Re: [PATCH V10 01/13] perf tools: add debug prints

[Adrian Hunter <adrian.hunter@intel.com>]

On 13/08/13 05:54, Namhyung Kim wrote:
> On Fri,  9 Aug 2013 13:51:47 +0300, Adrian Hunter wrote:
>> It is useful to see the arguments to perf_event_open
>> and whether the perf events ring buffer was mmapped
>> per-cpu or per-thread.  That information will now be
>> displayed when verbose is 2 i.e option -vv
> 
> I have two nitpicks below, but other than that it looks good, so
> 
> Acked-by: Namhyung Kim <namhyung@kernel.org>
> 
> 
> [SNIP]
> 
>> +#define __PRINT_ATTR(fmt, cast, field)  \
>> +	fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
>> +
>> +#define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
>> +#define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
>> +#define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
>> +#define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
>> +
>> +#define PRINT_ATTR2N(name1, field1, name2, field2)	\
>> +	fprintf(fp, "  %-19s %u    %-19s %u\n",		\
>> +	name1, attr->field1, name2, attr->field2)
>> +
>> +#define PRINT_ATTR2(field1, field2) \
>> +	PRINT_ATTR2N(#field1, field1, #field2, field2)
>> +
>> +static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
>> +{
>> +	size_t ret = 0;
>> +
>> +	ret += fprintf(fp, "------------------------------");
>> +	ret += fprintf(fp, "------------------------------\n");
> 
> We have 'graph_dotted_line' for this.
> 
> 
>> +	ret += fprintf(fp, "perf_event_attr:\n");
>> +
>> +	ret += PRINT_ATTR_U32(type);
>> +	ret += PRINT_ATTR_U32(size);
>> +	ret += PRINT_ATTR_X64(config);
>> +	ret += PRINT_ATTR_U64(sample_period);
>> +	ret += PRINT_ATTR_U64(sample_freq);
>> +	ret += PRINT_ATTR_X64(sample_type);
>> +	ret += PRINT_ATTR_X64(read_format);
>> +
>> +	ret += PRINT_ATTR2(disabled, inherit);
>> +	ret += PRINT_ATTR2(pinned, exclusive);
>> +	ret += PRINT_ATTR2(exclude_user, exclude_kernel);
>> +	ret += PRINT_ATTR2(exclude_hv, exclude_idle);
>> +	ret += PRINT_ATTR2(mmap, comm);
>> +	ret += PRINT_ATTR2(freq, inherit_stat);
>> +	ret += PRINT_ATTR2(enable_on_exec, task);
>> +	ret += PRINT_ATTR2(watermark, precise_ip);
>> +	ret += PRINT_ATTR2(mmap_data, sample_id_all);
>> +	ret += PRINT_ATTR2(exclude_host, exclude_guest);
>> +	ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
>> +			    "excl.callchain_user", exclude_callchain_user);
>> +
>> +	ret += PRINT_ATTR_U32(wakeup_events);
>> +	ret += PRINT_ATTR_U32(wakeup_watermark);
>> +	ret += PRINT_ATTR_X32(bp_type);
>> +	ret += PRINT_ATTR_X64(bp_addr);
>> +	ret += PRINT_ATTR_X64(config1);
>> +	ret += PRINT_ATTR_U64(bp_len);
>> +	ret += PRINT_ATTR_X64(config2);
>> +	ret += PRINT_ATTR_X64(branch_sample_type);
>> +	ret += PRINT_ATTR_X64(sample_regs_user);
>> +	ret += PRINT_ATTR_U32(sample_stack_user);
>> +
>> +	ret += fprintf(fp, "------------------------------");
>> +	ret += fprintf(fp, "------------------------------\n");
>> +
>> +	return ret;
>> +}
> 
> [SNIP]
> 
>> diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
>> index 925e0c3..381f4fd 100644
>> --- a/tools/perf/util/python.c
>> +++ b/tools/perf/util/python.c
>> @@ -8,6 +8,26 @@
>>  #include "cpumap.h"
>>  #include "thread_map.h"
>>  
>> +/*
>> + * Support debug printing even though util/debug.c is not linked.  That means
>> + * implementing 'verbose' and 'eprintf'.
>> + */
>> +int verbose;
>> +
>> +int eprintf(int level, const char *fmt, ...)
>> +{
>> +	va_list args;
>> +	int ret = 0;
>> +
>> +	if (verbose >= level) {
>> +		va_start(args, fmt);
>> +		ret = vfprintf(stderr, fmt, args);
>> +		va_end(args);
>> +	}
>> +
>> +	return ret;
>> +}
> 
> Not sure this duplication is the right way.  Maybe linking util/debug.c
> into the python extension and move trace_event() somewhere is a better
> approach.  But it'd make the util/debug.c more fragile?

trace_event is not the problem. ui_helpline__vshow is.  So eprintf has to be
re-implemented anyway.

> 
> Anyway this change could be splitted as a preparation patch.
> 
> Thanks,
> Namhyung
> 
>