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    SubjectRE: [PATCH RFC] bonding: rate-limit bonding driver inspect messages
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    > -----Original Message-----
    > From: Hangbin Liu <liuhangbin@gmail.com>
    > Sent: 18 February 2024 08:39 AM
    > To: Praveen Kannoju <praveen.kannoju@oracle.com>
    > Cc: j.vosburgh@gmail.com; andy@greyhouse.net; davem@davemloft.net; edumazet@google.com; kuba@kernel.org;
    > pabeni@redhat.com; netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Rajesh Sivaramasubramaniom
    > <rajesh.sivaramasubramaniom@oracle.com>; Rama Nichanamatlu <rama.nichanamatlu@oracle.com>; Manjunath Patil
    > <manjunath.b.patil@oracle.com>
    > Subject: Re: [PATCH RFC] bonding: rate-limit bonding driver inspect messages
    >
    > On Sat, Feb 17, 2024 at 12:39:44PM +0000, Praveen Kannoju wrote:
    > > > -----Original Message-----
    > > > From: Hangbin Liu <liuhangbin@gmail.com>
    > > > Sent: 16 February 2024 02:33 PM
    > > > To: Praveen Kannoju <praveen.kannoju@oracle.com>
    > > > Cc: j.vosburgh@gmail.com; andy@greyhouse.net; davem@davemloft.net;
    > > > edumazet@google.com; kuba@kernel.org; pabeni@redhat.com;
    > > > netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Rajesh
    > > > Sivaramasubramaniom <rajesh.sivaramasubramaniom@oracle.com>; Rama
    > > > Nichanamatlu <rama.nichanamatlu@oracle.com>; Manjunath Patil
    > > > <manjunath.b.patil@oracle.com>
    > > > Subject: Re: [PATCH RFC] bonding: rate-limit bonding driver inspect
    > > > messages
    > > >
    > > > 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
    > >
    > > Thank you, Hangbin.
    > >
    > > The routine bond_mii_monitor() periodically inspects the slave carrier state in order to detect for state changes, on a state change
    > internally records it and does the state change action.
    > >
    > > Parked-to-Parked state changes goes through transient state. As an example for Up to Down, BOND_LINK_UP to
    > BOND_LINK_DOWN, is thru BOND_LINK_FAIL. In order to attain next parked state or transient state bond needs rtnl mutex. If in a
    > situation it cannot get it, a state change wouldn't happen. In order to achieve a state change as quickly as possible
    > bond_mii_monitor() reschedules itself to come around after 1 msec.
    >
    > I think a large miimon downdelay/updelay setting could reduce this.
    >
    > > And every single come around reinspects the link and sees a state change compared to its internally recorded, which in reality
    > internal state could be not changed earlier as failed to get rtnl lock, and throws again log indicating it sees a state change. If attaining
    > rtnl mutex take long say hypothetical 5 secs, then bond logs 5000 state change message. 1 message at every 1 msec.
    >
    > Anyway, setting the rate limit do reduce the message flood. Would you please summarise the paragraph and add it in commit
    > description when post the formal patch?
    >
    > thanks
    > Hangbin

    Thank you very much, Hangbin.

    I've added the summary on why we intend to rate-limit the messages in the commit, and re-sent the formal patch.

    -
    Praveen.

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