diff options
-rw-r--r-- | include/linux/interrupt.h | 5 | ||||
-rw-r--r-- | include/linux/kernel.h | 40 | ||||
-rw-r--r-- | include/trace/irq_event_types.h | 12 | ||||
-rw-r--r-- | kernel/softirq.c | 16 | ||||
-rw-r--r-- | kernel/trace/ring_buffer.c | 252 | ||||
-rw-r--r-- | kernel/trace/trace.c | 231 | ||||
-rw-r--r-- | kernel/trace/trace.h | 33 | ||||
-rw-r--r-- | kernel/trace/trace_event_types.h | 11 | ||||
-rw-r--r-- | kernel/trace/trace_events.c | 18 | ||||
-rw-r--r-- | kernel/trace/trace_events_stage_2.h | 2 | ||||
-rw-r--r-- | kernel/trace/trace_functions_graph.c | 6 | ||||
-rw-r--r-- | kernel/trace/trace_mmiotrace.c | 7 | ||||
-rw-r--r-- | kernel/trace/trace_output.c | 57 | ||||
-rw-r--r-- | kernel/trace/trace_printk.c | 150 | ||||
-rw-r--r-- | kernel/trace/trace_stack.c | 19 | ||||
-rw-r--r-- | kernel/trace/trace_workqueue.c | 20 |
16 files changed, 747 insertions, 132 deletions
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 472f11765f6..9b7e9d74347 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -258,6 +258,11 @@ enum NR_SOFTIRQS }; +/* map softirq index to softirq name. update 'softirq_to_name' in + * kernel/softirq.c when adding a new softirq. + */ +extern char *softirq_to_name[NR_SOFTIRQS]; + /* softirq mask and active fields moved to irq_cpustat_t in * asm/hardirq.h to get better cache usage. KAO */ diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 7742798c920..1daca3b062b 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -452,32 +452,46 @@ do { \ #define trace_printk(fmt, args...) \ do { \ - static const char *trace_printk_fmt \ - __attribute__((section("__trace_printk_fmt"))); \ - \ - if (!trace_printk_fmt) \ - trace_printk_fmt = fmt; \ - \ __trace_printk_check_format(fmt, ##args); \ - __trace_printk(_THIS_IP_, trace_printk_fmt, ##args); \ + if (__builtin_constant_p(fmt)) { \ + static const char *trace_printk_fmt \ + __attribute__((section("__trace_printk_fmt"))) = \ + __builtin_constant_p(fmt) ? fmt : NULL; \ + \ + __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ + } else \ + __trace_printk(_THIS_IP_, fmt, ##args); \ } while (0) extern int +__trace_bprintk(unsigned long ip, const char *fmt, ...) + __attribute__ ((format (printf, 2, 3))); + +extern int __trace_printk(unsigned long ip, const char *fmt, ...) __attribute__ ((format (printf, 2, 3))); +/* + * The double __builtin_constant_p is because gcc will give us an error + * if we try to allocate the static variable to fmt if it is not a + * constant. Even with the outer if statement. + */ #define ftrace_vprintk(fmt, vargs) \ do { \ - static const char *trace_printk_fmt \ - __attribute__((section("__trace_printk_fmt"))); \ - \ - if (!trace_printk_fmt) \ - trace_printk_fmt = fmt; \ + if (__builtin_constant_p(fmt)) { \ + static const char *trace_printk_fmt \ + __attribute__((section("__trace_printk_fmt"))) = \ + __builtin_constant_p(fmt) ? fmt : NULL; \ \ - __ftrace_vprintk(_THIS_IP_, trace_printk_fmt, vargs); \ + __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ + } else \ + __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ } while (0) extern int +__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); + +extern int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); extern void ftrace_dump(void); diff --git a/include/trace/irq_event_types.h b/include/trace/irq_event_types.h index 214bb928fe9..85964ebd47e 100644 --- a/include/trace/irq_event_types.h +++ b/include/trace/irq_event_types.h @@ -40,4 +40,16 @@ TRACE_EVENT(irq_handler_exit, __entry->irq, __entry->ret ? "handled" : "unhandled") ); +TRACE_FORMAT(softirq_entry, + TP_PROTO(struct softirq_action *h, struct softirq_action *vec), + TP_ARGS(h, vec), + TP_FMT("softirq=%d action=%s", (int)(h - vec), softirq_to_name[h-vec]) + ); + +TRACE_FORMAT(softirq_exit, + TP_PROTO(struct softirq_action *h, struct softirq_action *vec), + TP_ARGS(h, vec), + TP_FMT("softirq=%d action=%s", (int)(h - vec), softirq_to_name[h-vec]) + ); + #undef TRACE_SYSTEM diff --git a/kernel/softirq.c b/kernel/softirq.c index 7571bcb71be..a5e81231ca7 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -24,6 +24,7 @@ #include <linux/ftrace.h> #include <linux/smp.h> #include <linux/tick.h> +#include <trace/irq.h> #include <asm/irq.h> /* @@ -53,6 +54,12 @@ static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp static DEFINE_PER_CPU(struct task_struct *, ksoftirqd); +char *softirq_to_name[NR_SOFTIRQS] = { + "HI_SOFTIRQ", "TIMER_SOFTIRQ", "NET_TX_SOFTIRQ", "NET_RX_SOFTIRQ", + "BLOCK_SOFTIRQ", "TASKLET_SOFTIRQ", "SCHED_SOFTIRQ", "HRTIMER_SOFTIRQ", + "RCU_SOFTIRQ" +}; + /* * we cannot loop indefinitely here to avoid userspace starvation, * but we also don't want to introduce a worst case 1/HZ latency @@ -180,6 +187,9 @@ EXPORT_SYMBOL(local_bh_enable_ip); */ #define MAX_SOFTIRQ_RESTART 10 +DEFINE_TRACE(softirq_entry); +DEFINE_TRACE(softirq_exit); + asmlinkage void __do_softirq(void) { struct softirq_action *h; @@ -206,12 +216,14 @@ restart: if (pending & 1) { int prev_count = preempt_count(); + trace_softirq_entry(h, softirq_vec); h->action(h); - + trace_softirq_exit(h, softirq_vec); if (unlikely(prev_count != preempt_count())) { - printk(KERN_ERR "huh, entered softirq %td %p" + printk(KERN_ERR "huh, entered softirq %td %s %p" "with preempt_count %08x," " exited with %08x?