Re: [PATCH tip/core/rcu 5/8] rcutorture: Print symbolic name for rcu_torture_writer_state

Josh Triplett
2015-12-05T01:02:29Z

On Fri, Dec 04, 2015 at 04:23:49PM -0800, Paul E. McKenney wrote:
> Currently, rcu_torture_writer_state is printed as an integer, which slows
> debugging. This commit therefore prints a symbolic name in addition to
> the integer.
>
> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> ---
> kernel/rcu/rcutorture.c | 24 +++++++++++++++++++++++-
> 1 file changed, 23 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
> index d89328e260df..adbb194e2b5d 100644
> --- a/kernel/rcu/rcutorture.c
> +++ b/kernel/rcu/rcutorture.c
> @@ -162,6 +162,27 @@ static int rcu_torture_writer_state;
> #define RTWS_SYNC 7
> #define RTWS_STUTTER 8
> #define RTWS_STOPPING 9
> +static char * const rcu_torture_writer_state_names[] = {

Shouldn't this use "static const char * const"? Also, see below.

> + "RTWS_FIXED_DELAY",
> + "RTWS_DELAY",
> + "RTWS_REPLACE",
> + "RTWS_DEF_FREE",
> + "RTWS_EXP_SYNC",
> + "RTWS_COND_GET",
> + "RTWS_COND_SYNC",
> + "RTWS_SYNC",
> + "RTWS_STUTTER",
> + "RTWS_STOPPING",
> +};
> +
> +char *rcu_torture_writer_state_getname(void)

This should return "const char *", I think.

> +{
> + unsigned int i = READ_ONCE(rcu_torture_writer_state);
> +
> + if (i >= ARRAY_SIZE(rcu_torture_writer_state_names))
> + return "???";
> + return rcu_torture_writer_state_names[i];
> +}
>
> #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
> #define RCUTORTURE_RUNNABLE_INIT 1
> @@ -1307,7 +1328,8 @@ rcu_torture_stats_print(void)
>
> rcutorture_get_gp_data(cur_ops->ttype,
> &flags, &gpnum, &completed);
> - pr_alert("??? Writer stall state %d g%lu c%lu f%#x\n",
> + pr_alert("??? Writer stall state %s(%d) g%lu c%lu f%#x\n",
> + rcu_torture_writer_state_getname(),
> rcu_torture_writer_state,
> gpnum, completed, flags);
> show_rcu_gp_kthreads();
> --
> 2.5.2
>