diff options
| -rw-r--r-- | include/linux/ftrace_event.h | 4 | ||||
| -rw-r--r-- | include/trace/ftrace.h | 9 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 2 | ||||
| -rw-r--r-- | kernel/trace/ring_buffer.c | 42 | ||||
| -rw-r--r-- | kernel/trace/ring_buffer_benchmark.c | 18 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 188 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_branch.c | 1 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_export.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_functions_graph.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_irqsoff.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_nop.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_output.c | 44 | ||||
| -rw-r--r-- | kernel/trace/trace_printk.c | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_sched_switch.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_sched_wakeup.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_stack.c | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_stat.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_uprobe.c | 2 | ||||
| -rw-r--r-- | samples/trace_events/trace-events-sample.c | 80 | ||||
| -rw-r--r-- | samples/trace_events/trace-events-sample.h | 328 |
23 files changed, 582 insertions, 164 deletions
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index d36f68b08acc..c674ee8f7fca 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -44,6 +44,10 @@ const char *ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, const char *ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int len); +const char *ftrace_print_array_seq(struct trace_seq *p, + const void *buf, int buf_len, + size_t el_size); + struct trace_iterator; struct trace_event; diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 27609dfcce25..41bf65f04dd9 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -263,6 +263,14 @@ #undef __print_hex #define __print_hex(buf, buf_len) ftrace_print_hex_seq(p, buf, buf_len) +#undef __print_array +#define __print_array(array, count, el_size) \ + ({ \ + BUILD_BUG_ON(el_size != 1 && el_size != 2 && \ + el_size != 4 && el_size != 8); \ + ftrace_print_array_seq(p, array, count, el_size); \ + }) + #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ static notrace enum print_line_t \ @@ -674,6 +682,7 @@ static inline void ftrace_test_probe_##call(void) \ #undef __get_dynamic_array_len #undef __get_str #undef __get_bitmask +#undef __print_array #undef TP_printk #define TP_printk(fmt, args...) "\"" fmt "\", " __stringify(args) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 224e768bdc73..45e5cb143d17 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5456,7 +5456,7 @@ static __init int ftrace_init_debugfs(void) struct dentry *d_tracer; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; ftrace_init_dyn_debugfs(d_tracer); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 7a4104cb95cb..5040d44fe5a3 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -9,7 +9,6 @@ #include <linux/trace_seq.h> #include <linux/spinlock.h> #include <linux/irq_work.h> -#include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/hardirq.h> #include <linux/kthread.h> /* for self test */ @@ -23,7 +22,6 @@ #include <linux/hash.h> #include <linux/list.h> #include <linux/cpu.h> -#include <linux/fs.h> #include <asm/local.h> @@ -447,7 +445,10 @@ int ring_buffer_print_page_header(struct trace_seq *s) struct rb_irq_work { struct irq_work work; wait_queue_head_t waiters; + wait_queue_head_t full_waiters; bool waiters_pending; + bool full_waiters_pending; + bool wakeup_full; }; /* @@ -529,6 +530,10 @@ static void rb_wake_up_waiters(struct irq_work *work) struct rb_irq_work *rbwork = container_of(work, struct rb_irq_work, work); wake_up_all(&rbwork->waiters); + if (rbwork->wakeup_full) { + rbwork->wakeup_full = false; + wake_up_all(&rbwork->full_waiters); + } } /** @@ -553,9 +558,11 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full) * data in any cpu buffer, or a specific buffer, put the * caller on the appropriate wait queue. */ - if (cpu == RING_BUFFER_ALL_CPUS) + if (cpu == RING_BUFFER_ALL_CPUS) { work = &buffer->irq_work; - else { + /* Full only makes sense on per cpu reads */ + full = false; + } else { if (!cpumask_test_cpu(cpu, buffer->cpumask)) return -ENODEV; cpu_buffer = buffer->buffers[cpu]; @@ -564,7 +571,10 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full) while (true) { - prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE); + if (full) + prepare_to_wait(&work->full_waiters, &wait, TASK_INTERRUPTIBLE); + else + prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE); /* * The events can happen in critical sections where @@ -586,7 +596,10 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full) * that is necessary is that the wake up happens after * a task has been queued. It's OK for spurious wake ups. */ - work->waiters_pending = true; + if (full) + work->full_waiters_pending = true; + else + work->waiters_pending = true; if (signal_pending(current)) { ret = -EINTR; @@ -615,7 +628,10 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full) schedule(); } - finish_wait(&work->waiters, &wait); + if (full) + finish_wait(&work->full_waiters, &wait); + else + finish_wait(&work->waiters, &wait); return ret; } @@ -1230,6 +1246,7 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int nr_pages, int cpu) init_completion(&cpu_buffer->update_done); init_irq_work(&cpu_buffer->irq_work.work, rb_wake_up_waiters); init_waitqueue_head(&cpu_buffer->irq_work.waiters); + init_waitqueue_head(&cpu_buffer->irq_work.full_waiters); bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()), GFP_KERNEL, cpu_to_node(cpu)); @@ -2801,6 +2818,8 @@ static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer, static __always_inline void rb_wakeups(struct ring_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer) { + bool pagebusy; + if (buffer->irq_work.waiters_pending) { buffer->irq_work.waiters_pending = false; /* irq_work_queue() supplies it's own memory barriers */ @@ -2812,6 +2831,15 @@ rb_wakeups(struct ring_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer) /* irq_work_queue() supplies it's own memory barriers */ irq_work_queue(&cpu_buffer->irq_work.work); } + + pagebusy = cpu_buffer->reader_page == cpu_buffer->commit_page; + + if (!pagebusy && cpu_buffer->irq_work.full_waiters_pending) { + cpu_buffer->irq_work.wakeup_full = true; + cpu_buffer->irq_work.full_waiters_pending = false; + /* irq_work_queue() supplies it's own memory barriers */ + irq_work_queue(&cpu_buffer->irq_work.work); + } } /** diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index 3f9e328c30b5..13d945c0d03f 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -7,7 +7,7 @@ #include <linux/completion.h> #include <linux/kthread.h> #include <linux/module.h> -#include <linux/time.h> +#include <linux/ktime.h> #include <asm/local.h> struct rb_page { @@ -17,7 +17,7 @@ struct rb_page { }; /* run time and sleep time in seconds */ -#define RUN_TIME 10 +#define RUN_TIME 10ULL #define SLEEP_TIME 10 /* number of events for writer to wake up the reader */ @@ -212,8 +212,7 @@ static void ring_buffer_consumer(void) static void ring_buffer_producer(void) { - struct timeval start_tv; - struct timeval end_tv; + ktime_t start_time, end_time, timeout; unsigned long long time; unsigned long long entries; unsigned long long overruns; @@ -227,7 +226,8 @@ static void ring_buffer_producer(void) * make the system stall) */ trace_printk("Starting ring buffer hammer\n"); - do_gettimeofday(&start_tv); + start_time = ktime_get(); + timeout = ktime_add_ns(start_time, RUN_TIME * NSEC_PER_SEC); do { struct ring_buffer_event *event; int *entry; @@ -244,7 +244,7 @@ static void ring_buffer_producer(void) ring_buffer_unlock_commit(buffer, event); } } - do_gettimeofday(&end_tv); + end_time = ktime_get(); cnt++; if (consumer && !(cnt % wakeup_interval)) @@ -264,7 +264,7 @@ static void ring_buffer_producer(void) cond_resched(); #endif - } while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test); + } while (ktime_before(end_time, timeout) && !kill_test); trace_printk("End ring buffer hammer\n"); if (consumer) { @@ -280,9 +280,7 @@ static void ring_buffer_producer(void) wait_for_completion(&read_done); } - time = end_tv.tv_sec - start_tv.tv_sec; - time *= USEC_PER_SEC; - time += (long long)((long)end_tv.tv_usec - (long)start_tv.tv_usec); + time = ktime_us_delta(end_time, start_time); entries = ring_buffer_entries(buffer); overruns = ring_buffer_overruns(buffer); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 4a9079b9f082..77b8dc528006 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2036,7 +2036,8 @@ void trace_printk_init_buffers(void) /* trace_printk() is for debug use only. Don't use it in production. */ - pr_warning("\n**********************************************************\n"); + pr_warning("\n"); + pr_warning("**********************************************************\n"); pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); pr_warning("** **\n"); pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); @@ -4140,6 +4141,12 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) goto out; } + /* If trace pipe files are being read, we can't change the tracer */ + if (tr->current_trace->ref) { + ret = -EBUSY; + goto out; + } + trace_branch_disable(); tr->current_trace->enabled--; @@ -4326,17 +4333,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) } trace_seq_init(&iter->seq); - - /* - * We make a copy of the current tracer to avoid concurrent - * changes on it while we are reading. - */ - iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); - if (!iter->trace) { - ret = -ENOMEM; - goto fail; - } - *iter->trace = *tr->current_trace; + iter->trace = tr->current_trace; if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { ret = -ENOMEM; @@ -4363,6 +4360,8 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) iter->trace->pipe_open(iter); nonseekable_open(inode, filp); + + tr->current_trace->ref++; out: