Re: [PATCH 1/5] trace: Add a new readonly entry to report total buffer size

[Vaibhav Nagarnaik <vnagarnaik@google.com>]

On Fri, Jul 29, 2011 at 11:01 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> On Tue, 2011-07-26 at 15:59 -0700, Vaibhav Nagarnaik wrote:
>> The current file "buffer_size_kb" reports the size of per-cpu buffer and
>> not the overall memory allocated which could be misleading. A new file
>> "buffer_total_size_kb" adds up all the enabled CPU buffer sizes and
>> reports it. This is only a readonly entry.
>>
>> Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
>> ---
>>  kernel/trace/trace.c |   27 +++++++++++++++++++++++++++
>>  1 files changed, 27 insertions(+), 0 deletions(-)
>>
>> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
>> index e5df02c..ce57c55 100644
>> --- a/kernel/trace/trace.c
>> +++ b/kernel/trace/trace.c
>> @@ -3569,6 +3569,24 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
>>  }
>>
>>  static ssize_t
>> +tracing_total_entries_read(struct file *filp, char __user *ubuf,
>> +                             size_t cnt, loff_t *ppos)
>> +{
>> +     struct trace_array *tr = filp->private_data;
>> +     char buf[64];
>> +     int r, cpu;
>> +     unsigned long size = 0;
>> +
>> +     mutex_lock(&trace_types_lock);
>> +     for_each_tracing_cpu(cpu)
>> +             size += tr->entries >> 10;
>
> Could you make this consistent with buffer_size_kb as well. That is, if
> the buffer is "shrunk", could you have the expanded size printed as
> well.
>
> Thanks,
>
> -- Steve
>

Sure. I forgot about that.


Vaibhav Nagarnaik