Re: [dpdk-dev] [PATCH 1/2] ethdev: make flow API primary/secondary process safe

[Suanming Mou <suanmingm@nvidia.com>]

Hi Stephen,

> -----Original Message-----
> From: Stephen Hemminger <stephen@networkplumber.org>
> Sent: Tuesday, March 16, 2021 3:27 AM
> To: dev@dpdk.org
> Cc: Stephen Hemminger <stephen@networkplumber.org>; Suanming Mou
> <suanmingm@nvidia.com>
> Subject: [PATCH 1/2] ethdev: make flow API primary/secondary process safe
> 
> Posix mutex are not by default safe for protecting for usage from multiple
> processes. The flow ops mutex could be used by both primary and secondary
> processes.

Process safe is something more widely scope. I assume it should be another feature but not a bugfix for thread-safe?
And the fag RTE_ETH_DEV_FLOW_OPS_THREAD_SAFE we have added is just thread safe.

> 
> Bugzilla ID: 662
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> Fixes: 80d1a9aff7f6 ("ethdev: make flow API thread safe")
> Cc: suanmingm@nvidia.com
> ---
>  lib/librte_ethdev/rte_ethdev.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c index
> 6f514c388b4e..d1024df408a5 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c
> @@ -470,6 +470,7 @@ rte_eth_dev_allocate(const char *name)  {
>  	uint16_t port_id;
>  	struct rte_eth_dev *eth_dev = NULL;
> +	pthread_mutexattr_t attr;
>  	size_t name_len;
> 
>  	name_len = strnlen(name, RTE_ETH_NAME_MAX_LEN); @@ -506,7
> +507,10 @@ rte_eth_dev_allocate(const char *name)
>  	strlcpy(eth_dev->data->name, name, sizeof(eth_dev->data->name));
>  	eth_dev->data->port_id = port_id;
>  	eth_dev->data->mtu = RTE_ETHER_MTU;
> -	pthread_mutex_init(&eth_dev->data->flow_ops_mutex, NULL);
> +
> +	pthread_mutexattr_init(&attr);
> +	pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED);
> 
> +	pthread_mutex_init(&eth_dev->data->flow_ops_mutex, &attr);
> 
>  unlock:
>  	rte_spinlock_unlock(&eth_dev_shared_data->ownership_lock);
> --
> 2.30.2