* defs.h: Add new struct tcb fields: wait_status, next_need_service.

make flags field wider (ints are easier to work with on many CPUs).
* strace.c (trace): Split this function into two:
collect_stopped_tcbs() and handle_stopped_tcbs().
Now we collect *all* waitable tasks, then handle them all,
then repeat.
Fixes RH#478419 "Some threads stop when strace with -f option
is executed on a multi-thread process"
* test/many_looping_threads.c: example program which cna't be straced
successfully without this fix.

1 files changed, 37 insertions, 0 deletions

diff --git a/test/many_looping_threads.c b/test/many_looping_threads.c
new file mode 100644
index 0000000..d8f7f8d
--- /dev/null
+++ b/test/many_looping_threads.c
@@ -0,0 +1,37 @@
+/* This test is not yet added to Makefile */
+
+#include <stdio.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <stdlib.h>
+
+static int thd_no;
+
+static void *sub_thd(void *c)
+{
+	fprintf(stderr, "sub-thread %d created\n", ++thd_no);
+	for (;;)
+		getuid();
+	return NULL;
+}
+
+int main(int argc, char **argv)
+{
+	int i;
+	pthread_t *thd;
+	int num_threads = 1;
+
+	if (argv[1])
+		num_threads = atoi(argv[1]);
+
+	thd = malloc(num_threads * sizeof(thd[0]));
+	fprintf(stderr, "test start, num_threads:%d...\n", num_threads);
+	for (i = 0; i < num_threads; i++) {
+		pthread_create(&thd[i], NULL, sub_thd, NULL);
+		fprintf(stderr, "after pthread_create\n");
+	}
+	/* Exit. This kills all threads */
+	return 0;
+}