Conflicts: drivers/video/mxc/ldb.c
export usb_suspend, usb_resume, and pm_mutex Signed-off-by: Peter Chen <peter.chen@freescale.com>
There are so many retries happen on the per-cpu event device
when run the command 'cat /proc/timer_list', as following:
root@~$ cat /proc/timer_list
Timer List Version: v0.6
HRTIMER_MAX_CLOCK_BASES: 3
now at 3297691988044 nsecs
Tick Device: mode: 1
Per CPU device: 0
Clock Event Device: local_timer
max_delta_ns: 8624432320
min_delta_ns: 1000
mult: 2138893713
shift: 32
mode: 3
next_event: 3297700000000 nsecs
set_next_event: twd_set_next_event
set_mode: twd_set_mode
event_handler: hrtimer_interrupt
retries: 36383
the reason is that the local timer will stop when enter C3 state,
we need switch the local timer to bc timer when enter the state
and switch back when exit from the that state.The code is like this:
void arch_idle(void)
{
....
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu);
enter_the_wait_mode();
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu);
}
when the broadcast timer interrupt arrives(this interrupt just wakeup
the ARM, and ARM has no chance to handle it since local irq is disabled.
In fact it's disabled in cpu_idle() of arch/arm/kernel/process.c)
the broadcast timer interrupt will wake up the CPU and run:
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); ->
tick_broadcast_oneshot_control(...);
->
tick_program_event(dev->next_event, 1);
->
tick_dev_program_event(dev, expires, force);
->
for (i = 0;;) {
int ret = clockevents_program_event(dev, expires, now);
if (!ret || !force)
return ret;
dev->retries++;
....
now = ktime_get();
expires = ktime_add_ns(now, dev->min_delta_ns);
}
clockevents_program_event(dev, expires, now);
delta = ktime_to_ns(ktime_sub(expires, now));
if (delta <= 0)
return -ETIME;
when the bc timer interrupt arrives, which means the last local timer
expires too. so, clockevents_program_event will return -ETIME, which will
cause the dev->retries++ when retry to program the expired timer.
Even under the worst case, after the re-program the expired timer,
then CPU enter idle quickly before the re-progam timer expired,
it will make system ping-pang forever if no interrupt happen.
We have found the ping-pang issue during the video play-back test.
system will freeze and video not playing for sometime until other interrupt
occured to break the error condition.
The detailed information, please refer to the LKML:https://lkml.org/lkml/2013/2/20/216
which posted by Jason Liu.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jason Liu <r64343@freescale.com>
Tested-by: Jason Liu <r64343@freescale.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Conflicts: arch/arm/configs/imx6_defconfig arch/arm/configs/imx6_updater_defconfig arch/arm/configs/imx6s_defconfig arch/arm/include/asm/dma-mapping.h arch/arm/kernel/smp.c arch/arm/mach-mx6/Kconfig arch/arm/mach-mx6/board-mx6dl_arm2.h arch/arm/mach-mx6/board-mx6dl_sabresd.h arch/arm/mach-mx6/board-mx6q_arm2.c arch/arm/mach-mx6/board-mx6q_arm2.h arch/arm/mach-mx6/board-mx6q_sabreauto.c arch/arm/mach-mx6/board-mx6q_sabreauto.h arch/arm/mach-mx6/board-mx6q_sabrelite.c arch/arm/mach-mx6/board-mx6q_sabresd.c arch/arm/mach-mx6/board-mx6q_sabresd.h arch/arm/mach-mx6/board-mx6sl_arm2.c arch/arm/mach-mx6/board-mx6sl_arm2.h arch/arm/mach-mx6/board-mx6solo_sabreauto.h arch/arm/mach-mx6/bus_freq.c arch/arm/mach-mx6/clock.c arch/arm/mach-mx6/clock_mx6sl.c arch/arm/mach-mx6/cpu.c arch/arm/mach-mx6/crm_regs.h arch/arm/mach-mx6/devices-imx6q.h arch/arm/mach-mx6/devices.c arch/arm/mach-mx6/mx6_anatop_regulator.c arch/arm/mach-mx6/pcie.c arch/arm/mach-mx6/system.c arch/arm/mm/dma-mapping.c arch/arm/plat-mxc/devices/Makefile arch/arm/plat-mxc/devices/platform-imx-dcp.c arch/arm/plat-mxc/devices/platform-imx-ocotp.c arch/arm/plat-mxc/devices/platform-imx-rngb.c