[PATCH] child process synchronization NIC startup parameters

[Kaisen You]

In meson_test, because the child process does not synchronize
the NIC startup parameters of the parent process at startup,
it uses all NICs bound by vfio as startup parameters by default,
and an exception occurs in the subsequent hugefile check,
causing the test to fail. Synchronize the NIC startup parameters
of the parent process to the child process to solve this problem.

Fixes: 786b29255c49 ("test: fix file prefix discovery")
Cc: stable at dpdk.org

Signed-off-by: Kaisen You <kaisenx.you at intel.com>
---
 app/test/process.h | 81 ++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 78 insertions(+), 3 deletions(-)

diff --git a/app/test/process.h b/app/test/process.h
index 1f073b9c5c..95dffab69c 100644
--- a/app/test/process.h
+++ b/app/test/process.h
@@ -15,6 +15,8 @@
 #include <string.h> /* strerror */
 #include <unistd.h> /* readlink */
 #include <dirent.h>
+#include <fcntl.h>
+#include <ctype.h>
 
 #include <rte_string_fns.h> /* strlcpy */
 
@@ -24,6 +26,7 @@
 #else
 #define self "self"
 #define exe "exe"
+#define MAX_EXTRA_ARGS 32
 #endif
 
 #ifdef RTE_LIB_PDUMP
@@ -34,6 +37,50 @@ extern uint16_t flag_for_send_pkts;
 #endif
 #endif
 
+/* get cmdline form PID. Read process info form /proc/$PID. */
+static char *get_cmdline_from_pid(pid_t pid, char *buf, int len)
+{
+	char filename[PATH_MAX];
+	char *name = NULL;
+	int fd;
+	int ret;
+
+	if (pid < 1 || buf == NULL || len < 0) {
+		printf("%s: illegal param\n", __func__);
+		return NULL;
+	}
+
+	snprintf(filename, PATH_MAX, "/proc/%d/cmdline", pid);
+	memset(buf, 0, len);
+	fd = open(filename, O_RDONLY);
+	if (fd < 0) {
+		perror("open:");
+		return NULL;
+	}
+	ret = read(fd, buf, len);
+	close(fd);
+
+	if (ret < 0)
+		return NULL;
+
+	if (buf[ret-1] == '\n')
+		buf[--ret] = 0;
+
+	name = buf;
+	while (ret) {
+		if (((unsigned char)*name) < ' ')
+			*name = ' ';
+		name++;
+		ret--;
+	}
+	*name = 0;
+
+	if (buf[0])
+		return buf;
+
+	return NULL;
+}
+
 /*
  * launches a second copy of the test process using the given argv parameters,
  * which should include argv[0] as the process name. To identify in the
@@ -44,9 +91,15 @@ static inline int
 process_dup(const char *const argv[], int numargs, const char *env_value)
 {
 	int num;
-	char *argv_cpy[numargs + 1];
-	int i, status;
+	char *argv_cpy[MAX_EXTRA_ARGS];
+	int i, status, n, s, j;
 	char path[32];
+	char buf[1024];
+	char *token;
+	char str_1[] = "-a";
+	char str_2[] = " ";
+	char *argv_str[MAX_EXTRA_ARGS];
+	char *argv_copy[MAX_EXTRA_ARGS];
 #ifdef RTE_LIB_PDUMP
 #ifdef RTE_NET_RING
 	pthread_t thread;
@@ -113,10 +166,32 @@ process_dup(const char *const argv[], int numargs, const char *env_value)
 			closedir(dir);
 		}
 #endif
+		/* Add the -a parameter to the child process start parameter */
+		get_cmdline_from_pid(getppid(), buf, 1024);
+		token = strtok(buf, str_2);
+		argv_str[0] = strdup(token);
+		n = 0;
+		j = 0;
+		while (token != NULL) {
+			n = n + 1;
+			argv_str[n] = strdup(token);
+			token = strtok(NULL, str_2);
+		}
+		for (s = 0; s < n; s++) {
+			if (strcmp(argv_str[s], str_1) == 0 ||
+				strcmp(argv_str[s + 1], str_1) == 0) {
+				argv_copy[j] = strdup(argv_str[s + 1]);
+				j++;
+			}
+		}
+		for (s = 0; s < j; s++)
+			argv_cpy[numargs + s] = strdup(argv_copy[s]);
+
 		printf("Running binary with argv[]:");
-		for (i = 0; i < num; i++)
+		for (i = 0; i < num + j; i++)
 			printf("'%s' ", argv_cpy[i]);
 		printf("\n");
+		argv_cpy[numargs + j] = NULL;
 		fflush(stdout);
 
 		/* set the environment variable */
-- 
2.25.1