[PATCH 18/38] drivers/media/video: Use time_before, time_before_eq,etc.

From: Julia Lawall
Date: Mon Dec 24 2007 - 09:39:45 EST


From: Julia Lawall <julia@xxxxxxx>

The functions time_before, time_before_eq, time_after, and time_after_eq
are more robust for comparing jiffies against other values.

A simplified version of the semantic patch making this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@ change_compare_np @
expression E;
@@

(
- jiffies <= E
+ time_before_eq(jiffies,E)
|
- jiffies >= E
+ time_after_eq(jiffies,E)
|
- jiffies < E
+ time_before(jiffies,E)
|
- jiffies > E
+ time_after(jiffies,E)
)

@ include depends on change_compare_np @
@@

#include <linux/jiffies.h>

@ no_include depends on !include && change_compare_np @
@@

#include <linux/...>
+ #include <linux/jiffies.h>
// </smpl>

Signed-off-by: Julia Lawall <julia@xxxxxxx>
---

diff -r -u -p a/drivers/media/video/c-qcam.c b/drivers/media/video/c-qcam.c
--- a/drivers/media/video/c-qcam.c 2007-11-01 10:30:39.000000000 +0100
+++ b/drivers/media/video/c-qcam.c 2007-12-23 20:36:52.000000000 +0100
@@ -36,6 +36,7 @@
#include <linux/videodev.h>
#include <media/v4l2-common.h>
#include <linux/mutex.h>
+#include <linux/jiffies.h>

#include <asm/uaccess.h>

@@ -95,7 +96,8 @@ static unsigned int qcam_await_ready1(st
unsigned long oldjiffies = jiffies;
unsigned int i;

- for (oldjiffies = jiffies; (jiffies - oldjiffies) < msecs_to_jiffies(40); )
+ for (oldjiffies = jiffies;
+ time_before(jiffies, oldjiffies + msecs_to_jiffies(40)); )
if (qcam_ready1(qcam) == value)
return 0;

@@ -120,7 +122,8 @@ static unsigned int qcam_await_ready2(st
unsigned long oldjiffies = jiffies;
unsigned int i;

- for (oldjiffies = jiffies; (jiffies - oldjiffies) < msecs_to_jiffies(40); )
+ for (oldjiffies = jiffies;
+ time_before(jiffies, oldjiffies + msecs_to_jiffies(40)); )
if (qcam_ready2(qcam) == value)
return 0;

diff -r -u -p a/drivers/media/video/ivtv/ivtv-fileops.c b/drivers/media/video/ivtv/ivtv-fileops.c
--- a/drivers/media/video/ivtv/ivtv-fileops.c 2007-11-01 10:30:39.000000000 +0100
+++ b/drivers/media/video/ivtv/ivtv-fileops.c 2007-12-23 20:37:15.000000000 +0100
@@ -219,7 +219,9 @@ static struct ivtv_buffer *ivtv_get_buff
/* Process pending program info updates and pending VBI data */
ivtv_update_pgm_info(itv);

- if (jiffies - itv->dualwatch_jiffies > msecs_to_jiffies(1000)) {
+ if (time_after(jiffies,
+ itv->dualwatch_jiffies +
+ msecs_to_jiffies(1000))) {
itv->dualwatch_jiffies = jiffies;
ivtv_dualwatch(itv);
}
diff -r -u -p a/drivers/media/video/ivtv/ivtv-mailbox.c b/drivers/media/video/ivtv/ivtv-mailbox.c
--- a/drivers/media/video/ivtv/ivtv-mailbox.c 2007-10-22 11:25:10.000000000 +0200
+++ b/drivers/media/video/ivtv/ivtv-mailbox.c 2007-12-23 20:37:40.000000000 +0100
@@ -177,7 +177,8 @@ static int get_mailbox(struct ivtv *itv,

/* Sleep before a retry, if not atomic */
if (!(flags & API_NO_WAIT_MB)) {
- if (jiffies - then > msecs_to_jiffies(10*retries))
+ if (time_after(jiffies,
+ then + msecs_to_jiffies(10*retries)))
break;
ivtv_msleep_timeout(10, 0);
}
@@ -244,7 +245,9 @@ static int ivtv_api_call(struct ivtv *it
data, then just return 0 as there is no need to issue this command again.
Just an optimization to prevent unnecessary use of mailboxes. */
if (itv->api_cache[cmd].last_jiffies &&
- jiffies - itv->api_cache[cmd].last_jiffies < msecs_to_jiffies(1800000) &&
+ time_before(jiffies,
+ itv->api_cache[cmd].last_jiffies +
+ msecs_to_jiffies(1800000)) &&
!memcmp(data, itv->api_cache[cmd].data, sizeof(itv->api_cache[cmd].data))) {
itv->api_cache[cmd].last_jiffies = jiffies;
return 0;
@@ -299,7 +302,7 @@ static int ivtv_api_call(struct ivtv *it
}
}
while (!(readl(&mbox->flags) & IVTV_MBOX_FIRMWARE_DONE)) {
- if (jiffies - then > api_timeout) {
+ if (time_after(jiffies, then + api_timeout)) {
IVTV_DEBUG_WARN("Could not get result (%s)\n", api_info[cmd].name);
/* reset the mailbox, but it is likely too late already */
write_sync(0, &mbox->flags);
@@ -311,7 +314,7 @@ static int ivtv_api_call(struct ivtv *it
else
ivtv_msleep_timeout(1, 0);
}
- if (jiffies - then > msecs_to_jiffies(100))
+ if (time_after(jiffies, then + msecs_to_jiffies(100)))
IVTV_DEBUG_WARN("%s took %u jiffies\n",
api_info[cmd].name,
jiffies_to_msecs(jiffies - then));
diff -r -u -p a/drivers/media/video/ivtv/ivtv-streams.c b/drivers/media/video/ivtv/ivtv-streams.c
--- a/drivers/media/video/ivtv/ivtv-streams.c 2007-12-13 20:41:15.000000000 +0100
+++ b/drivers/media/video/ivtv/ivtv-streams.c 2007-12-23 20:37:55.000000000 +0100
@@ -783,7 +783,8 @@ int ivtv_stop_v4l2_encode_stream(struct

/* wait 2s for EOS interrupt */
while (!test_bit(IVTV_F_I_EOS, &itv->i_flags) &&
- jiffies < then + msecs_to_jiffies (2000)) {
+ time_before(jiffies,
+ then + msecs_to_jiffies(2000))) {
schedule_timeout(msecs_to_jiffies(10));
}

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