Add a target_load attribute that specifies how aggressively the governor is
to adjust speed to meet the observed load. New target speed is calculated
as the current actual speed (may be higher than target speed on SMP) times
the CPU load (as a fraction) divided by target load (fraction).
cpufreq_frequency_table_target() call use CPUFREQ_RELATION_L to set
the next higher speed rather than next lower speed.
Change-Id: If432451da82f5fed12e15c9421d7d27792376150
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Tracing adds actual speed since this is expected to be key to the
choice of target speed.
Change-Id: Iec936102d0010c4e9dfa143c38a9fd0d551189c3
Signed-off-by: Todd Poynor <toddpoynor@google.com>
The deferrable timer list isn't checked on all idle exits, such as when
hi-res timers expire or ISRs schedule workers. If the idle loop is
exited and it's past time to run the governor load polling timer,
run it immediately. This ensures we handle load spikes caused by actvity
that does not run the normal timer list.
Rename the field that timestamps the "time_in_idle" value to be more
accurate.
Change-Id: Ied590ecbefc83c9a9ec5eb9e31903557f6fa1614
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Avoid wakeups only to handle the governor timer when the system is otherwise
idle.
For platforms where the power cost of remaining in idle at higher CPU
speed may outweigh the cost of a governor wakeup from idle to lower the speed,
set parameter cpufreq_interactive.governidle=1.
Change-Id: Id6c43eb35caecf9b0574fcdd5b769711bc7e6de6
Signed-off-by: LianWei WANG <a22439@motorola.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Helps avoid waking up other CPUs to react to activity on the local CPU.
Change-Id: Ife272aaa7916894a437705d44521b1a1693fbe8e
Signed-off-by: Todd Poynor <toddpoynor@google.com>
When load is below go_hispeed_load, apply the percentage of CPU load to
a max frequency of hispeed_freq instead of the max speed. This avoids
jumping too quickly to hispeed_freq when it is a relatively low
percentage of max speed. This also allows go_hispeed_load to be set to
a high percentage relative to hispeed_freq (as a percentage of max speed,
again useful when hispeed_freq is a low fraction of max speed), to cap
larger loads at hispeed_freq. For example, a load of 60% will typically
move to 60% of hispeed_freq, not 60% of max speed. This causes the
governor to apply two different speed caps, depending on whether load is
below or above go_hispeed_load.
Also fix the type of hispeed_freq, which was u64, to match other
speed data types (and avoid overhead and allow division).
Change-Id: Ie2d0668be161c074aaad77db2037505431457b3a
Signed-off-by: Todd Poynor <toddpoynor@google.com>
First bump speed up to hispeed_freq whenever the current speed is below
hispeed_freq, instead of only when the current speed is the minimum speed.
The previous code made it too difficult to use hispeed_freq as a common
intermediate speed on systems that frequently run at speeds between
minimum and hispeed_freq.
Change-Id: I04ec30bafabf5741e267ff289209b8c2d846824b
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Not useful to have a separate, non-realtime workqueue for speed down
events, avoid priority inversion for speed up events.
Change-Id: Iddcd05545245c847aa1bbe0b8790092914c813d2
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Fix a problem where the hung task mechanism was deeming the interactive
clock boost thread as hung. This was because the thread is created at
module init but never run/woken up until needed. If the governor is not
being used this can be forever. To workaround this explicitly wake up
the thread once all the necessary data structures are initialized. The
latter required some minor code shuffle.
Signed-off-by: Sam Leffler <sleffler@chromium.org>
Change-Id: Ie2c058dd75dcb6460ea10e7ac997e46baf66b1fe
Register an idle notifier only when the governor is active. Also
short-circuit work of idle end if the governor is not enabled.
Signed-off-by: Sam Leffler <sleffler@chromium.org>
Change-Id: I4cae36dd2e7389540d337d74745ffbaa0131870f
Allow speed to drop to flooor frequency but not below, don't pin
to speed at last boost.
Change-Id: I0147c2b7a2e61ba16820605af6baaf09570be787
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Based on previous patches by Tero Kristo <tero.kristo@nokia.com>,
Brian Steuer <bsteuer@codeaurora.org>,
David Ng <dave@codeaurora.org>,
Antti P Miettinen <amiettinen@nvidia.com>, and
Thomas Renninger <trenn@suse.de>
Change-Id: Ic55fedcf6f9310f43a7022fb88e23b0392122769
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Allow speed drop after min_sample_time elapses from last time
the current speed was last re-validated as appropriate for
current load / input boost.
Allow speed bump after min_sample_time (or above_hispeed_delay)
elapses from the time the current speed was originally set.
Change-Id: Ic25687a7a53d25e6544c30c47d7ab6f27a47bee8
Signed-off-by: Todd Poynor <toddpoynor@google.com>
For systems that set a common speed for all CPUs, checking current
speed here could bypass the intermediate hispeed bump decision for
this CPU when another CPU was already at hispeed. This could
result in an overly high setting (for all CPUs) in situations
where all CPUs were about to drop to load levels that map to
hispeed or below.
Change-Id: I186f23dcfc5e2b6336cab8b0327f0c8a9a4482bc
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Apply min_sample_time to the last time the current target speed
was originally requested or re-validated as appropriate for the
current load, not to the time since the current speed was
originally set. Avoids periodic dips in speed during bursty
loads.
