* [PATCH] ftrace: Add a C/P state tracer to help power optimization @ 2008-11-23 20:59 Arjan van de Ven 2008-11-23 21:12 ` Frédéric Weisbecker 0 siblings, 1 reply; 5+ messages in thread From: Arjan van de Ven @ 2008-11-23 20:59 UTC (permalink / raw) To: linux-kernel; +Cc: mingo, rostedt >From 9625f8f58b86ddfd49351a252adce2ce85f6070c Mon Sep 17 00:00:00 2001 From: Arjan van de Ven <arjan@linux.intel.com> Date: Fri, 3 Oct 2008 10:18:21 -0700 Subject: [PATCH] ftrace: Add a C/P state tracer to help power optimization This patch adds a C/P-state ftrace plugin that will generate detailed statistics about the C/P-states that are being used, so that we can look at detailed decisions that the C/P-state code is making, rather than the too high level "average" that we have today. An example way of using this is: mount -t debugfs none /sys/kernel/debug echo cstate > /sys/kernel/debug/tracing/current_tracer echo 1 > /sys/kernel/debug/tracing/tracing_enabled sleep 1 echo 0 > /sys/kernel/debug/tracing/tracing_enabled cat /sys/kernel/debug/tracing/trace | perl scripts/trace/cstate.pl > out.svg Impact: New code Impact: Minor additions to existing code Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 4 + arch/x86/kernel/process.c | 16 +++ include/linux/ftrace.h | 29 +++++ kernel/trace/Kconfig | 11 ++ kernel/trace/Makefile | 1 + kernel/trace/trace.h | 7 + kernel/trace/trace_power.c | 184 ++++++++++++++++++++++++++++ 7 files changed, 252 insertions(+), 0 deletions(-) create mode 100644 kernel/trace/trace_power.c diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 8e48c5d..88ea02d 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -33,6 +33,7 @@ #include <linux/cpufreq.h> #include <linux/compiler.h> #include <linux/dmi.h> +#include <linux/ftrace.h> #include <linux/acpi.h> #include <acpi/processor.h> @@ -391,6 +392,7 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, unsigned int next_perf_state = 0; /* Index into perf table */ unsigned int i; int result = 0; + struct power_trace it; dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu); @@ -427,6 +429,8 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, } } + trace_power_mark(&it, POWER_PSTATE, next_perf_state); + switch (data->cpu_feature) { case SYSTEM_INTEL_MSR_CAPABLE: cmd.type = SYSTEM_INTEL_MSR_CAPABLE; diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index c622772..c27af49 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -7,6 +7,7 @@ #include <linux/module.h> #include <linux/pm.h> #include <linux/clockchips.h> +#include <linux/ftrace.h> #include <asm/system.h> unsigned long idle_halt; @@ -100,6 +101,9 @@ static inline int hlt_use_halt(void) void default_idle(void) { if (hlt_use_halt()) { + struct power_trace it; + + trace_power_start(&it, POWER_CSTATE, 1); current_thread_info()->status &= ~TS_POLLING; /* * TS_POLLING-cleared state must be visible before we @@ -112,6 +116,7 @@ void default_idle(void) else local_irq_enable(); current_thread_info()->status |= TS_POLLING; + trace_power_end(&it); } else { local_irq_enable(); /* loop is done by the caller */ @@ -154,24 +159,31 @@ EXPORT_SYMBOL_GPL(cpu_idle_wait); */ void mwait_idle_with_hints(unsigned long ax, unsigned long cx) { + struct power_trace it; + + trace_power_start(&it, POWER_CSTATE, (ax>>4)+1); if (!need_resched()) { __monitor((void *)¤t_thread_info()->flags, 0, 0); smp_mb(); if (!need_resched()) __mwait(ax, cx); } + trace_power_end(&it); } /* Default MONITOR/MWAIT with no hints, used for default C1 state */ static void mwait_idle(void) { + struct power_trace it; if (!need_resched()) { + trace_power_start(&it, POWER_CSTATE, 1); __monitor((void *)¤t_thread_info()->flags, 0, 0); smp_mb(); if (!need_resched()) __sti_mwait(0, 0); else local_irq_enable(); + trace_power_end(&it); } else local_irq_enable(); } @@ -183,9 +195,13 @@ static void mwait_idle(void) */ static void poll_idle(void) { + struct power_trace it; + + trace_power_start(&it, POWER_CSTATE, 0); local_irq_enable(); while (!need_resched()) cpu_relax(); + trace_power_end(&it); } /* diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 703eb53..573095b 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -248,6 +248,35 @@ static inline void start_boot_trace(void) { } static inline void stop_boot_trace(void) { } #endif +enum { + POWER_NONE = 0, + POWER_CSTATE = 1, + POWER_PSTATE = 2, +}; + +struct power_trace { +#ifdef CONFIG_POWER_TRACER + ktime_t stamp; + ktime_t end; + int type; + int state; +#endif +}; + +#ifdef CONFIG_POWER_TRACER +extern void trace_power_start(struct power_trace *it, unsigned int type, + unsigned int state); +extern void trace_power_mark(struct power_trace *it, unsigned int type, + unsigned int state); +extern void trace_power_end(struct power_trace *it); +#else +static inline void trace_power_start(struct power_trace *it, unsigned int type, + unsigned int state) { } +static inline void trace_power_mark(struct power_trace *it, unsigned int type, + unsigned int state) { } +static inline void trace_power_end(struct power_trace *it) { } +#endif + #endif /* _LINUX_FTRACE_H */ diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 33dbefd..f5f2363 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -138,6 +138,17 @@ config BOOT_TRACER selected, because the self-tests are an initcall as well and that would invalidate the boot trace. ) +config POWER_TRACER + bool "Trace power consumption behavior" + depends on DEBUG_KERNEL + depends on X86 + select TRACING + help + This tracer helps developers to analyze and optimize the kernels + power management decisions, specifically the C-state and P-state + behavior. + + config STACK_TRACER bool "Trace max stack" depends on HAVE_FUNCTION_TRACER diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index c8228b1..917b42e 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -24,5 +24,6 @@ obj-$(CONFIG_NOP_TRACER) += trace_nop.o obj-$(CONFIG_STACK_TRACER) += trace_stack.o obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o obj-$(CONFIG_BOOT_TRACER) += trace_boot.o +obj-$(CONFIG_POWER_TRACER) += trace_power.o libftrace-y := ftrace.o diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 8465ad0..77cc01c 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -22,6 +22,7 @@ enum trace_type { TRACE_MMIO_RW, TRACE_MMIO_MAP, TRACE_BOOT, + TRACE_POWER, __TRACE_LAST_TYPE }; @@ -117,6 +118,11 @@ struct trace_boot { struct boot_trace initcall; }; +struct trace_power { + struct trace_entry ent; + struct power_trace state_data; +}; + /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: @@ -219,6 +225,7 @@ extern void __ftrace_bad_type(void); IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ TRACE_MMIO_MAP); \ IF_ASSIGN(var, ent, struct trace_boot, TRACE_BOOT); \ + IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \ __ftrace_bad_type(); \ } while (0) diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c new file mode 100644 index 0000000..db51f3f --- /dev/null +++ b/kernel/trace/trace_power.c @@ -0,0 +1,184 @@ +/* + * ring buffer based C-state tracer + * + * Arjan van de Ven <arjan@linux.intel.com> + * Copyright (C) 2008 Intel Corporation + * + * Much is borrowed from trace_boot.c which is + * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> + * + */ + +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/ftrace.h> +#include <linux/kallsyms.h> +#include <linux/module.h> + +#include "trace.h" + +static struct trace_array *power_trace; +static int __read_mostly trace_power_enabled; + + +static void start_power_trace(void) +{ + trace_power_enabled = 1; +} + +static void stop_power_trace(struct trace_array *tr) +{ + trace_power_enabled = 0; +} + +static void power_trace_init(struct trace_array *tr) +{ + int cpu; + power_trace = tr; + + trace_power_enabled = 1; + + for_each_cpu_mask(cpu, cpu_possible_map) + tracing_reset(tr, cpu); +} + +static void power_trace_ctrl_update(struct trace_array *tr) +{ + if (tr->ctrl) + start_power_trace(); + else + stop_power_trace(tr); +} + +static enum print_line_t power_print_line(struct trace_iterator *iter) +{ + int ret = 0; + struct trace_entry *entry = iter->ent; + struct trace_power *field ; + struct power_trace *it; + struct trace_seq *s = &iter->seq; + struct timespec stamp; + struct timespec duration; + + trace_assign_type(field, entry); + it = &field->state_data; + stamp = ktime_to_timespec(it->stamp); + duration = ktime_to_timespec(ktime_sub(it->end, it->stamp)); + + if (entry->type == TRACE_POWER) { + if (it->type == POWER_CSTATE) + ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n", + stamp.tv_sec, + stamp.tv_nsec, + it->state, iter->cpu, + duration.tv_sec, + duration.tv_nsec); + if (it->type == POWER_PSTATE) + ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n", + stamp.tv_sec, + stamp.tv_nsec, + it->state, iter->cpu); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + return TRACE_TYPE_HANDLED; + } + return TRACE_TYPE_UNHANDLED; +} + +static struct tracer power_tracer __read_mostly = +{ + .name = "power", + .init = power_trace_init, + .reset = stop_power_trace, + .ctrl_update = power_trace_ctrl_update, + .print_line = power_print_line, +}; + +static int init_power_trace(void) +{ + return register_tracer(&power_tracer); +} +device_initcall(init_power_trace); + +void trace_power_start(struct power_trace *it, unsigned int type, + unsigned int level) +{ + if (!trace_power_enabled) + return; + + memset(it, 0, sizeof(struct power_trace)); + it->state = level; + it->type = type; + it->stamp = ktime_get(); +} +EXPORT_SYMBOL_GPL(trace_power_start); + + +void trace_power_end(struct power_trace *it) +{ + struct ring_buffer_event *event; + struct trace_power *entry; + struct trace_array_cpu *data; + unsigned long irq_flags; + struct trace_array *tr = power_trace; + + if (!trace_power_enabled) + return; + + preempt_disable(); + it->end = ktime_get(); + data = tr->data[smp_processor_id()]; + + event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), + &irq_flags); + if (!event) + goto out; + entry = ring_buffer_event_data(event); + tracing_generic_entry_update(&entry->ent, 0, 0); + entry->ent.type = TRACE_POWER; + entry->state_data = *it; + ring_buffer_unlock_commit(tr->buffer, event, irq_flags); + + trace_wake_up(); + + out: + preempt_enable(); +} +EXPORT_SYMBOL_GPL(trace_power_end); + +void trace_power_mark(struct power_trace *it, unsigned int type, + unsigned int level) +{ + struct ring_buffer_event *event; + struct trace_power *entry; + struct trace_array_cpu *data; + unsigned long irq_flags; + struct trace_array *tr = power_trace; + + if (!trace_power_enabled) + return; + + memset(it, 0, sizeof(struct power_trace)); + it->state = level; + it->type = type; + it->stamp = ktime_get(); + preempt_disable(); + it->end = it->stamp; + data = tr->data[smp_processor_id()]; + + event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), + &irq_flags); + if (!event) + goto out; + entry = ring_buffer_event_data(event); + tracing_generic_entry_update(&entry->ent, 0, 0); + entry->ent.type = TRACE_POWER; + entry->state_data = *it; + ring_buffer_unlock_commit(tr->buffer, event, irq_flags); + + trace_wake_up(); + + out: + preempt_enable(); +} +EXPORT_SYMBOL_GPL(trace_power_mark); -- 1.6.0.3 -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ftrace: Add a C/P state tracer to help power optimization 2008-11-23 20:59 [PATCH] ftrace: Add a C/P state tracer to help power optimization Arjan van de Ven @ 2008-11-23 21:12 ` Frédéric Weisbecker 2008-11-24 0:49 ` Arjan van de Ven 0 siblings, 1 reply; 5+ messages in thread From: Frédéric Weisbecker @ 2008-11-23 21:12 UTC (permalink / raw) To: Arjan van de Ven; +Cc: linux-kernel, mingo, rostedt Hi Arjan, 2008/11/23 Arjan van de Ven <arjan@infradead.org>: > +static void power_trace_ctrl_update(struct trace_array *tr) > +{ > + if (tr->ctrl) > + start_power_trace(); > + else > + stop_power_trace(tr); > +} The ctrl_update callback doesn't exist anymore... ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ftrace: Add a C/P state tracer to help power optimization 2008-11-23 21:12 ` Frédéric Weisbecker @ 2008-11-24 0:49 ` Arjan van de Ven 2008-11-25 11:25 ` Frédéric Weisbecker 0 siblings, 1 reply; 5+ messages in thread From: Arjan van de Ven @ 2008-11-24 0:49 UTC (permalink / raw) To: Frédéric Weisbecker; +Cc: linux-kernel, mingo, rostedt On Sun, 23 Nov 2008 22:12:44 +0100 "Frédéric Weisbecker" <fweisbec@gmail.com> wrote: > Hi Arjan, > > 2008/11/23 Arjan van de Ven <arjan@infradead.org>: > > +static void power_trace_ctrl_update(struct trace_array *tr) > > +{ > > + if (tr->ctrl) > > + start_power_trace(); > > + else > > + stop_power_trace(tr); > > +} > > > The ctrl_update callback doesn't exist anymore... the patch was against mainline; below is an updated patch against -tip: >From 679db8acb007a7cb74719c5609307b79b88b18a7 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven <arjan@linux.intel.com> Date: Sun, 23 Nov 2008 16:48:47 -0800 Subject: [PATCH] ftrace: Add a C/P state tracer to help power optimization This patch adds a C/P-state ftrace plugin that will generate detailed statistics about the C/P-states that are being used, so that we can look at detailed decisions that the C/P-state code is making, rather than the too high level "average" that we have today. An example way of using this is: mount -t debugfs none /sys/kernel/debug echo cstate > /sys/kernel/debug/tracing/current_tracer echo 1 > /sys/kernel/debug/tracing/tracing_enabled sleep 1 echo 0 > /sys/kernel/debug/tracing/tracing_enabled cat /sys/kernel/debug/tracing/trace | perl scripts/trace/cstate.pl > out.svg Impact: New code Impact: Minor additions to existing code Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 4 + arch/x86/kernel/process.c | 16 +++ include/linux/ftrace.h | 29 +++++ kernel/trace/Kconfig | 11 ++ kernel/trace/Makefile | 1 + kernel/trace/trace.h | 7 + kernel/trace/trace_power.c | 179 ++++++++++++++++++++++++++++ scripts/trace/power.pl | 108 +++++++++++++++++ 8 files changed, 355 insertions(+), 0 deletions(-) create mode 100644 kernel/trace/trace_power.c create mode 100644 scripts/trace/power.pl diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 8e48c5d..88ea02d 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -33,6 +33,7 @@ #include <linux/cpufreq.h> #include <linux/compiler.h> #include <linux/dmi.h> +#include <linux/ftrace.h> #include <linux/acpi.h> #include <acpi/processor.h> @@ -391,6 +392,7 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, unsigned int next_perf_state = 0; /* Index into perf table */ unsigned int i; int result = 0; + struct power_trace it; dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu); @@ -427,6 +429,8 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, } } + trace_power_mark(&it, POWER_PSTATE, next_perf_state); + switch (data->cpu_feature) { case SYSTEM_INTEL_MSR_CAPABLE: cmd.type = SYSTEM_INTEL_MSR_CAPABLE; diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 8455480..d07993d 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -7,6 +7,7 @@ #include <linux/module.h> #include <linux/pm.h> #include <linux/clockchips.h> +#include <linux/ftrace.h> #include <asm/system.h> #include <asm/apic.h> @@ -101,6 +102,9 @@ static inline int hlt_use_halt(void) void default_idle(void) { if (hlt_use_halt()) { + struct power_trace it; + + trace_power_start(&it, POWER_CSTATE, 1); current_thread_info()->status &= ~TS_POLLING; /* * TS_POLLING-cleared