[PATCH v3 3/7] eal: add lcore variable performance test

[Jerin Jacob]

On Thu, Sep 12, 2024 at 2:34 PM Mattias Rönnblom
<mattias.ronnblom at ericsson.com> wrote:
>
> Add basic micro benchmark for lcore variables, in an attempt to assure
> that the overhead isn't significantly greater than alternative
> approaches, in scenarios where the benefits aren't expected to show up
> (i.e., when plenty of cache is available compared to the working set
> size of the per-lcore data).
>
> Signed-off-by: Mattias Rönnblom <mattias.ronnblom at ericsson.com>
> ---
>  app/test/meson.build           |   1 +
>  app/test/test_lcore_var_perf.c | 160 +++++++++++++++++++++++++++++++++
>  2 files changed, 161 insertions(+)
>  create mode 100644 app/test/test_lcore_var_perf.c


> +static double
> +benchmark_access_method(void (*init_fun)(void), void (*update_fun)(void))
> +{
> +       uint64_t i;
> +       uint64_t start;
> +       uint64_t end;
> +       double latency;
> +
> +       init_fun();
> +
> +       start = rte_get_timer_cycles();
> +
> +       for (i = 0; i < ITERATIONS; i++)
> +               update_fun();
> +
> +       end = rte_get_timer_cycles();

Use precise variant. rte_rdtsc_precise() or so to be accurate