\n", h - softirq_vec, + softirq_to_name[h - softirq_vec], h->action, prev_count, preempt_count()); preempt_count() = prev_count; } diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 178858492a8..58128ad2fde 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -16,11 +16,80 @@ #include <linux/init.h> #include <linux/hash.h> #include <linux/list.h> +#include <linux/cpu.h> #include <linux/fs.h> #include "trace.h" /* + * The ring buffer is made up of a list of pages. A separate list of pages is + * allocated for each CPU. A writer may only write to a buffer that is + * associated with the CPU it is currently executing on. A reader may read + * from any per cpu buffer. + * + * The reader is special. For each per cpu buffer, the reader has its own + * reader page. When a reader has read the entire reader page, this reader + * page is swapped with another page in the ring buffer. + * + * Now, as long as the writer is off the reader page, the reader can do what + * ever it wants with that page. The writer will never write to that page + * again (as long as it is out of the ring buffer). + * + * Here's some silly ASCII art. + * + * +------+ + * |reader| RING BUFFER + * |page | + * +------+ +---+ +---+ +---+ + * | |-->| |-->| | + * +---+ +---+ +---+ + * ^ | + * | | + * +---------------+ + * + * + * +------+ + * |reader| RING BUFFER + * |page |------------------v + * +------+ +---+ +---+ +---+ + * | |-->| |-->| | + * +---+ +---+ +---+ + * ^ | + * | | + * +---------------+ + * + * + * +------+ + * |reader| RING BUFFER + * |page |------------------v + * +------+ +---+ +---+ +---+ + * ^ | |-->| |-->| | + * | +---+ +---+ +---+ + * | | + * | | + * +------------------------------+ + * + * + * +------+ + * |buffer| RING BUFFER + * |page |------------------v + * +------+ +---+ +---+ +---+ + * ^ | | | |-->| | + * | New +---+ +---+ +---+ + * | Reader------^ | + * | page | + * +------------------------------+ + * + * + * After we make this swap, the reader can hand this page off to the splice + * code and be done with it. It can even allocate a new page if it needs to + * and swap that into the ring buffer. + * + * We will be using cmpxchg soon to make all this lockless. + * + */ + +/* * A fast way to enable or disable all ring buffers is to * call tracing_on or tracing_off. Turning off the ring buffers * prevents all ring buffers from being recorded to. @@ -301,6 +370,10 @@ struct ring_buffer { struct mutex mutex; struct ring_buffer_per_cpu **buffers; + +#ifdef CONFIG_HOTPLUG_CPU + struct notifier_block cpu_notify; +#endif }; struct ring_buffer_iter { @@ -459,6 +532,11 @@ static void rb_free_cpu_buffer(struct ring_buffer_per_cpu *cpu_buffer) */ extern int ring_buffer_page_too_big(void); +#ifdef CONFIG_HOTPLUG_CPU +static int __cpuinit rb_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu); +#endif + /** * ring_buffer_alloc - allocate a new ring_buffer * @size: the size in bytes per cpu that is needed. @@ -496,7 +574,8 @@ struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags) if (buffer->pages == 1) buffer->pages++; - cpumask_copy(buffer->cpumask, cpu_possible_mask); + get_online_cpus(); + cpumask_copy(buffer->cpumask, cpu_online_mask); buffer->cpus = nr_cpu_ids; bsize = sizeof(void *) * nr_cpu_ids; @@ -512,6 +591,13 @@ struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags) goto fail_free_buffers; } +#ifdef CONFIG_HOTPLUG_CPU + buffer->cpu_notify.notifier_call = rb_cpu_notify; + buffer->cpu_notify.priority = 0; + register_cpu_notifier(&buffer->cpu_notify); +#endif + + put_online_cpus(); mutex_init(&buffer->mutex); return buffer; @@ -525,6 +611,7 @@ struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags) fail_free_cpumask: free_cpumask_var(buffer->cpumask); + put_online_cpus(); fail_free_buffer: kfree(buffer); @@ -541,9 +628,17 @@ ring_buffer_free(struct ring_buffer *buffer) { int cpu; + get_online_cpus(); + +#ifdef CONFIG_HOTPLUG_CPU + unregister_cpu_notifier(&buffer->cpu_notify); +#endif + for_each_buffer_cpu(buffer, cpu) rb_free_cpu_buffer(buffer->buffers[cpu]); + put_online_cpus(); + free_cpumask_var(buffer->cpumask); kfree(buffer); @@ -649,16 +744,15 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) return size; mutex_lock(&buffer->mutex); + get_online_cpus(); nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); if (size < buffer_size) { /* easy case, just free pages */ - if (RB_WARN_ON(buffer, nr_pages >= buffer->pages)) { - mutex_unlock(&buffer->mutex); - return -1; - } + if (RB_WARN_ON(buffer, nr_pages >= buffer->pages)) + goto out_fail; rm_pages = buffer->pages - nr_pages; @@ -677,10 +771,8 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) * add these pages to the cpu_buffers. Otherwise we just free * them all and return -ENOMEM; */ - if (RB_WARN_ON(buffer, nr_pages <= buffer->pages)) { - mutex_unlock(&buffer->mutex); - return -1; - } + if (RB_WARN_ON(buffer, nr_pages <= buffer->pages)) + goto out_fail; new_pages = nr_pages - buffer->pages; @@ -705,13 +797,12 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) rb_insert_pages(cpu_buffer, &pages, new_pages); } - if (RB_WARN_ON(buffer, !list_empty(&pages))) { - mutex_unlock(&buffer->mutex); - return -1; - } + if (RB_WARN_ON(buffer, !list_empty(&pages))) + goto out_fail; out: buffer->pages = nr_pages; + put_online_cpus(); mutex_unlock(&buffer->mutex); return