From: Nicolas Pitre <nicolas.pitre@linaro.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org, mingo@kernel.org,
tglx@linutronix.de, Linux PM list <linux-pm@vger.kernel.org>,
Russell King <rmk+kernel@arm.linux.org.uk>
Subject: Re: [PATCH 09/09] arm: bl_switcher: Kill tick suspend hackery
Date: Wed, 25 Mar 2015 08:34:12 -0400 (EDT) [thread overview]
Message-ID: <alpine.LFD.2.11.1503250833420.27567@knanqh.ubzr> (raw)
In-Reply-To: <1655112.Ws17YsMfN7@vostro.rjw.lan>
On Wed, 25 Mar 2015, Rafael J. Wysocki wrote:
> From: Thomas Gleixner <tglx@linutronix.de>
>
> Use the new tick_suspend/resume_local() and get rid of the homebrewn
> implementation of these in the ARM bL switcher. The check for the
> cpumask is completely pointless. There is no harm to suspend a per
> cpu tick device unconditionally. If that's a real issue then we fix
> it proper at the core level and not with some completely undocumented
> hacks in some random core code.
>
> Move the tick internals to the core code, now that this nuisance is
> gone.
>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
> Cc: Russell King <rmk+kernel@arm.linux.org.uk>
> [ rjw: Rebase, changelog ]
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
> ---
> arch/arm/common/bL_switcher.c | 16 ++--------------
> include/linux/clockchips.h | 6 ------
> include/linux/tick.h | 19 ++++---------------
> kernel/time/tick-common.c | 2 +-
> kernel/time/tick-internal.h | 5 +++++
> kernel/time/tick-sched.h | 10 ++++++++++
> 6 files changed, 22 insertions(+), 36 deletions(-)
>
> Index: linux-pm/include/linux/tick.h
> ===================================================================
> --- linux-pm.orig/include/linux/tick.h
> +++ linux-pm/include/linux/tick.h
> @@ -11,30 +11,19 @@
> #include <linux/cpumask.h>
> #include <linux/sched.h>
>
> -/* ARM BL switcher abuse support */
> -#ifdef CONFIG_GENERIC_CLOCKEVENTS
> -enum tick_device_mode {
> - TICKDEV_MODE_PERIODIC,
> - TICKDEV_MODE_ONESHOT,
> -};
> -
> -struct tick_device {
> - struct clock_event_device *evtdev;
> - enum tick_device_mode mode;
> -};
> -extern struct tick_device *tick_get_device(int cpu);
> -#endif
> -
> #ifdef CONFIG_GENERIC_CLOCKEVENTS
> extern void __init tick_init(void);
> extern void tick_freeze(void);
> extern void tick_unfreeze(void);
> -/* Should be core only, but XEN resume magic requires this */
> +/* Should be core only, but ARM BL switcher requires it */
> +extern void tick_suspend_local(void);
> +/* Should be core only, but XEN resume magic and ARM BL switcher require it */
> extern void tick_resume_local(void);
> #else /* CONFIG_GENERIC_CLOCKEVENTS */
> static inline void tick_init(void) { }
> static inline void tick_freeze(void) { }
> static inline void tick_unfreeze(void) { }
> +static inline void tick_suspend_local(void) { }
> static inline void tick_resume_local(void) { }
> #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
>
> Index: linux-pm/arch/arm/common/bL_switcher.c
> ===================================================================
> --- linux-pm.orig/arch/arm/common/bL_switcher.c
> +++ linux-pm/arch/arm/common/bL_switcher.c
> @@ -151,8 +151,6 @@ static int bL_switch_to(unsigned int new
> unsigned int mpidr, this_cpu, that_cpu;
> unsigned int ob_mpidr, ob_cpu, ob_cluster, ib_mpidr, ib_cpu, ib_cluster;
> struct completion inbound_alive;
> - struct tick_device *tdev;
> - enum clock_event_mode tdev_mode;
> long volatile *handshake_ptr;
> int ipi_nr, ret;
>
> @@ -219,13 +217,7 @@ static int bL_switch_to(unsigned int new