mutex_unlock(&trace_types_lock); return ret; @@ -4382,6 +4381,8 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) mutex_lock(&trace_types_lock); + tr->current_trace->ref--; + if (iter->trace->pipe_close) iter->trace->pipe_close(iter); @@ -4389,7 +4390,6 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) free_cpumask_var(iter->started); mutex_destroy(&iter->mutex); - kfree(iter->trace); kfree(iter); trace_array_put(tr); @@ -4422,7 +4422,7 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table) return trace_poll(iter, filp, poll_table); } -/* Must be called with trace_types_lock mutex held. */ +/* Must be called with iter->mutex held. */ static int tracing_wait_pipe(struct file *filp) { struct trace_iterator *iter = filp->private_data; @@ -4467,7 +4467,6 @@ tracing_read_pipe(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_iterator *iter = filp->private_data; - struct trace_array *tr = iter->tr; ssize_t sret; /* return any leftover data */ @@ -4477,12 +4476,6 @@ tracing_read_pipe(struct file *filp, char __user *ubuf, trace_seq_init(&iter->seq); - /* copy the tracer to avoid using a global lock all around */ - mutex_lock(&trace_types_lock); - if (unlikely(iter->trace->name != tr->current_trace->name)) - *iter->trace = *tr->current_trace; - mutex_unlock(&trace_types_lock); - /* * Avoid more than one consumer on a single file descriptor * This is just a matter of traces coherency, the ring buffer itself @@ -4642,7 +4635,6 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, .ops = &tracing_pipe_buf_ops, .spd_release = tracing_spd_release_pipe, }; - struct trace_array *tr = iter->tr; ssize_t ret; size_t rem; unsigned int i; @@ -4650,12 +4642,6 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, if (splice_grow_spd(pipe, &spd)) return -ENOMEM; - /* copy the tracer to avoid using a global lock all around */ - mutex_lock(&trace_types_lock); - if (unlikely(iter->trace->name != tr->current_trace->name)) - *iter->trace = *tr->current_trace; - mutex_unlock(&trace_types_lock); - mutex_lock(&iter->mutex); if (iter->trace->splice_read) { @@ -4942,7 +4928,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, *fpos += written; out_unlock: - for (i = 0; i < nr_pages; i++){ + for (i = nr_pages - 1; i >= 0; i--) { kunmap_atomic(map_page[i]); put_page(pages[i]); } @@ -5331,6 +5317,8 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) filp->private_data = info; + tr->current_trace->ref++; + mutex_unlock(&trace_types_lock); ret = nonseekable_open(inode, filp); @@ -5361,21 +5349,16 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, if (!count) return 0; - mutex_lock(&trace_types_lock); - #ifdef CONFIG_TRACER_MAX_TRACE - if (iter->snapshot && iter->tr->current_trace->use_max_tr) { - size = -EBUSY; - goto out_unlock; - } + if (iter->snapshot && iter->tr->current_trace->use_max_tr) + return -EBUSY; #endif if (!info->spare) info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, iter->cpu_file); - size = -ENOMEM; if (!info->spare) - goto out_unlock; + return -ENOMEM; /* Do we have previous read data to read? */ if (info->read < PAGE_SIZE) @@ -5391,21 +5374,16 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, if (ret < 0) { if (trace_empty(iter)) { - if ((filp->f_flags & O_NONBLOCK)) { - size = -EAGAIN; - goto out_unlock; - } - mutex_unlock(&trace_types_lock); + if ((filp->f_flags & O_NONBLOCK)) + return -EAGAIN; + ret = wait_on_pipe(iter, false); - mutex_lock(&trace_types_lock); - if (ret) { - size = ret; - goto out_unlock; - } + if (ret) + return ret; + goto again; } - size = 0; - goto out_unlock; + return 0; } info->read = 0; @@ -5415,18 +5393,14 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, size = count; ret = copy_to_user(ubuf, info->spare + info->read, size); - if (ret == size) { - size = -EFAULT; - goto out_unlock; - } + if (ret == size) + return -EFAULT; + size -= ret; *ppos += size; info->read += size; - out_unlock: - mutex_unlock(&trace_types_lock); - return size; } @@ -5437,6 +5411,8 @@ static int tracing_buffers_release(struct inode *inode, struct file *file) mutex_lock(&trace_types_lock); + iter->tr->current_trace->ref--; + __trace_array_put(iter->tr); if (info->spare) @@ -5522,30 +5498,20 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, int entries, size, i; ssize_t ret = 0; - mutex_lock(&trace_types_lock); - #ifdef CONFIG_TRACER_MAX_TRACE - if (iter->snapshot && iter->tr->current_trace->use_max_tr) { - ret = -EBUSY; - goto out; - } + if (iter->snapshot && iter->tr->current_trace->use_max_tr) + return -EBUSY; #endif - if (splice_grow_spd(pipe, &spd)) { - ret = -ENOMEM; - goto out; - } + if (splice_grow_spd(pipe, &spd)) + return -ENOMEM; - if (*ppos & (PAGE_SIZE - 1)) { - ret = -EINVAL; - goto out; - } + if (*ppos & (PAGE_SIZE - 1)) + return -EINVAL; if (len & (PAGE_SIZE - 1)) { - if (len < PAGE_SIZE) { - ret = -EINVAL; - goto out; - } + if (len < PAGE_SIZE) + return -EINVAL; len &= PAGE_MASK; } @@ -5606,25 +5572,20 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, /* did we read anything? */ if (!spd.nr_pages) { if (ret) - goto out; + return ret; + + if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) + return -EAGAIN; - if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { - ret = -EAGAIN; - goto out; - } - mutex_unlock(&trace_types_lock); ret = wait_on_pipe(iter, true); - mutex_lock(&trace_types_lock); if (ret) - goto out; + return ret; goto again; } ret = splice_to_pipe(pipe, &spd); splice_shrink_spd(&spd); -out: - mutex_unlock(&trace_types_lock); return ret; } @@ -5854,28 +5815,11 @@ static __init int register_snapshot_cmd(void) static inline __init int register_snapshot_cmd(void) { return 0; } #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ -struct dentry *tracing_init_dentry_tr(struct trace_array *tr) +static struct dentry *tracing_get_dentry(struct trace_array *tr) { - if (tr->dir) - return tr->dir; - - if (!debugfs_initialized()) - return NULL; - - if (tr->flags & TRACE_ARRAY_FL_GLOBAL) - tr->dir = debugfs_create_dir("tracing", NULL); - - if (!tr->dir) - pr_warn_once("Could not create debugfs directory 'tracing'\n"); - return tr->dir; } -struct dentry *tracing_init_dentry(void) -{ - return tracing_init_dentry_tr(&global_trace); -} - static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) { struct dentry *d_tracer; @@ -5883,8 +5827,8 @@ static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) if (tr->percpu_dir) return tr->percpu_dir; - d_tracer = tracing_init_dentry_tr(tr); - if (!d_tracer) + d_tracer = tracing_get_dentry(tr); + if (IS_ERR(d_tracer)) return NULL; tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); @@ -6086,8 +6030,8 @@ static struct dentry *trace_options_init_dentry(struct trace_array *tr) if (tr->options) return tr->options; - d_tracer = tracing_init_dentry_tr(tr); - if (!d_tracer) + d_tracer = tracing_get_dentry(tr); + if (IS_ERR(d_tracer)) return NULL; tr->options = debugfs_create_dir("options", d_tracer); @@ -6416,7 +6360,7 @@ static int instance_delete(const char *name) goto out_unlock; ret = -EBUSY; - if (tr->ref) + if (tr->ref || (tr->current_trace && tr->current_trace->ref)) goto out_unlock; list_del(&tr->list); @@ -6571,6 +6515,33 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) } +/** + * tracing_init_dentry - initialize top level trace array + * + * This is called when creating files or directories in the tracing + * directory. It is called via fs_initcall() by any of the boot up code + * and expects to return the dentry of the top level tracing directory. + */ +struct dentry *tracing_init_dentry(void) +{ + struct trace_array *tr = &global_trace; + + if (tr->dir) + return tr->dir; + + if (WARN_ON(!debugfs_initialized())) + return ERR_PTR(-ENODEV); + + tr->dir = debugfs_create_dir("tracing", NULL); + + if (!tr->dir) { + pr_warn_once("Could not create debugfs directory 'tracing'\n"); + return ERR_PTR(-ENOMEM); + } + + return tr->dir; +} + static __init int tracer_init_debugfs(void) { struct dentry *d_tracer; @@ -6578,7 +6549,7 @@ static __init int tracer_init_debugfs(void) trace_access_lock_init(); d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; init_tracer_debugfs(&global_trace, d_tracer); @@ -6811,7 +6782,6 @@ __init static int tracer_alloc_buffers(void) int ring_buf_size; int ret = -ENOMEM; - if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) goto out; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 8de48bac1ce2..dd8205a35760 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -388,6 +388,7 @@ struct tracer { struct tracer *next; struct tracer_flags *flags; int enabled; + int ref; bool print_max; bool allow_instances; #ifdef CONFIG_TRACER_MAX_TRACE @@ -541,7 +542,6 @@ struct dentry *trace_create_file(const char *name, void *data, const struct file_operations *fops); -struct dentry *tracing_init_dentry_tr(struct trace_array *tr); struct dentry *tracing_init_dentry(void); struct ring_buffer_event; diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index 7d6e2afde669..57cbf1efdd44 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -7,7 +7,6 @@ #include <linux/seq_file.h> #include <linux/spinlock.h> #include <linux/irqflags.h> -#include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/module.h> #include <linux/ftrace.h> diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index b03a0ea77b99..db54dda10ccc 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2531,7 +2531,7 @@ static __init int event_trace_init(void) return -ENODEV; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; entry = debugfs_create_file("available_events", 0444, d_tracer, diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index d4ddde28a81a..12e2b99be862 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -6,12 +6,10 @@ #include <linux/stringify.h> #include <linux/kallsyms.h> #include <linux/seq_file.h> -#include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/ftrace.h> #include <linux/module.h> #include <linux/init.h> -#include <linux/fs.h> #include "trace_output.h" diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index