revert "clocksource: make clocksource watchdog cycle through online CPUs" (3150e63d) · Commits · 戴 / test

Revert commit ("clocksource: make clocksource watchdog cycle through online CPUs") due to the regression reported by Gabriel C at http://lkml.org/lkml/2008/2/24/281 (short vesion: it makes TSC be marked as always unstable on his machine). Cc: Andi Kleen <ak@suse.de> Acked-by:

Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Robert Hancock <hancockr@shaw.ca> Acked-by:

Linus Torvalds <torvalds@linux-foundation.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Gabriel C <nix.or.die@googlemail.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

kernel/time/clocksource.c

+4 −10

Original line number	Diff line number	Diff line
		@@ -141,13 +141,8 @@ static void clocksource_watchdog(unsigned long data)
		}

		if (!list_empty(&watchdog_list)) {
		/* Cycle through CPUs to check if the CPUs stay synchronized to
		* each other. */
		int next_cpu = next_cpu(raw_smp_processor_id(), cpu_online_map);
		if (next_cpu >= NR_CPUS)
		next_cpu = first_cpu(cpu_online_map);
		watchdog_timer.expires += WATCHDOG_INTERVAL;
		add_timer_on(&watchdog_timer, next_cpu);
		__mod_timer(&watchdog_timer,
		watchdog_timer.expires + WATCHDOG_INTERVAL);
		}
		spin_unlock(&watchdog_lock);
		}
		@@ -169,7 +164,7 @@ static void clocksource_check_watchdog(struct clocksource *cs)
		if (!started && watchdog) {
		watchdog_last = watchdog->read();
		watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
		add_timer_on(&watchdog_timer, first_cpu(cpu_online_map));
		add_timer(&watchdog_timer);
		}
		} else {
		if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS)
		@@ -190,8 +185,7 @@ static void clocksource_check_watchdog(struct clocksource *cs)
		watchdog_last = watchdog->read();
		watchdog_timer.expires =
		jiffies + WATCHDOG_INTERVAL;
		add_timer_on(&watchdog_timer,
		first_cpu(cpu_online_map));
		add_timer(&watchdog_timer);
		}
		}
		}

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