Re: [PATCH net-next RFC v5 03/15] devlink: Add reload action stats

[Moshe Shemesh <moshe@nvidia.com>]

On 9/23/2020 9:42 PM, Jakub Kicinski wrote:
> External email: Use caution opening links or attachments
>
>
> On Fri, 18 Sep 2020 19:06:39 +0300 Moshe Shemesh wrote:
>> Add reload action stats to hold the history per reload action type and
>> limit level.
>>
>> For example, the number of times fw_activate has been performed on this
>> device since the driver module was added or if the firmware activation
>> was performed with or without reset.
>>
>> The function devlink_remote_reload_actions_performed() is exported to
>> enable also drivers update on reload actions performed, for example in
>> case firmware activation with reset finished successfully but was
>> initiated by remote host.
>>
>> Add devlink notification on stats update.
>>
>> Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
> I'd split this and the next patch by stat type (remote vs local).
> Rather than split them by collect / report.


OK.

>> diff --git a/include/net/devlink.h b/include/net/devlink.h
>> index d8c62d605381..f09f55a47d09 100644
>> --- a/include/net/devlink.h
>> +++ b/include/net/devlink.h
>> @@ -20,6 +20,9 @@
>>   #include <uapi/linux/devlink.h>
>>   #include <linux/xarray.h>
>>
>> +#define DEVLINK_RELOAD_ACTION_STATS_ARRAY_SIZE \
>> +     (__DEVLINK_RELOAD_ACTION_LIMIT_LEVEL_MAX * __DEVLINK_RELOAD_ACTION_MAX)
>> +
>>   struct devlink_ops;
>>
>>   struct devlink {
>> @@ -38,6 +41,8 @@ struct devlink {
>>        struct list_head trap_policer_list;
>>        const struct devlink_ops *ops;
>>        struct xarray snapshot_ids;
>> +     u32 reload_action_stats[DEVLINK_RELOAD_ACTION_STATS_ARRAY_SIZE];
>> +     u32 remote_reload_action_stats[DEVLINK_RELOAD_ACTION_STATS_ARRAY_SIZE];
>>        struct device *dev;
>>        possible_net_t _net;
>>        struct mutex lock; /* Serializes access to devlink instance specific objects such as
>> @@ -1400,6 +1405,9 @@ void
>>   devlink_health_reporter_recovery_done(struct devlink_health_reporter *reporter);
>>
>>   bool devlink_is_reload_failed(const struct devlink *devlink);
>> +void devlink_remote_reload_actions_performed(struct devlink *devlink,
>> +                                          enum devlink_reload_action_limit_level limit_level,
>> +                                          unsigned long actions_performed);
>>
>>   void devlink_flash_update_begin_notify(struct devlink *devlink);
>>   void devlink_flash_update_end_notify(struct devlink *devlink);
>> diff --git a/net/core/devlink.c b/net/core/devlink.c
>> index fee6fcc7dead..1509c2ffb98b 100644
>> --- a/net/core/devlink.c
>> +++ b/net/core/devlink.c
>> @@ -3007,16 +3007,74 @@ bool devlink_is_reload_failed(const struct devlink *devlink)
>>   }
>>   EXPORT_SYMBOL_GPL(devlink_is_reload_failed);
>>
>> +static void
>> +__devlink_reload_action_stats_update(struct devlink *devlink,
>> +                                  u32 *reload_action_stats,
>> +                                  enum devlink_reload_action_limit_level limit_level,
>> +                                  unsigned long actions_performed)
>> +{
>> +     int stat_idx;
>> +     int action;
>> +
>> +     if (!actions_performed)
>> +             return;
>> +
>> +     if (WARN_ON(limit_level > DEVLINK_RELOAD_ACTION_LIMIT_LEVEL_MAX))
>> +             return;
>> +     for (action = 0; action <= DEVLINK_RELOAD_ACTION_MAX; action++) {
>> +             if (!test_bit(action, &actions_performed))
>> +                     continue;
>> +             stat_idx = limit_level * __DEVLINK_RELOAD_ACTION_MAX + action;
>> +             reload_action_stats[stat_idx]++;
>> +     }
>> +     devlink_notify(devlink, DEVLINK_CMD_NEW);
>> +}
>> +
>> +static void
>> +devlink_reload_action_stats_update(struct devlink *devlink,
>> +                                enum devlink_reload_action_limit_level limit_level,
>> +                                unsigned long actions_performed)
>> +{
>> +     __devlink_reload_action_stats_update(devlink, devlink->reload_action_stats,
>> +                                          limit_level, actions_performed);
>> +}
>> +
>> +/**
>> + *   devlink_remote_reload_actions_performed - Update devlink on reload actions
>> + *     performed which are not a direct result of devlink reload call.
>> + *
>> + *   This should be called by a driver after performing reload actions in case it was not
>> + *   a result of devlink reload call. For example fw_activate was performed as a result
>> + *   of devlink reload triggered fw_activate on another host.
>> + *   The motivation for this function is to keep data on reload actions performed on this
>> + *   function whether it was done due to direct devlink reload call or not.
>> + *
>> + *   @devlink: devlink
>> + *   @limit_level: reload action limit level
>> + *   @actions_performed: bitmask of actions performed
>> + */
>> +void devlink_remote_reload_actions_performed(struct devlink *devlink,
>> +                                          enum devlink_reload_action_limit_level limit_level,
>> +                                          unsigned long actions_performed)
>> +{
>> +     __devlink_reload_action_stats_update(devlink, devlink->remote_reload_action_stats,
>> +                                          limit_level, actions_performed);
>> +}
>> +EXPORT_SYMBOL_GPL(devlink_remote_reload_actions_performed);
>> +
>>   static int devlink_reload(struct devlink *devlink, struct net *dest_net,
>>                          enum devlink_reload_action action,
>>                          enum devlink_reload_action_limit_level limit_level,
>>                          struct netlink_ext_ack *extack, unsigned long *actions_performed)
>>   {
>> +     u32 remote_reload_action_stats[DEVLINK_RELOAD_ACTION_STATS_ARRAY_SIZE];
>>        int err;
>>
>>        if (!devlink->reload_enabled)
>>                return -EOPNOTSUPP;
>>
>> +     memcpy(remote_reload_action_stats, devlink->remote_reload_action_stats,
>> +            sizeof(remote_reload_action_stats));
>>        err = devlink->ops->reload_down(devlink, !!dest_net, action, limit_level, extack);
>>        if (err)
>>                return err;
>> @@ -3030,6 +3088,10 @@ static int devlink_reload(struct devlink *devlink, struct net *dest_net,
>>                return err;
>>
>>        WARN_ON(!test_bit(action, actions_performed));
>> +     /* protect from driver updating the remote action within devlink reload */
> s/protect from/catch/


Ack.

>> +     WARN_ON(memcmp(remote_reload_action_stats, devlink->remote_reload_action_stats,
>> +                    sizeof(remote_reload_action_stats)));
>> +     devlink_reload_action_stats_update(devlink, limit_level, *actions_performed);
>>        return 0;
>>   }
>>