ba476009e5de..2d25ad1526bb 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -1437,7 +1437,7 @@ static __init int init_graph_debugfs(void) struct dentry *d_tracer; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; trace_create_file("max_graph_depth", 0644, d_tracer, diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 9bb104f748d0..8523ea345f2b 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -10,11 +10,9 @@ * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/kallsyms.h> -#include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/module.h> #include <linux/ftrace.h> -#include <linux/fs.h> #include "trace.h" diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 296079ae6583..d73f565b4e06 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1320,7 +1320,7 @@ static __init int init_kprobe_trace(void) return -EINVAL; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; entry = debugfs_create_file("kprobe_events", 0644, d_tracer, diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c index fcf0a9e48916..8bb2071474dd 100644 --- a/kernel/trace/trace_nop.c +++ b/kernel/trace/trace_nop.c @@ -6,8 +6,6 @@ */ #include <linux/module.h> -#include <linux/fs.h> -#include <linux/debugfs.h> #include <linux/ftrace.h> #include "trace.h" diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index b77b9a697619..692bf7184c8c 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -177,6 +177,50 @@ ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len) } EXPORT_SYMBOL(ftrace_print_hex_seq); +const char * +ftrace_print_array_seq(struct trace_seq *p, const void *buf, int buf_len, + size_t el_size) +{ + const char *ret = trace_seq_buffer_ptr(p); + const char *prefix = ""; + void *ptr = (void *)buf; + + trace_seq_putc(p, '{'); + + while (ptr < buf + buf_len) { + switch (el_size) { + case 1: + trace_seq_printf(p, "%s0x%x", prefix, + *(u8 *)ptr); + break; + case 2: + trace_seq_printf(p, "%s0x%x", prefix, + *(u16 *)ptr); + break; + case 4: + trace_seq_printf(p, "%s0x%x", prefix, + *(u32 *)ptr); + break; + case 8: + trace_seq_printf(p, "%s0x%llx", prefix, + *(u64 *)ptr); + break; + default: + trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size, + *(u8 *)ptr); + el_size = 1; + } + prefix = ","; + ptr += el_size; + } + + trace_seq_putc(p, '}'); + trace_seq_putc(p, 0); + + return ret; +} +EXPORT_SYMBOL(ftrace_print_array_seq); + int ftrace_raw_output_prep(struct trace_iterator *iter, struct trace_event *trace_event) { diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index c4e70b6bd7fa..36c1455b7567 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -5,7 +5,6 @@ * */ #include <linux/seq_file.h> -#include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/kernel.h> #include <linux/ftrace.h> @@ -15,7 +14,6 @@ #include <linux/ctype.h> #include <linux/list.h> #include <linux/slab.h> -#include <linux/fs.h> #include "trace.h" @@ -349,7 +347,7 @@ static __init int init_trace_printk_function_export(void) struct dentry *d_tracer; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; trace_create_file("printk_formats", 0444, d_tracer, diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index 2e293beb186e..419ca37e72c9 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -5,8 +5,6 @@ * */ #include <linux/module.h> -#include <linux/fs.h> -#include <linux/debugfs.h> #include <linux/kallsyms.h> #include <linux/uaccess.h> #include <linux/ftrace.h> diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 8fb84b362816..d6e1003724e9 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -10,8 +10,6 @@ * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/module.h> -#include <linux/fs.h> -#include <linux/debugfs.h> #include <linux/kallsyms.h> #include <linux/uaccess.h> #include <linux/ftrace.h> diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 16eddb308c33..c3e4fcfddd45 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -7,12 +7,10 @@ #include <linux/seq_file.h> #include <linux/spinlock.h> #include <linux/uaccess.h> -#include <linux/debugfs.h> #include <linux/ftrace.h> #include <linux/module.h> #include <linux/sysctl.h> #include <linux/init.h> -#include <linux/fs.h> #include <asm/setup.h> @@ -462,7 +460,7 @@ static __init int stack_trace_init(void) struct dentry *d_tracer; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; trace_create_file("stack_max_size", 0644, d_tracer, diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index 7af67360b330..75e19e86c954 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -276,7 +276,7 @@ static int tracing_stat_init(void) struct dentry *d_tracing; d_tracing = tracing_init_dentry(); - if (!d_tracing) + if (IS_ERR(d_tracing)) return 0; stat_dir = debugfs_create_dir("trace_stat", d_tracing); diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index b11441321e7a..7dc1c8abecd6 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -1321,7 +1321,7 @@ static __init int init_uprobe_trace(void) struct dentry *d_tracer; d_tracer = tracing_init_dentry(); - if (!d_tracer) + if (IS_ERR(d_tracer)) return 