arch/arm/plat-mxc/devices/platform-mxc_hdmi.c arch/arm/plat-mxc/include/mach/devices-common.h arch/arm/plat-mxc/include/mach/esdhc.h arch/arm/plat-mxc/include/mach/iomux-mx6dl.h arch/arm/plat-mxc/include/mach/iomux-mx6q.h arch/arm/plat-mxc/include/mach/memory.h arch/arm/plat-mxc/include/mach/mx6.h arch/arm/plat-mxc/include/mach/mxc_edid.h arch/arm/plat-mxc/include/mach/mxc_hdmi.h arch/arm/plat-mxc/system.c drivers/Kconfig drivers/char/hw_random/fsl-rngc.c drivers/cpufreq/Makefile drivers/cpufreq/cpufreq_interactive.c drivers/crypto/Kconfig drivers/crypto/caam/caamalg.c drivers/crypto/caam/compat.h drivers/crypto/caam/ctrl.c drivers/crypto/caam/desc_constr.h drivers/crypto/caam/intern.h drivers/crypto/dcp.c drivers/dma/pch_dma.c drivers/input/keyboard/gpio_keys.c drivers/input/touchscreen/egalax_ts.c drivers/input/touchscreen/max11801_ts.c drivers/media/video/mxc/capture/Kconfig drivers/media/video/mxc/capture/adv7180.c drivers/media/video/mxc/capture/ipu_csi_enc.c drivers/media/video/mxc/capture/ipu_prp_vf_sdc.c drivers/media/video/mxc/capture/ipu_prp_vf_sdc_bg.c drivers/media/video/mxc/capture/mxc_v4l2_capture.c drivers/media/video/mxc/capture/ov5640_mipi.c drivers/media/video/mxc/output/mxc_vout.c drivers/misc/Kconfig drivers/misc/Makefile drivers/mmc/card/block.c drivers/mmc/core/mmc.c drivers/mmc/host/mmci.c drivers/mmc/host/sdhci-esdhc-imx.c drivers/mmc/host/sdhci.c drivers/mmc/host/sdhci.h drivers/mxc/Kconfig drivers/mxc/Makefile drivers/mxc/asrc/mxc_asrc.c drivers/mxc/gpu-viv/arch/XAQ2/hal/kernel/gc_hal_kernel_context.c drivers/mxc/gpu-viv/arch/XAQ2/hal/kernel/gc_hal_kernel_hardware.c drivers/mxc/gpu-viv/hal/kernel/gc_hal_kernel.c drivers/mxc/gpu-viv/hal/kernel/gc_hal_kernel.h drivers/mxc/gpu-viv/hal/kernel/gc_hal_kernel_command.c drivers/mxc/gpu-viv/hal/kernel/gc_hal_kernel_event.c drivers/mxc/gpu-viv/hal/kernel/inc/gc_hal.h drivers/mxc/gpu-viv/hal/kernel/inc/gc_hal_base.h drivers/mxc/gpu-viv/hal/kernel/inc/gc_hal_options.h drivers/mxc/gpu-viv/hal/os/linux/kernel/gc_hal_kernel_os.c drivers/mxc/ipu3/ipu_device.c drivers/mxc/vpu/mxc_vpu.c drivers/net/fec.c drivers/net/wireless/Makefile drivers/power/sabresd_battery.c drivers/regulator/core.c drivers/tty/serial/imx.c drivers/usb/core/hub.c drivers/usb/gadget/arcotg_udc.c drivers/usb/gadget/fsl_updater.c drivers/usb/gadget/inode.c drivers/usb/host/ehci-hub.c drivers/video/mxc/ldb.c drivers/video/mxc/mipi_dsi.c drivers/video/mxc/mxc_dispdrv.c drivers/video/mxc/mxc_dispdrv.h drivers/video/mxc/mxc_edid.c drivers/video/mxc/mxc_elcdif_fb.c drivers/video/mxc/mxc_ipuv3_fb.c drivers/video/mxc/mxc_spdc_fb.c drivers/video/mxc_hdmi.c drivers/watchdog/imx2_wdt.c fs/proc/base.c include/linux/mmc/host.h include/linux/mmc/sdhci.h include/linux/mxc_v4l2.h kernel/power/main.c sound/soc/codecs/mxc_hdmi.c sound/soc/codecs/mxc_spdif.c sound/soc/codecs/wm8962.c sound/soc/imx/Kconfig sound/soc/imx/Makefile sound/soc/imx/imx-cs42888.c sound/soc/imx/imx-esai.c sound/soc/imx/imx-wm8958.c sound/soc/imx/imx-wm8962.c
When performing cpu hotplug tests the kernel printk log buffer gets flooded with pointless "Switched to NOHz mode..." messages. Especially when afterwards analyzing a dump this might have removed more interesting stuff out of the buffer. Assuming that switching to NOHz mode simply works just remove the printk. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Link: http://lkml.kernel.org/r/20110823112046.GB2540@osiris.boeblingen.de.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Stepan found:
CPU0 CPUn
_cpu_up()
__cpu_up()
boostrap()
notify_cpu_starting()
set_cpu_online()
while (!cpu_active())
cpu_relax()
<PREEMPT-out>
smp_call_function(.wait=1)
/* we find cpu_online() is true */
arch_send_call_function_ipi_mask()
/* wait-forever-more */
<PREEMPT-in>
local_irq_enable()
cpu_notify(CPU_ONLINE)
sched_cpu_active()
