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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-17 19:15:14 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-17 19:15:14 -0700
commit77dcfe2b9edc98286cf18e03c243c9b999f955d9 (patch)
tree0ba3c4002b6c26c715bf03fac81d63de13c01d96 /drivers/cpuidle/governors
parentMerge tag 'dmaengine-5.4-rc1' of git://git.infradead.org/users/vkoul/slave-dma (diff)
parentMerge branches 'pm-opp', 'pm-qos', 'acpi-pm', 'pm-domains' and 'pm-tools' (diff)
downloadlinux-dev-77dcfe2b9edc98286cf18e03c243c9b999f955d9.tar.xz
linux-dev-77dcfe2b9edc98286cf18e03c243c9b999f955d9.zip
Merge tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki: "These include a rework of the main suspend-to-idle code flow (related to the handling of spurious wakeups), a switch over of several users of cpufreq notifiers to QoS-based limits, a new devfreq driver for Tegra20, a new cpuidle driver and governor for virtualized guests, an extension of the wakeup sources framework to expose wakeup sources as device objects in sysfs, and more. Specifics: - Rework the main suspend-to-idle control flow to avoid repeating "noirq" device resume and suspend operations in case of spurious wakeups from the ACPI EC and decouple the ACPI EC wakeups support from the LPS0 _DSM support (Rafael Wysocki). - Extend the wakeup sources framework to expose wakeup sources as device objects in sysfs (Tri Vo, Stephen Boyd). - Expose system suspend statistics in sysfs (Kalesh Singh). - Introduce a new haltpoll cpuidle driver and a new matching governor for virtualized guests wanting to do guest-side polling in the idle loop (Marcelo Tosatti, Joao Martins, Wanpeng Li, Stephen Rothwell). - Fix the menu and teo cpuidle governors to allow the scheduler tick to be stopped if PM QoS is used to limit the CPU idle state exit latency in some cases (Rafael Wysocki). - Increase the resolution of the play_idle() argument to microseconds for more fine-grained injection of CPU idle cycles (Daniel Lezcano). - Switch over some users of cpuidle notifiers to the new QoS-based frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events (Viresh Kumar). - Add new cpufreq driver based on nvmem for sun50i (Yangtao Li). - Add support for MT8183 and MT8516 to the mediatek cpufreq driver (Andrew-sh.Cheng, Fabien Parent). - Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson Huang). - Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz). - Update the qcom cpufreq driver (among other things, to make it easier to extend and to use kryo cpufreq for other nvmem-based SoCs) and add qcs404 support to it (Niklas Cassel, Douglas RAILLARD, Sibi Sankar, Sricharan R). - Fix assorted issues and make assorted minor improvements in the cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli, Gustavo Silva, Hariprasad Kelam). - Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd Bergmann). - Add new Exynos PPMU events to devfreq events and extend that mechanism (Lukasz Luba). - Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny). - Improve devfreq documentation and governor code, fix spelling typos in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard Crestez, MyungJoo Ham, Gaël PORTAY). - Add regulators enable and disable to the OPP (operating performance points) framework (Kamil Konieczny). - Update the OPP framework to support multiple opp-suspend properties (Anson Huang). - Fix assorted issues and make assorted minor improvements in the OPP code (Niklas Cassel, Viresh Kumar, Yue Hu). - Clean up the generic power domains (genpd) framework (Ulf Hansson). - Clean up assorted pieces of power management code and documentation (Akinobu Mita, Amit Kucheria, Chuhong Yuan). - Update the pm-graph tool to version 5.5 including multiple fixes and improvements (Todd Brandt). - Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven, Sébastien Szymanski)" * tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (126 commits) cpuidle-haltpoll: Enable kvm guest polling when dedicated physical CPUs are available cpuidle-haltpoll: do not set an owner to allow modunload cpuidle-haltpoll: return -ENODEV on modinit failure cpuidle-haltpoll: set haltpoll as preferred governor cpuidle: allow governor switch on cpuidle_register_driver() PM: runtime: Documentation: add runtime_status ABI document pm-graph: make setVal unbuffered again for python2 and python3 powercap: idle_inject: Use higher resolution for idle injection cpuidle: play_idle: Increase the resolution to usec cpuidle-haltpoll: vcpu hotplug support cpufreq: Add qcs404 to cpufreq-dt-platdev blacklist cpufreq: qcom: Add support for qcs404 on nvmem driver cpufreq: qcom: Refactor the driver to make it easier to extend cpufreq: qcom: Re-organise kryo cpufreq to use it for other nvmem based qcom socs dt-bindings: opp: Add qcom-opp bindings with properties needed for CPR dt-bindings: opp: qcom-nvmem: Support pstates provided by a power domain Documentation: cpufreq: Update policy notifier documentation cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events PM / Domains: Verify PM domain type in dev_pm_genpd_set_performance_state() PM / Domains: Simplify genpd_lookup_dev() ...
