sem_post/8-1: improve "child blocked on semaphore" detection
With POSIX semaphore we can't tell how many processes are waiting
on semaphore. Each child process in this test uses 2 semaphores,
first can always be taken and is used only for its semval (as counter),
to tell if child started and presumably will soon block on the second
semaphore.
Test assumes that if child holds first semaphore, then it will
take second one within 100us.
This patch replaces that sleep with a wait until child process
state changes to 'S' (sleeping).
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Cyril Hrubis <chrubis@suse.cz>
diff --git a/testcases/open_posix_testsuite/conformance/interfaces/sem_post/8-1.c b/testcases/open_posix_testsuite/conformance/interfaces/sem_post/8-1.c
index 08e9463..d41a7e4 100644
--- a/testcases/open_posix_testsuite/conformance/interfaces/sem_post/8-1.c
+++ b/testcases/open_posix_testsuite/conformance/interfaces/sem_post/8-1.c
@@ -44,6 +44,7 @@
#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
+#include "proc.h"
#define TEST "sem_post_8-1"
@@ -184,7 +185,8 @@
usleep(100);
sem_getvalue(sem_1, &val);
} while (val != 1);
- usleep(100);
+ tst_process_state_wait3(c_1, 'S', 2000);
+ tst_process_state_wait3(c_2, 'S', 2000);
c_3 = fork();
switch (c_3) {
@@ -204,7 +206,7 @@
usleep(100);
sem_getvalue(sem_1, &val);
} while (val != 0);
- usleep(100);
+ tst_process_state_wait3(c_3, 'S', 2000);
/* Ok, let's release the lock */
fprintf(stderr, "P: release lock\n");
diff --git a/testcases/open_posix_testsuite/include/proc.h b/testcases/open_posix_testsuite/include/proc.h
new file mode 100644
index 0000000..8272d9d
--- /dev/null
+++ b/testcases/open_posix_testsuite/include/proc.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2017 Linux Test Project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms in version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ */
+
+#ifdef __linux__
+# include <errno.h>
+# include <string.h>
+int tst_process_state_wait3(pid_t pid, const char state,
+ unsigned long maxwait_ms)
+{
+ char proc_path[128], cur_state;
+ int wait_step_ms = 10;
+ unsigned long waited_ms = 0;
+
+ snprintf(proc_path, sizeof(proc_path), "/proc/%i/stat", pid);
+
+ for (;;) {
+ FILE *f = fopen(proc_path, "r");
+
+ if (!f) {
+ fprintf(stderr, "Failed to open '%s': %s\n",
+ proc_path, strerror(errno));
+ return 1;
+ }
+
+ if (fscanf(f, "%*i %*s %c", &cur_state) != 1) {
+ fclose(f);
+ fprintf(stderr, "Failed to read '%s': %s\n",
+ proc_path, strerror(errno));
+ return 1;
+ }
+ fclose(f);
+
+ if (state == cur_state)
+ return 0;
+
+ usleep(wait_step_ms * 1000);
+ waited_ms += wait_step_ms;
+
+ if (waited_ms >= maxwait_ms) {
+ fprintf(stderr, "Reached max wait time\n");
+ return 1;
+ }
+ }
+}
+#else
+int tst_process_state_wait3(pid_t pid, const char state,
+ unsigned long maxwait_ms)
+{
+ usleep(maxwait_ms * 1000);
+ return 0;
+}
+#endif