state must be visible before we @@ -113,6 +117,7 @@ void default_idle(void) else local_irq_enable(); current_thread_info()->status |= TS_POLLING; + trace_power_end(&it); } else { local_irq_enable(); /* loop is done by the caller */ @@ -170,24 +175,31 @@ EXPORT_SYMBOL_GPL(cpu_idle_wait); */ void mwait_idle_with_hints(unsigned long ax, unsigned long cx) { + struct power_trace it; + + trace_power_start(&it, POWER_CSTATE, (ax>>4)+1); if (!need_resched()) { __monitor((void *)¤t_thread_info()->flags, 0, 0); smp_mb(); if (!need_resched()) __mwait(ax, cx); } + trace_power_end(&it); } /* Default MONITOR/MWAIT with no hints, used for default C1 state */ static void mwait_idle(void) { + struct power_trace it; if (!need_resched()) { + trace_power_start(&it, POWER_CSTATE, 1); __monitor((void *)¤t_thread_info()->flags, 0, 0); smp_mb(); if (!need_resched()) __sti_mwait(0, 0); else local_irq_enable(); + trace_power_end(&it); } else local_irq_enable(); } @@ -199,9 +211,13 @@ static void mwait_idle(void) */ static void poll_idle(void) { + struct power_trace it; + + trace_power_start(&it, POWER_CSTATE, 0); local_irq_enable(); while (!need_resched()) cpu_relax(); + trace_power_end(&it); } /* diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 7854d87..0df2886 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -311,6 +311,35 @@ ftrace_init_module(struct module *mod, unsigned long *start, unsigned long *end) { } #endif +enum { + POWER_NONE = 0, + POWER_CSTATE = 1, + POWER_PSTATE = 2, +}; + +struct power_trace { +#ifdef CONFIG_POWER_TRACER + ktime_t stamp; + ktime_t end; + int type; + int state; +#endif +}; + +#ifdef CONFIG_POWER_TRACER +extern void trace_power_start(struct power_trace *it, unsigned int type, + unsigned int state); +extern void trace_power_mark(struct power_trace *it, unsigned int type, + unsigned int state); +extern void trace_power_end(struct power_trace *it); +#else +static inline void trace_power_start(struct power_trace *it, unsigned int type, + unsigned int state) { } +static inline void trace_power_mark(struct power_trace *it, unsigned int type, + unsigned int state) { } +static inline void trace_power_end(struct power_trace *it) { } +#endif + /* * Structure that defines a return function trace. diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 9cbf776..eabcd43 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -214,6 +214,17 @@ config BRANCH_TRACER Say N if unsure. +config POWER_TRACER + bool "Trace power consumption behavior" + depends on DEBUG_KERNEL + depends on X86 + select TRACING + help + This tracer helps developers to analyze and optimize the kernels + power management decisions, specifically the C-state and P-state + behavior. + + config STACK_TRACER bool "Trace max stack" depends on HAVE_FUNCTION_TRACER diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 1a8c925..a5ed56b 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -31,5 +31,6 @@ obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o obj-$(CONFIG_BOOT_TRACER) += trace_boot.o obj-$(CONFIG_FUNCTION_RET_TRACER) += trace_functions_return.o obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o +obj-$(CONFIG_POWER_TRACER) += trace_power.o libftrace-y := ftrace.o diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 28c15c2..440faca 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -27,6 +27,7 @@ enum trace_type { TRACE_BOOT_RET, TRACE_FN_RET, TRACE_USER_STACK, + TRACE_POWER, __TRACE_LAST_TYPE }; @@ -153,6 +154,11 @@ struct trace_branch { char correct; }; +struct trace_power { + struct trace_entry ent; + struct power_trace state_data; +}; + /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: @@ -258,6 +264,7 @@ extern void __ftrace_bad_type(void); IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\ IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ IF_ASSIGN(var, ent, struct