Diffstat (limited to 'drivers/cpuidle/governors')
-rw-r--r--drivers/cpuidle/governors/Makefile1
-rw-r--r--drivers/cpuidle/governors/haltpoll.c150
-rw-r--r--drivers/cpuidle/governors/ladder.c21
-rw-r--r--drivers/cpuidle/governors/menu.c21
-rw-r--r--drivers/cpuidle/governors/teo.c60
5 files changed, 194 insertions, 59 deletions
diff --git a/drivers/cpuidle/governors/Makefile b/drivers/cpuidle/governors/Makefile
index 42f44cc610dd..63abb5393a4d 100644
--- a/drivers/cpuidle/governors/Makefile
+++ b/drivers/cpuidle/governors/Makefile
@@ -6,3 +6,4 @@
obj-$(CONFIG_CPU_IDLE_GOV_LADDER) += ladder.o
obj-$(CONFIG_CPU_IDLE_GOV_MENU) += menu.o
obj-$(CONFIG_CPU_IDLE_GOV_TEO) += teo.o
+obj-$(CONFIG_CPU_IDLE_GOV_HALTPOLL) += haltpoll.o
diff --git a/drivers/cpuidle/governors/haltpoll.c b/drivers/cpuidle/governors/haltpoll.c
new file mode 100644
index 000000000000..7a703d2e0064
--- /dev/null
+++ b/drivers/cpuidle/governors/haltpoll.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * haltpoll.c - haltpoll idle governor
+ *
+ * Copyright 2019 Red Hat, Inc. and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Authors: Marcelo Tosatti <mtosatti@redhat.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/cpuidle.h>
+#include <linux/time.h>
+#include <linux/ktime.h>
+#include <linux/hrtimer.h>
+#include <linux/tick.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/kvm_para.h>
+
+static unsigned int guest_halt_poll_ns __read_mostly = 200000;
+module_param(guest_halt_poll_ns, uint, 0644);
+
+/* division factor to shrink halt_poll_ns */
+static unsigned int guest_halt_poll_shrink __read_mostly = 2;
+module_param(guest_halt_poll_shrink, uint, 0644);
+
+/* multiplication factor to grow per-cpu poll_limit_ns */
+static unsigned int guest_halt_poll_grow __read_mostly = 2;
+module_param(guest_halt_poll_grow, uint, 0644);
+
+/* value in us to start growing per-cpu halt_poll_ns */
+static unsigned int guest_halt_poll_grow_start __read_mostly = 50000;
+module_param(guest_halt_poll_grow_start, uint, 0644);
+
+/* allow shrinking guest halt poll */
+static bool guest_halt_poll_allow_shrink __read_mostly = true;
+module_param(guest_halt_poll_allow_shrink, bool, 0644);
+
+/**
+ * haltpoll_select - selects the next idle state to enter
+ * @drv: cpuidle driver containing state data
+ * @dev: the CPU
+ * @stop_tick: indication on whether or not to stop the tick
+ */
+static int haltpoll_select(struct cpuidle_driver *drv,
+ struct cpuidle_device *dev,
+ bool *stop_tick)
+{
+ int latency_req = cpuidle_governor_latency_req(dev->cpu);
+
+ if (!drv->state_count || latency_req == 0) {
+ *stop_tick = false;
+ return 0;
+ }
+
+ if (dev->poll_limit_ns == 0)
+ return 1;
+
+ /* Last state was poll? */
+ if (dev->last_state_idx == 0) {
+ /* Halt if no event occurred on poll window */
+ if (dev->poll_time_limit == true)
+ return 1;
+
+ *stop_tick = false;
+ /* Otherwise, poll again */
+ return 0;
+ }
+
+ *stop_tick = false;
+ /* Last state was halt: poll */
+ return 0;
+}
+
+static void adjust_poll_limit(struct cpuidle_device *dev, unsigned int block_us)
+{
+ unsigned int val;
+ u64 block_ns = block_us*NSEC_PER_USEC;
+
+ /* Grow cpu_halt_poll_us if
+ * cpu_halt_poll_us < block_ns < guest_halt_poll_us
+ */
+ if (block_ns > dev->poll_limit_ns && block_ns <= guest_halt_poll_ns) {
+ val = dev->poll_limit_ns * guest_halt_poll_grow;
+
+ if (val < guest_halt_poll_grow_start)
