Re: [PATCH net-next 2/2] devlink: Add auto dump flag to health reporter

Jiri Pirko
2020-03-26T10:22:49Z

Thu, Mar 26, 2020 at 01:01:35AM CET, kuba@kernel.org wrote:
>On Wed, 25 Mar 2020 21:38:35 +0200 Eran Ben Elisha wrote:
>> On 3/25/2020 9:08 PM, Jiri Pirko wrote:
>> > Wed, Mar 25, 2020 at 07:45:29PM CET, kuba@kernel.org wrote:
>> >> On Wed, 25 Mar 2020 15:26:24 +0200 Eran Ben Elisha wrote:
>> >>> On low memory system, run time dumps can consume too much memory. Add
>> >>> administrator ability to disable auto dumps per reporter as part of the
>> >>> error flow handle routine.
>> >>>
>> >>> This attribute is not relevant while executing
>> >>> DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET.
>> >>>
>> >>> By default, auto dump is activated for any reporter that has a dump method,
>> >>> as part of the reporter registration to devlink.
>> >>>
>> >>> Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
>> >>> Reviewed-by: Jiri Pirko <jiri@mellanox.com>
>> >>> ---
>> >>> include/uapi/linux/devlink.h | 2 ++
>> >>> net/core/devlink.c | 26 ++++++++++++++++++++++----
>> >>> 2 files changed, 24 insertions(+), 4 deletions(-)
>> >>>
>> >>> diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
>> >>> index dfdffc42e87d..e7891d1d2ebd 100644
>> >>> --- a/include/uapi/linux/devlink.h
>> >>> +++ b/include/uapi/linux/devlink.h
>> >>> @@ -429,6 +429,8 @@ enum devlink_attr {
>> >>> DEVLINK_ATTR_NETNS_FD, /* u32 */
>> >>> DEVLINK_ATTR_NETNS_PID, /* u32 */
>> >>> DEVLINK_ATTR_NETNS_ID, /* u32 */
>> >>> +
>> >>> + DEVLINK_ATTR_HEALTH_REPORTER_AUTO_DUMP, /* u8 */
>> >>> /* add new attributes above here, update the policy in devlink.c */
>> >>>
>> >>> __DEVLINK_ATTR_MAX,
>> >>> diff --git a/net/core/devlink.c b/net/core/devlink.c
>> >>> index ad69379747ef..e14bf3052289 100644
>> >>> --- a/net/core/devlink.c
>> >>> +++ b/net/core/devlink.c
>> >>> @@ -4837,6 +4837,7 @@ struct devlink_health_reporter {
>> >>> struct mutex dump_lock; /* lock parallel read/write from dump buffers */
>> >>> u64 graceful_period;
>> >>> bool auto_recover;
>> >>> + bool auto_dump;
>> >>> u8 health_state;
>> >>> u64 dump_ts;
>> >>> u64 dump_real_ts;
>> >>> @@ -4903,6 +4904,7 @@ devlink_health_reporter_create(struct devlink *devlink,
>> >>> reporter->devlink = devlink;
>> >>> reporter->graceful_period = graceful_period;
>> >>> reporter->auto_recover = !!ops->recover;
>> >>> + reporter->auto_dump = !!ops->dump;
>> >>> mutex_init(&reporter->dump_lock);
>> >>> refcount_set(&reporter->refcount, 1);
>> >>> list_add_tail(&reporter->list, &devlink->reporter_list);
>> >>> @@ -4983,6 +4985,10 @@ devlink_nl_health_reporter_fill(struct sk_buff *msg,
>> >>> nla_put_u64_64bit(msg, DEVLINK_ATTR_HEALTH_REPORTER_DUMP_TS_NS,
>> >>> reporter->dump_real_ts, DEVLINK_ATTR_PAD))
>> >>> goto reporter_nest_cancel;
>> >>> + if (reporter->ops->dump &&
>> >>> + nla_put_u8(msg, DEVLINK_ATTR_HEALTH_REPORTER_AUTO_DUMP,
>> >>> + reporter->auto_dump))
>> >>> + goto reporter_nest_cancel;
>> >>
>> >> Since you're making it a u8 - does it make sense to indicate to user
>> >
>> > Please don't be mistaken. u8 carries a bool here.
>
>Are you okay with limiting the value in the policy?

Well, not-0 means true. Do you think it is wise to limit to 0/1? …