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From: Thomas Gleixner <tglx@linutronix.de>
To: Andrew Morton <akpm@osdl.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
John Stultz <johnstul@us.ibm.com>,
Arjan van de Veen <arjan@infradead.org>,
Roman Zippel <zippel@linux-m68k.org>
Subject: [patch 22/46] Extend next_timer_interrupt() to use a reference jiffie
Date: Tue, 23 Jan 2007 22:01:18 -0000 [thread overview]
Message-ID: <20070123211206.187512000@localhost.localdomain> (raw)
In-Reply-To: <20070123211159.178138000@localhost.localdomain>
[-- Attachment #1: dynticks-extend-next_timer_interrupt-to-use-a-reference-jiffie.patch --]
[-- Type: text/plain, Size: 3538 bytes --]
From: Thomas Gleixner <tglx@linutronix.de>
For CONFIG_NO_HZ we need to calculate the next timer wheel event based
on a given jiffie value. Extend the existing code to allow the extra
'now' argument. Provide a compability function for the existing
implementations to call the function with now == jiffies. (This also
solves the racyness of the original code vs. jiffies changing during
the iteration.)
No functional changes to existing users of this infrastructure.
[ remove WARN_ON() that triggered on s390, by Carsten Otte <cotte@de.ibm.com> ]
[ made new helper static, Adrian Bunk <bunk@stusta.de> ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
include/linux/timer.h | 10 ++++++++++
kernel/hrtimer.c | 2 +-
kernel/timer.c | 14 +++++++++++---
3 files changed, 22 insertions(+), 4 deletions(-)
Index: linux-2.6.20-rc4-mm1-bo/include/linux/timer.h
===================================================================
--- linux-2.6.20-rc4-mm1-bo.orig/include/linux/timer.h
+++ linux-2.6.20-rc4-mm1-bo/include/linux/timer.h
@@ -61,7 +61,17 @@ extern int del_timer(struct timer_list *
extern int __mod_timer(struct timer_list *timer, unsigned long expires);
extern int mod_timer(struct timer_list *timer, unsigned long expires);
+/*
+ * Return when the next timer-wheel timeout occurs (in absolute jiffies),
+ * locks the timer base:
+ */
extern unsigned long next_timer_interrupt(void);
+/*
+ * Return when the next timer-wheel timeout occurs (in absolute jiffies),
+ * locks the timer base and does the comparison against the given
+ * jiffie.
+ */
+extern unsigned long get_next_timer_interrupt(unsigned long now);
/***
* add_timer - start a timer
Index: linux-2.6.20-rc4-mm1-bo/kernel/hrtimer.c
===================================================================
--- linux-2.6.20-rc4-mm1-bo.orig/kernel/hrtimer.c
+++ linux-2.6.20-rc4-mm1-bo/kernel/hrtimer.c
@@ -533,7 +533,7 @@ ktime_t hrtimer_get_remaining(const stru
}
EXPORT_SYMBOL_GPL(hrtimer_get_remaining);
-#ifdef CONFIG_NO_IDLE_HZ
+#if defined(CONFIG_NO_IDLE_HZ) || defined(CONFIG_NO_HZ)
/**
* hrtimer_get_next_event - get the time until next expiry event
*
Index: linux-2.6.20-rc4-mm1-bo/kernel/timer.c
===================================================================
--- linux-2.6.20-rc4-mm1-bo.orig/kernel/timer.c
+++ linux-2.6.20-rc4-mm1-bo/kernel/timer.c
@@ -591,7 +591,7 @@ static inline void __run_timers(tvec_bas
spin_unlock_irq(&base->lock);
}
-#ifdef CONFIG_NO_IDLE_HZ
+#if defined(CONFIG_NO_IDLE_HZ) || defined(CONFIG_NO_HZ)
/*
* Find out when the next timer event is due to happen. This
* is used on S/390 to stop all activity when a cpus is idle.