size; @@ -721,8 +812,18 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) list_del_init(&bpage->list); free_buffer_page(bpage); } + put_online_cpus(); mutex_unlock(&buffer->mutex); return -ENOMEM; + + /* + * Something went totally wrong, and we are too paranoid + * to even clean up the mess. + */ + out_fail: + put_online_cpus(); + mutex_unlock(&buffer->mutex); + return -1; } EXPORT_SYMBOL_GPL(ring_buffer_resize); @@ -1564,12 +1665,15 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_enable_cpu); unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; + unsigned long ret; if (!cpumask_test_cpu(cpu, buffer->cpumask)) return 0; cpu_buffer = buffer->buffers[cpu]; - return cpu_buffer->entries; + ret = cpu_buffer->entries; + + return ret; } EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu); @@ -1581,12 +1685,15 @@ EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu); unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; + unsigned long ret; if (!cpumask_test_cpu(cpu, buffer->cpumask)) return 0; cpu_buffer = buffer->buffers[cpu]; - return cpu_buffer->overrun; + ret = cpu_buffer->overrun; + + return ret; } EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu); @@ -1663,9 +1770,14 @@ static void rb_iter_reset(struct ring_buffer_iter *iter) */ void ring_buffer_iter_reset(struct ring_buffer_iter *iter) { - struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer; + struct ring_buffer_per_cpu *cpu_buffer; unsigned long flags; + if (!iter) + return; + + cpu_buffer = iter->cpu_buffer; + spin_lock_irqsave(&cpu_buffer->reader_lock, flags); rb_iter_reset(iter); spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); @@ -1900,9 +2012,6 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) struct buffer_page *reader; int nr_loops = 0; - if (!cpumask_test_cpu(cpu, buffer->cpumask)) - return NULL; - cpu_buffer = buffer->buffers[cpu]; again: @@ -2031,6 +2140,9 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) struct ring_buffer_event *event; unsigned long flags; + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return NULL; + spin_lock_irqsave(&cpu_buffer->reader_lock, flags); event = rb_buffer_peek(buffer, cpu, ts); spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); @@ -2071,24 +2183,31 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts) struct ring_buffer_event * ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts) { - struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu]; - struct ring_buffer_event *event; + struct ring_buffer_per_cpu *cpu_buffer; + struct ring_buffer_event *event = NULL; unsigned long flags; + /* might be called in atomic */ + preempt_disable(); + if (!cpumask_test_cpu(cpu, buffer->cpumask)) - return NULL; + goto out; + cpu_buffer = buffer->buffers[cpu]; spin_lock_irqsave(&cpu_buffer->reader_lock, flags); event = rb_buffer_peek(buffer, cpu, ts); if (!event) - goto out; + goto out_unlock; rb_advance_reader(cpu_buffer); - out: + out_unlock: spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + out: + preempt_enable(); + return event; } EXPORT_SYMBOL_GPL(ring_buffer_consume); @@ -2268,6 +2387,7 @@ int ring_buffer_empty(struct ring_buffer *buffer) if (!rb_per_cpu_empty(cpu_buffer)) return 0; } + return 1; } EXPORT_SYMBOL_GPL(ring_buffer_empty); @@ -2280,12 +2400,16 @@ EXPORT_SYMBOL_GPL(ring_buffer_empty); int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; + int ret; if (!cpumask_test_cpu(cpu, buffer->cpumask)) return 1; cpu_buffer = buffer->buffers[cpu]; - return rb_per_cpu_empty(cpu_buffer); + ret = rb_per_cpu_empty(cpu_buffer); + + + return ret; } EXPORT_SYMBOL_GPL(ring_buffer_empty_cpu); @@ -2304,32 +2428,35 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, { struct ring_buffer_per_cpu *cpu_buffer_a; struct ring_buffer_per_cpu *cpu_buffer_b; + int ret = -EINVAL; if (!cpumask_test_cpu(cpu, buffer_a->cpumask) || !cpumask_test_cpu(cpu, buffer_b->cpumask)) - return -EINVAL; + goto out; /* At least make sure the two buffers are somewhat the same */ if (buffer_a->pages != buffer_b->pages) - return -EINVAL; + goto out; + + ret = -EAGAIN; if (ring_buffer_flags != RB_BUFFERS_ON) - return -EAGAIN; + goto out; if (atomic_read(&buffer_a->record_disabled)) - return -EAGAIN; + goto out; if (atomic_read(&buffer_b->record_disabled)) - return -EAGAIN; + goto out; cpu_buffer_a = buffer_a->buffers[cpu]; cpu_buffer_b = buffer_b->buffers[cpu]; if (atomic_read(&cpu_buffer_a->record_disabled)) - return -EAGAIN; + goto out; if (atomic_read(&cpu_buffer_b->record_disabled)) - return -EAGAIN; + goto out; /* * We can't do a synchronize_sched here because this @@ -2349,7 +2476,9 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, atomic_dec(&cpu_buffer_a->record_disabled); atomic_dec(&cpu_buffer_b->record_disabled); - return 0; + ret = 0; +out: + return ret; } EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu); @@ -2464,27 +2593,30 @@ int ring_buffer_read_page(struct ring_buffer *buffer, u64 save_timestamp; int ret = -1; + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + goto out; + /* * If len is not big enough to hold the page header, then * we can not copy anything. */ if (len <= BUF_PAGE_HDR_SIZE) - return -1; + goto out; len -= BUF_PAGE_HDR_SIZE; if (!data_page) - return -1; + goto out; bpage = *data_page; if (!bpage) - return -1; + goto