From: Wang Qing <wangqing@xxxxxxxx> It is better to use time_xxx() directly instead of jiffies judgment for understanding. Signed-off-by: Wang Qing <wangqing@xxxxxxxx> --- drivers/block/xen-blkback/blkback.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index d1e2646..aecc1f4 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -42,6 +42,7 @@ #include <linux/delay.h> #include <linux/freezer.h> #include <linux/bitmap.h> +#include <linux/jiffies.h> #include <xen/events.h> #include <xen/page.h> @@ -134,8 +135,8 @@ module_param(log_stats, int, 0644); static inline bool persistent_gnt_timeout(struct persistent_gnt *persistent_gnt) { - return pgrant_timeout && (jiffies - persistent_gnt->last_used >= - HZ * pgrant_timeout); + return pgrant_timeout && time_is_before_eq_jiffies( + persistent_gnt->last_used + HZ * pgrant_timeout); } #define vaddr(page) ((unsigned long)pfn_to_kaddr(page_to_pfn(page))) -- 2.7.4