#include <linux/fs.h>
#include <linux/kprobes.h>
#include <linux/writeback.h>
+#include <linux/splice.h>
#include <linux/stacktrace.h>
#include <linux/ring_buffer.h>
return cnt;
}
+ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
+{
+ int len;
+ void *ret;
+
+ if (s->len <= s->readpos)
+ return -EBUSY;
+
+ len = s->len - s->readpos;
+ if (cnt > len)
+ cnt = len;
+ ret = memcpy(buf, s->buffer + s->readpos, cnt);
+ if (!ret)
+ return -EFAULT;
+
+ s->readpos += len;
+ return cnt;
+}
+
static void
trace_print_seq(struct seq_file *m, struct trace_seq *s)
{
tracing_selftest_running = false;
mutex_unlock(&trace_types_lock);
- if (!ret && default_bootup_tracer) {
- if (!strncmp(default_bootup_tracer, type->name,
- BOOTUP_TRACER_SIZE)) {
- printk(KERN_INFO "Starting tracer '%s'\n",
- type->name);
- /* Do we want this tracer to start on bootup? */
- tracing_set_tracer(type->name);
- default_bootup_tracer = NULL;
- /* disable other selftests, since this will break it. */
- tracing_selftest_disabled = 1;
+ if (ret || !default_bootup_tracer)
+ goto out_unlock;
+
+ if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE))
+ goto out_unlock;
+
+ printk(KERN_INFO "Starting tracer '%s'\n", type->name);
+ /* Do we want this tracer to start on bootup? */
+ tracing_set_tracer(type->name);
+ default_bootup_tracer = NULL;
+ /* disable other selftests, since this will break it. */
+ tracing_selftest_disabled = 1;
#ifdef CONFIG_FTRACE_STARTUP_TEST
- printk(KERN_INFO "Disabling FTRACE selftests due"
- " to running tracer '%s'\n", type->name);
+ printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n",
+ type->name);
#endif
- }
- }
+ out_unlock:
lock_kernel();
return ret;
}
found:
*t = (*t)->next;
+
+ if (type == current_trace && tracer_enabled) {
+ tracer_enabled = 0;
+ tracing_stop();
+ if (current_trace->stop)
+ current_trace->stop(&global_trace);
+ current_trace = &nop_trace;
+ }
+
if (strlen(type->name) != max_tracer_type_len)
goto out;
(need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
}
+struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
+ unsigned char type,
+ unsigned long len,
+ unsigned long flags, int pc)
+{
+ struct ring_buffer_event *event;
+
+ event = ring_buffer_lock_reserve(tr->buffer, len);
+ if (event != NULL) {
+ struct trace_entry *ent = ring_buffer_event_data(event);
+
+ tracing_generic_entry_update(ent, flags, pc);
+ ent->type = type;
+ }
+
+ return event;
+}
+static void ftrace_trace_stack(struct trace_array *tr,
+ unsigned long flags, int skip, int pc);
+static void ftrace_trace_userstack(struct trace_array *tr,
+ unsigned long flags, int pc);
+
+void trace_buffer_unlock_commit(struct trace_array *tr,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc)
+{
+ ring_buffer_unlock_commit(tr->buffer, event);
+
+ ftrace_trace_stack(tr, flags, 6, pc);
+ ftrace_trace_userstack(tr, flags, pc);
+ trace_wake_up();
+}
+
void
-trace_function(struct trace_array *tr, struct trace_array_cpu *data,
+trace_function(struct trace_array *tr,
unsigned long ip, unsigned long parent_ip, unsigned long flags,
int pc)
{
struct ring_buffer_event *event;
struct ftrace_entry *entry;
- unsigned long irq_flags;
/* If we are reading the ring buffer, don't trace */
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
return;
- event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry),
+ flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_FN;
entry->ip = ip;
entry->parent_ip = parent_ip;
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+ ring_buffer_unlock_commit(tr->buffer, event);
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static void __trace_graph_entry(struct trace_array *tr,
- struct trace_array_cpu *data,
struct ftrace_graph_ent *trace,
unsigned long flags,
int pc)
{
struct ring_buffer_event *event;
struct ftrace_graph_ent_entry *entry;
- unsigned long irq_flags;
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
return;
- event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
+ sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_GRAPH_ENT;
entry->graph_ent = *trace;
- ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags);
+ ring_buffer_unlock_commit(global_trace.buffer, event);
}
static void __trace_graph_return(struct trace_array *tr,
- struct trace_array_cpu *data,
struct ftrace_graph_ret *trace,
unsigned long flags,
int pc)
{
struct ring_buffer_event *event;
struct ftrace_graph_ret_entry *entry;
- unsigned long irq_flags;
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
return;
- event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET,
+ sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_GRAPH_RET;
entry->ret = *trace;
- ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags);
+ ring_buffer_unlock_commit(global_trace.buffer, event);
}
#endif
int pc)
{
if (likely(!atomic_read(&data->disabled)))
- trace_function(tr, data, ip, parent_ip, flags, pc);
+ trace_function(tr, ip, parent_ip, flags, pc);
}
static void __ftrace_trace_stack(struct trace_array *tr,
- struct trace_array_cpu *data,
unsigned long flags,
int skip, int pc)
{
struct ring_buffer_event *event;
struct stack_entry *entry;
struct stack_trace trace;
- unsigned long irq_flags;
- event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_STACK,
+ sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_STACK;
-
memset(&entry->caller, 0, sizeof(entry->caller));
trace.nr_entries = 0;
trace.entries = entry->caller;
save_stack_trace(&trace);
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+ ring_buffer_unlock_commit(tr->buffer, event);
#endif
}
static void ftrace_trace_stack(struct trace_array *tr,
- struct trace_array_cpu *data,
unsigned long flags,
int skip, int pc)
{
if (!(trace_flags & TRACE_ITER_STACKTRACE))
return;
- __ftrace_trace_stack(tr, data, flags, skip, pc);
+ __ftrace_trace_stack(tr, flags, skip, pc);
}
void __trace_stack(struct trace_array *tr,
- struct trace_array_cpu *data,
unsigned long flags,
int skip, int pc)
{
- __ftrace_trace_stack(tr, data, flags, skip, pc);
+ __ftrace_trace_stack(tr, flags, skip, pc);
}
static void ftrace_trace_userstack(struct trace_array *tr,
- struct trace_array_cpu *data,
- unsigned long flags, int pc)
+ unsigned long flags, int pc)
{
#ifdef CONFIG_STACKTRACE
struct ring_buffer_event *event;
struct userstack_entry *entry;
struct stack_trace trace;
- unsigned long irq_flags;
if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
return;
- event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK,
+ sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_USER_STACK;
memset(&entry->caller, 0, sizeof(entry->caller));
trace.entries = entry->caller;
save_stack_trace_user(&trace);
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+ ring_buffer_unlock_commit(tr->buffer, event);
#endif
}
-void __trace_userstack(struct trace_array *tr,
- struct trace_array_cpu *data,
- unsigned long flags)
+void __trace_userstack(struct trace_array *tr, unsigned long flags)
{
- ftrace_trace_userstack(tr, data, flags, preempt_count());
+ ftrace_trace_userstack(tr, flags, preempt_count());
}
static void
-ftrace_trace_special(void *__tr, void *__data,
+ftrace_trace_special(void *__tr,
unsigned long arg1, unsigned long arg2, unsigned long arg3,
int pc)
{
struct ring_buffer_event *event;
- struct trace_array_cpu *data = __data;
struct trace_array *tr = __tr;
struct special_entry *entry;
- unsigned long irq_flags;
- event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL,
+ sizeof(*entry), 0, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, 0, pc);
- entry->ent.type = TRACE_SPECIAL;
entry->arg1 = arg1;
entry->arg2 = arg2;
entry->arg3 = arg3;
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
- ftrace_trace_stack(tr, data, irq_flags, 4, pc);
- ftrace_trace_userstack(tr, data, irq_flags, pc);
-
- trace_wake_up();
+ trace_buffer_unlock_commit(tr, event, 0, pc);
}
void
__trace_special(void *__tr, void *__data,
unsigned long arg1, unsigned long arg2, unsigned long arg3)
{
- ftrace_trace_special(__tr, __data, arg1, arg2, arg3, preempt_count());
+ ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count());
}
void
tracing_sched_switch_trace(struct trace_array *tr,
- struct trace_array_cpu *data,
