On Thu, 20 Feb 2014 17:44:31 +0900
Yoshihiro YUNOMAE <yoshihiro.yunomae...@hitachi.com> wrote:
> Current tracing_saved_cmdlines_read() implementation is naive;
> simply allocate a big buffer, construct output data on the
> buffer for each read operation, and then copy a portion of
> the buffer to the user space buffer. This can cause a couple of
> issues such as a slow memory allocation, high cpu usage, and a
> corruption of the output data.
>
> To address these issues, make saved_cmdlines use seq_read.
I changed the subject and change log to the following. The patch is
untouched:
tracing: Have saved_cmdlines use the seq_read infrastructure
Current tracing_saved_cmdlines_read() implementation is naive; It
allocates a large buffer, constructs output data to that buffer for
each read operation, and then copies a portion of the buffer to the
user space buffer. This has several issues such as slow memory
allocation, high CPU usage, and even corruption of the output data.
The seq_read infrastructure is made to handle this type of work.
By converting it to use seq_read() the code becomes smaller,
simplified, as well as correct.
-- Steve
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