ftrace_ret_entry, TRACE_FN_RET);\ + IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \ __ftrace_bad_type(); \ } while (0) diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c new file mode 100644 index 0000000..a7172a3 --- /dev/null +++ b/kernel/trace/trace_power.c @@ -0,0 +1,179 @@ +/* + * ring buffer based C-state tracer + * + * Arjan van de Ven <arjan@linux.intel.com> + * Copyright (C) 2008 Intel Corporation + * + * Much is borrowed from trace_boot.c which is + * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> + * + */ + +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/ftrace.h> +#include <linux/kallsyms.h> +#include <linux/module.h> + +#include "trace.h" + +static struct trace_array *power_trace; +static int __read_mostly trace_power_enabled; + + +static void start_power_trace(struct trace_array *tr) +{ + trace_power_enabled = 1; +} + +static void stop_power_trace(struct trace_array *tr) +{ + trace_power_enabled = 0; +} + + +static int power_trace_init(struct trace_array *tr) +{ + int cpu; + power_trace = tr; + + trace_power_enabled = 1; + + for_each_cpu_mask(cpu, cpu_possible_map) + tracing_reset(tr, cpu); + return 0; +} + +static enum print_line_t power_print_line(struct trace_iterator *iter) +{ + int ret = 0; + struct trace_entry *entry = iter->ent; + struct trace_power *field ; + struct power_trace *it; + struct trace_seq *s = &iter->seq; + struct timespec stamp; + struct timespec duration; + + trace_assign_type(field, entry); + it = &field->state_data; + stamp = ktime_to_timespec(it->stamp); + duration = ktime_to_timespec(ktime_sub(it->end, it->stamp)); + + if (entry->type == TRACE_POWER) { + if (it->type == POWER_CSTATE) + ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n", + stamp.tv_sec, + stamp.tv_nsec, + it->state, iter->cpu, + duration.tv_sec, + duration.tv_nsec); + if (it->type == POWER_PSTATE) + ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n", + stamp.tv_sec, + stamp.tv_nsec, + it->state, iter->cpu); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + return TRACE_TYPE_HANDLED; + } + return TRACE_TYPE_UNHANDLED; +} + +static struct tracer power_tracer __read_mostly = +{ + .name = "power", + .init = power_trace_init, + .start = start_power_trace, + .stop = stop_power_trace, + .reset = stop_power_trace, + .print_line = power_print_line, +}; + +static int init_power_trace(void) +{ + return register_tracer(&power_tracer); +} +device_initcall(init_power_trace); + +void trace_power_start(struct power_trace *it, unsigned int type, + unsigned int level) +{ + if (!trace_power_enabled) + return; + + memset(it, 0, sizeof(struct power_trace)); + it->state = level; + it->type = type; + it->stamp = ktime_get(); +} +EXPORT_SYMBOL_GPL(trace_power_start); + + +void trace_power_end(struct power_trace *it) +{ + struct ring_buffer_event *event; + struct trace_power *entry; + struct trace_array_cpu *data; + unsigned long irq_flags; + struct trace_array *tr = power_trace; + + if (!trace_power_enabled) + return; + + preempt_disable(); + it->end = ktime_get(); + data = tr->data[smp_processor_id()]; + + event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), + &irq_flags); + if (!event) + goto out; + entry = ring_buffer_event_data(event); + tracing_generic_entry_update(&entry->ent, 0, 0); + entry->ent.type = TRACE_POWER; + entry->state_data = *it; + ring_buffer_unlock_commit(tr->buffer, event, irq_flags); + + trace_wake_up(); + + out: + preempt_enable(); +} +EXPORT_SYMBOL_GPL(trace_power_end); + +void trace_power_mark(struct power_trace *it, unsigned int type, + unsigned int level) +{ + struct ring_buffer_event *event; + struct trace_power *entry; + struct trace_array_cpu *data; + unsigned long irq_flags; + struct trace_array *tr = power_trace; + + if (!trace_power_enabled) + return; + + memset(it, 0, sizeof(struct power_trace)); + it->state = level; + it->type = type; + it->stamp = ktime_get(); + preempt_disable(); + it->end = it->stamp; + data = tr->data[smp_processor_id()]; + + event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), + &irq_flags); + if (!event) + goto out; + entry = ring_buffer_event_data(event); + tracing_generic_entry_update(&entry->ent, 0, 0); + entry->ent.type = TRACE_POWER; + entry->state_data = *it; + ring_buffer_unlock_commit(tr->buffer, event, irq_flags); + + trace_wake_up(); + + out: + preempt_enable(); +} +EXPORT_SYMBOL_GPL(trace_power_mark); diff --git a/scripts/trace/power.pl b/scripts/trace/power.pl new file mode 100644 index 0000000..4f729b3 --- /dev/null +++ b/scripts/trace/power.pl @@ -0,0 +1,108 @@ +#!/usr/bin/perl + +# Copyright 2008, Intel Corporation +# +# This file is part of the Linux kernel +# +# This program file is free software; you can redistribute it and/or modify it +# under the terms of the GNU General Public License as published by the +# Free Software Foundation; version 2 of the License. +# +# This program is distributed in the hope that it will be useful, but WITHOUT +# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or +# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +# for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program in a file named COPYING; if not, write to the +# Free Software Foundation, Inc., +# 51 Franklin Street, Fifth Floor, +# Boston, MA 02110-1301 USA +# +# Authors: +# Arjan van de Ven <arjan@linux.intel.com> + + +# +# This script turns a cstate ftrace output into a SVG graphic that shows +# historic C-state information +# +# +# cat /sys/kernel/debug/tracing/trace | perl power.pl > out.svg +# + +my @styles; +my $base = 0; + +my @pstate_last; +my @pstate_level; + +$styles[0] = "fill:rgb(0,0,255);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[1] = "fill:rgb(0,255,0);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[2] = "fill:rgb(255,0,20);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[3] = "fill:rgb(255,255,20);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[4] = "fill:rgb(255,0,255);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[5] = "fill:rgb(0,255,255);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[6] = "fill:rgb(0,128,255);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[7] = "fill:rgb(0,255,128);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; +$styles[8] = "fill:rgb(0,25,20);fill-opacity:0.5;stroke-width:1;stroke:rgb(0,0,0)"; + + +print "<?xml version=\"1.0\" standalone=\"no\"?> \n"; +print "<svg width=\"10000\" height=\"100%\" version=\"1.1\" xmlns=\"http://www.w3.org/2000/svg\">\n"; + +my $scale = 30000.0; +while (<>) { + my $line = $_; + if ($line =~ /([0-9\.]+)\] CSTATE: Going to C([0-9]) on cpu ([0-9]+) for ([0-9\.]+)/) { + if ($base == 0) { + $base = $1; + } + my $time = $1 - $base; + $time = $time * $scale; + my $C = $2; + my $cpu = $3; + my $y = 400 * $cpu; + my $duration = $4 * $scale; + my $msec = int($4 * 100000)/100.0; + my $height = $C * 20; + $style = $styles[$C]; + + $y = $y + 140 - $height; + + $x2 = $time + 4; + $y2 = $y + 4; + + + print "<rect x=\"$time\" width=\"$duration\" y=\"$y\" height=\"$height\" style=\"$style\"/>\n"; + print "<text transform=\"translate($x2,$y2) rotate(90)\">C$C $msec</text>\n"; + } + if ($line =~ /([0-9\.]