> /* redirect GIC's SGIs to our counterpart */
> gic_migrate_target(bL_gic_id[ib_cpu][ib_cluster]);
>
> - tdev = tick_get_device(this_cpu);
> - if (tdev && !cpumask_equal(tdev->evtdev->cpumask, cpumask_of(this_cpu)))
> - tdev = NULL;
> - if (tdev) {
> - tdev_mode = tdev->evtdev->mode;
> - clockevents_set_mode(tdev->evtdev, CLOCK_EVT_MODE_SHUTDOWN);
> - }
> + tick_suspend_local();
>
> ret = cpu_pm_enter();
>
> @@ -251,11 +243,7 @@ static int bL_switch_to(unsigned int new
>
> ret = cpu_pm_exit();
>
> - if (tdev) {
> - clockevents_set_mode(tdev->evtdev, tdev_mode);
> - clockevents_program_event(tdev->evtdev,
> - tdev->evtdev->next_event, 1);
> - }
> + tick_resume_local();
>
> trace_cpu_migrate_finish(ktime_get_real_ns(), ib_mpidr);
> local_fiq_enable();
> Index: linux-pm/include/linux/clockchips.h
> ===================================================================
> --- linux-pm.orig/include/linux/clockchips.h
> +++ linux-pm/include/linux/clockchips.h
> @@ -163,12 +163,6 @@ clockevents_calc_mult_shift(struct clock
> freq, minsec);
> }
>
> -/* Should be core only, but is abused by arm bl_switcher */
> -extern void clockevents_set_mode(struct clock_event_device *dev,
> - enum clock_event_mode mode);
> -extern int clockevents_program_event(struct clock_event_device *dev,
> - ktime_t expires, bool force);
> -
> extern void clockevents_suspend(void);
> extern void clockevents_resume(void);
>
> Index: linux-pm/kernel/time/tick-internal.h
> ===================================================================
> --- linux-pm.orig/kernel/time/tick-internal.h
> +++ linux-pm/kernel/time/tick-internal.h
> @@ -28,6 +28,7 @@ extern bool tick_check_replacement(struc
> struct clock_event_device *newdev);
> extern void tick_install_replacement(struct clock_event_device *dev);
> extern int tick_is_oneshot_available(void);
> +extern struct tick_device *tick_get_device(int cpu);
>
> /* Check, if the device is functional or a dummy for broadcast */
> static inline int tick_device_is_functional(struct clock_event_device *dev)
> @@ -38,6 +39,10 @@ static inline int tick_device_is_functio
> extern void clockevents_shutdown(struct clock_event_device *dev);
> extern void clockevents_exchange_device(struct clock_event_device *old,
> struct clock_event_device *new);
> +extern void clockevents_set_mode(struct clock_event_device *dev,
> + enum clock_event_mode mode);
> +extern int clockevents_program_event(struct clock_event_device *dev,
> + ktime_t expires, bool force);
> extern void clockevents_handle_noop(struct clock_event_device *dev);
> extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
> extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
> Index: linux-pm/kernel/time/tick-sched.h
> ===================================================================
> --- linux-pm.orig/kernel/time/tick-sched.h
> +++ linux-pm/kernel/time/tick-sched.h
> @@ -3,6 +3,16 @@
>
> #include <linux/hrtimer.h>
>
> +enum tick_device_mode {
> + TICKDEV_MODE_PERIODIC,
> + TICKDEV_MODE_ONESHOT,
> +};
> +
> +struct tick_device {
> + struct clock_event_device *evtdev;
> + enum tick_device_mode mode;
> +};
> +
> enum tick_nohz_mode {
> NOHZ_MODE_INACTIVE,
> NOHZ_MODE_LOWRES,
> Index: linux-pm/kernel/time/tick-common.c
> ===================================================================
> --- linux-pm.orig/kernel/time/tick-common.c
> +++ linux-pm/kernel/time/tick-common.c
> @@ -379,7 +379,7 @@ void tick_shutdown(unsigned int *cpup)
> *
> * No locks required. Nothing can change the per cpu device.