set_cpu_active()
Now the purpose of cpu_active is mostly with bringing down a cpu, where
we mark it !active to avoid the load-balancer from moving tasks to it
while we tear down the cpu. This is required because we only update the
sched_domain tree after we brought the cpu-down. And this is needed so
that some tasks can still run while we bring it down, we just don't want
new tasks to appear.
On cpu-up however the sched_domain tree doesn't yet include the new cpu,
so its invisible to the load-balancer, regardless of the active state.
So instead of setting the active state after we boot the new cpu (and
consequently having to wait for it before enabling interrupts) set the
cpu active before we set it online and avoid the whole mess.
Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
No need to assign ret in each case and break. Simply return the result of the handler function directly. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Huang Shijie <b32955@freescale.com>
cpufreq: interactive: New 'interactive' governor
This governor is designed for latency-sensitive workloads, such as
interactive user interfaces. The interactive governor aims to be
significantly more responsive to ramp CPU quickly up when CPU-intensive
activity begins.
Existing governors sample CPU load at a particular rate, typically
every X ms. This can lead to under-powering UI threads for the period of
time during which the user begins interacting with a previously-idle system
until the next sample period happens.
The 'interactive' governor uses a different approach. Instead of sampling
the CPU at a specified rate, the governor will check whether to scale the
CPU frequency up soon after coming out of idle. When the CPU comes out of
idle, a timer is configured to fire within 1-2 ticks. If the CPU is very
busy from exiting idle to when the timer fires then we assume the CPU is
underpowered and ramp to MAX speed.
If the CPU was not sufficiently busy to immediately ramp to MAX speed, then
the governor evaluates the CPU load since the last speed adjustment,
choosing the highest value between that longer-term load or the short-term
load since idle exit to determine the CPU speed to ramp to.
A realtime thread is used for scaling up, giving the remaining tasks the
CPU performance benefit, unlike existing governors which are more likely to
schedule rampup work to occur after your performance starved tasks have
completed.
The tuneables for this governor are:
/sys/devices/system/cpu/cpufreq/interactive/min_sample_time:
The minimum amount of time to spend at the current frequency before
ramping down. This is to ensure that the governor has seen enough
historic CPU load data to determine the appropriate workload.
/sys/devices/system/cpu/cpufreq/interactive/go_maxspeed_load
The CPU load at which to ramp to max speed.
Signed-off-by: Anson Huang <b20788@freescale.com>
Change a single occurrence of "unlcoked" into "unlocked". Signed-off-by: Bart Van Assche <bvanassche@acm.org> Cc: Darren Hart <dvhltc@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The variables here are really not used uninitialized. kernel/futex.c: In function 'fixup_pi_state_owner.clone.17': kernel/futex.c:1582:6: warning: 'curval' may be used uninitialized in this function kernel/futex.c: In function 'handle_futex_death': kernel/futex.c:2486:6: warning: 'nval' may be used uninitialized in this function kernel/futex.c: In function 'do_futex': kernel/futex.c:863:11: warning: 'curval' may be used uninitialized in this function kernel/futex.c:828:6: note: 'curval' was declared here kernel/futex.c:898:5: warning: 'oldval' may be used uninitialized in this function kernel/futex.c:890:6: note: 'oldval' was declared here Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com> Acked-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>