcmp(outfile_name, "/dev/null") == 0) {
+			strcpy(buf, "/dev/null");
+		} else {
+			if (snprintf_chk(&buf[len], PATH_MAX - len,
+					 "_cpu%d.%d", cpu, fnum))
+				return -1;
+		}
+	} else {
+		/* stream mode */
+		if (snprintf_chk(&buf[len], PATH_MAX - len, ".%d", fnum))
+			return -1;
+	}
+	return 0;
+}
+
+static int open_outfile(int fnum, int cpu, int remove_file)
+{
+	char buf[PATH_MAX];
+	time_t t;
+	if (!outfile_name) {
+		_err("-S is set without -o. Please file a bug report.\n");
+		return -1;
+	}
+
+	time(&t);
+	if (fnum_max) {
+		if (remove_file) {
+			 /* remove oldest file */
+			if (make_outfile_name(buf, PATH_MAX, fnum - fnum_max,
+				 cpu, read_backlog(cpu, fnum - fnum_max)) < 0)
+				return -1;
+			remove(buf); /* don't care */
+		}
+		write_backlog(cpu, fnum, t);
+	}
+
+	if (make_outfile_name(buf, PATH_MAX, fnum, cpu, t) < 0)
+		return -1;
+	out_fd[cpu] = open (buf, O_CREAT|O_TRUNC|O_WRONLY, 0666);
+	if (out_fd[cpu] < 0) {
+		perr("Couldn't open output file %s", buf);
+		return -1;
+	}
+	if (set_clexec(out_fd[cpu]) < 0)
+		return -1;
+	return 0;
+}
+
 /**
  *	reader_thread - per-cpu channel buffer reader
  */
@@ -57,6 +144,9 @@ static void *reader_thread(void *data)
 	struct timespec tim = {.tv_sec=0, .tv_nsec=200000000}, *timeout = &tim;
 	sigset_t sigs;
 	struct sigaction sa;
+	off_t wsize = 0;
+	int fnum = 0;
+	int remove_file = 0;
 
 	sigemptyset(&sigs);
 	sigaddset(&sigs,SIGUSR2);
@@ -99,6 +189,19 @@ static void *reader_thread(void *data)
                         }
                 }
 		while ((rc = read(relay_fd[cpu], buf, sizeof(buf))) > 0) {
+			wsize += rc;
+			/* Switching file */
+			if (fsize_max && wsize > fsize_max) {
+				close(out_fd[cpu]);
+				fnum++;
+				if (fnum_max && fnum == fnum_max)
+					remove_file = 1;
+				if (open_outfile(fnum, cpu, remove_file) < 0) {
+					perr("Couldn't open file for cpu %d, exiting.", cpu);
+					return(NULL);
+				}
+				wsize = 0;
+			}
 			if (write(out_fd[cpu], buf, rc) != rc) {
 				perr("Couldn't write to output %d for cpu %d, exiting.", out_fd[cpu], cpu);
 				return(NULL);
@@ -116,7 +219,7 @@ static void *reader_thread(void *data)
  */
 int init_relayfs(void)
 {
-	int i;
+	int i, len;
 	struct statfs st;
 	char rqbuf[128];
 	char buf[PATH_MAX], relay_filebase[PATH_MAX];
@@ -163,14 +266,29 @@ int init_relayfs(void)
 		return -1;
 	}
 
-	if (bulkmode) {
+	if (fsize_max) {
+		/* switch file mode */
+		for (i = 0; i < ncpus; i++) {
+			if (init_backlog(i) < 0)
+				return -1;
+  			if (open_outfile(0, i, 0) < 0)
+  				return -1;
+		}
+	} else if (bulkmode) {
 		for (i = 0; i < ncpus; i++) {
 			if (outfile_name) {
 				/* special case: for testing we sometimes want to write to /dev/null */
 				if (strcmp(outfile_name, "/dev/null") == 0) {
 					strcpy(buf, "/dev/null");
 				} else {
-					if (sprintf_chk(buf, "%s_%d", outfile_name, i))
+					len = stap_strfloctime(buf, PATH_MAX,
+						 outfile_name, time(NULL));
+					if (len < 0) {
+						err("Invalid FILE name format\n");
+						return -1;
+					}
+					if (snprintf_chk(&buf[len],
+						PATH_MAX - len, "_%d", i))
 						return -1;
 				}
 			} else {
@@ -189,9 +307,15 @@ int init_relayfs(void)
 	} else {
 		/* stream mode */
 		if (outfile_name) {
-			out_fd[0] = open (outfile_name, O_CREAT|O_TRUNC|O_WRONLY, 0666);
+			len = stap_strfloctime(buf, PATH_MAX,
+						 outfile_name, time(NULL));
+			if (len < 0) {
+				err("Invalid FILE name format\n");
+				return -1;
+			}
+			out_fd[0] = open (buf, O_CREAT|O_TRUNC|O_WRONLY, 0666);
 			if (out_fd[0] < 0) {
-				perr("Couldn't open output file %s", outfile_name);
+				perr("Couldn't open output file %s", buf);
 				return -1;
 			}
 			if (set_clexec(out_fd[i]) < 0)