struct task_struct *prev,
struct task_struct *next,
unsigned long flags, int pc)
{
struct ring_buffer_event *event;
struct ctx_switch_entry *entry;
- unsigned long irq_flags;
- event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_CTX,
+ sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_CTX;
entry->prev_pid = prev->pid;
entry->prev_prio = prev->prio;
entry->prev_state = prev->state;
entry->next_prio = next->prio;
entry->next_state = next->state;
entry->next_cpu = task_cpu(next);
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
- ftrace_trace_stack(tr, data, flags, 5, pc);
- ftrace_trace_userstack(tr, data, flags, pc);
+ trace_buffer_unlock_commit(tr, event, flags, pc);
}
void
tracing_sched_wakeup_trace(struct trace_array *tr,
- struct trace_array_cpu *data,
struct task_struct *wakee,
struct task_struct *curr,
unsigned long flags, int pc)
{
struct ring_buffer_event *event;
struct ctx_switch_entry *entry;
- unsigned long irq_flags;
- event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
- &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_WAKE,
+ sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_WAKE;
entry->prev_pid = curr->pid;
entry->prev_prio = curr->prio;
entry->prev_state = curr->state;
entry->next_prio = wakee->prio;
entry->next_state = wakee->state;
entry->next_cpu = task_cpu(wakee);
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
- ftrace_trace_stack(tr, data, flags, 6, pc);
- ftrace_trace_userstack(tr, data, flags, pc);
-
- trace_wake_up();
+ trace_buffer_unlock_commit(tr, event, flags, pc);
}
void
data = tr->data[cpu];
if (likely(atomic_inc_return(&data->disabled) == 1))
- ftrace_trace_special(tr, data, arg1, arg2, arg3, pc);
+ ftrace_trace_special(tr, arg1, arg2, arg3, pc);
atomic_dec(&data->disabled);
local_irq_restore(flags);
disabled = atomic_inc_return(&data->disabled);
if (likely(disabled == 1)) {
pc = preempt_count();
- __trace_graph_entry(tr, data, trace, flags, pc);
+ __trace_graph_entry(tr, trace, flags, pc);
}
/* Only do the atomic if it is not already set */
if (!test_tsk_trace_graph(current))
disabled = atomic_inc_return(&data->disabled);
if (likely(disabled == 1)) {
pc = preempt_count();
- __trace_graph_return(tr, data, trace, flags, pc);
+ __trace_graph_return(tr, trace, flags, pc);
}
if (!trace->depth)
clear_tsk_trace_graph(current);
goto partial;
}
- if (event && event->latency_trace)
+ if (event)
return event->latency_trace(iter, sym_flags);
if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
goto partial;
}
- if (event && event->trace)
+ if (event)
return event->trace(iter, sym_flags);
if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
}
event = ftrace_find_event(entry->type);
- if (event && event->raw)
+ if (event)
return event->raw(iter, 0);
if (!trace_seq_printf(s, "%d ?\n", entry->type))
}
event = ftrace_find_event(entry->type);
- if (event && event->hex) {
- int ret = event->hex(iter, 0);
+ if (event) {
+ enum print_line_t ret = event->hex(iter, 0);
if (ret != TRACE_TYPE_HANDLED)
return ret;
}
if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
SEQ_PUT_FIELD_RET(s, entry->pid);
- SEQ_PUT_FIELD_RET(s, entry->cpu);
+ SEQ_PUT_FIELD_RET(s, iter->cpu);
SEQ_PUT_FIELD_RET(s, iter->ts);
}
event = ftrace_find_event(entry->type);
- if (event && event->binary)
- return event->binary(iter, 0);
-
- return TRACE_TYPE_HANDLED;
+ return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
}
static int trace_empty(struct trace_iterator *iter)
struct tracer_opt *trace_opts = current_trace->flags->opts;
- /* calulate max size */
+ /* calculate max size */
for (i = 0; trace_options[i]; i++) {
len += strlen(trace_options[i]);
len += 3; /* "no" and space */
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
+int tracer_init(struct tracer *t, struct trace_array *tr)
+{
+ tracing_reset_online_cpus(tr);
+ return t->init(tr);
+}
+
static int tracing_set_tracer(const char *buf)
{
struct trace_array *tr = &global_trace;
current_trace = t;
if (t->init) {
- ret = t->init(tr);
+ ret = tracer_init(t, tr);
if (ret)
goto out;
}
}
}
-/*
- * Consumer reader.
