From 58687acba59266735adb8ccd9b5b9aa2c7cd205b Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Fri, 7 May 2010 17:11:44 -0400 Subject: lockup_detector: Combine nmi_watchdog and softlockup detector The new nmi_watchdog (which uses the perf event subsystem) is very similar in structure to the softlockup detector. Using Ingo's suggestion, I combined the two functionalities into one file: kernel/watchdog.c. Now both the nmi_watchdog (or hardlockup detector) and softlockup detector sit on top of the perf event subsystem, which is run every 60 seconds or so to see if there are any lockups. To detect hardlockups, cpus not responding to interrupts, I implemented an hrtimer that runs 5 times for every perf event overflow event. If that stops counting on a cpu, then the cpu is most likely in trouble. To detect softlockups, tasks not yielding to the scheduler, I used the previous kthread idea that now gets kicked every time the hrtimer fires. If the kthread isn't being scheduled neither is anyone else and the warning is printed to the console. I tested this on x86_64 and both the softlockup and hardlockup paths work. V2: - cleaned up the Kconfig and softlockup combination - surrounded hardlockup cases with #ifdef CONFIG_PERF_EVENTS_NMI - seperated out the softlockup case from perf event subsystem - re-arranged the enabling/disabling nmi watchdog from proc space - added cpumasks for hardlockup failure cases - removed fallback to soft events if no PMU exists for hard events V3: - comment cleanups - drop support for older softlockup code - per_cpu cleanups - completely remove software clock base hardlockup detector - use per_cpu masking on hard/soft lockup detection - #ifdef cleanups - rename config option NMI_WATCHDOG to LOCKUP_DETECTOR - documentation additions V4: - documentation fixes - convert per_cpu to __get_cpu_var - powerpc compile fixes V5: - split apart warn flags for hard and soft lockups TODO: - figure out how to make an arch-agnostic clock2cycles call (if possible) to feed into perf events as a sample period [fweisbec: merged conflict patch] Signed-off-by: Don Zickus Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Cyrill Gorcunov Cc: Eric Paris Cc: Randy Dunlap LKML-Reference: <1273266711-18706-2-git-send-email-dzickus@redhat.com> Signed-off-by: Frederic Weisbecker --- include/linux/sched.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index dad7f668ebf..37efe8fa530 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -346,6 +346,12 @@ extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, size_t *lenp, loff_t *ppos); #endif +#ifdef CONFIG_LOCKUP_DETECTOR +extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, + void __user *buffer, + size_t *lenp, loff_t *ppos); +#endif + /* Attach to any functions which should be ignored in wchan output. */ #define __sched __attribute__((__section__(".sched.text"))) -- cgit v1.2.3 From 332fbdbca3f7716c5620970755ae054d213bcc4e Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Fri, 7 May 2010 17:11:45 -0400 Subject: lockup_detector: Touch_softlockup cleanups and softlockup_tick removal Just some code cleanup to make touch_softlockup clearer and remove the softlockup_tick function as it is no longer needed. Also remove the /proc softlockup_thres call as it has been changed to watchdog_thres. Signed-off-by: Don Zickus Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Cyrill Gorcunov Cc: Eric Paris Cc: Randy Dunlap LKML-Reference: <1273266711-18706-3-git-send-email-dzickus@redhat.com> Signed-off-by: Frederic Weisbecker --- include/linux/sched.h | 16 +++------------- kernel/sysctl.c | 9 --------- kernel/timer.c | 1 - kernel/watchdog.c | 35 +++-------------------------------- 4 files changed, 6 insertions(+), 55 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 37efe8fa530..33f9b2ad0bb 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -312,19 +312,15 @@ extern void scheduler_tick(void); extern void sched_show_task(struct task_struct *p); #ifdef CONFIG_DETECT_SOFTLOCKUP -extern void softlockup_tick(void); extern void touch_softlockup_watchdog(void); extern void touch_softlockup_watchdog_sync(void); extern void touch_all_softlockup_watchdogs(void); -extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos); +extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, + void __user *buffer, + size_t *lenp, loff_t *ppos); extern unsigned int softlockup_panic; extern int softlockup_thresh; #else -static inline void softlockup_tick(void) -{ -} static inline void touch_softlockup_watchdog(void) { } @@ -346,12 +342,6 @@ extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, size_t *lenp, loff_t *ppos); #endif -#ifdef CONFIG_LOCKUP_DETECTOR -extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos); -#endif - /* Attach to any functions which should be ignored in wchan output. */ #define __sched __attribute__((__section__(".sched.text"))) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0f9adda85f9..999bc3fccf4 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -817,15 +817,6 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one, }, - { - .procname = "softlockup_thresh", - .data = &softlockup_thresh, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dosoftlockup_thresh, - .extra1 = &neg_one, - .extra2 = &sixty, - }, #endif #ifdef CONFIG_DETECT_HUNG_TASK { diff --git a/kernel/timer.c b/kernel/timer.c index aeb6a54f277..e8de5eb07a0 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1225,7 +1225,6 @@ void run_local_timers(void) { hrtimer_run_queues(); raise_softirq(TIMER_SOFTIRQ); - softlockup_tick(); } /* diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 6b7fad8497a..f1541b7e324 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -119,13 +119,12 @@ static void __touch_watchdog(void) __get_cpu_var(watchdog_touch_ts) = get_timestamp(this_cpu); } -void touch_watchdog(void) +void touch_softlockup_watchdog(void) { __get_cpu_var(watchdog_touch_ts) = 0; } -EXPORT_SYMBOL(touch_watchdog); -void touch_all_watchdog(void) +void touch_all_softlockup_watchdogs(void) { int cpu; @@ -140,35 +139,16 @@ void touch_all_watchdog(void) void touch_nmi_watchdog(void) { - touch_watchdog(); + touch_softlockup_watchdog(); } EXPORT_SYMBOL(touch_nmi_watchdog); -void touch_all_nmi_watchdog(void) -{ - touch_all_watchdog(); -} - -void touch_softlockup_watchdog(void) -{ - touch_watchdog(); -} - -void touch_all_softlockup_watchdogs(void) -{ - touch_all_watchdog(); -} - void touch_softlockup_watchdog_sync(void) { __raw_get_cpu_var(softlockup_touch_sync) = true; __raw_get_cpu_var(watchdog_touch_ts) = 0; } -void softlockup_tick(void) -{ -} - #ifdef CONFIG_PERF_EVENTS_NMI /* watchdog detector functions */ static int is_hardlockup(int cpu) @@ -522,15 +502,6 @@ int proc_dowatchdog_thresh(struct ctl_table *table, int write, { return proc_dointvec_minmax(table, write, buffer, lenp, ppos); } - -/* stub functions */ -int proc_dosoftlockup_thresh(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos) -{ - return proc_dowatchdog_thresh(table, write, buffer, lenp, ppos); -} -/* end of stub functions */ #endif /* CONFIG_SYSCTL */ -- cgit v1.2.3 From 19cc36c0f0457e5c6629ec24036fbbe8255c88ec Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 13 May 2010 02:30:49 +0200 Subject: lockup_detector: Fix forgotten config conversion Fix forgotten CONFIG_DETECT_SOFTLOCKUP -> CONFIG_LOCKUP_DETECTOR in sched.h Fixes: arch/x86/built-in.o: In function `touch_nmi_watchdog': (.text+0x1bd59): undefined reference to `touch_softlockup_watchdog' kernel/built-in.o: In function `show_state_filter': (.text+0x10d01): undefined reference to `touch_all_softlockup_watchdogs' kernel/built-in.o: In function `sched_clock_idle_wakeup_event': (.text+0x362f9): undefined reference to `touch_softlockup_watchdog' kernel/built-in.o: In function `timekeeping_resume': timekeeping.c:(.text+0x38757): undefined reference to `touch_softlockup_watchdog' kernel/built-in.o: In function `tick_nohz_handler': tick-sched.c:(.text+0x3e5b9): undefined reference to `touch_softlockup_watchdog' kernel/built-in.o: In function `tick_sched_timer': tick-sched.c:(.text+0x3e671): undefined reference to `touch_softlockup_watchdog' kernel/built-in.o: In function `tick_check_idle': (.text+0x3e90b): undefined reference to `touch_softlockup_watchdog' Signed-off-by: Frederic Weisbecker Cc: Don Zickus Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Cyrill Gorcunov Cc: Eric Paris Cc: Randy Dunlap --- include/linux/sched.