From: Thomas Gleixner <tglx@linutronix.de>
To: Mike Galbraith <efault@gmx.de>,
linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>, x86@kernel.org
Subject: Re: [tip: timers/core] hrtimer: Consolidate reprogramming code
Date: Thu, 12 Aug 2021 16:32:41 +0200 [thread overview]
Message-ID: <877dgqivhy.ffs@tglx> (raw)
In-Reply-To: <87a6lmiwi0.ffs@tglx>
On Thu, Aug 12 2021 at 16:11, Thomas Gleixner wrote:
> On Thu, Aug 12 2021 at 09:19, Mike Galbraith wrote:
>> Greetings Peter, may your day get off to a better start than my box's
>> did :)
>>
>> On Tue, 2021-08-10 at 16:02 +0000, tip-bot2 for Peter Zijlstra wrote:
>>> The following commit has been merged into the timers/core branch of tip:
>>>
>>> Commit-ID: b14bca97c9f5c3e3f133445b01c723e95490d843
>>> Gitweb: https://git.kernel.org/tip/b14bca97c9f5c3e3f133445b01c723e95490d843
>>> Author: Peter Zijlstra <peterz@infradead.org>
>>> AuthorDate: Tue, 13 Jul 2021 15:39:47 +02:00
>>> Committer: Thomas Gleixner <tglx@linutronix.de>
>>> CommitterDate: Tue, 10 Aug 2021 17:57:22 +02:00
>>>
>>> hrtimer: Consolidate reprogramming code
>>
>> Per git-bisect, this is the tip.today commit that's bricking my box
>> early in boot.
>
> Let me stare at that.
Can you please test whether the below fixes it for you?
I have yet to find a machine which reproduces it as I really want to
understand which particular part is causing this.
Thanks,
tglx
---
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -652,24 +652,10 @@ static inline int hrtimer_hres_active(vo
return __hrtimer_hres_active(this_cpu_ptr(&hrtimer_bases));
}
-static void
-__hrtimer_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal,
- struct hrtimer *next_timer, ktime_t expires_next)
+static void __hrtimer_reprogram(struct hrtimer_cpu_base *cpu_base,
+ struct hrtimer *next_timer,
+ ktime_t expires_next)
{
- /*
- * If the hrtimer interrupt is running, then it will reevaluate the
- * clock bases and reprogram the clock event device.
- */
- if (cpu_base->in_hrtirq)
- return;
-
- if (expires_next > cpu_base->expires_next)
- return;
-
- if (skip_equal && expires_next == cpu_base->expires_next)
- return;
-
- cpu_base->next_timer = next_timer;
cpu_base->expires_next = expires_next;
/*
@@ -707,8 +693,10 @@ hrtimer_force_reprogram(struct hrtimer_c
expires_next = hrtimer_update_next_event(cpu_base);
- __hrtimer_reprogram(cpu_base, skip_equal, cpu_base->next_timer,
- expires_next);
+ if (skip_equal && expires_next == cpu_base->expires_next)
+ return;
+
+ __hrtimer_reprogram(cpu_base, cpu_base->next_timer, expires_next);
}
/* High resolution timer related functions */
@@ -863,7 +851,19 @@ static void hrtimer_reprogram(struct hrt
if (base->cpu_base != cpu_base)
return;
- __hrtimer_reprogram(cpu_base, true, timer, expires);
+ if (expires >= cpu_base->expires_next)
+ return;
+
+ /*
+ * If the hrtimer interrupt is running, then it will reevaluate the
+ * clock bases and reprogram the clock event device.
+ */
+ if (cpu_base->in_hrtirq)
+ return;
+
+ cpu_base->next_timer = timer;
+
+ __hrtimer_reprogram(cpu_base, timer, expires);
}
static bool update_needs_ipi(struct hrtimer_cpu_base *cpu_base,
next prev parent reply other threads:[~2021-08-12 14:32 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-13 13:39 [patch V2 00/10] hrtimer: Reprogramming and clock_was_set() overhaul Thomas Gleixner
2021-07-13 13:39 ` [patch V2 01/10] hrtimer: Avoid double reprogramming in __hrtimer_start_range_ns() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 02/10] hrtimer: Consolidate reprogramming code Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Peter Zijlstra
2021-08-12 7:19 ` Mike Galbraith
2021-08-12 14:11 ` Thomas Gleixner
2021-08-12 14:32 ` Thomas Gleixner [this message]
2021-08-12 15:04 ` Mike Galbraith
2021-08-12 15:22 ` Thomas Gleixner
2021-08-12 15:31 ` Mike Galbraith
2021-08-12 16:58 ` Thomas Gleixner
2021-08-12 15:27 ` Mike Galbraith
2021-08-12 20:32 ` [PATCH] hrtimer: Unbreak hrtimer_force_reprogram() Thomas Gleixner
2021-08-12 20:40 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-08-13 7:58 ` [PATCH] " Thomas Gleixner
2021-08-12 20:31 ` [PATCH] hrtimer: Use raw_cpu_ptr() in clock_was_set() Thomas Gleixner
2021-08-12 20:40 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-08-13 6:42 ` [PATCH] " Marek Szyprowski
[not found] ` <CGME20210812130945eucas1p117fc1e90f31c8d9fd177932cd1a18512@eucas1p1.samsung.com>
2021-08-12 13:09 ` [patch V2 02/10] hrtimer: Consolidate reprogramming code Marek Szyprowski
2021-07-13 13:39 ` [patch V2 03/10] hrtimer: Ensure timerfd notification for HIGHRES=n Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 04/10] hrtimer: Force clock_was_set() handling for the HIGHRES=n, NOHZ=y case Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 05/10] timerfd: Provide timerfd_resume() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 06/10] timekeeping: Distangle resume and clock-was-set events Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 07/10] time/timekeeping: Avoid invoking clock_was_set() twice Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 08/10] hrtimer: Add bases argument to clock_was_set() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 09/10] hrtimer: Avoid unnecessary SMP function calls in clock_was_set() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Marcelo Tosatti
2021-07-13 13:39 ` [patch V2 10/10] hrtimer: Avoid more " Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
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