Add ddi_time_after and friends

When comparing times gotten from ddi_get_lbolt, we have to take account of
wrap around of jiffies. Therefore, we cannot use 't1 < t2'. Instead we should
use 't1 - t2 < 0'.

This patch add ddi_time_after and friends to address this issue. They have
strict type restriction, clock_t for vanilla and int64_t for 64 version, to
prevent type conversion from screwing things.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #335
This commit is contained in:
Chunwei Chen
2014-02-25 17:16:55 +08:00
committed by Brian Behlendorf
parent 6c48cd8ac2
commit 545e9ac00a
2 changed files with 19 additions and 5 deletions
+14
View File
@@ -35,6 +35,20 @@
#define ddi_get_lbolt() ((clock_t)jiffies)
#define ddi_get_lbolt64() ((int64_t)get_jiffies_64())
#define ddi_time_before(a, b) (typecheck(clock_t, a) && \
typecheck(clock_t, b) && \
((a) - (b) < 0))
#define ddi_time_after(a, b) ddi_time_before(b, a)
#define ddi_time_before_eq(a, b) (!ddi_time_after(a, b))
#define ddi_time_after_eq(a, b) ddi_time_before_eq(b, a)
#define ddi_time_before64(a, b) (typecheck(int64_t, a) && \
typecheck(int64_t, b) && \
((a) - (b) < 0))
#define ddi_time_after64(a, b) ddi_time_before64(b, a)
#define ddi_time_before_eq64(a, b) (!ddi_time_after64(a, b))
#define ddi_time_after_eq64(a, b) ddi_time_before_eq64(b, a)
#define delay(ticks) schedule_timeout_uninterruptible(ticks)
#define SEC_TO_TICK(sec) ((sec) * HZ)