From 75c43a20b220f885c39ffa7cdbbb1191e257a9a9 Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Fri, 14 Oct 2011 15:46:10 +0200 Subject: oprofile: Remove exit function for timer mode Remove exit functions by moving init/exit code to oprofile's setup/ shutdown functions. Doing so the oprofile module exit code will be easier and less error-prone. Signed-off-by: Robert Richter --- drivers/oprofile/oprof.c | 8 ++------ drivers/oprofile/timer_int.c | 30 +++++++++++++++--------------- 2 files changed, 17 insertions(+), 21 deletions(-) (limited to 'drivers') diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c index f8c752e408a..f7cd06967ae 100644 --- a/drivers/oprofile/oprof.c +++ b/drivers/oprofile/oprof.c @@ -262,9 +262,7 @@ static int __init oprofile_init(void) return 0; /* failed */ - if (timer_mode) - oprofile_timer_exit(); - else + if (!timer_mode) oprofile_arch_exit(); return err; @@ -274,9 +272,7 @@ static int __init oprofile_init(void) static void __exit oprofile_exit(void) { oprofilefs_unregister(); - if (timer_mode) - oprofile_timer_exit(); - else + if (!timer_mode) oprofile_arch_exit(); } diff --git a/drivers/oprofile/timer_int.c b/drivers/oprofile/timer_int.c index 878fba12658..93404f72dfa 100644 --- a/drivers/oprofile/timer_int.c +++ b/drivers/oprofile/timer_int.c @@ -97,24 +97,24 @@ static struct notifier_block __refdata oprofile_cpu_notifier = { .notifier_call = oprofile_cpu_notify, }; -int oprofile_timer_init(struct oprofile_operations *ops) +static int oprofile_hrtimer_setup(void) { - int rc; - - rc = register_hotcpu_notifier(&oprofile_cpu_notifier); - if (rc) - return rc; - ops->create_files = NULL; - ops->setup = NULL; - ops->shutdown = NULL; - ops->start = oprofile_hrtimer_start; - ops->stop = oprofile_hrtimer_stop; - ops->cpu_type = "timer"; - printk(KERN_INFO "oprofile: using timer interrupt.\n"); - return 0; + return register_hotcpu_notifier(&oprofile_cpu_notifier); } -void oprofile_timer_exit(void) +static void oprofile_hrtimer_shutdown(void) { unregister_hotcpu_notifier(&oprofile_cpu_notifier); } + +int oprofile_timer_init(struct oprofile_operations *ops) +{ + ops->create_files = NULL; + ops->setup = oprofile_hrtimer_setup; + ops->shutdown = oprofile_hrtimer_shutdown; + ops->start = oprofile_hrtimer_start; + ops->stop = oprofile_hrtimer_stop; + ops->cpu_type = "timer"; + printk(KERN_INFO "oprofile: using timer interrupt.\n"); + return 0; +} -- cgit v1.2.3-70-g09d2 From dcfce4a095932e6e95d83ad982be3609947963bc Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Tue, 11 Oct 2011 17:11:08 +0200 Subject: oprofile, x86: Reimplement nmi timer mode using perf event The legacy x86 nmi watchdog code was removed with the implementation of the perf based nmi watchdog. This broke Oprofile's nmi timer mode. To run nmi timer mode we relied on a continuous ticking nmi source which the nmi watchdog provided. The nmi tick was no longer available and current watchdog can not be used anymore since it runs with very long periods in the range of seconds. This patch reimplements the nmi timer mode using a perf counter nmi source. V2: * removing pr_info() * fix undefined reference to `__udivdi3' for 32 bit build * fix section mismatch of .cpuinit.data:nmi_timer_cpu_nb * removed nmi timer setup in arch/x86 * implemented function stubs for op_nmi_init/exit() * made code more readable in oprofile_init() V3: * fix architectural initialization in oprofile_init() * fix CONFIG_OPROFILE_NMI_TIMER dependencies Acked-by: Peter Zijlstra Signed-off-by: Robert Richter --- arch/Kconfig | 4 + arch/x86/oprofile/Makefile | 3 +- arch/x86/oprofile/init.c | 30 ++----- arch/x86/oprofile/nmi_timer_int.c | 66 --------------- drivers/oprofile/nmi_timer_int.c | 173 ++++++++++++++++++++++++++++++++++++++ drivers/oprofile/oprof.c | 24 +++--- drivers/oprofile/oprof.h | 9 ++ kernel/events/core.c | 2 + 8 files changed, 208 insertions(+), 103 deletions(-) delete mode 100644 arch/x86/oprofile/nmi_timer_int.c create mode 100644 drivers/oprofile/nmi_timer_int.c (limited to 'drivers') diff --git a/arch/Kconfig b/arch/Kconfig index 4b0669cbb3b..2505740b81d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -30,6 +30,10 @@ config OPROFILE_EVENT_MULTIPLEX config HAVE_OPROFILE bool +config OPROFILE_NMI_TIMER + def_bool y + depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI + config KPROBES bool "Kprobes" depends on MODULES diff --git a/arch/x86/oprofile/Makefile b/arch/x86/oprofile/Makefile index 446902b2a6b..1599f568f0e 100644 --- a/arch/x86/oprofile/Makefile +++ b/arch/x86/oprofile/Makefile @@ -4,9 +4,8 @@ DRIVER_OBJS = $(addprefix ../../../drivers/oprofile/, \ oprof.o cpu_buffer.o buffer_sync.o \ event_buffer.o oprofile_files.o \ oprofilefs.o oprofile_stats.o \ - timer_int.o ) + timer_int.o nmi_timer_int.o ) oprofile-y := $(DRIVER_OBJS) init.o backtrace.o oprofile-$(CONFIG_X86_LOCAL_APIC) += nmi_int.o op_model_amd.o \ op_model_ppro.o op_model_p4.o -oprofile-$(CONFIG_X86_IO_APIC) += nmi_timer_int.o diff --git a/arch/x86/oprofile/init.c b/arch/x86/oprofile/init.c index f148cf65267..9e138d00ad3 100644 --- a/arch/x86/oprofile/init.c +++ b/arch/x86/oprofile/init.c @@ -16,37 +16,23 @@ * with the NMI mode driver. */ +#ifdef CONFIG_X86_LOCAL_APIC extern int op_nmi_init(struct oprofile_operations *ops); -extern int op_nmi_timer_init(struct oprofile_operations *ops); extern void op_nmi_exit(void); -extern void x86_backtrace(struct pt_regs * const regs, unsigned int depth); +#else +static int op_nmi_init(struct oprofile_operations *ops) { return -ENODEV; } +static void op_nmi_exit(void) { } +#endif -static int nmi_timer; +extern void x86_backtrace(struct pt_regs * const regs, unsigned int depth); int __init oprofile_arch_init(struct oprofile_operations *ops) { - int ret; - - ret = -ENODEV; - -#ifdef CONFIG_X86_LOCAL_APIC - ret = op_nmi_init(ops); -#endif - nmi_timer = (ret != 0); -#ifdef CONFIG_X86_IO_APIC - if (nmi_timer) - ret = op_nmi_timer_init(ops); -#endif ops->backtrace = x86_backtrace; - - return ret; + return op_nmi_init(ops); } - void oprofile_arch_exit(void) { -#ifdef CONFIG_X86_LOCAL_APIC - if (!nmi_timer) - op_nmi_exit(); -#endif + op_nmi_exit(); } diff --git a/arch/x86/oprofile/nmi_timer_int.c b/arch/x86/oprofile/nmi_timer_int.c deleted file mode 100644 index 720bf5a53c5..00000000000 --- a/arch/x86/oprofile/nmi_timer_int.c +++ /dev/null @@ -1,66 +0,0 @@ -/** - * @file nmi_timer_int.c - * - * @remark Copyright 2003 OProfile authors - * @remark Read the file COPYING - * - * @author Zwane Mwaikambo - */ - -#include -#include -#include -#include -#include -#include - -#include -#include -#include - -static int profile_timer_exceptions_notify(struct notifier_block *self, - unsigned long val, void *data) -{ - struct die_args *args = (struct die_args *)data; - int ret = NOTIFY_DONE; - - switch (val) { - case DIE_NMI: - oprofile_add_sample(args->regs, 0); - ret = NOTIFY_STOP; - break; - default: - break; - } - return ret; -} - -static struct notifier_block profile_timer_exceptions_nb = { - .notifier_call = profile_timer_exceptions_notify, - .next = NULL, - .priority = NMI_LOW_PRIOR, -}; - -static int timer_start(void) -{ - if (register_die_notifier(&profile_timer_exceptions_nb)) - return 1; - return 0; -} - - -static void timer_stop(void) -{ - unregister_die_notifier(&profile_timer_exceptions_nb); - synchronize_sched(); /* Allow already-started NMIs to complete. */ -} - - -int __init op_nmi_timer_init(struct oprofile_operations *ops) -{ - ops->start = timer_start; - ops->stop = timer_stop; - ops->cpu_type = "timer"; - printk(KERN_INFO "oprofile: using NMI timer interrupt.