tracing: use pointer error returns for __tracing_open

Impact: fix compile warning and clean up

When I first wrote __tracing_open, instead of passing the error
code via the ERR_PTR macros, I lazily used a separate parameter
to hold the return for errors.

When Frederic Weisbecker updated that function, he used the Linux
kernel ERR_PTR for the returns. This caused the parameter return
to possibly not be initialized on error. gcc correctly pointed this
out with a warning.

This patch converts the entire function to use the Linux kernel
ERR_PTR macro methods.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This commit is contained in:
Steven Rostedt 2009-02-27 00:12:38 -05:00
parent d8e83d26b5
commit 85a2f9b46f

View file

@ -1684,23 +1684,20 @@ static struct seq_operations tracer_seq_ops = {
};
static struct trace_iterator *
__tracing_open(struct inode *inode, struct file *file, int *ret)
__tracing_open(struct inode *inode, struct file *file)
{
long cpu_file = (long) inode->i_private;
void *fail_ret = ERR_PTR(-ENOMEM);
struct trace_iterator *iter;
struct seq_file *m;
int cpu;
int cpu, ret;
if (tracing_disabled) {
*ret = -ENODEV;
return NULL;
}
if (tracing_disabled)
return ERR_PTR(-ENODEV);
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (!iter) {
*ret = -ENOMEM;
goto out;
}
if (!iter)
return ERR_PTR(-ENOMEM);
/*
* We make a copy of the current tracer to avoid concurrent
@ -1708,10 +1705,9 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
*/
mutex_lock(&trace_types_lock);
iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL);
if (!iter->trace) {
*ret = -ENOMEM;
if (!iter->trace)
goto fail;
}
if (current_trace)
*iter->trace = *current_trace;
@ -1750,9 +1746,11 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
}
/* TODO stop tracer */
*ret = seq_open(file, &tracer_seq_ops);
if (*ret)
ret = seq_open(file, &tracer_seq_ops);
if (ret < 0) {
fail_ret = ERR_PTR(ret);
goto fail_buffer;
}
m = file->private_data;
m->private = iter;
@ -1762,7 +1760,6 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
mutex_unlock(&trace_types_lock);
out:
return iter;
fail_buffer:
@ -1775,7 +1772,7 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
kfree(iter->trace);
kfree(iter);
return ERR_PTR(-ENOMEM);
return fail_ret;
}
int tracing_open_generic(struct inode *inode, struct file *filp)
@ -1815,9 +1812,12 @@ static int tracing_release(struct inode *inode, struct file *file)
static int tracing_open(struct inode *inode, struct file *file)
{
int ret;
struct trace_iterator *iter;
int ret = 0;
__tracing_open(inode, file, &ret);
iter = __tracing_open(inode, file);
if (IS_ERR(iter))
ret = PTR_ERR(iter);
return ret;
}
@ -1825,11 +1825,13 @@ static int tracing_open(struct inode *inode, struct file *file)
static int tracing_lt_open(struct inode *inode, struct file *file)
{
struct trace_iterator *iter;
int ret;
int ret = 0;
iter = __tracing_open(inode, file, &ret);
iter = __tracing_open(inode, file);
if (!ret)
if (IS_ERR(iter))
ret = PTR_ERR(iter);
else
iter->iter_flags |= TRACE_FILE_LAT_FMT;
return ret;