[lttng-dev] [lttng-ust][PATCH V2] Add config time check for new gettid API

[Khem Raj]

On Fri, Jul 26, 2019 at 2:09 PM Sebastien Boisvert <sboisvert at gydle.com> wrote:
>
>
>
> On 2019-07-26 4:55 p.m., Khem Raj wrote:
> > On Fri, Jul 26, 2019 at 12:23 PM Sebastien Boisvert <sboisvert at gydle.com> wrote:
> >>
> >>
> >>
> >> On 2019-07-26 3:02 p.m., Khem Raj wrote:
> >>> glibc 2.30 introduced this function see [1]
> >>> so it's best to detect it
> >>> and provide fallback only if its not present
> >>
> >> nit:
> >>
> >> -if its not present
> >> +if it's not present
> >>
> >
> > I sent a v3 with this fixed.
> >
> >> I cloned the git repository of the glibc, but I could not find
> >> the definition of gettid().
> >>
> >> Do you know where it is located in glibc ?
> >>
> > see
> > https://sourceware.org/git/?p=glibc.git;a=commit;h=1d0fc213824eaa2a8f8c4385daaa698ee8fb7c92
> >
>
> In the commit diff at https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=1d0fc213824eaa2a8f8c4385daaa698ee8fb7c92;hp=f289e656ec8221756519a601042bc9fbe1b310fb
> I don't see the definition of gettid().
>
> I see the declaration.
>
> There are a bunch of *ABI changes (*.abilist), and test changes (*tst-*).
>

its a syscall wrapper which is generated during build from
sysdeps/unix/sysv/linux/syscalls.list

>
> >> Thanks.
> >>
> >>>
> >>> [1] https://sourceware.org/bugzilla/show_bug.cgi?id=6399
> >>>
> >>> Upstream-Status: Submitted [https://lists.lttng.org/pipermail/lttng-dev/2019-July/029131.html]
> >>>
> >>> Signed-off-by: Khem Raj <raj.khem at gmail.com>
> >>> ---
> >>> v2: Fix typos in commit message
> >>>
> >>>  configure.ac            | 1 +
> >>>  include/lttng/ust-tid.h | 7 +++++--
> >>>  2 files changed, 6 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/configure.ac b/configure.ac
> >>> index 7fa059a..b1099c1 100644
> >>> --- a/configure.ac
> >>> +++ b/configure.ac
> >>> @@ -137,6 +137,7 @@ AC_CHECK_FUNCS([ \
> >>>       clock_gettime \
> >>>       ftruncate \
> >>>       getpagesize \
> >>> +     gettid \
> >>>       gettimeofday \
> >>>       localeconv \
> >>>       memchr \
> >>> diff --git a/include/lttng/ust-tid.h b/include/lttng/ust-tid.h
> >>> index e669d7e..7995c78 100644
> >>> --- a/include/lttng/ust-tid.h
> >>> +++ b/include/lttng/ust-tid.h
> >>> @@ -26,7 +26,10 @@
> >>>   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> >>>   * SOFTWARE.
> >>>   */
> >>> -
> >>> +#include <config.h>
> >>> +#if HAVE_GETTID
> >>> +#include <unistd.h>
> >>> +#else
> >>>  #ifdef __linux__
> >>>  #include <syscall.h>
> >>>  #endif
> >>> @@ -49,5 +52,5 @@ static inline pid_t gettid(void)
> >>>       return getpid();
> >>>  }
> >>>  #endif
> >>> -
> >>> +#endif /* HAVE_GETTID */
> >>>  #endif /* _LTTNG_UST_TID_H */
> >>>