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 33f9b2ad0bb..3958e0cd24f 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -311,7 +311,7 @@ extern void scheduler_tick(void); extern void sched_show_task(struct task_struct *p); -#ifdef CONFIG_DETECT_SOFTLOCKUP +#ifdef CONFIG_LOCKUP_DETECTOR extern void touch_softlockup_watchdog(void); extern void touch_softlockup_watchdog_sync(void); extern void touch_all_softlockup_watchdogs(void); -- cgit v1.2.3 From eb7beb5c09af75494234ea6acd09d0a647cf7338 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 16 Jul 2010 00:50:03 +0200 Subject: tracing: Remove special traces Special traces type was only used by sysprof. Lets remove it now that sysprof ftrace plugin has been dropped. Signed-off-by: Frederic Weisbecker Acked-by: Soeren Sandmann Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Steven Rostedt Cc: Li Zefan --- include/linux/kernel.h | 5 ---- include/linux/sched.h | 12 -------- kernel/trace/trace.c | 55 ------------------------------------ kernel/trace/trace.h | 7 ----- kernel/trace/trace_entries.h | 17 ----------- kernel/trace/trace_output.c | 66 ------------------------------------------- kernel/trace/trace_selftest.c | 1 - 7 files changed, 163 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 8317ec4b9f3..adee958b598 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -508,9 +508,6 @@ extern void tracing_start(void); extern void tracing_stop(void); extern void ftrace_off_permanent(void); -extern void -ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3); - static inline void __attribute__ ((format (printf, 1, 2))) ____trace_printk_check_format(const char *fmt, ...) { @@ -586,8 +583,6 @@ __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); #else -static inline void -ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } static inline int trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); diff --git a/include/linux/sched.h b/include/linux/sched.h index 747fcaedddb..f751ea9dcb7 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2434,18 +2434,6 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) #endif /* CONFIG_SMP */ -#ifdef CONFIG_TRACING -extern void -__trace_special(void *__tr, void *__data, - unsigned long arg1, unsigned long arg2, unsigned long arg3); -#else -static inline void -__trace_special(void *__tr, void *__data, - unsigned long arg1, unsigned long arg2, unsigned long arg3) -{ -} -#endif - extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); extern long sched_getaffinity(pid_t pid, struct cpumask *mask); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 78a49e67f7d..d9a4aa02c38 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1331,61 +1331,6 @@ static void __trace_userstack(struct trace_array *tr, unsigned long flags) #endif /* CONFIG_STACKTRACE */ -static void -ftrace_trace_special(void *__tr, - unsigned long arg1, unsigned long arg2, unsigned long arg3, - int pc) -{ - struct ftrace_event_call *call = &event_special; - struct ring_buffer_event *event; - struct trace_array *tr = __tr; - struct ring_buffer *buffer = tr->buffer; - struct special_entry *entry; - - event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, - sizeof(*entry), 0, pc); - if (!event) - return; - entry = ring_buffer_event_data(event); - entry->arg1 = arg1; - entry->arg2 = arg2; - entry->arg3 = arg3; - - if (!filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, 0, pc); -} - -void -__trace_special(void *__tr, void *__data, - unsigned long arg1, unsigned long arg2, unsigned long arg3) -{ - ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); -} - -void -ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) -{ - struct trace_array *tr = &global_trace; - struct trace_array_cpu *data; - unsigned long flags; - int cpu; - int pc; - - if (tracing_disabled) - return; - - pc = preempt_count(); - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - - if (likely(atomic_inc_return(&data->disabled) == 1)) - ftrace_trace_special(tr, arg1, arg2, arg3, pc); - - atomic_dec(&data->disabled); - local_irq_restore(flags); -} - /** * trace_vbprintk - write binary msg to tracing buffer * diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 2114b4c1150..638a5887e2e 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -22,7 +22,6 @@ enum trace_type { TRACE_STACK, TRACE_PRINT, TRACE_BPRINT, - TRACE_SPECIAL, TRACE_MMIO_RW, TRACE_MMIO_MAP, TRACE_BRANCH, @@ -189,7 +188,6 @@ extern void __ftrace_bad_type(void); IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ - IF_ASSIGN(var, ent, struct special_entry, 0); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ TRACE_MMIO_RW); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ @@ -332,11 +330,6 @@ void tracing_sched_wakeup_trace(struct trace_array *tr, struct task_struct *wakee, struct task_struct *cur, unsigned long flags, int pc); -void trace_special(struct trace_array *tr, - struct trace_array_cpu *data, - unsigned long arg1, - unsigned long arg2, - unsigned long arg3, int pc); void trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h index 84128371f25..e3dfecaf13e 100644 --- a/kernel/trace/trace_entries.h +++ b/kernel/trace/trace_entries.h @@ -150,23 +150,6 @@ FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry, ) ); -/* - * Special (free-form) trace entry: - */ -FTRACE_ENTRY(special, special_entry, - - TRACE_SPECIAL, - - F_STRUCT( - __field( unsigned long, arg1 ) - __field( unsigned long, arg2 ) - __field( unsigned long, arg3 ) - ), - - F_printk("(%08lx) (%08lx) (%08lx)", - __entry->arg1, __entry->arg2, __entry->arg3) -); - /* * Stack-trace entry: */ diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 57c1b459647..a46197b80b7 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -1069,65 +1069,6 @@ static struct trace_event trace_wake_event = { .funcs = &trace_wake_funcs, }; -/* TRACE_SPECIAL */ -static enum print_line_t trace_special_print(struct trace_iterator *iter, - int flags, struct trace_event *event) -{ - struct special_entry *field; - - trace_assign_type(field, iter->ent); - - if (!trace_seq_printf(&iter->seq, "# %ld %ld %ld\n", - field->arg1, - field->arg2, - field->arg3)) - return TRACE_TYPE_PARTIAL_LINE; - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t trace_special_hex(struct trace_iterator *iter, - int flags, struct trace_event *event) -{ - struct special_entry *field; - struct trace_seq *s = &iter->seq; - - trace_assign_type(field, iter->ent); - - SEQ_PUT_HEX_FIELD_RET(s, field->arg1); - SEQ_PUT_HEX_FIELD_RET(s, field->arg2); - SEQ_PUT_HEX_FIELD_RET(s, field->arg3); - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t trace_special_bin(struct trace_iterator *iter, - int flags, struct trace_event *event) -{ - struct special_entry *field; - struct trace_seq *s = &iter->seq; - - trace_assign_type(field, iter->ent); - - SEQ_PUT_FIELD_RET(s, field->arg1); - SEQ_PUT_FIELD_RET(s, field->arg2); - SEQ_PUT_FIELD_RET(s, field->arg3); - - return TRACE_TYPE_HANDLED; -} - -static struct trace_event_functions trace_special_funcs = { - .trace = trace_special_print, - .raw = trace_special_print, - .hex = trace_special_hex, - .binary = trace_special_bin, -}; - -static struct trace_event trace_special_event = { - .type = TRACE_SPECIAL, - .funcs = &trace_special_funcs, -}; - /* TRACE_STACK */ static enum print_line_t trace_stack_print(struct trace_iterator *iter, @@ -1161,9 +1102,6 @@ static enum print_line_t trace_stack_print(struct trace_iterator *iter, static struct trace_event_functions trace_stack_funcs = { .trace = trace_stack_print, - .raw = trace_special_print, - .hex = trace_special_hex, - .binary = trace_special_bin, }; static struct trace_event trace_stack_event = { @@ -1194,9 +1132,6 @@ static enum print_line_t trace_user_stack_print(struct trace_iterator *iter, static struct trace_event_functions trace_user_stack_funcs = { .trace = trace_user_stack_print, - .raw = trace_special_print, - .hex = trace_special_hex, - .binary = trace_special_bin, }; static struct trace_event trace_user_stack_event = { @@ -1314,7 +1249,6 @@ static struct trace_event *events[] __initdata = { &trace_fn_event, &trace_ctx_event, &trace_wake_event, - &trace_special_event, &trace_stack_event, &trace_user_stack_event, &trace_bprint_event, diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 6ed05ee6cbc..155a415b320 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -13,7 +13,6 @@ static inline int trace_valid_entry(struct trace_entry *entry) case TRACE_WAKE: case TRACE_STACK: case TRACE_PRINT: - case TRACE_SPECIAL: case TRACE_BRANCH: case TRACE_GRAPH_ENT: case TRACE_GRAPH_RET: -- cgit v1.2.3