From 7a4ed937aa44acdeb8c6ba671509dc7b54b09d3a Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@tv-sign.ru>
Date: Wed, 26 Oct 2005 20:26:53 +0400
Subject: [PATCH] [PATCH] Fix cpu timers expiration time
There's a silly off-by-one error in the code that updates the expiration
of posix CPU timers, causing them to not be properly updated when they
hit exactly on their expiration time (which should be the normal case).
This causes them to then fire immediately again, and only _then_ get
properly updated.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
kernel/posix-cpu-timers.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 2f86424fa515..383ba22f0b62 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -91,7 +91,7 @@ static inline union cpu_time_count cpu_time_sub(clockid_t which_clock,
* Update expiry time from increment, and increase overrun count,
* given the current clock sample.
*/
-static inline void bump_cpu_timer(struct k_itimer *timer,
+static void bump_cpu_timer(struct k_itimer *timer,
union cpu_time_count now)
{
int i;
@@ -110,7 +110,7 @@ static inline void bump_cpu_timer(struct k_itimer *timer,
for (i = 0; incr < delta - incr; i++)
incr = incr << 1;
for (; i >= 0; incr >>= 1, i--) {
- if (delta <= incr)
+ if (delta < incr)
continue;
timer->it.cpu.expires.sched += incr;
timer->it_overrun += 1 << i;
@@ -128,7 +128,7 @@ static inline void bump_cpu_timer(struct k_itimer *timer,
for (i = 0; cputime_lt(incr, cputime_sub(delta, incr)); i++)
incr = cputime_add(incr, incr);
for (; i >= 0; incr = cputime_halve(incr), i--) {
- if (cputime_le(delta, incr))
+ if (cputime_lt(delta, incr))
continue;
timer->it.cpu.expires.cpu =
cputime_add(timer->it.cpu.expires.cpu, incr);
--
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