[LTP] [PATCH 2/2] c: Use $LTP_TIMEOUT_MUL also in retry functions

[Li Wang]

On Thu, Jul 18, 2019 at 4:40 PM Petr Vorel <pvorel@suse.cz> wrote:
>...
>  #ifndef TST_COMMON_H__
> @@ -51,15 +40,22 @@
>
>  #define TST_RETRY_FN_EXP_BACKOFF(FUNC, ERET, MAX_DELAY)        \
>  ({     int tst_delay_ = 1;                                             \
> +       float m = 1;    \
> +       char *mul = getenv("LTP_TIMEOUT_MUL");  \

We also need a prefix/suffix in the variable definition to make sure
that it will
not alias with anything that has been passed to the FUNC, just like what we do
for the tst_delay_.

e.g. if the FUNC is defined as foo_func(m); the m variable will be aliased and
the function will do something very unexpected.

> +       if (mul) {      \
> +               m = atof(mul); \
> +               if (m < 1) \
> +                       tst_brk(TBROK, "Invalid timeout multiplier '%s'", mul); \

If we reverse some code order in tst_set_timeout() function, then here
we have no need to check if m < 1 again, since the LTP_TIMEOUT_MUL
valid check will be finished in setup() early phase.
(This comment is just FYI, and I also think it's OK to check twice.)

--------------------------------------
void tst_set_timeout(int timeout)
{
        float m = 1;
        char *mul = getenv("LTP_TIMEOUT_MUL");

        if (mul) {
                m = atof(mul);
                if (m < 1)
                        tst_brk(TBROK, "Invalid timeout multiplier '%s'", mul);
        }

        if (timeout == -1) {
                tst_res(TINFO, "Timeout per run is disabled");
                return;
        }

        results->timeout = timeout * m + 0.5;

        tst_res(TINFO, "Timeout per run is %uh %02um %02us",
                results->timeout/3600, (results->timeout%3600)/60,
                results->timeout % 60);

        if (getpid() == lib_pid)
                alarm(results->timeout);
        else
                heartbeat();
}


--
Regards,
Li Wang