\n"); - return 0; -} diff --git a/drivers/oprofile/nmi_timer_int.c b/drivers/oprofile/nmi_timer_int.c new file mode 100644 index 00000000000..76f1c9357f3 --- /dev/null +++ b/drivers/oprofile/nmi_timer_int.c @@ -0,0 +1,173 @@ +/** + * @file nmi_timer_int.c + * + * @remark Copyright 2011 Advanced Micro Devices, Inc. + * + * @author Robert Richter + */ + +#include +#include +#include +#include +#include + +#ifdef CONFIG_OPROFILE_NMI_TIMER + +static DEFINE_PER_CPU(struct perf_event *, nmi_timer_events); +static int ctr_running; + +static struct perf_event_attr nmi_timer_attr = { + .type = PERF_TYPE_HARDWARE, + .config = PERF_COUNT_HW_CPU_CYCLES, + .size = sizeof(struct perf_event_attr), + .pinned = 1, + .disabled = 1, +}; + +static void nmi_timer_callback(struct perf_event *event, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + event->hw.interrupts = 0; /* don't throttle interrupts */ + oprofile_add_sample(regs, 0); +} + +static int nmi_timer_start_cpu(int cpu) +{ + struct perf_event *event = per_cpu(nmi_timer_events, cpu); + + if (!event) { + event = perf_event_create_kernel_counter(&nmi_timer_attr, cpu, NULL, + nmi_timer_callback, NULL); + if (IS_ERR(event)) + return PTR_ERR(event); + per_cpu(nmi_timer_events, cpu) = event; + } + + if (event && ctr_running) + perf_event_enable(event); + + return 0; +} + +static void nmi_timer_stop_cpu(int cpu) +{ + struct perf_event *event = per_cpu(nmi_timer_events, cpu); + + if (event && ctr_running) + perf_event_disable(event); +} + +static int nmi_timer_cpu_notifier(struct notifier_block *b, unsigned long action, + void *data) +{ + int cpu = (unsigned long)data; + switch (action) { + case CPU_DOWN_FAILED: + case CPU_ONLINE: + nmi_timer_start_cpu(cpu); + break; + case CPU_DOWN_PREPARE: + nmi_timer_stop_cpu(cpu); + break; + } + return NOTIFY_DONE; +} + +static struct notifier_block nmi_timer_cpu_nb = { + .notifier_call = nmi_timer_cpu_notifier +}; + +static int nmi_timer_start(void) +{ + int cpu; + + get_online_cpus(); + ctr_running = 1; + for_each_online_cpu(cpu) + nmi_timer_start_cpu(cpu); + put_online_cpus(); + + return 0; +} + +static void nmi_timer_stop(void) +{ + int cpu; + + get_online_cpus(); + for_each_online_cpu(cpu) + nmi_timer_stop_cpu(cpu); + ctr_running = 0; + put_online_cpus(); +} + +static void nmi_timer_shutdown(void) +{ + struct perf_event *event; + int cpu; + + get_online_cpus(); + unregister_cpu_notifier(&nmi_timer_cpu_nb); + for_each_possible_cpu(cpu) { + event = per_cpu(nmi_timer_events, cpu); + if (!event) + continue; + perf_event_disable(event); + per_cpu(nmi_timer_events, cpu) = NULL; + perf_event_release_kernel(event); + } + + put_online_cpus(); +} + +static int nmi_timer_setup(void) +{ + int cpu, err; + u64 period; + + /* clock cycles per tick: */ + period = (u64)cpu_khz * 1000; + do_div(period, HZ); + nmi_timer_attr.sample_period = period; + + get_online_cpus(); + err = register_cpu_notifier(&nmi_timer_cpu_nb); + if (err) + goto out; + /* can't attach events to offline cpus: */ + for_each_online_cpu(cpu) { + err = nmi_timer_start_cpu(cpu); + if (err) + break; + } + if (err) + nmi_timer_shutdown(); +out: + put_online_cpus(); + return err; +} + +int __init op_nmi_timer_init(struct oprofile_operations *ops) +{ + int err = 0; + + err = nmi_timer_setup(); + if (err) + return err; + nmi_timer_shutdown(); /* only check, don't alloc */ + + ops->create_files = NULL; + ops->setup = nmi_timer_setup; + ops->shutdown = nmi_timer_shutdown; + ops->start = nmi_timer_start; + ops->stop = nmi_timer_stop; + ops->cpu_type = "timer"; + + printk(KERN_INFO "oprofile: using NMI timer interrupt.