Re: [PATCH 4/7] xfs: introduce table-based init for error behaviors

Brian Foster
2016-05-05T14:10:52Z

On Wed, May 04, 2016 at 05:43:17PM +0200, Carlos Maiolino wrote:
> Before we start expanding the number of error classes and errors we
> can configure behaviour for, we need a simple and clear way to
> define the default behaviour that we initialized each mount with.
> Introduce a table based method for keeping the initial configuration
> in, and apply that to the existing initialization code.
>
> Changelog:
>
> V3:
> - Replace all .fail_speed fields by .max_retries, once the code will no
> longer use .fail_speed to decide when it should fail
> - The "Default" attribute is also in lower-case (default). I don't
> believe it's a good idea to have a mixed-case attribute names in sysfs.
>
> Signed-off-by: Dave Chinner <dchinner@redhat.com>
> Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

> fs/xfs/xfs_sysfs.c | 72 +++++++++++++++++++++++++++++++++++++++++++++---------
> 1 file changed, 60 insertions(+), 12 deletions(-)
>
> diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c
> index 0a9adcd..2a5b1cf 100644
> --- a/fs/xfs/xfs_sysfs.c
> +++ b/fs/xfs/xfs_sysfs.c
> @@ -395,11 +395,67 @@ struct kobj_type xfs_error_ktype = {
> .release = xfs_sysfs_release,
> };
>
> +/*
> + * Error initialization tables. These need to be ordered in the same
> + * order as the enums used to index the array. All class init tables need to
> + * define a "default" behaviour as the first entry, all other entries can be
> + * empty.
> + */
> +struct xfs_error_init {
> + char *name;
> + int max_retries;
> +};
> +
> +static const struct xfs_error_init xfs_error_meta_init[XFS_ERR_ERRNO_MAX] = {
> + { .name = "default",
> + .max_retries = -1,
> + },
> +};
> +
> +static int
> +xfs_error_sysfs_init_class(
> + struct xfs_mount *mp,
> + int class,
> + const char *parent_name,
> + struct xfs_kobj *parent_kobj,
> + const struct xfs_error_init init[])
> +{
> + struct xfs_error_cfg *cfg;
> + int error;
> + int i;
> +
> + ASSERT(class < XFS_ERR_CLASS_MAX);
> +
> + error = xfs_sysfs_init(parent_kobj, &xfs_error_ktype,
> + &mp->m_error_kobj, parent_name);
> + if (error)
> + return error;
> +
> + for (i = 0; i < XFS_ERR_ERRNO_MAX; i++) {
> + cfg = &mp->m_error_cfg[class][i];
> + error = xfs_sysfs_init(&cfg->kobj, &xfs_error_cfg_ktype,
> + parent_kobj, init[i].name);
> + if (error)
> + goto out_error;
> +
> + cfg->max_retries = init[i].max_retries;
> + }
> + return 0;
> +
> +out_error:
> + /* unwind the entries that succeeded */
> + for (i--; i >= 0; i--) {
> + cfg = &mp->m_error_cfg[class][i];
> + xfs_sysfs_del(&cfg->kobj);
> + }
> + xfs_sysfs_del(parent_kobj);
> + return error;
> +}
> +
> int
> xfs_error_sysfs_init(
> struct xfs_mount *mp)
> {
> - struct xfs_error_cfg *cfg;
> int error;
>
> /* .../xfs/<dev>/error/ */
> @@ -409,22 +465,14 @@ xfs_error_sysfs_init(
> return error;
>
> /* .../xfs/<dev>/error/metadata/ */
> - error = xfs_sysfs_init(&mp->m_error_meta_kobj, &xfs_error_ktype,
> - &mp->m_error_kobj, "metadata");
> + error = xfs_error_sysfs_init_class(mp, XFS_ERR_METADATA,
> + "metadata", &mp->m_error_meta_kobj,
> + xfs_error_meta_init);
> if (error)
> goto out_error;
>
> - cfg = &mp->m_error_cfg[XFS_ERR_METADATA][XFS_ERR_DEFAULT];
> - error = xfs_sysfs_init(&cfg->kobj, &xfs_error_cfg_ktype,
> - &mp->m_error_meta_kobj, "default");
> - if (error)
> - goto out_error_meta;
> - cfg->max_retries = -1;
> -
> return 0;
>
> -out_error_meta:
> - xfs_sysfs_del(&mp->m_error_meta_kobj);
> out_error:
> xfs_sysfs_del(&mp->m_error_kobj);
> return error;
> --
> 2.4.11
>
> _______________________________________________
> xfs mailing list
> xfs@oss.sgi.com
> http://oss.sgi.com/mailman/listinfo/xfs