@@ -687,10 +687,10 @@ static unsigned long cmp_next_hrtimer_ev
/**
* next_timer_interrupt - return the jiffy of the next pending timer
*/
-unsigned long next_timer_interrupt(void)
+unsigned long get_next_timer_interrupt(unsigned long now)
{
tvec_base_t *base = __get_cpu_var(tvec_bases);
- unsigned long expires, now = jiffies;
+ unsigned long expires;
spin_lock(&base->lock);
expires = __next_timer_interrupt(base);
@@ -701,6 +701,14 @@ unsigned long next_timer_interrupt(void)
return cmp_next_hrtimer_event(now, expires);
}
+
+#ifdef CONFIG_NO_IDLE_HZ
+unsigned long next_timer_interrupt(void)
+{
+ return get_next_timer_interrupt(jiffies);
+}
+#endif
+
#endif
/******************************************************************/
--
next prev parent reply other threads:[~2007-01-23 22:01 UTC|newest]
Thread overview: 78+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-01-23 22:00 [patch 00/46] High resolution timer / dynamic tick update Thomas Gleixner
2007-01-23 22:00 ` [patch 01/46] Add irq flag to disable balancing for an interrupt Thomas Gleixner
2007-01-23 22:00 ` [patch 02/46] Add a functions to handle interrupt affinity setting Thomas Gleixner
2007-01-23 22:00 ` [patch 03/46] [RFC] HZ free ntp Thomas Gleixner
2007-01-23 22:00 ` [patch 04/46] Uninline jiffies.h functions Thomas Gleixner
2007-01-23 22:01 ` [patch 05/46] Thomas Gleixner
2007-01-23 22:01 ` [patch 06/46] Fix timeout overflow with jiffies Thomas Gleixner
2007-01-23 22:01 ` [patch 07/46] GTOD: persistent clock support Thomas Gleixner
2007-01-23 22:01 ` [patch 08/46] i386: use GTOD " Thomas Gleixner
2007-01-23 22:01 ` [patch 09/46] i386 Remove useless code in tsc.c Thomas Gleixner
2007-01-23 22:01 ` [patch 10/46] Simplify the registration of clocksources Thomas Gleixner
2007-01-23 22:01 ` [patch 11/46] x86: rewrite SMP TSC sync code Thomas Gleixner
2007-01-23 22:01 ` [patch 12/46] clocksource: replace is_continuous by a flag field Thomas Gleixner
2007-01-24 11:23 ` [patch] clocksource: fixup is_continous changes in vmitime.c Ingo Molnar
2007-01-24 11:53 ` Thomas Gleixner
2007-01-23 22:01 ` [patch 13/46] clocksource: fixup is_continous changes on ARM Thomas Gleixner
2007-01-23 22:01 ` [patch 14/46] clocksource: fixup is_continous changes on AVR32 Thomas Gleixner
2007-01-23 22:01 ` [patch 15/46] clocksource: fixup is_continous changes on S390 Thomas Gleixner
2007-01-23 22:01 ` [patch 16/46] clocksource: fixup is_continous changes on MIPS Thomas Gleixner
2007-01-23 22:01 ` [patch 17/46] clocksource: Remove the update callback Thomas Gleixner
2007-01-23 22:01 ` [patch 18/46] clocksource: Add verification (watchdog) helper Thomas Gleixner
2007-01-24 15:42 ` [patch] clocksource: add verification (watchdog) helper, fix Ingo Molnar
2007-01-23 22:01 ` [patch 19/46] Mark TSC on GeodeLX reliable Thomas Gleixner
2007-01-23 22:01 ` [patch 20/46] uninline irq_enter() Thomas Gleixner
2007-01-23 22:01 ` [patch 21/46] Fix cascade lookup of next_timer_interrupt Thomas Gleixner
2007-01-23 22:01 ` Thomas Gleixner [this message]
2007-01-23 22:01 ` [patch 23/46] hrtimers: namespace and enum cleanup Thomas Gleixner
