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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c142
1 files changed, 97 insertions, 45 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7974ba20557d..20c755e018ca 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -235,13 +235,33 @@ void trace_array_put(struct trace_array *this_tr)
mutex_unlock(&trace_types_lock);
}
-int filter_current_check_discard(struct ring_buffer *buffer,
- struct ftrace_event_call *call, void *rec,
- struct ring_buffer_event *event)
+int filter_check_discard(struct ftrace_event_file *file, void *rec,
+ struct ring_buffer *buffer,
+ struct ring_buffer_event *event)
{
- return filter_check_discard(call, rec, buffer, event);
+ if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) &&
+ !filter_match_preds(file->filter, rec)) {
+ ring_buffer_discard_commit(buffer, event);
+ return 1;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(filter_check_discard);
+
+int call_filter_check_discard(struct ftrace_event_call *call, void *rec,
+ struct ring_buffer *buffer,
+ struct ring_buffer_event *event)
+{
+ if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
+ !filter_match_preds(call->filter, rec)) {
+ ring_buffer_discard_commit(buffer, event);
+ return 1;
+ }
+
+ return 0;
}
-EXPORT_SYMBOL_GPL(filter_current_check_discard);
+EXPORT_SYMBOL_GPL(call_filter_check_discard);
cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu)
{
@@ -575,6 +595,28 @@ void free_snapshot(struct trace_array *tr)
}
/**
+ * tracing_alloc_snapshot - allocate snapshot buffer.
+ *
+ * This only allocates the snapshot buffer if it isn't already
+ * allocated - it doesn't also take a snapshot.
+ *
+ * This is meant to be used in cases where the snapshot buffer needs
+ * to be set up for events that can't sleep but need to be able to
+ * trigger a snapshot.
+ */
+int tracing_alloc_snapshot(void)
+{
+ struct trace_array *tr = &global_trace;
+ int ret;
+
+ ret = alloc_snapshot(tr);
+ WARN_ON(ret < 0);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tracing_alloc_snapshot);
+
+/**
* trace_snapshot_alloc - allocate and take a snapshot of the current buffer.
*
* This is similar to trace_snapshot(), but it will allocate the
@@ -587,11 +629,10 @@ void free_snapshot(struct trace_array *tr)
*/
void tracing_snapshot_alloc(void)
{
- struct trace_array *tr = &global_trace;
int ret;
- ret = alloc_snapshot(tr);
- if (WARN_ON(ret < 0))
+ ret = tracing_alloc_snapshot();
+ if (ret < 0)
return;
tracing_snapshot();
@@ -603,6 +644,12 @@ void tracing_snapshot(void)
WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used");
}
EXPORT_SYMBOL_GPL(tracing_snapshot);
+int tracing_alloc_snapshot(void)
+{
+ WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used");
+ return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(tracing_alloc_snapshot);
void tracing_snapshot_alloc(void)
{
/* Give warning */
@@ -843,9 +890,12 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
if (isspace(ch)) {
parser->buffer[parser->idx] = 0;
parser->cont = false;
- } else {
+ } else if (parser->idx < parser->size - 1) {
parser->cont = true;
parser->buffer[parser->idx++] = ch;
+ } else {
+ ret = -EINVAL;
+ goto out;
}
*ppos += read;
@@ -1261,21 +1311,6 @@ int is_tracing_stopped(void)
}
/**
- * ftrace_off_permanent - disable all ftrace code permanently
- *
- * This should only be called when a serious anomally has
- * been detected. This will turn off the function tracing,
- * ring buffers, and other tracing utilites. It takes no
- * locks and can be called from any context.
- */
-void ftrace_off_permanent(void)
-{
- tracing_disabled = 1;
- ftrace_stop();
- tracing_off_permanent();
-}
-
-/**
* tracing_start - quick start of the tracer
*
* If tracing is enabled but was stopped by tracing_stop,
@@ -1509,7 +1544,8 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
#endif
((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
- (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
+ (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
+ (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
}
EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
@@ -1630,7 +1666,7 @@ trace_function(struct trace_array *tr,
entry->ip = ip;
entry->parent_ip = parent_ip;
- if (!filter_check_discard(call, entry, buffer, event))
+ if (!call_filter_check_discard(call, entry, buffer, event))
__buffer_unlock_commit(buffer, event);
}
@@ -1714,7 +1750,7 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer,
entry->size = trace.nr_entries;
- if (!filter_check_discard(call, entry, buffer, event))
+ if (!call_filter_check_discard(call, entry, buffer, event))
__buffer_unlock_commit(buffer, event);
out:
@@ -1816,7 +1852,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
trace.entries = entry->caller;
save_stack_trace_user(&trace);
- if (!filter_check_discard(call, entry, buffer, event))
+ if (!call_filter_check_discard(call, entry, buffer, event))
__buffer_unlock_commit(buffer, event);
out_drop_count:
@@ -2008,7 +2044,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
entry->fmt = fmt;
memcpy(entry->buf, tbuffer, sizeof(u32) * len);
- if (!filter_check_discard(call, entry, buffer, event)) {
+ if (!call_filter_check_discard(call, entry, buffer, event)) {
__buffer_unlock_commit(buffer, event);
ftrace_trace_stack(buffer, flags, 6, pc);
}
@@ -2063,7 +2099,7 @@ __trace_array_vprintk(struct ring_buffer *buffer,
memcpy(&entry->buf, tbuffer, len);
entry->buf[len] = '\0';
- if (!filter_check_discard(call, entry, buffer, event)) {
+ if (!call_filter_check_discard(call, entry, buffer, event)) {
__buffer_unlock_commit(buffer, event);
ftrace_trace_stack(buffer, flags, 6, pc);
}
@@ -2760,7 +2796,7 @@ static void show_snapshot_main_help(struct seq_file *m)
seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n");
seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n");
seq_printf(m, "# Takes a snapshot of the main buffer.\n");
- seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n");
+ seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n");
seq_printf(m, "# (Doesn't have to be '2' works with any number that\n");
seq_printf(m, "# is not a '0' or '1')\n");
}
@@ -2964,6 +3000,11 @@ int tracing_open_generic(struct inode *inode, struct file *filp)
return 0;
}
+bool tracing_is_disabled(void)
+{
+ return (tracing_disabled) ? true: false;
+}
+
/*
* Open and update trace_array ref count.
* Must have the current trace_array passed to it.
@@ -3142,19 +3183,23 @@ tracing_write_stub(struct file *filp, const char __user *ubuf,
return count;
}
-static loff_t tracing_seek(struct file *file, loff_t offset, int origin)
+loff_t tracing_lseek(struct file *file, loff_t offset, int whence)
{
+ int ret;
+
if (file->f_mode & FMODE_READ)
- return seq_lseek(file, offset, origin);
+ ret = seq_lseek(file, offset, whence);
else
- return 0;
+ file->f_pos = ret = 0;
+
+ return ret;
}
static const struct file_operations tracing_fops = {
.open = tracing_open,
.read = seq_read,
.write = tracing_write_stub,
- .llseek = tracing_seek,
+ .llseek = tracing_lseek,
.release = tracing_release,
};
@@ -4198,12 +4243,6 @@ out:
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)
{
@@ -4215,7 +4254,7 @@ static const struct pipe_buf_operations tracing_pipe_buf_ops = {
.map = generic_pipe_buf_map,
.unmap = generic_pipe_buf_unmap,
.confirm = generic_pipe_buf_confirm,
- .release = tracing_pipe_buf_release,
+ .release = generic_pipe_buf_release,
.steal = generic_pipe_buf_steal,
.get = generic_pipe_buf_get,
};
@@ -4899,7 +4938,7 @@ static const struct file_operations snapshot_fops = {
.open = tracing_snapshot_open,
.read = seq_read,
.write = tracing_snapshot_write,
- .llseek = tracing_seek,
+ .llseek = tracing_lseek,
.release = tracing_snapshot_release,
};
@@ -5454,12 +5493,12 @@ static struct ftrace_func_command ftrace_snapshot_cmd = {
.func = ftrace_trace_snapshot_callback,
};
-static int register_snapshot_cmd(void)
+static __init int register_snapshot_cmd(void)
{
return register_ftrace_command(&ftrace_snapshot_cmd);
}
#else
-static inline int register_snapshot_cmd(void) { return 0; }
+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)
@@ -5869,6 +5908,8 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size
rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
+ buf->tr = tr;
+
buf->buffer = ring_buffer_alloc(size, rb_flags);
if (!buf->buffer)
return -ENOMEM;
@@ -6253,6 +6294,17 @@ void trace_init_global_iter(struct trace_iterator *iter)
iter->trace = iter->tr->current_trace;
iter->cpu_file = RING_BUFFER_ALL_CPUS;
iter->trace_buffer = &global_trace.trace_buffer;
+
+ if (iter->trace && iter->trace->open)
+ iter->trace->open(iter);
+
+ /* Annotate start of buffers if we had overruns */
+ if (ring_buffer_overruns(iter->trace_buffer->buffer))
+ iter->iter_flags |= TRACE_FILE_ANNOTATE;
+
+ /* Output in nanoseconds only if we are using a clock in nanoseconds. */
+ if (trace_clocks[iter->tr->clock_id].in_ns)
+ iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
}
void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)