\n"); + + return 0; +} + +#endif diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c index f7cd06967ae..ed2c3ec0702 100644 --- a/drivers/oprofile/oprof.c +++ b/drivers/oprofile/oprof.c @@ -246,26 +246,24 @@ static int __init oprofile_init(void) int err; /* always init architecture to setup backtrace support */ + timer_mode = 0; err = oprofile_arch_init(&oprofile_ops); + if (!err) { + if (!timer && !oprofilefs_register()) + return 0; + oprofile_arch_exit(); + } - timer_mode = err || timer; /* fall back to timer mode on errors */ - if (timer_mode) { - if (!err) - oprofile_arch_exit(); + /* setup timer mode: */ + timer_mode = 1; + /* no nmi timer mode if oprofile.timer is set */ + if (timer || op_nmi_timer_init(&oprofile_ops)) { err = oprofile_timer_init(&oprofile_ops); if (err) return err; } - err = oprofilefs_register(); - if (!err) - return 0; - - /* failed */ - if (!timer_mode) - oprofile_arch_exit(); - - return err; + return oprofilefs_register(); } diff --git a/drivers/oprofile/oprof.h b/drivers/oprofile/oprof.h index 177b73de5e5..769fb0fcac4 100644 --- a/drivers/oprofile/oprof.h +++ b/drivers/oprofile/oprof.h @@ -36,6 +36,15 @@ struct dentry; void oprofile_create_files(struct super_block *sb, struct dentry *root); int oprofile_timer_init(struct oprofile_operations *ops); void oprofile_timer_exit(void); +#ifdef CONFIG_OPROFILE_NMI_TIMER +int op_nmi_timer_init(struct oprofile_operations *ops); +#else +static inline int op_nmi_timer_init(struct oprofile_operations *ops) +{ + return -ENODEV; +} +#endif + int oprofile_set_ulong(unsigned long *addr, unsigned long val); int oprofile_set_timeout(unsigned long time); diff --git a/kernel/events/core.c b/kernel/events/core.c index d1a1bee3522..d2e28bdd523 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1322,6 +1322,7 @@ retry: } raw_spin_unlock_irq(&ctx->lock); } +EXPORT_SYMBOL_GPL(perf_event_disable); static void perf_set_shadow_time(struct perf_event *event, struct perf_event_context *ctx, @@ -1806,6 +1807,7 @@ retry: out: raw_spin_unlock_irq(&ctx->lock); } +EXPORT_SYMBOL_GPL(perf_event_enable); int perf_event_refresh(struct perf_event *event, int refresh) { -- cgit v1.2.3-70-g09d2 From f8c852031a383ac260ae37df7ad063d42d0ed271 Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Wed, 7 Dec 2011 11:16:38 +0100 Subject: oprofile: Fix oprofile_timer_exit() breakage Removing remainings of oprofile_timer_exit() completly. Signed-off-by: Robert Richter --- arch/s390/oprofile/init.c | 1 - drivers/oprofile/oprof.h | 1 - 2 files changed, 2 deletions(-) (limited to 'drivers') diff --git a/arch/s390/oprofile/init.c b/arch/s390/oprofile/init.c index 6efc18b5e60..113d7cbbc06 100644 --- a/arch/s390/oprofile/init.c +++ b/arch/s390/oprofile/init.c @@ -171,7 +171,6 @@ static int oprofile_hwsampler_init(struct oprofile_operations *ops) static void oprofile_hwsampler_exit(void) { - oprofile_timer_exit(); hwsampler_shutdown(); } diff --git a/drivers/oprofile/oprof.h b/drivers/oprofile/oprof.h index 769fb0fcac4..d32ef816337 100644 --- a/drivers/oprofile/oprof.h +++ b/drivers/oprofile/oprof.h @@ -35,7 +35,6 @@ struct dentry; void oprofile_create_files(struct super_block *sb, struct dentry *root); int oprofile_timer_init(struct oprofile_operations *ops); -void oprofile_timer_exit(void); #ifdef CONFIG_OPROFILE_NMI_TIMER int op_nmi_timer_init(struct oprofile_operations *ops); #else -- cgit v1.2.3-70-g09d2