2007-01-23 22:01 ` [patch 24/46] hrtimers: namespace and enum cleanup vs. git-input Thomas Gleixner
2007-01-23 22:01 ` [patch 25/46] hrtimers: cleanup locking Thomas Gleixner
2007-01-23 22:01 ` [patch 26/46] hrtimers; add state tracking Thomas Gleixner
2007-01-23 22:01 ` [patch 27/46] hrtimers: clean up callback tracking Thomas Gleixner
2007-01-23 22:01 ` [patch 28/46] hrtimers: move and add documentation Thomas Gleixner
2007-01-23 22:01 ` [patch 29/46] ACPI: fix missing include for UP Thomas Gleixner
2007-01-23 22:01 ` [patch 30/46] ACPI keep track of timer broadcasting Thomas Gleixner
2007-01-23 22:01 ` [patch 31/46] Allow early access to the power management timer Thomas Gleixner
2007-01-23 22:01 ` [patch 32/46] i386, apic: clean up the APIC code Thomas Gleixner
2007-01-23 22:01 ` [patch 33/46] clockevents: add core functionality Thomas Gleixner
2007-01-23 22:01 ` [patch 34/46] tick-management: " Thomas Gleixner
2007-01-23 22:01 ` [patch 35/46] tick-management: broadcast functionality Thomas Gleixner
2007-01-23 22:01 ` [patch 36/46] tick-management: dyntick / highres functionality Thomas Gleixner
2007-01-28 2:03 ` [PATCH] high_res_timers: precisely update_process_times; " Karsten Wiese
2007-01-23 22:01 ` [patch 37/46] clockevents: i383 drivers Thomas Gleixner
2007-01-23 22:01 ` [patch 38/46] i386 rework local apic timer calibration Thomas Gleixner
2007-01-23 22:01 ` [patch 39/46] i386 prepare for dyntick Thomas Gleixner
2007-01-23 22:01 ` [patch 40/46] i386 prepare nmi watchdog for dynticks Thomas Gleixner
2007-01-23 22:01 ` [patch 41/46] i386: enable dynticks in kconfig Thomas Gleixner
2007-01-23 22:01 ` [patch 42/46] hrtimers: add high resolution timer support Thomas Gleixner
2007-01-23 22:01 ` [patch 43/46] hrtimers: prevent possible itimer DoS Thomas Gleixner
2007-01-23 22:01 ` [patch 44/46] Add debugging feature /proc/timer_stat Thomas Gleixner
2007-01-23 22:01 ` [patch 45/46] Add debugging feature /proc/timer_list Thomas Gleixner
2007-01-23 22:01 ` [patch 46/46] Add SysRq-Q to print timer_list debug info Thomas Gleixner
2007-01-24 2:16 ` [patch 00/46] High resolution timer / dynamic tick update Daniel Walker
2007-01-24 2:23 ` Andrew Morton
2007-01-24 3:25 ` Daniel Walker
2007-01-24 7:07 ` Ingo Molnar
2007-01-24 9:30 ` Daniel Walker
2007-01-24 9:51 ` Ingo Molnar
2007-01-24 10:23 ` Daniel Walker
2007-01-24 10:29 ` Ingo Molnar
2007-01-24 10:53 ` Daniel Walker
2007-01-24 11:04 ` Ingo Molnar
2007-01-24 11:13 ` Thomas Gleixner
2007-01-24 15:53 ` Daniel Walker
[not found] ` <20070124160046.GA24798@elte.hu>
2007-01-24 17:21 ` Daniel Walker
[not found] ` <1169655076.19471.241.camel@imap.mvista.com>
2007-01-24 19:38 ` Ingo Molnar
2007-01-24 20:09 ` Daniel Walker
2007-01-24 20:13 ` Ingo Molnar
2007-01-24 19:57 ` john stultz
2007-01-24 20:51 ` Daniel Walker
2007-01-24 21:23 ` john stultz
2007-01-24 21:37 ` Daniel Walker
2007-01-25 6:10 ` Ingo Molnar
2007-01-25 6:37 ` Ingo Molnar
2007-01-25 6:32 ` Ingo Molnar
2007-01-25 16:38 ` Daniel Walker
2007-01-28 2:17 ` Andrew Morton
2007-01-29 21:31 ` john stultz
2007-01-29 21:45 ` john stultz
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