> */
> -static void tick_suspend_local(void)
> +void tick_suspend_local(void)
> {
> struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
>
>
>
next prev parent reply other threads:[~2015-03-25 12:34 UTC|newest]
Thread overview: 106+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-16 12:14 [PATCH 00/35] Some kernel/time cleanups Peter Zijlstra
2015-02-16 12:14 ` [PATCH 01/35] ACPI/acpi_pad: Remove the local apic nonsense Peter Zijlstra
2015-02-16 18:54 ` Rafael J. Wysocki
2015-02-18 6:16 ` Rafael J. Wysocki
2015-02-16 12:14 ` [PATCH 02/35] clockevents: Remove CONFIG_GENERIC_CLOCKEVENTS_BUILD Peter Zijlstra
2015-02-16 12:14 ` [PATCH 03/35] tick: Cleanup internal header files Peter Zijlstra
2015-02-16 12:14 ` [PATCH 04/35] tick: Cleanup internal header file Peter Zijlstra
2015-02-16 12:14 ` [PATCH 05/35] tick: Move core only declarations and functions to core Peter Zijlstra
2015-02-16 12:14 ` [PATCH 06/35] clockevents: Remove extra local_irq_save in clockevents_exchange_device() Peter Zijlstra
2015-02-16 12:14 ` [PATCH 07/35] clockevents: Make suspend/resume calls explicit Peter Zijlstra
2015-02-16 19:07 ` Rafael J. Wysocki
2015-02-16 12:14 ` [PATCH 08/35] tick: Make tick_resume_broadcast_oneshot static Peter Zijlstra
2015-02-16 12:14 ` [PATCH 09/35] tick/xen: Provide and use tick_resume_local() Peter Zijlstra
2015-02-16 16:37 ` David Vrabel
2015-02-16 12:14 ` [PATCH 10/35] clockevents: Make tick handover explicit Peter Zijlstra
2015-02-16 12:14 ` [PATCH 11/35] clockevents: Cleanup dead cpu explicitely Peter Zijlstra
2015-02-16 12:14 ` [PATCH 12/35] clockevents: Provide explicit broadcast control function Peter Zijlstra
2015-02-23 18:08 ` Daniel Lezcano
2015-02-24 0:38 ` Tony Lindgren
2015-02-16 12:14 ` [PATCH 13/35] x86, amd_idle: Use explicit broadcast control functions Peter Zijlstra
2015-02-16 12:14 ` [PATCH 14/35] ACPI / PAD: Use explicit broadcast control function Peter Zijlstra
2015-02-16 12:14 ` [PATCH 15/35] ACPI/ processor_idle: Use explicit broadcast controll function Peter Zijlstra
2015-02-16 12:14 ` [PATCH 16/35] cpuidle: Use explicit broadcast control function Peter Zijlstra
2015-02-23 18:11 ` Daniel Lezcano
2015-02-16 12:14 ` [PATCH 17/35] intel_idle: " Peter Zijlstra
2015-02-16 12:14 ` [PATCH 18/35] ARM: OMAP: " Peter Zijlstra
2015-02-24 0:40 ` Tony Lindgren
2015-02-16 12:14 ` [PATCH 19/35] clockevents: Remove the broadcast control leftovers Peter Zijlstra
2015-02-16 12:14 ` [PATCH 20/35] clockevents: Provide explicit broadcast oneshot control function Peter Zijlstra
2015-02-24 0:41 ` Tony Lindgren
2015-02-16 12:14 ` [PATCH 21/35] x86, amd_idle: Use explicit broadcast oneshot control functions Peter Zijlstra
2015-02-16 12:14 ` [PATCH 22/35] ACPI / PAD: Use explicit broadcast oneshot control function Peter Zijlstra
2015-02-16 12:14 ` [PATCH 23/35] ACPI/ processor_idle: Use explicit broadcast oneshot controll function Peter Zijlstra
2015-02-16 12:14 ` [PATCH 24/35] intel_idle: Use explicit broadcast oneshot control function Peter Zijlstra
2015-02-16 12:15 ` [PATCH 25/35] ARM: OMAP: " Peter Zijlstra
2015-02-24 0:41 ` Tony Lindgren
2015-02-16 12:15 ` [PATCH 26/35] ARM: tegra: " Peter Zijlstra
2015-02-16 12:15 ` [PATCH 27/35] sched/idle: " Peter Zijlstra
2015-02-21 0:56 ` Nicolas Pitre
2015-02-21 11:19 ` Peter Zijlstra
2015-02-16 12:15 ` [PATCH 28/35] clockevents: Remove the broadcast oneshot control leftovers Peter Zijlstra
2015-02-16 12:15 ` [PATCH 29/35] tick/timekeeping: Make PM_SLEEP related code conditional Peter Zijlstra
2015-02-16 12:15 ` [PATCH 30/35] timekeeping: Get rid of stale comment Peter Zijlstra
2015-02-16 12:15 ` [PATCH 31/35] clockevents: Consolidate tick_shutdown() Peter Zijlstra
2015-02-16 12:15 ` [PATCH 32/35] clockevents: Fix cpu down race for hrtimer based broadcasting Peter Zijlstra
2015-02-17 4:03 ` Preeti U Murthy