- */
-static ssize_t
-tracing_read_pipe(struct file *filp, char __user *ubuf,
- size_t cnt, loff_t *ppos)
+/* Must be called with trace_types_lock mutex held. */
+static int tracing_wait_pipe(struct file *filp)
{
struct trace_iterator *iter = filp->private_data;
- ssize_t sret;
-
- /* return any leftover data */
- sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
- if (sret != -EBUSY)
- return sret;
-
- trace_seq_reset(&iter->seq);
-
- mutex_lock(&trace_types_lock);
- if (iter->trace->read) {
- sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
- if (sret)
- goto out;
- }
-waitagain:
- sret = 0;
while (trace_empty(iter)) {
if ((filp->f_flags & O_NONBLOCK)) {
- sret = -EAGAIN;
- goto out;
+ return -EAGAIN;
}
/*
iter->tr->waiter = NULL;
if (signal_pending(current)) {
- sret = -EINTR;
- goto out;
+ return -EINTR;
}
if (iter->trace != current_trace)
- goto out;
+ return 0;
/*
* We block until we read something and tracing is disabled.
continue;
}
+ return 1;
+}
+
+/*
+ * Consumer reader.
+ */
+static ssize_t
+tracing_read_pipe(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_iterator *iter = filp->private_data;
+ ssize_t sret;
+
+ /* return any leftover data */
+ sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
+ if (sret != -EBUSY)
+ return sret;
+
+ trace_seq_reset(&iter->seq);
+
+ mutex_lock(&trace_types_lock);
+ if (iter->trace->read) {
+ sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
+ if (sret)
+ goto out;
+ }
+
+waitagain:
+ sret = tracing_wait_pipe(filp);
+ if (sret <= 0)
+ goto out;
+
/* stop when tracing is finished */
- if (trace_empty(iter))
+ if (trace_empty(iter)) {
+ sret = 0;
goto out;
+ }
if (cnt >= PAGE_SIZE)
cnt = PAGE_SIZE - 1;
iter->seq.len = len;
break;
}
-
- trace_consume(iter);
+ if (ret != TRACE_TYPE_NO_CONSUME)
+ trace_consume(iter);
if (iter->seq.len >= cnt)
break;
return sret;
}
+static void tracing_pipe_buf_release(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ __free_page(buf->page);
+}
+
+static void tracing_spd_release_pipe(struct splice_pipe_desc *spd,
+ unsigned int idx)
+{
+ __free_page(spd->pages[idx]);
+}
+
+static struct pipe_buf_operations tracing_pipe_buf_ops = {
+ .can_merge = 0,
+ .map = generic_pipe_buf_map,
+ .unmap = generic_pipe_buf_unmap,
+ .confirm = generic_pipe_buf_confirm,
+ .release = tracing_pipe_buf_release,
+ .steal = generic_pipe_buf_steal,
+ .get = generic_pipe_buf_get,
+};
+
+static size_t
+tracing_fill_pipe_page(struct page *pages, size_t rem,
+ struct trace_iterator *iter)
+{
+ size_t count;
+ int ret;
+
+ /* Seq buffer is page-sized, exactly what we need. */
+ for (;;) {
+ count = iter->seq.len;
+ ret = print_trace_line(iter);
+ count = iter->seq.len - count;
