[PATCH 1/2] SDT markers listing by perf
Hemant
hkshaw@linux.vnet.ibm.com
Fri Sep 6 08:41:00 GMT 2013
Hi Namhyung,
On 09/06/2013 12:07 PM, Namhyung Kim wrote:
> Hi Hemant,
>
> On Wed, 04 Sep 2013 23:07:57 +0530, Hemant wrote:
>> On 09/04/2013 12:12 PM, Namhyung Kim wrote:
>>> On Tue, 03 Sep 2013 13:06:55 +0530, Hemant Kumar wrote:
>>>> + /*
>>>> + * Look for Section type = SHT_NOTE, flags = no SHF_ALLOC
>>>> + * and name = .note.stapsdt
>>>> + */
>>>> + scn = elf_section_by_name(elf, &ehdr, &shdr, NOTE_SCN, NULL);
>>>> + if (scn == NULL) {
>>>> + pr_err("%s section not found!\n", NOTE_SCN);
>>>> + goto out_end;
>>>> + }
>>>> +
>>>> + if (!(shdr.sh_type == SHT_NOTE) || (shdr.sh_flags & SHF_ALLOC))
>>>> + goto out_end;
>>>> +
>>>> + data = elf_getdata(scn, NULL);
>>>> +
>>>> + /* Get the notes */
>>>> + for (offset = 0; (next = gelf_getnote(data, offset, &nhdr, &name_off,
>>>> + &desc_off)) > 0; offset = next) {
>>>> + tmp = populate_note(&elf, (const char *)((long)(data->d_buf) +
>>>> + (long)desc_off),
>>>> + nhdr.n_descsz, nhdr.n_type);
>>> Shouldn't we check the name of note being "stapsdt" as well as version
>>> (type) 3?
>> Since, we are already fetching the section NOTE_SCN (".note.stapsdt")
>> and then we check for the type being SHT_NOTE and SHF_ALLOC, is it
>> required to do the same for the individual notes?
> I don't know. Now it seems only includes SDT notes with name being
> "stapsdt" and type being 3. But things can be changed in future..
>
> Thanks,
> Namhyung
>
Yeah that may be a case. Ok, will put a check on the individual markers
for their type.
Thanks
Hemant
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