On Thu, May 7, 2020 at 3:29 AM Dharmik Thakkar <dharmik.thak...@arm.com> wrote: > > Add a separate section for low-resolution generic counter > for ARM64 profiling methods. > > Signed-off-by: Dharmik Thakkar <dharmik.thak...@arm.com> > Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com> > Reviewed-by: Phil Yang <phil.y...@arm.com>
Acked-by: Jerin Jacob <jer...@marvell.com> > --- > doc/guides/prog_guide/profile_app.rst | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/doc/guides/prog_guide/profile_app.rst > b/doc/guides/prog_guide/profile_app.rst > index a36ebef4db99..e5d0e9079e11 100644 > --- a/doc/guides/prog_guide/profile_app.rst > +++ b/doc/guides/prog_guide/profile_app.rst > @@ -57,11 +57,16 @@ For more derails refer to the > `ARM64 specific PMU events enumeration > <http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.100095_0002_04_en/way1382543438508.html>`_. > > > -High-resolution cycle counter > -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > +Low-resolution generic counter > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > The default ``cntvct_el0`` based ``rte_rdtsc()`` provides a portable means to > -get a wall clock counter in user space. Typically it runs at <= 100MHz. > +get a wall clock counter in user space. Typically it runs at a lower clock > frequency than the CPU clock frequency. > +Cycles counted using this method should be scaled to CPU clock frequency. > + > + > +High-resolution cycle counter > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > The alternative method to enable ``rte_rdtsc()`` for a high resolution wall > clock counter is through the ARMv8 PMU subsystem. The PMU cycle counter runs > -- > 2.20.1 >