+ val = guest_halt_poll_grow_start;
+ if (val > guest_halt_poll_ns)
+ val = guest_halt_poll_ns;
+
+ dev->poll_limit_ns = val;
+ } else if (block_ns > guest_halt_poll_ns &&
+ guest_halt_poll_allow_shrink) {
+ unsigned int shrink = guest_halt_poll_shrink;
+
+ val = dev->poll_limit_ns;
+ if (shrink == 0)
+ val = 0;
+ else
+ val /= shrink;
+ dev->poll_limit_ns = val;
+ }
+}
+
+/**
+ * haltpoll_reflect - update variables and update poll time
+ * @dev: the CPU
+ * @index: the index of actual entered state
+ */
+static void haltpoll_reflect(struct cpuidle_device *dev, int index)
+{
+ dev->last_state_idx = index;
+
+ if (index != 0)
+ adjust_poll_limit(dev, dev->last_residency);
+}
+
+/**
+ * haltpoll_enable_device - scans a CPU's states and does setup
+ * @drv: cpuidle driver
+ * @dev: the CPU
+ */
+static int haltpoll_enable_device(struct cpuidle_driver *drv,
+ struct cpuidle_device *dev)
+{
+ dev->poll_limit_ns = 0;
+
+ return 0;
+}
+
+static struct cpuidle_governor haltpoll_governor = {
+ .name = "haltpoll",
+ .rating = 9,
+ .enable = haltpoll_enable_device,
+ .select = haltpoll_select,
+ .reflect = haltpoll_reflect,
+};
+
+static int __init init_haltpoll(void)
+{
+ if (kvm_para_available())
+ return cpuidle_register_governor(&haltpoll_governor);
+
+ return 0;
+}
+
+postcore_initcall(init_haltpoll);
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index f0dddc66af26..428eeb832fe7 100644
--- a/drivers/cpuidle/governors/ladder.c
+++ b/drivers/cpuidle/governors/ladder.c
@@ -38,7 +38,6 @@ struct ladder_device_state {
struct ladder_device {
struct ladder_device_state states[CPUIDLE_STATE_MAX];
- int last_state_idx;
};
static DEFINE_PER_CPU(struct ladder_device, ladder_devices);
@@ -49,12 +48,13 @@ static DEFINE_PER_CPU(struct ladder_device, ladder_devices);
* @old_idx: the current state index
* @new_idx: the new target state index
*/
-static inline void ladder_do_selection(struct ladder_device *ldev,
+static inline void ladder_do_selection(struct cpuidle_device *dev,
+ struct ladder_device *ldev,
int old_idx, int new_idx)
{
ldev->states[old_idx].stats.promotion_count = 0;
ldev->states[old_idx].stats.demotion_count = 0;
- ldev->last_state_idx = new_idx;
+ dev->last_state_idx = new_idx;
}
/**
@@ -68,13 +68,13 @@ static int ladder_select_state(struct cpuidle_driver *drv,
{
struct ladder_device *ldev = this_cpu_ptr(&ladder_devices);
struct ladder_device_state *last_state;
- int last_residency, last_idx = ldev->last_state_idx;
+ int last_residency, last_idx = dev->last_state_idx;
int first_idx = drv->states[0].flags & CPUIDLE_FLAG_POLLING ? 1 : 0;
int latency_req = cpuidle_governor_latency_req(dev->cpu);
/* Special case when user has set very strict latency requirement */
if (unlikely(latency_req == 0)) {
- ladder_do_selection(ldev, last_idx, 0);
+ ladder_do_selection(dev, ldev, last_idx, 0);
return 0;
}
@@ -91,7 +91,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
last_state->stats.promotion_count++;
last_state->stats.demotion_count = 0;
if (last_state->stats.promotion_count >= last_state->threshold.promotion_count) {
- ladder_do_selection(ldev, last_idx, last_idx + 1);
+ ladder_do_selection(dev, ldev, last_idx, last_idx + 1);
return last_idx + 1;
}
}
@@ -107,7 +107,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
if (drv->states[i].exit_latency <= latency_req)
break;
}
- ladder_do_selection(ldev, last_idx, i);
+ ladder_do_selection(dev, ldev, last_idx, i);
