Revert "FROMLIST: Fix an integer overflow issue in the NSEC_PER_SEC constant"

This reverts commit 062cbc4876.

There was no follow up of this patch upstream, also the cherry-pick is
not clean. Revert this as it creates merge conflicts with upstream
changes and if really needed, please send a new version upstream.

Bug: 444295917
Cc: Wake Liu <wakel@google.com>
Change-Id: I8ffdf3e8331c9318749fdadf9759921b209e424b
Signed-off-by: Carlos Llamas <cmllamas@google.com>

BUILD.bazel

@@ -2424,7 +2424,6 @@ cc_library(
     name = "kselftest_timers_common_hdrs",
     hdrs = [
         "include/vdso/time64.h",
-        "tools/testing/selftests/timers/helpers.h",
     ],
     copts = _KSELFTEST_COPTS,
     includes = ["."],

tools/testing/selftests/timers/alarmtimer-suspend.c

@@ -31,9 +31,8 @@
 #include <include/vdso/time64.h>
 #include <errno.h>
 #include "../kselftest.h"
-#include "helpers.h"
 
-#define UNREASONABLE_LAT (NSEC_PER_SEC * 5LL) /* hopefully we resume in 5 secs */
+#define UNREASONABLE_LAT (NSEC_PER_SEC * 5) /* hopefully we resume in 5 secs */
 
 #define SUSPEND_SECS 15
 int alarmcount;
@@ -71,6 +70,14 @@ char *clockstring(int clockid)
 }
 
 
+long long timespec_sub(struct timespec a, struct timespec b)
+{
+	long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;
+
+	ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
+	return ret;
+}
+
 int final_ret;
 
 void sigalarm(int signo)
@@ -81,8 +88,8 @@ void sigalarm(int signo)
 	clock_gettime(alarm_clock_id, &ts);
 	alarmcount++;
 
-	delta_ns = timespec_sub(ts, start_time);
-	delta_ns -= (long long)NSEC_PER_SEC * SUSPEND_SECS * alarmcount;
+	delta_ns = timespec_sub(start_time, ts);
+	delta_ns -= NSEC_PER_SEC * SUSPEND_SECS * alarmcount;
 
 	printf("ALARM(%i): %ld:%ld latency: %lld ns ", alarmcount, ts.tv_sec,
 							ts.tv_nsec, delta_ns);

tools/testing/selftests/timers/helpers.h

@@ -1,32 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef SELFTESTS_TIMERS_HELPERS_H
-#define SELFTESTS_TIMERS_HELPERS_H
-
-#include <time.h>
-
-#ifndef NSEC_PER_SEC
-#define NSEC_PER_SEC 1000000000L
-#endif
-
-/*
- * timespec_to_ns - Convert timespec to nanoseconds
- */
-static inline long long timespec_to_ns(const struct timespec *ts)
-{
-	return ((long long) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
-}
-
-/*
- * timespec_sub - Subtract two timespec values
- *
- * @a: first timespec
- * @b: second timespec
- *
- * Returns a - b in nanoseconds.
- */
-static inline long long timespec_sub(struct timespec a, struct timespec b)
-{
-	return timespec_to_ns(&a) - timespec_to_ns(&b);
-}
-
-#endif /* SELFTESTS_TIMERS_HELPERS_H */

tools/testing/selftests/timers/nanosleep.c

@@ -188,7 +188,7 @@ int main(int argc, char **argv)
 		fflush(stdout);
 
 		length = 10;
-		while (length <= (NSEC_PER_SEC * 10LL)) {
+		while (length <= (NSEC_PER_SEC * 10)) {
 			ret = nanosleep_test(clockid, length);
 			if (ret == UNSUPPORTED) {
 				ksft_test_result_skip("%-31s\n", clockstring(clockid));

tools/testing/selftests/timers/nsleep-lat.c

@@ -26,7 +26,6 @@
 #include <signal.h>
 #include <include/vdso/time64.h>
 #include "../kselftest.h"
-#include "helpers.h"
 
 #define UNRESONABLE_LATENCY 40000000 /* 40ms in nanosecs */
 
@@ -75,6 +74,14 @@ struct timespec timespec_add(struct timespec ts, unsigned long long ns)
 }
 
 
+long long timespec_sub(struct timespec a, struct timespec b)
+{
+	long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;
+
+	ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
+	return ret;
+}
+
 int nanosleep_lat_test(int clockid, long long ns)
 {
 	struct timespec start, end, target;
@@ -139,7 +146,7 @@ int main(int argc, char **argv)
 			continue;
 
 		length = 10;
-		while (length <= (NSEC_PER_SEC * 10LL)) {
+		while (length <= (NSEC_PER_SEC * 10)) {
 			ret = nanosleep_lat_test(clockid, length);
 			if (ret)
 				break;

tools/testing/selftests/timers/valid-adjtimex.c

@@ -264,16 +264,16 @@ int validate_set_offset(void)
 	if (set_offset(-NSEC_PER_SEC - 1, 1))
 		return -1;
 
-	if (set_offset(5LL * NSEC_PER_SEC, 1))
+	if (set_offset(5 * NSEC_PER_SEC, 1))
 		return -1;
 
-	if (set_offset(-5LL * NSEC_PER_SEC, 1))
+	if (set_offset(-5 * NSEC_PER_SEC, 1))
 		return -1;
 
-	if (set_offset(5LL * NSEC_PER_SEC + NSEC_PER_SEC / 2, 1))
+	if (set_offset(5 * NSEC_PER_SEC + NSEC_PER_SEC / 2, 1))
 		return -1;
 
-	if (set_offset(-5LL * NSEC_PER_SEC - NSEC_PER_SEC / 2, 1))
+	if (set_offset(-5 * NSEC_PER_SEC - NSEC_PER_SEC / 2, 1))
 		return -1;
 
 	if (set_offset(USEC_PER_SEC - 1, 0))