Re: [PATCH RFC] bonding: rate-limit bonding driver inspect messages

Hangbin Liu
2024-02-16T09:03:30Z

On Thu, Feb 15, 2024 at 10:55:54PM +0530, Praveen Kumar Kannoju wrote:
> Rate limit bond driver log messages, to prevent a log flood in a run-away
> situation, e.g couldn't get rtnl lock. Message flood leads to instability
> of system and loss of other crucial messages.

Hi Praveen,

The patch looks good to me. But would you please help explain why these
slave_info() are chosen under net_ratelimit?

Thanks
Hangbin
>
> v2: Use exising net_ratelimit() instead of introducing new rate-limit
> parameter.
>
> Signed-off-by: Praveen Kumar Kannoju <praveen.kannoju@oracle.com>
> ---
> drivers/net/bonding/bond_main.c | 36 ++++++++++++++++++++----------------
> 1 file changed, 20 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
> index 4e0600c..e92eba1 100644
> --- a/drivers/net/bonding/bond_main.c
> +++ b/drivers/net/bonding/bond_main.c
> @@ -2610,12 +2610,13 @@ static int bond_miimon_inspect(struct bonding *bond)
> commit++;
> slave->delay = bond->params.downdelay;
> if (slave->delay) {
> - slave_info(bond->dev, slave->dev, "link status down for %sinterface, disabling it in %d ms\n",
> - (BOND_MODE(bond) ==
> - BOND_MODE_ACTIVEBACKUP) ?
> - (bond_is_active_slave(slave) ?
> - "active " : "backup ") : "",
> - bond->params.downdelay * bond->params.miimon);
> + if (net_ratelimit())
> + slave_info(bond->dev, slave->dev, "link status down for %sinterface, disabling it in %d ms\n",
> + (BOND_MODE(bond) ==
> + BOND_MODE_ACTIVEBACKUP) ?
> + (bond_is_active_slave(slave) ?
> + "active " : "backup ") : "",
> + bond->params.downdelay * bond->params.miimon);
> }
> fallthrough;
> case BOND_LINK_FAIL:
> @@ -2623,9 +2624,10 @@ static int bond_miimon_inspect(struct bonding *bond)
> /* recovered before downdelay expired */
> bond_propose_link_state(slave, BOND_LINK_UP);
> slave->last_link_up = jiffies;
> - slave_info(bond->dev, slave->dev, "link status up again after %d ms\n",
> - (bond->params.downdelay - slave->delay) *
> - bond->params.miimon);
> + if (net_ratelimit())
> + slave_info(bond->dev, slave->dev, "link status up again after %d ms\n",
> + (bond->params.downdelay - slave->delay) *
> + bond->params.miimon);
> commit++;
> continue;
> }
> @@ -2648,18 +2650,20 @@ static int bond_miimon_inspect(struct bonding *bond)
> slave->delay = bond->params.updelay;
>
> if (slave->delay) {
> - slave_info(bond->dev, slave->dev, "link status up, enabling it in %d ms\n",
> - ignore_updelay ? 0 :
> - bond->params.updelay *
> - bond->params.miimon);
> + if (net_ratelimit())
> + slave_info(bond->dev, slave->dev, "link status up, enabling it in %d ms\n",
> + ignore_updelay ? 0 :
> + bond->params.updelay *
> + bond->params.miimon);
> }
> fallthrough;
> case BOND_LINK_BACK:
> if (!link_state) {
> bond_propose_link_state(slave, BOND_LINK_DOWN);
> - slave_info(bond->dev, slave->dev, "link status down again after %d ms\n",
> - (bond->params.updelay - slave->delay) *
> - bond->params.miimon);
> + if (net_ratelimit())
> + slave_info(bond->dev, slave->dev, "link status down again after %d ms\n",
> + (bond->params.updelay - slave->delay) *
> + bond->params.miimon);
> commit++;
> continue;
> }
> --
> 1.8.3.1
>