All of lore.kernel.org
 help / color / mirror / Atom feed
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
Date: Fri, 15 Apr 2005 09:58:01 +0200	[thread overview]
Message-ID: <20050415075801.GA24974@elte.hu> (raw)
In-Reply-To: <Pine.LNX.4.62.0504150222390.3466@dragon.hyggekrogen.localhost>


* 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)

  parent reply	other threads:[~2005-04-15  7:58 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-04-14 23:49 [PATCH] sched: fix never executed code due to expression always false Jesper Juhl
2005-04-15  0:09 ` Nick Piggin
2005-04-15  0:14   ` Jesper Juhl
2005-04-15  0:13     ` Nick Piggin
2005-04-15  0:23       ` Jesper Juhl
2005-04-15  0:23         ` Nick Piggin
2005-04-15  2:32           ` Matt Mackall
2005-04-15  2:59         ` Herbert Xu
2005-04-15  3:25           ` Nick Piggin
2005-04-15  7:58         ` Ingo Molnar [this message]
2005-04-16 13:54           ` Jesper Juhl

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20050415075801.GA24974@elte.hu \
    --to=mingo@elte.hu \
    --cc=akpm@osdl.org \
    --cc=juhl-lkml@dif.dk \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nickpiggin@yahoo.com.au \
    --cc=rml@tech9.net \
    --cc=torvalds@osdl.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.