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Date: Fri, 15 Apr 2005 09:58:01 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Jesper Juhl <juhl-lkml@dif.dk>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>, Robert Love <rml@tech9.net>,
       Linus Torvalds <torvalds@osdl.org>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH] sched: fix never executed code due to expression always false
Message-ID: <20050415075801.GA24974@elte.hu>
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* Jesper Juhl <juhl-lkml@dif.dk> wrote:

> As per this patch perhaps? : 
> 
> Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>

this is still not enough (there was one more comparison to cover). Also, 
it's a bit cleaner to just cast the left side to signed than cast every 
member separately.

	Ingo

--

fix signed comparisons of long long.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

--- linux/kernel/sched.c.orig
+++ linux/kernel/sched.c
@@ -2695,9 +2695,9 @@ need_resched_nonpreemptible:
 
 	schedstat_inc(rq, sched_cnt);
 	now = sched_clock();
-	if (likely((long long)now - prev->timestamp < NS_MAX_SLEEP_AVG)) {
+	if (likely((long long)(now - prev->timestamp) < NS_MAX_SLEEP_AVG)) {
 		run_time = now - prev->timestamp;
-		if (unlikely((long long)now - prev->timestamp < 0))
+		if (unlikely((long long)(now - prev->timestamp) < 0))
 			run_time = 0;
 	} else
 		run_time = NS_MAX_SLEEP_AVG;
@@ -2775,7 +2775,7 @@ go_idle:
 
 	if (!rt_task(next) && next->activated > 0) {
 		unsigned long long delta = now - next->timestamp;
-		if (unlikely((long long)now - next->timestamp < 0))
+		if (unlikely((long long)(now - next->timestamp) < 0))
 			delta = 0;
 
 		if (next->activated == 1)