return i;
}
@@ -116,7 +116,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
last_state->stats.demotion_count++;
last_state->stats.promotion_count = 0;
if (last_state->stats.demotion_count >= last_state->threshold.demotion_count) {
- ladder_do_selection(ldev, last_idx, last_idx - 1);
+ ladder_do_selection(dev, ldev, last_idx, last_idx - 1);
return last_idx - 1;
}
}
@@ -139,7 +139,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv,
struct ladder_device_state *lstate;
struct cpuidle_state *state;
- ldev->last_state_idx = first_idx;
+ dev->last_state_idx = first_idx;
for (i = first_idx; i < drv->state_count; i++) {
state = &drv->states[i];
@@ -167,9 +167,8 @@ static int ladder_enable_device(struct cpuidle_driver *drv,
*/
static void ladder_reflect(struct cpuidle_device *dev, int index)
{
- struct ladder_device *ldev = this_cpu_ptr(&ladder_devices);
if (index > 0)
- ldev->last_state_idx = index;
+ dev->last_state_idx = index;
}
static struct cpuidle_governor ladder_governor = {
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index e9a28c7846d6..e5a5d0c8d66b 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -117,7 +117,6 @@
*/
struct menu_device {
- int last_state_idx;
int needs_update;
int tick_wakeup;
@@ -302,9 +301,10 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
!drv->states[0].disabled && !dev->states_usage[0].disable)) {
/*
* In this case state[0] will be used no matter what, so return
- * it right away and keep the tick running.
+ * it right away and keep the tick running if state[0] is a
+ * polling one.
*/
- *stop_tick = false;
+ *stop_tick = !(drv->states[0].flags & CPUIDLE_FLAG_POLLING);
return 0;
}
@@ -395,16 +395,9 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
return idx;
}
- if (s->exit_latency > latency_req) {
- /*
- * If we break out of the loop for latency reasons, use
- * the target residency of the selected state as the
- * expected idle duration so that the tick is retained
- * as long as that target residency is low enough.
- */
- predicted_us = drv->states[idx].target_residency;
+ if (s->exit_latency > latency_req)
break;
- }
+
idx = i;
}
@@ -455,7 +448,7 @@ static void menu_reflect(struct cpuidle_device *dev, int index)
{
struct menu_device *data = this_cpu_ptr(&menu_devices);
- data->last_state_idx = index;
+ dev->last_state_idx = index;
data->needs_update = 1;
data->tick_wakeup = tick_nohz_idle_got_tick();
}
@@ -468,7 +461,7 @@ static void menu_reflect(struct cpuidle_device *dev, int index)
static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
{
struct menu_device *data = this_cpu_ptr(&menu_devices);
- int last_idx = data->last_state_idx;
+ int last_idx = dev->last_state_idx;
struct cpuidle_state *target = &drv->states[last_idx];
unsigned int measured_us;
unsigned int new_factor;
diff --git a/drivers/cpuidle/governors/teo.c b/drivers/cpuidle/governors/teo.c
index 7d05efdbd3c6..b5a0e498f798 100644
--- a/drivers/cpuidle/governors/teo.c
+++ b/drivers/cpuidle/governors/teo.c
@@ -96,7 +96,6 @@ struct teo_idle_state {
* @time_span_ns: Time between idle state selection and post-wakeup update.
* @sleep_length_ns: Time till the closest timer event (at the selection time).
* @states: Idle states data corresponding to this CPU.
- * @last_state: Idle state entered by the CPU last time.
* @interval_idx: Index of the most recent saved idle interval.
* @intervals: Saved idle duration values.