out; spin_lock_irqsave(&cpu_buffer->reader_lock, flags); reader = rb_get_reader_page(cpu_buffer); if (!reader) - goto out; + goto out_unlock; event = rb_reader_event(cpu_buffer); @@ -2506,7 +2638,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer, unsigned int size; if (full) - goto out; + goto out_unlock; if (len > (commit - read)) len = (commit - read); @@ -2514,7 +2646,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer, size = rb_event_length(event); if (len < size) - goto out; + goto out_unlock; /* save the current timestamp, since the user will need it */ save_timestamp = cpu_buffer->read_stamp; @@ -2553,9 +2685,10 @@ int ring_buffer_read_page(struct ring_buffer *buffer, } ret = read; - out: + out_unlock: spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + out: return ret; } @@ -2629,3 +2762,42 @@ static __init int rb_init_debugfs(void) } fs_initcall(rb_init_debugfs); + +#ifdef CONFIG_HOTPLUG_CPU +static int __cpuinit rb_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + struct ring_buffer *buffer = + container_of(self, struct ring_buffer, cpu_notify); + long cpu = (long)hcpu; + + switch (action) { + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: + if (cpu_isset(cpu, *buffer->cpumask)) + return NOTIFY_OK; + + buffer->buffers[cpu] = + rb_allocate_cpu_buffer(buffer, cpu); + if (!buffer->buffers[cpu]) { + WARN(1, "failed to allocate ring buffer on CPU %ld\n", + cpu); + return NOTIFY_OK; + } + smp_wmb(); + cpu_set(cpu, *buffer->cpumask); + break; + case CPU_DOWN_PREPARE: + case CPU_DOWN_PREPARE_FROZEN: + /* + * Do nothing. + * If we were to free the buffer, then the user would + * lose any trace that was in the buffer. + */ + break; + default: + break; + } + return NOTIFY_OK; +} +#endif diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5c9c6d90705..dbb077d8a17 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -45,6 +45,12 @@ unsigned long __read_mostly tracing_max_latency; unsigned long __read_mostly tracing_thresh; /* + * On boot up, the ring buffer is set to the minimum size, so that + * we do not waste memory on systems that are not using tracing. + */ +static int ring_buffer_expanded; + +/* * We need to change this state when a selftest is running. * A selftest will lurk into the ring-buffer to count the * entries inserted during the selftest although some concurrent @@ -128,6 +134,8 @@ static int __init set_ftrace(char *str) { strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); default_bootup_tracer = bootup_tracer_buf; + /* We are using ftrace early, expand it */ + ring_buffer_expanded = 1; return 1; } __setup("ftrace=", set_ftrace); @@ -1171,10 +1179,10 @@ void trace_graph_return(struct ftrace_graph_ret *trace) /** - * trace_vprintk - write binary msg to tracing buffer + * trace_vbprintk - write binary msg to tracing buffer * */ -int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) +int trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args) { static raw_spinlock_t trace_buf_lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; @@ -1183,7 +1191,7 @@ int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) struct ring_buffer_event *event; struct trace_array *tr = &global_trace; struct trace_array_cpu *data; - struct print_entry *entry; + struct bprint_entry *entry; unsigned long flags; int resched; int cpu, len = 0, size, pc; @@ -1211,7 +1219,7 @@ int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) goto out_unlock; size = sizeof(*entry) + sizeof(u32) * len; - event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, flags, pc); + event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); if (!event) goto out_unlock; entry = ring_buffer_event_data(event); @@ -1232,6 +1240,60 @@ out: return len; } +EXPORT_SYMBOL_GPL(trace_vbprintk); + +int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) +{ + static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; + static char trace_buf[TRACE_BUF_SIZE]; + + struct ring_buffer_event *event; + struct trace_array *tr = &global_trace; + struct trace_array_cpu *data; + int cpu, len = 0, size, pc; + struct print_entry *entry; + unsigned long irq_flags; + + if (tracing_disabled || tracing_selftest_running) + return 0; + + pc = preempt_count(); + preempt_disable_notrace(); + cpu = raw_smp_processor_id(); + data = tr->data[cpu]; + + if (unlikely(atomic_read(&data->disabled))) + goto out; + + pause_graph_tracing(); + raw_local_irq_save(irq_flags); + __raw_spin_lock(&trace_buf_lock); + len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); + + len = min(len, TRACE_BUF_SIZE-1); + trace_buf[len] = 0; + + size = sizeof(*entry) + len + 1; + event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); + if (!event) + goto out_unlock; + entry = ring_buffer_event_data(event); + entry->ip = ip; + entry->depth = depth; + + memcpy(&entry->buf, trace_buf, len); + entry->buf[len] = 0; + ring_buffer_unlock_commit(tr->buffer, event); + + out_unlock: + __raw_spin_unlock(&trace_buf_lock); + raw_local_irq_restore(irq_flags); + unpause_graph_tracing(); + out: + preempt_enable_notrace(); + + return len; +} EXPORT_SYMBOL_GPL(trace_vprintk); enum trace_file_type { @@ -1620,6 +1682,22 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) return TRACE_TYPE_HANDLED; } +static enum print_line_t print_bprintk_msg_only(struct trace_iterator *iter) +{ + struct trace_seq *s = &iter->seq; + struct trace_entry *entry = iter->ent; + struct bprint_entry *field; + int ret; + + trace_assign_type(field, entry); + + ret = trace_seq_bprintf(s, field->fmt, field->buf); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + return TRACE_TYPE_HANDLED; +} + static enum print_line_t print_printk_msg_only(struct trace_iterator *iter) { struct trace_seq *s = &iter->seq; @@ -1629,7 +1707,7 @@ static enum print_line_t print_printk_msg_only(struct trace_iterator *iter) trace_assign_type(field, entry); - ret = trace_seq_bprintf(s, field->fmt, field->buf); + ret = trace_seq_printf(s, "%s", field->buf); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -1658,6 +1736,19 @@ static int trace_empty(struct trace_iterator *iter) { int cpu; + /* If we are looking at one CPU buffer, only check that one */ + if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { + cpu = iter->cpu_file; + if (iter->buffer_iter[cpu]) { + if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) + return 0; + } else { + if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) + return 0; + } + return 1; + } + for_each_tracing_cpu(cpu) { if (iter->buffer_iter[cpu]) { if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) @@ -1681,6 +1772,11 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter) return ret; } + if (iter->ent->type == TRACE_BPRINT && + trace_flags & TRACE_ITER_PRINTK && + trace_flags & TRACE_ITER_PRINTK_MSGONLY) + return print_bprintk_msg_only(iter); + if (iter->ent->type == TRACE_PRINT && trace_flags & TRACE_ITER_PRINTK && trace_flags & TRACE_ITER_PRINTK_MSGONLY) @@ -1784,17 +1880,11 @@ __tracing_open(struct inode *inode, struct file *file) iter->buffer_iter[cpu] = ring_buffer_read_start(iter->tr->buffer, cpu); - - if (!iter->buffer_iter[cpu]) - goto fail_buffer; } } else { cpu = iter->cpu_file; iter->buffer_iter[cpu] = ring_buffer_read_start(iter->tr->buffer, cpu); - - if (!iter->buffer_iter[cpu]) - goto fail; } /* TODO stop tracer */ @@ -2315,6 +2405,75 @@ int tracer_init(struct tracer *t, struct trace_array *tr) return t->init(tr); } +static int tracing_resize_ring_buffer(unsigned long size) +{ + int ret; + + /* + * If kernel or user changes the size of the ring buffer + * we use the size that was given, and we can forget about + * expanding it later. + */ + ring_buffer_expanded = 1; + + ret = ring_buffer_resize(global_trace.buffer, size); + if (ret < 0) + return ret; + + ret = ring_buffer_resize(max_tr.buffer, size); + if (ret < 0) { + int r; + + r = ring_buffer_resize(global_trace.buffer, + global_trace.entries); + if (r < 0) { + /* + * AARGH! We are left with different + * size max buffer!!!! + * The max buffer is our "snapshot" buffer. + * When a tracer needs a snapshot (one of the + * latency tracers), it swaps the max buffer + * with the saved snap shot. We succeeded to + * update the size of the main buffer, but failed to + * update the size of the max buffer. But when we tried + * to reset the main buffer to the original size, we + * failed there too. This is very unlikely to + * happen, but if it does, warn and kill all + * tracing. + */ + WARN_ON(1); + tracing_disabled = 1; + } + return ret; + } + + global_trace.entries = size; + + return ret; +} + +/** + * tracing_update_buffers - used by tracing facility to expand ring buffers + * + * To save on memory when the tracing is never used on a system with it + * configured in. The ring buffers are set to a minimum size. But once + * a user starts to use the tracing facility, then they need to grow + * to their default size. + * + * This function is to be called when a tracer is about to be used. + */ +int tracing_update_buffers(void) +{ + int ret = 0; + + mutex_lock(&trace_types_lock); + if (!ring_buffer_expanded) + ret = tracing_resize_ring_buffer(trace_buf_size); + mutex_unlock(&trace_types_lock); + + return ret; +} + struct trace_option_dentry; static struct trace_option_dentry * @@ -2331,6 +2490,14 @@ static int tracing_set_tracer(const char *buf) int ret = 0; mutex_lock(&trace_types_lock); + + if (!ring_buffer_expanded) { + ret = tracing_resize_ring_buffer(trace_buf_size); + if (ret < 0) + return ret; + ret = 0; + } + for (t = trace_types; t; t = t->next) { if (strcmp(t->name, buf) == 0) break; @@ -2856,10 +3023,18 @@ tracing_entries_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_array *tr = filp->private_data; - char buf[64]; + char buf[96]; int r; - r = sprintf(buf, "%lu\n", tr->entries >> 10); + mutex_lock(&trace_types_lock); + if (!ring_buffer_expanded) + r = sprintf(buf, "%lu (expanded: %lu)\n", + tr->entries >> 10, + trace_buf_size >> 10); + else + r = sprintf(buf, "%lu\n", tr->entries >> 10); + mutex_unlock(&trace_types_lock); + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); } @@ -2903,28 +3078,11 @@ tracing_entries_write(struct file *filp, const char __user *ubuf, val <<= 10; if (val != global_trace.entries) { - ret = ring_buffer_resize(global_trace.buffer, val); + ret = tracing_resize_ring_buffer(val); if (ret < 0) { cnt = ret; goto out; } - - ret = ring_buffer_resize(max_tr.buffer, val); - if (ret < 0) { - int r; - cnt = ret; - r = ring_buffer_resize(global_trace.buffer, - global_trace.entries); - if (r < 0) { - /* AARGH! We are left with different - * size max buffer!!!! */ - WARN_ON(1); - tracing_disabled = 1; - } - goto out; - } - - global_trace.entries = val; } filp->f_pos += cnt; @@ -3916,6 +4074,7 @@ void ftrace_dump(void) __init static int tracer_alloc_buffers(void) { struct trace_array_cpu *data; + int ring_buf_size; int i; int ret = -ENOMEM; @@ -3928,12 +4087,18 @@ __init static int tracer_alloc_buffers(void) if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) goto out_free_tracing_cpumask; + /* To save memory, keep the ring buffer size to its minimum */ + if (ring_buffer_expanded) + ring_buf_size = trace_buf_size; + else + ring_buf_size = 1; + cpumask_copy(tracing_buffer_mask, cpu_possible_mask); cpumask_copy(tracing_cpumask, cpu_all_mask); cpumask_clear(tracing_reader_cpumask); /* TODO: make the number of buffers hot pluggable with CPUS */ - global_trace.buffer = ring_buffer_alloc(trace_buf_size, + global_trace.buffer = ring_buffer_alloc(ring_buf_size, TRACE_BUFFER_FLAGS); if (!global_trace.buffer) { printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); @@ -3944,7 +4109,7 @@ __init static int tracer_alloc_buffers(void) #ifdef CONFIG_TRACER_MAX_TRACE - max_tr.buffer = ring_buffer_alloc(trace_buf_size, + max_tr.buffer = ring_buffer_alloc(ring_buf_size, TRACE_BUFFER_FLAGS); if (!max_tr.buffer) { printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index c5e1d8865fe..35cfa7bbaf3 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -20,6 +20,7 @@ enum trace_type { TRACE_WAKE, TRACE_STACK, TRACE_PRINT, + TRACE_BPRINT, TRACE_SPECIAL, TRACE_MMIO_RW, TRACE_MMIO_MAP, @@ -117,7 +118,7 @@ struct userstack_entry { /* * trace_printk entry: */ -struct print_entry { +struct bprint_entry { struct trace_entry ent; unsigned long ip; int depth; @@ -125,6 +126,13 @@ struct print_entry { u32 buf[]; }; +struct print_entry { + struct trace_entry ent; + unsigned long ip; + int depth; + char buf[]; +}; + #define TRACE_OLD_SIZE 88 struct trace_field_cont { @@ -286,6 +294,7 @@ extern void __ftrace_bad_type(void); IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 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); \ @@ -570,6 +579,8 @@ extern int trace_selftest_startup_branch(struct tracer *trace, extern void *head_page(struct trace_array_cpu *data); extern long ns2usecs(cycle_t nsec); extern int +trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args); +extern int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args); extern unsigned long trace_flags; @@ -737,6 +748,9 @@ static inline void trace_branch_disable(void) } #endif /* CONFIG_BRANCH_TRACER */ +/* set ring buffers to default size if not already done so */ +int tracing_update_buffers(void); + /* trace event type bit fields, not numeric */ enum { TRACE_EVENT_TYPE_PRINTF = 1, @@ -759,4 +773,21 @@ void event_trace_printk(unsigned long ip, const char *fmt, ...); extern struct ftrace_event_call __start_ftrace_events[]; extern struct ftrace_event_call __stop_ftrace_events[]; +extern const char *__start___trace_bprintk_fmt[]; +extern const char *__stop___trace_bprintk_fmt[]; + +#define event_trace_printk(ip, fmt, args...) \ +do { \ + __trace_printk_check_format(fmt, ##args); \ + tracing_record_cmdline(current); \ + if (__builtin_constant_p(fmt)) { \ + static const char *trace_printk_fmt \ + __attribute__((section("__trace_printk_fmt"))) = \ + __builtin_constant_p(fmt) ? fmt : NULL; \ + \ + __trace_bprintk(ip, trace_printk_fmt, ##args); \ + } else \ + __trace_printk(ip, fmt, ##args); \ +} while (0) + #endif /* _LINUX_KERNEL_TRACE_H */ diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h index 5cca4c978bd..019915063fe 100644 --- a/kernel/trace/trace_event_types.h +++ b/kernel/trace/trace_event_types.h @@ -102,7 +102,7 @@ TRACE_EVENT_FORMAT(user_stack, TRACE_USER_STACK, userstack_entry, ignore, "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n") ); -TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore, +TRACE_EVENT_FORMAT(bprint, TRACE_BPRINT, bprint_entry, ignore, TRACE_STRUCT( TRACE_FIELD(unsigned long, ip, ip) TRACE_FIELD(unsigned int, depth, depth) @@ -112,6 +112,15 @@ TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore, TP_RAW_FMT("%08lx (%d) fmt:%p %s") ); +TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore, + TRACE_STRUCT( + TRACE_FIELD(unsigned long, ip, ip) + TRACE_FIELD(unsigned int, depth, depth) + TRACE_FIELD_ZERO_CHAR(buf) + ), + TP_RAW_FMT("%08lx (%d) fmt:%p %s") +); + TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore, TRACE_STRUCT( TRACE_FIELD(unsigned int, line, line) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 769dfd00fc8..238ea95a411 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -24,16 +24,6 @@ static DEFINE_MUTEX(event_mutex); (unsigned long)event < (unsigned long)__stop_ftrace_events; \ event++) -void event_trace_printk(unsigned long ip, const char *fmt, ...) -{ - va_list ap; - - va_start(ap, fmt); - tracing_record_cmdline(current); - trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); - va_end(ap); -} - static void ftrace_clear_events(void) { struct ftrace_event_call *call = (void *)__start_ftrace_events; @@ -141,6 +131,10 @@ ftrace_event_write(struct file *file, const char __user *ubuf, if (!cnt || cnt < 0) return 0; + ret = tracing_update_buffers(); + if (ret < 0) + return ret; + ret = get_user(ch, ubuf++); if (ret) return ret; @@ -331,6 +325,10 