Re: [PATCH v3] eal: allow to exclude memseg from core dump

[Jerin Jacob <jerinjacobk@gmail.com>]

On Tue, Dec 14, 2021 at 8:49 PM Gaoxiang Liu <gaoxiangliu0@163.com> wrote:
>
> Some DPDK application is allocated storage partition of 8G(or smaller)
> If coredump happens, the application doesn't work because of
> insufficient storage space.
> The patch provides a config that means whether the memseg memory
> is allowed to exclude from core dump.
> The DPDK application can choose to open it according to the actual
> situation.
>
> Fixes: d72e4042c5eb ("mem: exclude unused memory from core dump")

This is patch is a feature, not a fix. So you can remove this

> Cc: stable@dpdk.org

This is patch is a feature, not a fix. So you can remove this


>
> Signed-off-by: Gaoxiang Liu <liugaoxiang@huawei.com>
>
> ---
> v2:
> * Fixed compile issues.
>
> v3:
> * Fixed review issues. madvise is replaced by eal_mem_set_dump(),
> * and The type of huge_dont_dump_flag has been changed to bool.
> ---
>  doc/guides/linux_gsg/linux_eal_parameters.rst | 4 ++++
>  lib/eal/common/eal_internal_cfg.h             | 1 +
>  lib/eal/common/eal_options.h                  | 3 ++-
>  lib/eal/linux/eal.c                           | 4 ++++
>  lib/eal/linux/eal_memalloc.c                  | 3 +++
>  lib/eal/unix/eal_unix_memory.c                | 7 +++++--
>  6 files changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/doc/guides/linux_gsg/linux_eal_parameters.rst b/doc/guides/linux_gsg/linux_eal_parameters.rst

Since you are adding it in unix/eal_unix_memory.c it is applicable for
freebsd too.
Please update options and documentation for freebsd.

> index 74df2611b5..b6805bc6df 100644
> --- a/doc/guides/linux_gsg/linux_eal_parameters.rst
> +++ b/doc/guides/linux_gsg/linux_eal_parameters.rst
> @@ -93,6 +93,10 @@ Memory-related options
>
>      Free hugepages back to system exactly as they were originally allocated.
>
> +*   ``--memseg-dont-dump``
> +
> +    Allow to exclude memseg from core dump.
> +
>  Other options
>  ~~~~~~~~~~~~~
>
> diff --git a/lib/eal/common/eal_internal_cfg.h b/lib/eal/common/eal_internal_cfg.h
> index d6c0470eb8..a7c34b88db 100644
> --- a/lib/eal/common/eal_internal_cfg.h
> +++ b/lib/eal/common/eal_internal_cfg.h
> @@ -87,6 +87,7 @@ struct internal_config {
>                         /**< user defined mbuf pool ops name */
>         unsigned num_hugepage_sizes;      /**< how many sizes on this system */
>         struct hugepage_info hugepage_info[MAX_HUGEPAGE_SIZES];
> +       bool memseg_dont_dump_flag;
>         enum rte_iova_mode iova_mode ;    /**< Set IOVA mode on this system  */
>         rte_cpuset_t ctrl_cpuset;         /**< cpuset for ctrl threads */
>         volatile unsigned int init_complete;
> diff --git a/lib/eal/common/eal_options.h b/lib/eal/common/eal_options.h
> index 8e4f7202a2..013aad4cfc 100644
> --- a/lib/eal/common/eal_options.h
> +++ b/lib/eal/common/eal_options.h
> @@ -87,7 +87,8 @@ enum {
>         OPT_NO_TELEMETRY_NUM,
>  #define OPT_FORCE_MAX_SIMD_BITWIDTH  "force-max-simd-bitwidth"
>         OPT_FORCE_MAX_SIMD_BITWIDTH_NUM,
> -
> +#define OPT_MEMSEG_DONT_DUMP     "memseg-dont-dump"
> +       OPT_MEMSEG_DONT_DUMP_NUM,
>         OPT_LONG_MAX_NUM
>  };
>
> diff --git a/lib/eal/linux/eal.c b/lib/eal/linux/eal.c
> index 60b4924838..8a47bf758a 100644
> --- a/lib/eal/linux/eal.c
> +++ b/lib/eal/linux/eal.c
> @@ -817,6 +817,10 @@ eal_parse_args(int argc, char **argv)
>                         internal_conf->match_allocations = 1;
>                         break;
>
> +               case OPT_MEMSEG_DONT_DUMP_NUM:
> +                       internal_conf->memseg_dont_dump_flag = 1;
> +                       break;
> +
>                 default:
>                         if (opt < OPT_LONG_MIN_NUM && isprint(opt)) {
>                                 RTE_LOG(ERR, EAL, "Option %c is not supported "
> diff --git a/lib/eal/linux/eal_memalloc.c b/lib/eal/linux/eal_memalloc.c
> index 337f2bc739..8e41537355 100644
> --- a/lib/eal/linux/eal_memalloc.c
> +++ b/lib/eal/linux/eal_memalloc.c
> @@ -663,6 +663,9 @@ alloc_seg(struct rte_memseg *ms, void *addr, int socket_id,
>         ms->iova = iova;
>         ms->socket_id = socket_id;
>
> +       if (internal_conf->memseg_dont_dump_flag)
> +               eal_mem_set_dump(addr, alloc_sz, false);
> +
>         return 0;
>
>  mapped:
> diff --git a/lib/eal/unix/eal_unix_memory.c b/lib/eal/unix/eal_unix_memory.c
> index 68ae93bd6e..44227aee95 100644
> --- a/lib/eal/unix/eal_unix_memory.c
> +++ b/lib/eal/unix/eal_unix_memory.c
> @@ -83,10 +83,13 @@ eal_mem_set_dump(void *virt, size_t size, bool dump)
>         int flags = dump ? EAL_DODUMP : EAL_DONTDUMP;
>         int ret = madvise(virt, size, flags);
>         if (ret) {
> -               RTE_LOG(DEBUG, EAL, "madvise(%p, %#zx, %d) failed: %s\n",
> +               RTE_LOG(INFO, EAL, "madvise(%p, %#zx, %d) failed: %s\n",
>                                 virt, size, flags, strerror(rte_errno));

probably ERR instead of INFO.


>                 rte_errno = errno;
> -       }
> +       } else
> +               RTE_LOG(INFO, EAL, "madvise(%p, %#zx, %d) success: %s\n",
> +                               virt, size, flags, __func__);

This should be DEBUG. Not INFO.

With above changes
Reviewed-by: Jerin Jacob <jerinj@marvell.com>


> +
>         return ret;
>  }
>
> --
> 2.32.0
>
>