+)\] PSTATE: Going to P([0-9]) on cpu ([0-9]+)/) { + my $time = $1 - $base; + my $state = $2; + my $cpu = $3; + + if (defined($pstate_last[$cpu])) { + my $from = $pstate_last[$cpu]; + my $oldstate = $pstate_state[$cpu]; + my $duration = ($time-$from) * $scale; + + $from = $from * $scale; + my $to = $from + $duration; + my $height = 140 - ($oldstate * (140/8)); + + my $y = 400 * $cpu + 200 + $height; + my $y2 = $y+4; + my $style = $styles[8]; + + print "<rect x=\"$from\" y=\"$y\" width=\"$duration\" height=\"5\" style=\"$style\"/>\n"; + print "<text transform=\"translate($from,$y2)\">P$oldstate (cpu $cpu)</text>\n"; + }; + + $pstate_last[$cpu] = $time; + $pstate_state[$cpu] = $state; + } +} + + +print "</svg>\n"; -- 1.6.0.3 -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ftrace: Add a C/P state tracer to help power optimization 2008-11-24 0:49 ` Arjan van de Ven @ 2008-11-25 11:25 ` Frédéric Weisbecker 2008-11-26 7:35 ` Ingo Molnar 0 siblings, 1 reply; 5+ messages in thread From: Frédéric Weisbecker @ 2008-11-25 11:25 UTC (permalink / raw) To: Arjan van de Ven; +Cc: linux-kernel, mingo, rostedt That looks good... 2008/11/24 Arjan van de Ven <arjan@infradead.org>: > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index 7854d87..0df2886 100644 > --- a/include/linux/ftrace.h > +++ b/include/linux/ftrace.h > @@ -311,6 +311,35 @@ ftrace_init_module(struct module *mod, > unsigned long *start, unsigned long *end) { } > #endif > > +enum { > + POWER_NONE = 0, > + POWER_CSTATE = 1, > + POWER_PSTATE = 2, > +}; > + > +struct power_trace { > +#ifdef CONFIG_POWER_TRACER > + ktime_t stamp; > + ktime_t end; > + int type; > + int state; > +#endif > +}; > + > +#ifdef CONFIG_POWER_TRACER > +extern void trace_power_start(struct power_trace *it, unsigned int type, > + unsigned int state); > +extern void trace_power_mark(struct power_trace *it, unsigned int type, > + unsigned int state); > +extern void trace_power_end(struct power_trace *it); > +#else > +static inline void trace_power_start(struct power_trace *it, unsigned int type, > + unsigned int state) { } > +static inline void trace_power_mark(struct power_trace *it, unsigned int type, > + unsigned int state) { } > +static inline void trace_power_end(struct power_trace *it) { } > +#endif > + Sorry I didn't see it on my last mail. But these headers seem to relate more on "power tracing" rather than "ftrace". Perhaps these would find a better place on trace/power.h I guess that could be done on a delta patch as well.... Just for curiosity, do you have an example of trace and/or graph from this tracer? ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ftrace: Add a C/P state tracer to help power optimization 2008-11-25 11:25 ` Frédéric Weisbecker @ 2008-11-26 7:35 ` Ingo Molnar 0 siblings, 0 replies; 5+ messages in thread From: Ingo Molnar @ 2008-11-26 7:35 UTC (permalink / raw) To: Frédéric Weisbecker; +Cc: Arjan van de Ven, linux-kernel, rostedt * Frédéric Weisbecker <fweisbec@gmail.com> wrote: > That looks good... [...] > > Just for curiosity, do you have an example of trace and/or graph > from this tracer? Output looks like this: # tracer: power # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | [ 54.698035123] CSTATE: Going to C1 on cpu 0 for 0.000022629 [ 54.698059987] CSTATE: Going to C1 on cpu 0 for 0.000074032 [ 54.698191011] CSTATE: Going to C1 on cpu 0 for 0.000134655 [ 54.698327901] CSTATE: Going to C1 on cpu 0 for 0.000276017 [ 54.699178020] CSTATE: Going to C1 on cpu 8 for 0.001454114 [ 54.698138489] CSTATE: Going to C1 on cpu 5 for 0.002507334 [ 54.699079124] CSTATE: Going to C1 on cpu 4 for 0.001611677 [ 54.698605873] CSTATE: Going to C1 on cpu 0 for 0.003998045 [ 54.700276498] CSTATE: Going to C1 on cpu 10 for 0.003994971 [ 54.700636045] CSTATE: Going to C1 on cpu 6 for 0.003993295 [ 54.700637442] CSTATE: Going to C1 on cpu 2 for 0.003993295 [ 54.700634648] CSTATE: Going to C1 on cpu 8 for 0.003998883 Ingo ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2008-11-26 7:36 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2008-11-23 20:59 [PATCH] ftrace: Add a C/P state tracer to help power optimization Arjan van de Ven 2008-11-23 21:12 ` Frédéric Weisbecker 2008-11-24 0:49 ` Arjan van de Ven 2008-11-25 11:25 ` Frédéric Weisbecker 2008-11-26 7:35 ` Ingo Molnar
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