+ if (rem < count) {
+ rem = 0;
+ iter->seq.len -= count;
+ break;
+ }
+ if (ret == TRACE_TYPE_PARTIAL_LINE) {
+ iter->seq.len -= count;
+ break;
+ }
+
+ trace_consume(iter);
+ rem -= count;
+ if (!find_next_entry_inc(iter)) {
+ rem = 0;
+ iter->ent = NULL;
+ break;
+ }
+ }
+
+ return rem;
+}
+
+static ssize_t tracing_splice_read_pipe(struct file *filp,
+ loff_t *ppos,
+ struct pipe_inode_info *pipe,
+ size_t len,
+ unsigned int flags)
+{
+ struct page *pages[PIPE_BUFFERS];
+ struct partial_page partial[PIPE_BUFFERS];
+ struct trace_iterator *iter = filp->private_data;
+ struct splice_pipe_desc spd = {
+ .pages = pages,
+ .partial = partial,
+ .nr_pages = 0, /* This gets updated below. */
+ .flags = flags,
+ .ops = &tracing_pipe_buf_ops,
+ .spd_release = tracing_spd_release_pipe,
+ };
+ ssize_t ret;
+ size_t rem;
+ unsigned int i;
+
+ mutex_lock(&trace_types_lock);
+
+ if (iter->trace->splice_read) {
+ ret = iter->trace->splice_read(iter, filp,
+ ppos, pipe, len, flags);
+ if (ret)
+ goto out_err;
+ }
+
+ ret = tracing_wait_pipe(filp);
+ if (ret <= 0)
+ goto out_err;
+
+ if (!iter->ent && !find_next_entry_inc(iter)) {
+ ret = -EFAULT;
+ goto out_err;
+ }
+
+ /* Fill as many pages as possible. */
+ for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) {
+ pages[i] = alloc_page(GFP_KERNEL);
+ if (!pages[i])
+ break;
+
+ rem = tracing_fill_pipe_page(pages[i], rem, iter);
+
+ /* Copy the data into the page, so we can start over. */
+ ret = trace_seq_to_buffer(&iter->seq,
+ page_address(pages[i]),
+ iter->seq.len);
+ if (ret < 0) {
+ __free_page(pages[i]);
+ break;
+ }
+ partial[i].offset = 0;
+ partial[i].len = iter->seq.len;
+
+ trace_seq_reset(&iter->seq);
+ }
+
+ mutex_unlock(&trace_types_lock);
+
+ spd.nr_pages = i;
+
+ return splice_to_pipe(pipe, &spd);
+
+out_err:
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+}
+
static ssize_t
tracing_entries_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
.open = tracing_open_pipe,
.poll = tracing_poll_pipe,
.read = tracing_read_pipe,
+ .splice_read = tracing_splice_read_pipe,
.release = tracing_release_pipe,
};
trace_buf[len] = 0;
size = sizeof(*entry) + len + 1;
- event = ring_buffer_lock_reserve(tr->buffer, size, &irq_flags);
+ event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
if (!event)
goto out_unlock;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, irq_flags, pc);
- entry->ent.type = TRACE_PRINT;
entry->ip = ip;
entry->depth = depth;
memcpy(&entry->buf, trace_buf, len);
entry->buf[len] = 0;
- ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+ ring_buffer_unlock_commit(tr->buffer, event);
out_unlock:
spin_unlock_irqrestore(&trace_buf_lock, irq_flags);