Change-Id: I250bda657985de60373f9897cc41f480664d51a1
Signed-off-by: Todd Poynor <toddpoynor@google.com>
If load is above go_hispeed_load, always go to at least hispeed_freq,
even when reducing speed from a higher speed, not just when jumping
up from minimum speed. Avoids running at a lower than intended
speed after a burst of even higher load.
Change-Id: I5b9d2a15ba25ce609b21bac7c724265cf6838dee
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Evaluate spikes in load (below go_hispeed_load) against the maximum
speed supported by the device, not the current speed (which tends to
make it too difficult to raise speed to intermediate levels until
very busy).
Change-Id: Ib937006abf8bedb60891a739acd733e89b732ae0
Signed-off-by: Todd Poynor <toddpoynor@google.com>
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.
Default is 80000 uS.
/sys/devices/system/cpu/cpufreq/interactive/go_maxspeed_load
The CPU load at which to ramp to max speed. Default is 85.
Change-Id: Ib2b362607c62f7c56d35f44a9ef3280f98c17585
Signed-off-by: Mike Chan <mike@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Bug: 3152864
Move the x86_64 idle notifiers originally by Andi Kleen and Venkatesh
Pallipadi to generic.
Change-Id: Idf29cda15be151f494ff245933c12462643388d5
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
get_loadavg doesn't work as intended. According to the comments, it
should be returning an average over a few seconds, but it is actually
reading the instantaneous load. It is almost always returning 0, but
can sometimes, depending on workload, spike very high into the hundreds
even when the average cpu load is under 10%. Disable it for now.
Change-Id: I63ed100af1cf9463549939b8113ed83676db5f86
Signed-off-by: Colin Cross <ccross@android.com>
Decare war on uninterruptible sleep. Add a tracepoint which
walks the kernel stack and dumps the first non-scheduler function
called before the scheduler is invoked.
Change-Id: I19e965d5206329360a92cbfe2afcc8c30f65c229
Signed-off-by: Riley Andrews <riandrews@google.com>
Dumps registers and stacktrace into console-ramoops when called
from a watchdog fiq.
Change-Id: Ib6fab5a52f670db18e64214d5e4890e8292a749c
Signed-off-by: Arve Hjønnevåg <arve@android.com>
This allows the output from the register and stack trace code to be
sent elsewhere.
Change-Id: I41bb0d5a25e1b9ca55feef5dbd675818b2f832d5
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Add fiq_debugger_arm64.c that implements the platform-specific
functions.
Change-Id: I4d8b96777bb8503a93d4eb47bbde8e018740a5bf
Signed-off-by: Colin Cross <ccross@android.com>
Split arm support into a separate .c file that is only built for
CONFIG_ARM.
Change-Id: Iba16f4d51608bf9c3e5c8acefefcd38fead9797c
Signed-off-by: Colin Cross <ccross@android.com>
IRQ mode already passes in a struct pt_regs from get_irq_regs().
FIQ mode passes in something similar but not identical to a
struct pt_regs - FIQ mode stores the spsr of the interrupted mode
in slot 17, while pt_regs expects orig_r0.
Replace the existing mixture of void *regs, unsigned *regs, and
struct pt_regs * const with const struct pt_regs *. Modify
dump_regs not to print the spsr since it won't be there in a
struct pt_regs anyways. Modify dump_allregs to highlight the
mode that was interrupted, making spsr easy to find there.
Change-Id: Ibfe1723d702306c7605fd071737d7be9ee9d8c12
Signed-off-by: Colin Cross <ccross@android.com>
Allow compiling fiq_debugger.c without CONFIG_FIQ_GLUE for
platforms that don't support FIQs.
Change-Id: Iabdfd790d24fa9d47b29d2f850c567af2dcad78f
Signed-off-by: Colin Cross <ccross@android.com>
Rename variables and functions in the global namespace to avoid
future collisions.
Change-Id: Ic23a304b0f794efc94cc6d086fddd63231d99c98
Signed-off-by: Colin Cross <ccross@android.com>
Move fiq_debugger into drivers/staging/android/fiq_debugger/ to
allow for sharing between ARM and ARM64.
Change-Id: I6ca5e8b7e3d000f57da3234260261c5592cef2a8
Signed-off-by: Colin Cross <ccross@android.com>
Avoid conflicts with user mode usage of the same instructions, as with
Clang -ftrapv.
Change-Id: I12d1c6d8f94376bfd2503cb0be843d7e478fb6ea
Signed-off-by: Todd Poynor <toddpoynor@google.com>
debug_console_write calls debug_uart_flush, which will usually wait
until the serial port fifo empties. If another thread is continuously
calling fiq_tty_write, the fifo will constantly be refilled and
debug_uart_flush might never return.
Add a spinlock that is locked in debug_console_write and fiq_tty_write
to ensure they can't run at the same time. This has an extra advantage
of preventing lines from the console and tty from being mixed together.
Also reduce the size returned by fiq_tty_write_room to keep the time
spent with the spinlock held to a reasonable value.
In addition, make sure fiq context can't loop forever by never calling
debug_uart_flush when the console is enabled.
Change-Id: I5712b01f740ca0c84f680d2032c9fa16b7656939
Signed-off-by: Colin Cross <ccross@android.com>
kernel_restart cannot be called from interrupt context. Add support for
commands called from a work function, and implement the "reboot" command
there. Also rename the existing irq-mode command to "reset" and change
it to use machine_restart instead of kernel_restart.
Change-Id: I3c423147c01db03d89e95a5b99096ca89462079f
Signed-off-by: Colin Cross <ccross@android.com>