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, if (ret < 0) return ret; + ret = tracing_update_buffers(); + if (ret < 0) + return ret; + switch (val) { case 0: case 1: diff --git a/kernel/trace/trace_events_stage_2.h b/kernel/trace/trace_events_stage_2.h index ca347afd6aa..5117c43f5c6 100644 --- a/kernel/trace/trace_events_stage_2.h +++ b/kernel/trace/trace_events_stage_2.h @@ -57,7 +57,7 @@ ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \ \ field = (typeof(field))entry; \ \ - ret = trace_seq_printf(s, print); \ + ret = trace_seq_printf(s, #call ": " print); \ if (!ret) \ return TRACE_TYPE_PARTIAL_LINE; \ \ diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 8566c14b3e9..4c388607ed6 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -684,7 +684,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s, } static enum print_line_t -print_graph_comment(struct print_entry *trace, struct trace_seq *s, +print_graph_comment(struct bprint_entry *trace, struct trace_seq *s, struct trace_entry *ent, struct trace_iterator *iter) { int i; @@ -781,8 +781,8 @@ print_graph_function(struct trace_iterator *iter) trace_assign_type(field, entry); return print_graph_return(&field->ret, s, entry, iter); } - case TRACE_PRINT: { - struct print_entry *field; + case TRACE_BPRINT: { + struct bprint_entry *field; trace_assign_type(field, entry); return print_graph_comment(field, s, entry, iter); } diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index 23e346a734c..f095916e477 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -254,6 +254,7 @@ static enum print_line_t mmio_print_mark(struct trace_iterator *iter) { struct trace_entry *entry = iter->ent; struct print_entry *print = (struct print_entry *)entry; + const char *msg = print->buf; struct trace_seq *s = &iter->seq; unsigned long long t = ns2usecs(iter->ts); unsigned long usec_rem = do_div(t, USEC_PER_SEC); @@ -261,11 +262,7 @@ static enum print_line_t mmio_print_mark(struct trace_iterator *iter) int ret; /* The trailing newline must be in the message. */ - ret = trace_seq_printf(s, "MARK %u.%06lu ", secs, usec_rem); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - ret = trace_seq_bprintf(s, print->fmt, print->buf); + ret = trace_seq_printf(s, "MARK %u.%06lu %s", secs, usec_rem, msg); if (!ret) return TRACE_TYPE_PARTIAL_LINE; diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 491832af9ba..ea9d3b410c7 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -832,13 +832,13 @@ static struct trace_event trace_user_stack_event = { .binary = trace_special_bin, }; -/* TRACE_PRINT */ +/* TRACE_BPRINT */ static enum print_line_t -trace_print_print(struct trace_iterator *iter, int flags) +trace_bprint_print(struct trace_iterator *iter, int flags) { struct trace_entry *entry = iter->ent; struct trace_seq *s = &iter->seq; - struct print_entry *field; + struct bprint_entry *field; trace_assign_type(field, entry); @@ -858,9 +858,10 @@ trace_print_print(struct trace_iterator *iter, int flags) } -static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags) +static enum print_line_t +trace_bprint_raw(struct trace_iterator *iter, int flags) { - struct print_entry *field; + struct bprint_entry *field; struct trace_seq *s = &iter->seq; trace_assign_type(field, iter->ent); @@ -878,12 +879,55 @@ static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags) } +static struct trace_event trace_bprint_event = { + .type = TRACE_BPRINT, + .trace = trace_bprint_print, + .raw = trace_bprint_raw, +}; + +/* TRACE_PRINT */ +static enum print_line_t trace_print_print(struct trace_iterator *iter, + int flags) +{ + struct print_entry *field; + struct trace_seq *s = &iter->seq; + + trace_assign_type(field, iter->ent); + + if (!seq_print_ip_sym(s, field->ip, flags)) + goto partial; + + if (!trace_seq_printf(s, ": %s", field->buf)) + goto partial; + + return TRACE_TYPE_HANDLED; + + partial: + return TRACE_TYPE_PARTIAL_LINE; +} + +static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags) +{ + struct print_entry *field; + + trace_assign_type(field, iter->ent); + + if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf)) + goto partial; + + return TRACE_TYPE_HANDLED; + + partial: + return TRACE_TYPE_PARTIAL_LINE; +} + static struct trace_event trace_print_event = { - .type = TRACE_PRINT, + .type = TRACE_PRINT, .trace = trace_print_print, .raw = trace_print_raw, }; + static struct trace_event *events[] __initdata = { &trace_fn_event, &trace_ctx_event, @@ -891,6 +935,7 @@ static struct trace_event *events[] __initdata = { &trace_special_event, &trace_stack_event, &trace_user_stack_event, + &trace_bprint_event, &trace_print_event, NULL }; diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index a50aea22e92..486785214e3 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -4,18 +4,19 @@ * Copyright (C) 2008 Lai Jiangshan <laijs@cn.fujitsu.com> * */ +#include <linux/seq_file.