0; trace_create_file("uprobe_events", 0644, d_tracer, diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c index aabc4e970911..880a7d1d27d2 100644 --- a/samples/trace_events/trace-events-sample.c +++ b/samples/trace_events/trace-events-sample.c @@ -10,12 +10,38 @@ #define CREATE_TRACE_POINTS #include "trace-events-sample.h" +static const char *random_strings[] = { + "Mother Goose", + "Snoopy", + "Gandalf", + "Frodo", + "One ring to rule them all" +}; static void simple_thread_func(int cnt) { + int array[6]; + int len = cnt % 5; + int i; + set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(HZ); - trace_foo_bar("hello", cnt); + + for (i = 0; i < len; i++) + array[i] = i + 1; + array[i] = 0; + + /* Silly tracepoints */ + trace_foo_bar("hello", cnt, array, random_strings[len], + tsk_cpus_allowed(current)); + + trace_foo_with_template_simple("HELLO", cnt); + + trace_foo_bar_with_cond("Some times print", cnt); + + trace_foo_with_template_cond("prints other times", cnt); + + trace_foo_with_template_print("I have to be different", cnt); } static int simple_thread(void *arg) @@ -29,6 +55,53 @@ static int simple_thread(void *arg) } static struct task_struct *simple_tsk; +static struct task_struct *simple_tsk_fn; + +static void simple_thread_func_fn(int cnt) +{ + set_current_state(TASK_INTERRUPTIBLE); + schedule_timeout(HZ); + + /* More silly tracepoints */ + trace_foo_bar_with_fn("Look at me", cnt); + trace_foo_with_template_fn("Look at me too", cnt); +} + +static int simple_thread_fn(void *arg) +{ + int cnt = 0; + + while (!kthread_should_stop()) + simple_thread_func_fn(cnt++); + + return 0; +} + +static DEFINE_MUTEX(thread_mutex); + +void foo_bar_reg(void) +{ + pr_info("Starting thread for foo_bar_fn\n"); + /* + * We shouldn't be able to start a trace when the module is + * unloading (there's other locks to prevent that). But + * for consistency sake, we still take the thread_mutex. + */ + mutex_lock(&thread_mutex); + simple_tsk_fn = kthread_run(simple_thread_fn, NULL, "event-sample-fn"); + mutex_unlock(&thread_mutex); +} + +void foo_bar_unreg(void) +{ + pr_info("Killing thread for foo_bar_fn\n"); + /* protect against module unloading */ + mutex_lock(&thread_mutex); + if (simple_tsk_fn) + kthread_stop(simple_tsk_fn); + simple_tsk_fn = NULL; + mutex_unlock(&thread_mutex); +} static int __init trace_event_init(void) { @@ -42,6 +115,11 @@ static int __init trace_event_init(void) static void __exit trace_event_exit(void) { kthread_stop(simple_tsk); + mutex_lock(&thread_mutex); + if (simple_tsk_fn) + kthread_stop(simple_tsk_fn); + simple_tsk_fn = NULL; + mutex_unlock(&thread_mutex); } module_init(trace_event_init); diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h index 476429281389..a2c8b02b6359 100644 --- a/samples/trace_events/trace-events-sample.h +++ b/samples/trace_events/trace-events-sample.h @@ -1,6 +1,6 @@ /* * If TRACE_SYSTEM is defined, that will be the directory created - * in the ftrace directory under /sys/kernel/debug/tracing/events/<system> + * in the ftrace directory under /sys/kernel/tracing/events/<system> * * The define_trace.h below will also look for a file name of * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here. @@ -54,45 +54,347 @@ * Here it is simply "foo, bar". * * struct: This defines the way the data will be stored in the ring buffer. - * There are currently two types of elements. __field and __array. - * a __field is broken up into (type, name). Where type can be any - * primitive type (integer, long or pointer). __field_struct() can - * be any static complex data value (struct, union, but not an array). - * For an array. there are three fields. (type, name, size). The - * type of elements in the array, the name of the field and the size - * of the array. + * The items declared here become part of a special structure + * called "__entry", which can be used in the fast_assign part of the + * TRACE_EVENT macro. + * + * Here are the currently defined types you can use: + * + * __field : Is broken up into type and name. Where type can be any + * primitive type (integer, long or pointer). + * + * __field(int, foo) + * + * __entry->foo = 5; + * + * __field_struct : This can be any static complex data type (struct, union + * but not an array). Be careful using complex types, as each + * event is limited in size, and copying large amounts of data + * into the ring buffer can slow things down. + * + * __field_struct(struct bar, foo) + * + * __entry->bar.x = y; + + * __array: There are three fields (type, name, size). The type is the + * type of elements in teh array, the name is the name of the array. + * size is the number of items in the array (not the total size). + * + * __array( char, foo, 10) is the same as saying: char foo[10]; + * + * Assigning arrays can be done like any array: + * + * __entry->foo[0] = 'a'; + * + * memcpy(__entry->foo, bar, 10); + * + * __dynamic_array: This is similar to array, but can vary is size from + * instance to instance of the tracepoint being called. + * Like __array, this too has three elements (type, name, size); + * type is the type of the element, name is the name of the array. + * The size is different than __array. It is not a static number, + * but the algorithm to figure out the length of the array for the + * specific instance of tracepoint. Again, size is the numebr of + * items in the array, not the total length in bytes. + * + * __dynamic_array( int, foo, bar) is similar to: int foo[bar]; + * + * Note, unlike arrays, you must use the __get_dynamic_array() macro + * to access the array. + * + * memcpy(__get_dynamic_array(foo), bar, 10); + * + * Notice, that "__entry" is not needed here. + * + * __string: This is a special kind of __dynamic_array. It expects to + * have a nul terminated character array passed to it (it allows + * for NULL too, which would be converted into "(null)"). __string + * takes two paramenter (name, src), where name is the name of + * the string saved, and src is the string to copy into the + * ring buffer. + * + * __string(foo, bar) is similar to: strcpy(foo, bar) + * + * To assign a string, use the helper macro __assign_str(). + * + * __assign_str(foo, bar); + * + * In most cases, the __assign_str() macro will take the same + * parameters as the __string() macro had to declare the string. + * + * __bitmask: This is another kind of __dynamic_array, but it expects + * an array of longs, and the number of bits to parse. It takes + * two parameters (name, nr_bits), where name is the name of the + * bitmask to save, and the nr_bits is the number of bits to record. + * + * __bitmask(target_cpu, nr_cpumask_bits) + * + * To assign a bitmask, use the __assign_bitmask() helper macro. + * + * __assign_bitmask(target_cpus, cpumask_bits(bar), nr_cpumask_bits); * - * __array( char, foo, 10) is the same as saying char foo[10]. * * fast_assign: This is a C like function that is used to store the items - * into the ring buffer. + * into the ring buffer. A special variable called "__entry" will be the + * structure that points into the ring buffer and has the same fields as + * described by the struct part of TRACE_EVENT above. * * printk: This is a way to print out the data in pretty print. This is * useful if the system crashes and you are logging via a serial line, * the data can be printed to the console using this "printk" method. + * This is also used to print out the data from the trace files. + * Again, the __entry macro is used to access the data from the ring buffer. + * + * Note, __dynamic_array, __string, and __bitmask require special helpers + * to access the data. + * + * For __dynamic_array(int, foo, bar) use __get_dynamic_array(foo) + * Use __get_dynamic_array_len(foo) to get the length of the array + * saved. + * + * For __string(foo, bar) use __get_str(foo) + * + * For __bitmask(target_cpus, nr_cpumask_bits) use __get_bitmask(target_cpus) + * * * Note, that for both the assign and the printk, __entry is the handler * to the data structure in the ring buffer, and is defined by the * TP_STRUCT__entry. */ + +/* + * It is OK to have helper functions in the file, but they need to be protected + * from being defined more than once. Remember, this file gets included more + * than once. + */ +#ifndef __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS +#define __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS +static inline int __length_of(const int *list) +{ + int i; + + if (!list) + return 0; + + for (i = 0; list[i]; i++) + ; + return i; +} +#endif + TRACE_EVENT(foo_bar, - TP_PROTO(char *foo, int bar), + TP_PROTO(const char *foo, int bar, const int *lst, + const char *string, const struct cpumask *mask), - TP_ARGS(foo, bar), + TP_ARGS(foo, bar, lst, string, mask), TP_STRUCT__entry( __array( char, foo, 10 ) __field( int, bar ) + __dynamic_array(int, list, __length_of(lst)) + __string( str, string ) + __bitmask( cpus, num_possible_cpus() ) ), TP_fast_assign( strlcpy(__entry->foo, foo, 10); __entry->bar = bar; + memcpy(__get_dynamic_array(list), lst, + __length_of(lst) * sizeof(int)); + __assign_str(str, string); + __assign_bitmask(cpus, cpumask_bits(mask), num_possible_cpus()); + ), + + TP_printk("foo %s %d %s %s (%s)", __entry->foo, __entry->bar, + __print_array(__get_dynamic_array(list), + __get_dynamic_array_len(list), + sizeof(int)), + __get_str(str), __get_bitmask(cpus)) +); + +/* + * There may be a case where a tracepoint should only be called if + * some condition is set. Otherwise the tracepoint should not be called. + * But to do something like: + * + * if (cond) + * trace_foo(); + * + * Would cause a little overhead when tracing is not enabled, and that + * overhead, even if small, is not something we want. As tracepoints + * use static branch (aka jump_labels), where no branch is taken to + * skip the tracepoint when not enabled, and a jmp is placed to jump + * to the tracepoint code when it is enabled, having a if statement + * nullifies that optimization. It would be nice to place that + * condition within the static branch. This is