On 24/09/19 12:34 AM, Jiri Olsa wrote:
> On Mon, Sep 16, 2019 at 11:56:45AM +0300, Adrian Hunter wrote:
>> Support directory output that contains a regular perf.data file. This is
>> preparation for adding support for putting a copy of /proc/kcore in that
>> directory.
>>
>> Distinguish the multiple file case from the regular (single) perf.data file
>> case by adding data->is_multi_file.
>
> SNIP
>
>> static int open_file_read(struct perf_data *data)
>> {
>> struct stat st;
>> @@ -302,12 +312,17 @@ static int open_dir(struct perf_data *data)
>> {
>> int ret;
>>
>> - /*
>> - * So far we open only the header, so we can read the data version and
>> - * layout.
>> - */
>> - if (asprintf(&data->file.path, "%s/header", data->path) < 0)
>> - return -1;
>> + if (perf_data__is_multi_file(data)) {
>> + /*
>> + * So far we open only the header, so we can read the data
>> version and
>> + * layout.
>> + */
>> + if (asprintf(&data->file.path, "%s/header", data->path) < 0)
>> + return -1;
>> + } else {
>> + if (asprintf(&data->file.path, "%s/perf.data", data->path) < 0)
>> + return -1;
>> + }
>
Thanks for replying :-)
> first, please note that there's support for perf.data directory code,
> but it's not been enabled yet, so we can do any changes there without
> breaking existing users
>
> currently the logic is prepared to have perf.data DIR_FORMAT feature
> to define the layout of the directory
>
> it'd be great to have just single point where we get directory layout,
> not checking on files names first and checking on DIR_FORMAT later
Ok, but what are you suggesting? Naming the data file "header" seems a bit
counter-intuitive in this case.
>
> also the kcore will be beneficial for other layouts,
> so would be great to make it somehow optional/switchable
In these patches it is, because it is not related to the DIR_FORMAT.
> one of the options could be to have DIR_FORMAT feature as the source
> of directory layout and it'd have bitmask of files/dirs (like kcore_dir)
> available in the directory
Is there an advantage to making optional files/dirs part of the format?
i.e. if they are there, use them otherwise don't.
