[PATCH v3] mtd: test: Replace timeval with ktime_t in speedtest.c and torturetest.c

[Chunyan Zhang]

This patch changes the 32-bit time type (timeval) to the 64-bit one
(ktime_t), since 32-bit time types will break in the year 2038.

I use ktime_t instead of timeval to define 'start' and 'finish'
which are used to get the time for tow points.

This patch also changes do_gettimeofday() to ktime_get() accordingly,
since ktime_get returns a ktime_t, but do_gettimeofday returns a
struct timeval, and the other reason is that ktime_get() uses
the monotonic clock.

This patch is based on another patch which privides a millisecond
time difference function 'ktime_ms_delta' in ktime.h

http://lkml.iu.edu//hypermail/linux/kernel/1412.2/00625.html

Signed-off-by: Chunyan Zhang <zhang.chunyan at linaro.org>
Reviewed-by: Arnd Bergmann <arnd at arndb.de>
---
Changes since v2:
 - Use the new function ktime_ms_delta which is added in another
   patch listed up.

Changes since v1:
 - Add including <linux/ktime.h> in torturetest.c
---
 drivers/mtd/tests/speedtest.c   |   10 +++++-----
 drivers/mtd/tests/torturetest.c |   10 +++++-----
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/mtd/tests/speedtest.c b/drivers/mtd/tests/speedtest.c
index 5ee9f70..87a6e25 100644
--- a/drivers/mtd/tests/speedtest.c
+++ b/drivers/mtd/tests/speedtest.c
@@ -22,6 +22,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/init.h>
+#include <linux/ktime.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/err.h>
@@ -49,7 +50,7 @@ static int pgsize;
 static int ebcnt;
 static int pgcnt;
 static int goodebcnt;
-static struct timeval start, finish;
+static ktime_t start, finish;
 
 static int multiblock_erase(int ebnum, int blocks)
 {
@@ -168,12 +169,12 @@ static int read_eraseblock_by_2pages(int ebnum)
 
 static inline void start_timing(void)
 {
-	do_gettimeofday(&start);
+	start = ktime_get();
 }
 
 static inline void stop_timing(void)
 {
-	do_gettimeofday(&finish);
+	finish = ktime_get();
 }
 
 static long calc_speed(void)
@@ -181,8 +182,7 @@ static long calc_speed(void)
 	uint64_t k;
 	long ms;
 
-	ms = (finish.tv_sec - start.tv_sec) * 1000 +
-	     (finish.tv_usec - start.tv_usec) / 1000;
+	ms = ktime_ms_delta(finish, start);
 	if (ms == 0)
 		return 0;
 	k = goodebcnt * (mtd->erasesize / 1024) * 1000;
diff --git a/drivers/mtd/tests/torturetest.c b/drivers/mtd/tests/torturetest.c
index eeab969..7e77ed4 100644
--- a/drivers/mtd/tests/torturetest.c
+++ b/drivers/mtd/tests/torturetest.c
@@ -26,6 +26,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/init.h>
+#include <linux/ktime.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/err.h>
@@ -79,18 +80,18 @@ static unsigned char *check_buf;
 static unsigned int erase_cycles;
 
 static int pgsize;
-static struct timeval start, finish;
+static ktime_t start, finish;
 
 static void report_corrupt(unsigned char *read, unsigned char *written);
 
 static inline void start_timing(void)
 {
-	do_gettimeofday(&start);
+	start = ktime_get();
 }
 
 static inline void stop_timing(void)
 {
-	do_gettimeofday(&finish);
+	finish = ktime_get();
 }
 
 /*
@@ -322,8 +323,7 @@ static int __init tort_init(void)
 			long ms;
 
 			stop_timing();
-			ms = (finish.tv_sec - start.tv_sec) * 1000 +
-			     (finish.tv_usec - start.tv_usec) / 1000;
+			ms = ktime_ms_delta(finish, start);
 			pr_info("%08u erase cycles done, took %lu "
 			       "milliseconds (%lu seconds)\n",
 			       erase_cycles, ms, ms / 1000);
-- 
1.7.9.5