2015-02-17 10:39 ` Peter Zijlstra
2015-02-18 3:10 ` Preeti U Murthy
2015-02-18 13:06 ` Peter Zijlstra
2015-02-19 7:01 ` Preeti U Murthy
2015-02-19 9:53 ` Peter Zijlstra
2015-02-19 17:51 ` Nicolas Pitre
2015-02-21 12:46 ` Peter Zijlstra
2015-02-21 17:45 ` Nicolas Pitre
2015-02-23 16:14 ` Peter Zijlstra
2015-02-23 16:32 ` Nicolas Pitre
2015-02-23 17:33 ` Nicolas Pitre
2015-02-26 5:31 ` Preeti U Murthy
2015-02-27 8:49 ` Preeti U Murthy
2015-03-02 14:56 ` Peter Zijlstra
2015-03-05 4:20 ` Preeti U Murthy
2015-03-29 6:45 ` Ingo Molnar
2015-03-16 4:52 ` Preeti U Murthy
2015-03-25 5:32 ` Preeti U Murthy
2015-02-16 12:15 ` [PATCH 33/35] tick: Make hrtimer broadcasting opt-in Peter Zijlstra
2015-02-17 3:06 ` Preeti U Murthy
2015-02-17 10:04 ` Lorenzo Pieralisi
2015-02-16 12:15 ` [PATCH 34/35] tick: Provide tick_suspend_local() Peter Zijlstra
2015-02-17 14:31 ` Lorenzo Pieralisi
2015-02-17 17:55 ` Nicolas Pitre
2015-02-17 21:29 ` Nicolas Pitre
2015-02-18 13:35 ` Peter Zijlstra
2015-02-18 16:22 ` Rafael J. Wysocki
2015-02-18 16:38 ` Lorenzo Pieralisi
2015-02-16 12:15 ` [PATCH 35/35] arm: bl_switcher: Kill tick suspend hackery Peter Zijlstra
2015-02-16 19:14 ` [PATCH 00/35] Some kernel/time cleanups Rafael J. Wysocki
2015-03-25 12:04 ` [PATCH 00/09] Some kernel/time cleanups (related to timer_suspend/resume) Rafael J. Wysocki
2015-03-25 12:05 ` [PATCH 01/09] clockevents: Remove CONFIG_GENERIC_CLOCKEVENTS_BUILD Rafael J. Wysocki
2015-04-02 12:28 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-03-25 12:06 ` [PATCH 02/09] tick: Move clocksource related stuff to timekeeping.h Rafael J. Wysocki
2015-04-02 12:28 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-03-25 12:06 ` [PATCH 03/09] tick: Simplify tick-internal.h Rafael J. Wysocki
2015-04-02 12:29 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-03-25 12:07 ` [PATCH 04/09] tick: Move core only declarations and functions to core Rafael J. Wysocki
2015-04-02 12:29 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-03-25 12:08 ` [PATCH 05/09] clockevents: Remove extra local_irq_save in clockevents_exchange_device() Rafael J. Wysocki
2015-04-02 12:29 ` [tip:timers/core] clockevents: Remove extra local_irq_save() " tip-bot for Thomas Gleixner
2015-03-25 12:09 ` [PATCH 06/09] clockevents: Make suspend/resume calls explicit Rafael J. Wysocki
2015-04-02 12:30 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-03-25 12:09 ` [PATCH 07/09] tick: Make tick_resume_broadcast_oneshot static Rafael J. Wysocki
2015-04-02 12:30 ` [tip:timers/core] tick: Make tick_resume_broadcast_oneshot() static tip-bot for Thomas Gleixner
2015-03-25 12:11 ` [PATCH 08/09] tick/xen: Provide and use tick_suspend_local() and tick_resume_local() Rafael J. Wysocki
2015-03-25 20:13 ` Konrad Rzeszutek Wilk
2015-03-25 20:57 ` Rafael J. Wysocki
2015-03-25 20:44 ` Konrad Rzeszutek Wilk
2015-03-25 21:36 ` Rafael J. Wysocki
2015-04-02 12:30 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 13:21 ` [PATCH][fix for tip/timers/core] timers / PM: Fix up tick_unfreeze() Rafael J. Wysocki
2015-04-03 13:18 ` [tip:timers/core] timers/PM: " tip-bot for Rafael J. Wysocki
2015-04-03 13:31 ` [PATCH][cleanup for tip/timers/core] timers / PM: Drop unnecessary braces from tick_freeze() Rafael J. Wysocki
2015-04-03 13:18 ` [tip:timers/core] timers/PM: " tip-bot for Rafael J. Wysocki
2015-03-25 12:11 ` [PATCH 09/09] arm: bl_switcher: Kill tick suspend hackery Rafael J. Wysocki
2015-03-25 12:34 ` Nicolas Pitre [this message]
2015-04-02 12:30 ` [tip:timers/core] arm/bL_switcher: " tip-bot for Thomas Gleixner
2015-03-25 12:13 ` [PATCH 00/09] Some kernel/time cleanups (related to timer_suspend/resume) Rafael J. Wysocki
2015-03-31 22:45 ` [GIT PULL] kernel/time cleanups (related to tick_suspend/resume) Rafael J. Wysocki
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