Re: [dpdk-dev] [PATCH] eal/linux: add operation LOCK_NB to flock()

[Tonghao Zhang <xiangxia.m.yue@gmail.com>]

On Thu, Mar 25, 2021 at 4:25 PM <xiangxia.m.yue@gmail.com> wrote:
>
> From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
ping
> The hugepage of different size, 2MB, 1GB may be mounted on
> the same directory (e.g /dev/hugepages). Then dpdk
> primary process will be blocked. To address this issue,
> add the LOCK_NB flags to flock().
>
> $ cat /proc/mounts
> ...
> none /dev/hugepages hugetlbfs rw,seclabel,relatime,pagesize=1024M 0 0
> none /dev/hugepages hugetlbfs rw,seclabel,relatime,pagesize=2M 0 0
>
> Add more details for err logs.
>
> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> ---
>  lib/librte_eal/linux/eal_hugepage_info.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/lib/librte_eal/linux/eal_hugepage_info.c b/lib/librte_eal/linux/eal_hugepage_info.c
> index d97792cadeb6..1ff76e539053 100644
> --- a/lib/librte_eal/linux/eal_hugepage_info.c
> +++ b/lib/librte_eal/linux/eal_hugepage_info.c
> @@ -451,9 +451,12 @@ hugepage_info_init(void)
>                 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
>
>                 /* if blocking lock failed */
> -               if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
> +               if (flock(hpi->lock_descriptor, LOCK_EX | LOCK_NB) == -1) {
>                         RTE_LOG(CRIT, EAL,
> -                               "Failed to lock hugepage directory!\n");
> +                               "Failed to lock hugepage directory! "
> +                               "The hugepage dir (%s) was locked by "
> +                               "other processes or self twice.\n",
> +                               hpi->hugedir);
>                         break;
>                 }
>                 /* clear out the hugepages dir from unused pages */
> --
> 2.27.0
>


-- 
Best regards, Tonghao