*/
@@ -104,7 +103,6 @@ struct teo_cpu {
u64 time_span_ns;
u64 sleep_length_ns;
struct teo_idle_state states[CPUIDLE_STATE_MAX];
- int last_state;
int interval_idx;
unsigned int intervals[INTERVALS];
};
@@ -125,12 +123,15 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
if (cpu_data->time_span_ns >= cpu_data->sleep_length_ns) {
/*
- * One of the safety nets has triggered or this was a timer
- * wakeup (or equivalent).
+ * One of the safety nets has triggered or the wakeup was close
+ * enough to the closest timer event expected at the idle state
+ * selection time to be discarded.
*/
- measured_us = sleep_length_us;
+ measured_us = UINT_MAX;
} else {
- unsigned int lat = drv->states[cpu_data->last_state].exit_latency;
+ unsigned int lat;
+
+ lat = drv->states[dev->last_state_idx].exit_latency;
measured_us = ktime_to_us(cpu_data->time_span_ns);
/*
@@ -189,15 +190,6 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
}
/*
- * If the total time span between idle state selection and the "reflect"
- * callback is greater than or equal to the sleep length determined at
- * the idle state selection time, the wakeup is likely to be due to a
- * timer event.
- */
- if (cpu_data->time_span_ns >= cpu_data->sleep_length_ns)
- measured_us = UINT_MAX;
-
- /*
* Save idle duration values corresponding to non-timer wakeups for
* pattern detection.
*/
@@ -242,12 +234,12 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
int latency_req = cpuidle_governor_latency_req(dev->cpu);
unsigned int duration_us, count;
- int max_early_idx, idx, i;
+ int max_early_idx, constraint_idx, idx, i;
ktime_t delta_tick;
- if (cpu_data->last_state >= 0) {
+ if (dev->last_state_idx >= 0) {
teo_update(drv, dev);
- cpu_data->last_state = -1;
+ dev->last_state_idx = -1;
}
cpu_data->time_span_ns = local_clock();
@@ -257,6 +249,7 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
count = 0;
max_early_idx = -1;
+ constraint_idx = drv->state_count;
idx = -1;
for (i = 0; i < drv->state_count; i++) {
@@ -286,16 +279,8 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
if (s->target_residency > duration_us)
break;
- if (s->exit_latency > latency_req) {
- /*
- * If we break out of the loop for latency reasons, use
- * the target residency of the selected state as the
- * expected idle duration to avoid stopping the tick
- * as long as that target residency is low enough.
- */
- duration_us = drv->states[idx].target_residency;
- goto refine;
- }
+ if (s->exit_latency > latency_req && constraint_idx > i)
+ constraint_idx = i;
idx = i;
@@ -321,7 +306,13 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
duration_us = drv->states[idx].target_residency;
}
-refine:
+ /*
+ * If there is a latency constraint, it may be necessary to use a
+ * shallower idle state than the one selected so far.
+ */
+ if (constraint_idx < idx)
+ idx = constraint_idx;
+
if (idx < 0) {
idx = 0; /* No states enabled. Must use 0. */
} else if (idx > 0) {
@@ -331,13 +322,12 @@ refine:
/*
* Count and sum the most recent idle duration values less than
- * the target residency of the state selected so far, find the
- * max.
+ * the current expected idle duration value.
*/
for (i = 0; i < INTERVALS; i++) {
unsigned int val = cpu_data->intervals[i];
- if (val >= drv->states[idx].target_residency)
+ if (val >= duration_us)
continue;
count++;
@@ -356,8 +346,10 @@ refine:
* would be too shallow.
*/
if (!(tick_nohz_tick_stopped() && avg_us < TICK_USEC)) {
- idx = teo_find_shallower_state(drv, dev, idx, avg_us);
duration_us = avg_us;
+ if (drv->states[idx].target_residency > avg_us)
+ idx = teo_find_shallower_state(drv, dev,
+ idx, avg_us);
}
}
}
@@ -394,7 +386,7 @@ static void teo_reflect(struct cpuidle_device *dev, int state)
{
struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
- cpu_data->last_state = state;
+ dev->last_state_idx = state;
/*
* If the wakeup was not "natural", but triggered by one of the safety
* nets, assume that the CPU might have been idle for the entire sleep