| Message ID | 20200224002033.17860-1-judge.packham@gmail.com |
|---|---|
| State | Accepted |
| Commit | 6d8eae9ab7d17ca3ce84c5e6e29bd452936ad407 |
| Headers | show |
| Series | watchdog: Handle timer wrap around | expand |
On 24.02.20 01:20, Chris Packham wrote: > On some platforms/architectures the value from get_timer() can wrap. > This is particularly problematic when long-running code needs to measure > a time difference as is the case with watchdog_reset() which tries to > avoid tickling the watchdog too frequently. > > Use time_after() from time.h instead of a plain > comparison to avoid > any issues with the time wrapping on a system that has been sitting in > u-boot for a long time. > > Signed-off-by: Chris Packham <judge.packham at gmail.com> Reviewed-by: Stefan Roese <sr at denx.de> Thanks, Stefan
On 24.02.20 01:20, Chris Packham wrote: > On some platforms/architectures the value from get_timer() can wrap. > This is particularly problematic when long-running code needs to measure > a time difference as is the case with watchdog_reset() which tries to > avoid tickling the watchdog too frequently. > > Use time_after() from time.h instead of a plain > comparison to avoid > any issues with the time wrapping on a system that has been sitting in > u-boot for a long time. > > Signed-off-by: Chris Packham <judge.packham at gmail.com> Applied to u-boot-marvell/master. Thanks, Stefan
diff --git a/drivers/watchdog/wdt-uclass.c b/drivers/watchdog/wdt-uclass.c index cf1c52747397..d9e4dc7cb8a4 100644 --- a/drivers/watchdog/wdt-uclass.c +++ b/drivers/watchdog/wdt-uclass.c @@ -7,6 +7,7 @@ #include <dm.h> #include <errno.h> #include <hang.h> +#include <time.h> #include <wdt.h> #include <dm/device-internal.h> #include <dm/lists.h> @@ -83,7 +84,7 @@ void watchdog_reset(void) /* Do not reset the watchdog too often */ now = get_timer(0); - if (now > next_reset) { + if (time_after(now, next_reset)) { next_reset = now + 1000; /* reset every 1000ms */ wdt_reset(gd->watchdog_dev); }
On some platforms/architectures the value from get_timer() can wrap. This is particularly problematic when long-running code needs to measure a time difference as is the case with watchdog_reset() which tries to avoid tickling the watchdog too frequently. Use time_after() from time.h instead of a plain > comparison to avoid any issues with the time wrapping on a system that has been sitting in u-boot for a long time. Signed-off-by: Chris Packham <judge.packham at gmail.com> --- drivers/watchdog/wdt-uclass.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)