prctl: Add support for PR_SET_THP_DISABLE and PR_GET_THP_DISABLE

Change-Id: I04c5568a9eb78bcac632b734f34bba49cf602c4d
Refs: #1181

test/issues/1181/set_thp_and_exec.c

@@ -0,0 +1,56 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/prctl.h>
+
+#define EXARG_MAX 64
+#define CMD_MAX_LEN 1024
+
+int main(int argc, char *argv[])
+{
+	int rc = 0, i;
+	int thp_disable = 0;
+	char *exargv[EXARG_MAX] = {};
+	char *exenvp[1] = {NULL};
+	char execcmd[CMD_MAX_LEN] = {};
+
+	if (argc < 3) {
+		printf("err: too few arguments\n");
+		return -1;
+	}
+
+	if (argc > EXARG_MAX + 1) {
+		printf("err: too many arguments\n");
+		return -1;
+	}
+
+	thp_disable = atoi(argv[1]);
+
+	rc = prctl(PR_SET_THP_DISABLE, thp_disable, 0, 0, 0);
+	if (rc < 0) {
+		perror("err: PR_SET_THP_DISABLE");
+	}
+	printf("set thp_disable: %d\n", thp_disable);
+
+	for (i = 1; i < argc; i++) {
+		exargv[i - 2] = argv[i];
+	}
+
+	for (i = 0; i < EXARG_MAX; i++) {
+		if (!exargv[i]) {
+			break;
+		}
+		if (i != 0) {
+			strncat(execcmd, " ", CMD_MAX_LEN - 2);
+		}
+		strncat(execcmd, exargv[i], CMD_MAX_LEN - strlen(execcmd) - 1);
+	}
+
+	printf("exec: %s\n", execcmd);
+	execve(exargv[0], exargv, exenvp);
+
+	/* can't reach here */
+	printf("err: execve failed\n");
+	return -1;
+}