From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michalik, Michal Date: Tue, 19 Apr 2022 13:27:07 +0000 Subject: [Intel-wired-lan] [PATCH net v1] ice: fix PTP stale Tx timestamps cleanup In-Reply-To: <280c31b8-9f70-a0b5-2450-510903bd0d4e@molgen.mpg.de> References: <20220414102358.13486-1-michal.michalik@intel.com> <280c31b8-9f70-a0b5-2450-510903bd0d4e@molgen.mpg.de> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: Hi Paul, Much thanks for your kind review of my first community patch. Please excuse me for a delay in answering - Monday 18th was a Public Holiday here in Poland. > -----Original Message----- > From: Paul Menzel > Sent: Friday, April 15, 2022 6:37 PM > To: Michalik, Michal > Cc: intel-wired-lan at lists.osuosl.org > Subject: Re: [Intel-wired-lan] [PATCH net v1] ice: fix PTP stale Tx timestamps cleanup > > Dear Michal, > > > Thank you for your patch. > > