X-Git-Url: https://git.stricted.de/?a=blobdiff_plain;f=kernel%2Ftrace%2Ftrace.c;h=7d083107a044fe76b69375f9569176185a421b63;hb=bdecc6d1840bca102c4eb6113c6218e1ae8913f5;hp=7920b754458a57e9d7855d1c258a970da2eaa48f;hpb=eff333fa3be237a02175c5f6719ea2c0753b398d;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7920b754458a..7d083107a044 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3187,11 +3187,17 @@ static int tracing_open(struct inode *inode, struct file *file)
 	/* If this file was open for write, then erase contents */
 	if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
 		int cpu = tracing_get_cpu(inode);
+		struct trace_buffer *trace_buf = &tr->trace_buffer;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+		if (tr->current_trace->print_max)
+			trace_buf = &tr->max_buffer;
+#endif
 
 		if (cpu == RING_BUFFER_ALL_CPUS)
-			tracing_reset_online_cpus(&tr->trace_buffer);
+			tracing_reset_online_cpus(trace_buf);
 		else
-			tracing_reset(&tr->trace_buffer, cpu);
+			tracing_reset(trace_buf, cpu);
 	}
 
 	if (file->f_mode & FMODE_READ) {
@@ -4313,13 +4319,6 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
 	struct trace_array *tr = iter->tr;
 	ssize_t sret;
 
-	/* return any leftover data */
-	sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
-	if (sret != -EBUSY)
-		return sret;
-
-	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))
@@ -4332,6 +4331,14 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
 	 * is protected.
 	 */
 	mutex_lock(&iter->mutex);
+
+	/* return any leftover data */
+	sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
+	if (sret != -EBUSY)
+		goto out;
+
+	trace_seq_init(&iter->seq);
+
 	if (iter->trace->read) {
 		sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
 		if (sret)
@@ -4543,7 +4550,10 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 
 	spd.nr_pages = i;
 
-	ret = splice_to_pipe(pipe, &spd);
+	if (i)
+		ret = splice_to_pipe(pipe, &spd);
+	else
+		ret = 0;
 out:
 	splice_shrink_spd(&spd);
 	return ret;
@@ -4848,7 +4858,7 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
 	tracing_reset_online_cpus(&tr->trace_buffer);
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-	if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer)
+	if (tr->max_buffer.buffer)
 		ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func);
 	tracing_reset_online_cpus(&tr->max_buffer);
 #endif
@@ -5363,11 +5373,6 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 	}
 #endif
 
-	if (splice_grow_spd(pipe, &spd)) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
 	if (*ppos & (PAGE_SIZE - 1)) {
 		ret = -EINVAL;
 		goto out;
@@ -5381,6 +5386,11 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 		len &= PAGE_MASK;
 	}
 
+	if (splice_grow_spd(pipe, &spd)) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
  again:
 	trace_access_lock(iter->cpu_file);
 	entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);
@@ -5436,21 +5446,22 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 	if (!spd.nr_pages) {
 		if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) {
 			ret = -EAGAIN;
-			goto out;
+			goto out_shrink;
 		}
 		mutex_unlock(&trace_types_lock);
 		ret = iter->trace->wait_pipe(iter);
 		mutex_lock(&trace_types_lock);
 		if (ret)
-			goto out;
+			goto out_shrink;
 		if (signal_pending(current)) {
 			ret = -EINTR;
-			goto out;
+			goto out_shrink;
 		}
 		goto again;
 	}
 
 	ret = splice_to_pipe(pipe, &spd);
+out_shrink:
 	splice_shrink_spd(&spd);
 out:
 	mutex_unlock(&trace_types_lock);
@@ -5661,11 +5672,13 @@ ftrace_trace_snapshot_callback(struct ftrace_hash *hash,
 		return ret;
 
  out_reg:
-	ret = register_ftrace_function_probe(glob, ops, count);
+	ret = alloc_snapshot(&global_trace);
+	if (ret < 0)
+		goto out;
 
-	if (ret >= 0)
-		alloc_snapshot(&global_trace);
+	ret = register_ftrace_function_probe(glob, ops, count);
 
+ out:
 	return ret < 0 ? ret : 0;
 }
 
@@ -6306,7 +6319,7 @@ static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t m
 	int ret;
 
 	/* Paranoid: Make sure the parent is the "instances" directory */
-	parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+	parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias);
 	if (WARN_ON_ONCE(parent != trace_instance_dir))
 		return -ENOENT;
 
@@ -6333,7 +6346,7 @@ static int instance_rmdir(struct inode *inode, struct dentry *dentry)
 	int ret;
 
 	/* Paranoid: Make sure the parent is the "instances" directory */
-	parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+	parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias);
 	if (WARN_ON_ONCE(parent != trace_instance_dir))
 		return -ENOENT;