Re: Re: [PATCH 3/5] trace-cmd: Support trace-agent of virtio-trace

[Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>]

Hi Steven,

(2012/08/22 22:51), Steven Rostedt wrote:
> On Wed, 2012-08-22 at 17:43 +0900, Yoshihiro YUNOMAE wrote:
>> Add read path and control path to use trace-agent of virtio-trace.
>> When we use trace-agent, trace-cmd will be used as follows:
>> 	# AGENT_READ_DIR=/tmp/virtio-trace/tracing \
>> 	  AGENT_CTL=/tmp/virtio-trace/agent-ctl-path.in \
>> 	  TRACING_DIR=/tmp/virtio-trace/debugfs/tracing \\
>
> Ha! You used "TRACING_DIR" but patch one introduces TRACE_DIR. Lets
> change this to DEBUG_TRACING_DIR instead anyway.

Oh, sorry for the confusion.

> Also, I don't like the generic environment variables. Perhaps
> VIRTIO_TRACE_DIR, or AGENT_TRACE_DIR and AGENT_TRACE_CTL. Lets try to
> keep the environment namespace sparse.

OK, I'll change these name of environment variables as follows:
     AGENT_READ_DIR
     AGENT_TRACE_CTL
     GUEST_TRACING_DIR

>> 	  trace-cmd record -e "sched:*"
>> Here, AGENT_READ_DIR is the path for a reading directory of virtio-trace,
>> AGENT_CTL is a control path of trace-agent, and TRACING_DIR is a debugfs path
>> of a guest.
>>
>> Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
>> ---
>>
>>   trace-cmd.h      |    1 +
>>   trace-recorder.c |   57 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
>>   trace-util.c     |   18 +++++++++++++++++
>>   3 files changed, 75 insertions(+), 1 deletions(-)
>>
>> diff --git a/trace-cmd.h b/trace-cmd.h
>> index f904dc5..75506ed 100644
>> --- a/trace-cmd.h
>> +++ b/trace-cmd.h
>> @@ -72,6 +72,7 @@ static inline int tracecmd_host_bigendian(void)
>>   }
>>
>>   char *tracecmd_find_tracing_dir(void);
>> +char *guest_agent_tracing_read_dir(void);
>>
>>   /* --- Opening and Reading the trace.dat file --- */
>>
>> diff --git a/trace-recorder.c b/trace-recorder.c
>> index 215affc..3b750e9 100644
>> --- a/trace-recorder.c
>> +++ b/trace-recorder.c
>> @@ -33,6 +33,7 @@
>>   #include <unistd.h>
>>   #include <ctype.h>
>>   #include <errno.h>
>> +#include <stdbool.h>
>>
>>   #include "trace-cmd.h"
>>
>> @@ -43,6 +44,8 @@ struct tracecmd_recorder {
>>   	int		page_size;
>>   	int		cpu;
>>   	int		stop;
>> +	int		ctl_fd;
>> +	bool		agent_existing;
>
> Thanks for the reminder. I need to convert a lot to use 'bool' instead.

I'll change 'int' just for flag to use 'bool' as much as possible
after finishing this patch set.

>>   };
>>
>>   void tracecmd_free_recorder(struct tracecmd_recorder *recorder)
>> @@ -59,11 +62,29 @@ void tracecmd_free_recorder(struct tracecmd_recorder *recorder)
>>   	free(recorder);
>>   }
>>
>> +static char *use_trace_agent_dir(char *ctl_path,
>> +					struct tracecmd_recorder *recorder)
>> +{
>> +	ctl_path = strdup(ctl_path);
>> +	if (!ctl_path)
>> +		die("malloc");
>> +	warning("Use environmental control path: %s\n", ctl_path);
>
> s/Use/Using/

OK, I'll correct this.

Thank you,

-- 
Yoshihiro YUNOMAE
Software Platform Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: yoshihiro.yunomae.ez@hitachi.com