Re: [dpdk-dev] [PATCH] timer: allow first subsystem init from secondary

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 08-May-19 11:17 PM, Erik Gabriel Carrillo wrote:
> Since memzones can be reserved from secondary processes as well as
> primary processes, if the first call to the timer subsystem init
> function occurs in a secondary process, we should allow it to succeed.
> 
> Fixes: c0749f7096c7 ("timer: allow management in shared memory")
> 
> Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
> ---
>   lib/librte_timer/rte_timer.c | 52 +++++++++++++++++++++++---------------------
>   1 file changed, 27 insertions(+), 25 deletions(-)
> 
> diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
> index 9f2e921..c0f5b87 100644
> --- a/lib/librte_timer/rte_timer.c
> +++ b/lib/librte_timer/rte_timer.c
> @@ -25,6 +25,7 @@
>   #include <rte_memzone.h>
>   #include <rte_malloc.h>
>   #include <rte_compat.h>
> +#include <rte_errno.h>
>   
>   #include "rte_timer.h"
>   
> @@ -155,40 +156,41 @@ rte_timer_subsystem_init_v1905(void)
>   	struct rte_timer_data *data;
>   	int i, lcore_id;
>   	static const char *mz_name = "rte_timer_mz";
> +	const size_t data_arr_size =
> +				RTE_MAX_DATA_ELS * sizeof(*rte_timer_data_arr);
> +	bool do_full_init;
>   
>   	if (rte_timer_subsystem_initialized)
>   		return -EALREADY;
>   
> -	if (rte_eal_process_type() != RTE_PROC_PRIMARY) {
> -		mz = rte_memzone_lookup(mz_name);
> -		if (mz == NULL)
> -			return -EEXIST;
> +lookup:
> +	mz = rte_memzone_lookup(mz_name);

Wouldn't it be better to attempt to reserve outright, and then do a 
lookup on EEXIST?

> +	if (mz == NULL) {
> +		mz = rte_memzone_reserve_aligned(mz_name, data_arr_size,
> +				SOCKET_ID_ANY, 0, RTE_CACHE_LINE_SIZE);
> +		if (mz == NULL) {
> +			if (rte_errno == EEXIST)
> +				goto lookup;
>   


-- 
Thanks,
Anatoly