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> #include <linux/kernel.h> #include <linux/ftrace.h> #include <linux/string.h> +#include <linux/module.h> +#include <linux/marker.h> +#include <linux/mutex.h> #include <linux/ctype.h> #include <linux/list.h> -#include <linux/mutex.h> #include <linux/slab.h> -#include <linux/module.h> -#include <linux/seq_file.h> #include <linux/fs.h> -#include <linux/marker.h> -#include <linux/uaccess.h> #include "trace.h" @@ -99,7 +100,7 @@ struct notifier_block module_trace_bprintk_format_nb = { .notifier_call = module_trace_bprintk_format_notify, }; -int __trace_printk(unsigned long ip, const char *fmt, ...) +int __trace_bprintk(unsigned long ip, const char *fmt, ...) { int ret; va_list ap; @@ -111,13 +112,13 @@ int __trace_printk(unsigned long ip, const char *fmt, ...) return 0; va_start(ap, fmt); - ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); + ret = trace_vbprintk(ip, task_curr_ret_stack(current), fmt, ap); va_end(ap); return ret; } -EXPORT_SYMBOL_GPL(__trace_printk); +EXPORT_SYMBOL_GPL(__trace_bprintk); -int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) +int __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap) { if (unlikely(!fmt)) return 0; @@ -125,10 +126,141 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) if (!(trace_flags & TRACE_ITER_PRINTK)) return 0; + return trace_vbprintk(ip, task_curr_ret_stack(current), fmt, ap); +} +EXPORT_SYMBOL_GPL(__ftrace_vbprintk); + +int __trace_printk(unsigned long ip, const char *fmt, ...) +{ + int ret; + va_list ap; + + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + + va_start(ap, fmt); + ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); + va_end(ap); + return ret; +} +EXPORT_SYMBOL_GPL(__trace_printk); + +int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) +{ + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + return trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); } EXPORT_SYMBOL_GPL(__ftrace_vprintk); +static void * +t_next(struct seq_file *m, void *v, loff_t *pos) +{ + const char **fmt = m->private; + const char **next = fmt; + + (*pos)++; + + if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt) + return NULL; + + next = fmt; + m->private = ++next; + + return fmt; +} + +static void *t_start(struct seq_file *m, loff_t *pos) +{ + return t_next(m, NULL, pos); +} + +static int t_show(struct seq_file *m, void *v) +{ + const char **fmt = v; + const char *str = *fmt; + int i; + + seq_printf(m, "0x%lx : \"", (unsigned long)fmt); + + /* + * Tabs and new lines need to be converted. + */ + for (i = 0; str[i]; i++) { + switch (str[i]) { + case '\n': + seq_puts(m, "\\n"); + break; + case '\t': + seq_puts(m, "\\t"); + break; + case '\\': + seq_puts(m, "\\"); + break; + case '"': + seq_puts(m, "\\\""); + break; + default: + seq_putc(m, str[i]); + } + } + seq_puts(m, "\"\n"); + + return 0; +} + +static void t_stop(struct seq_file *m, void *p) +{ +} + +static const struct seq_operations show_format_seq_ops = { + .start = t_start, + .next = t_next, + .show = t_show, + .stop = t_stop, +}; + +static int +ftrace_formats_open(struct inode *inode, struct file *file) +{ + int ret; + + ret = seq_open(file, &show_format_seq_ops); + if (!ret) { + struct seq_file *m = file->private_data; + + m->private = __start___trace_bprintk_fmt; + } + return ret; +} + +static const struct file_operations ftrace_formats_fops = { + .open = ftrace_formats_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static __init int init_trace_printk_function_export(void) +{ + struct dentry *d_tracer; + struct dentry *entry; + + d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; + + entry = debugfs_create_file("printk_formats", 0444, d_tracer, + NULL, &ftrace_formats_fops); + if (!entry) + pr_warning("Could not create debugfs " + "'printk_formats' entry\n"); + + return 0; +} + +fs_initcall(init_trace_printk_function_export); static __init int init_trace_printk(void) { diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index d0871bc0aca..91ccbf396c9 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -245,16 +245,31 @@ static int trace_lookup_stack(struct seq_file *m, long i) #endif } +static void print_disabled(struct seq_file *m) +{ + seq_puts(m, "#\n" + "# Stack tracer disabled\n" + "#\n" + "# To enable the stack tracer, either add 'stacktrace' to the\n" + "# kernel command line\n" + "# or 'echo 1 > /proc/sys/kernel/stack_tracer_enabled'\n" + "#\n"); +} + static int t_show(struct seq_file *m, void *v) { long i; int size; if (v == SEQ_START_TOKEN) { - seq_printf(m, " Depth Size Location" + seq_printf(m, " Depth Size Location" " (%d entries)\n" - " ----- ---- --------\n", + " ----- ---- --------\n", max_stack_trace.nr_entries); + + if (!stack_tracer_enabled && !max_stack_size) + print_disabled(m); + return 0; } diff --git a/kernel/trace/trace_workqueue.c b/kernel/trace/trace_workqueue.c index fb5ccac8bbc..9ab035b58cf 100644 --- a/kernel/trace/trace_workqueue.c +++ b/kernel/trace/trace_workqueue.c @@ -193,12 +193,20 @@ static int workqueue_stat_show(struct seq_file *s, void *p) struct cpu_workqueue_stats *cws = p; unsigned long flags; int cpu = cws->cpu; - struct task_struct *tsk = find_task_by_vpid(cws->pid); - - seq_printf(s, "%3d %6d %6u %s\n", cws->cpu, - atomic_read(&cws->inserted), - cws->executed, - tsk ? tsk->comm : "<...>"); + struct pid *pid; + struct task_struct *tsk; + + pid = find_get_pid(cws->pid); + if (pid) { + tsk = get_pid_task(pid, PIDTYPE_PID); + if (tsk) { + seq_printf(s, "%3d %6d %6u %s\n", cws->cpu, + atomic_read(&cws->inserted), cws->executed, + tsk->comm); + put_task_struct(tsk); + } + put_pid(pid); + } spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); if (&cws->list == workqueue_cpu_stat(cpu)->list.next) |