where TRACE_EVENT_CONDITION + * comes in. + * + * TRACE_EVENT_CONDITION() is just like TRACE_EVENT, except it adds another + * parameter just after args. Where TRACE_EVENT has: + * + * TRACE_EVENT(name, proto, args, struct, assign, printk) + * + * the CONDITION version has: + * + * TRACE_EVENT_CONDITION(name, proto, args, cond, struct, assign, printk) + * + * Everything is the same as TRACE_EVENT except for the new cond. Think + * of the cond variable as: + * + * if (cond) + * trace_foo_bar_with_cond(); + * + * Except that the logic for the if branch is placed after the static branch. + * That is, the if statement that processes the condition will not be + * executed unless that traecpoint is enabled. Otherwise it still remains + * a nop. + */ +TRACE_EVENT_CONDITION(foo_bar_with_cond, + + TP_PROTO(const char *foo, int bar), + + TP_ARGS(foo, bar), + + TP_CONDITION(!(bar % 10)), + + TP_STRUCT__entry( + __string( foo, foo ) + __field( int, bar ) + ), + + TP_fast_assign( + __assign_str(foo, foo); + __entry->bar = bar; + ), + + TP_printk("foo %s %d", __get_str(foo), __entry->bar) +); + +void foo_bar_reg(void); +void foo_bar_unreg(void); + +/* + * Now in the case that some function needs to be called when the + * tracepoint is enabled and/or when it is disabled, the + * TRACE_EVENT_FN() serves this purpose. This is just like TRACE_EVENT() + * but adds two more parameters at the end: + * + * TRACE_EVENT_FN( name, proto, args, struct, assign, printk, reg, unreg) + * + * reg and unreg are functions with the prototype of: + * + * void reg(void) + * + * The reg function gets called before the tracepoint is enabled, and + * the unreg function gets called after the tracepoint is disabled. + * + * Note, reg and unreg are allowed to be NULL. If you only need to + * call a function before enabling, or after disabling, just set one + * function and pass in NULL for the other parameter. + */ +TRACE_EVENT_FN(foo_bar_with_fn, + + TP_PROTO(const char *foo, int bar), + + TP_ARGS(foo, bar), + + TP_STRUCT__entry( + __string( foo, foo ) + __field( int, bar ) + ), + + TP_fast_assign( + __assign_str(foo, foo); + __entry->bar = bar; + ), + + TP_printk("foo %s %d", __get_str(foo), __entry->bar), + + foo_bar_reg, foo_bar_unreg +); + +/* + * Each TRACE_EVENT macro creates several helper functions to produce + * the code to add the tracepoint, create the files in the trace + * directory, hook it to perf, assign the values and to print out + * the raw data from the ring buffer. To prevent too much bloat, + * if there are more than one tracepoint that uses the same format + * for the proto, args, struct, assign and printk, and only the name + * is different, it is highly recommended to use the DECLARE_EVENT_CLASS + * + * DECLARE_EVENT_CLASS() macro creates most of the functions for the + * tracepoint. Then DEFINE_EVENT() is use to hook a tracepoint to those + * functions. This DEFINE_EVENT() is an instance of the class and can + * be enabled and disabled separately from other events (either TRACE_EVENT + * or other DEFINE_EVENT()s). + * + * Note, TRACE_EVENT() itself is simply defined as: + * + * #define TRACE_EVENT(name, proto, args, tstruct, assign, printk) \ + * DEFINE_EVENT_CLASS(name, proto, args, tstruct, assign, printk); \ + * DEFINE_EVENT(name, name, proto, args) + * + * The DEFINE_EVENT() also can be declared with conditions and reg functions: + * + * DEFINE_EVENT_CONDITION(template, name, proto, args, cond); + * DEFINE_EVENT_FN(template, name, proto, args, reg, unreg); + */ +DECLARE_EVENT_CLASS(foo_template, + + TP_PROTO(const char *foo, int bar), + + TP_ARGS(foo, bar), + + TP_STRUCT__entry( + __string( foo, foo ) + __field( int, bar ) + ), + + TP_fast_assign( + __assign_str(foo, foo); + __entry->bar = bar; ), - TP_printk("foo %s %d", __entry->foo, __entry->bar) + TP_printk("foo %s %d", __get_str(foo), __entry->bar) ); + +/* + * Here's a better way for the previous samples (except, the first + * exmaple had more fields and could not be used here). + */ +DEFINE_EVENT(foo_template, foo_with_template_simple, + TP_PROTO(const char *foo, int bar), + TP_ARGS(foo, bar)); + +DEFINE_EVENT_CONDITION(foo_template, foo_with_template_cond, + TP_PROTO(const char *foo, int bar), + TP_ARGS(foo, bar), + TP_CONDITION(!(bar % 8))); + + +DEFINE_EVENT_FN(foo_template, foo_with_template_fn, + TP_PROTO(const char *foo, int bar), + TP_ARGS(foo, bar), + foo_bar_reg, foo_bar_unreg); + +/* + * Anytime two events share basically the same values and have + * the same output, use the DECLARE_EVENT_CLASS() and DEFINE_EVENT() + * when ever possible. + */ + +/* + * If the event is similar to the DECLARE_EVENT_CLASS, but you need + * to have a different output, then use DEFINE_EVENT_PRINT() which + * lets you override the TP_printk() of the class. + */ + +DEFINE_EVENT_PRINT(foo_template, foo_with_template_print, + TP_PROTO(const char *foo, int bar), + TP_ARGS(foo, bar), + TP_printk("bar %s %d", __get_str(foo), __entry->bar)); + #endif /***** NOTICE! The #if protection ends here. *****/ |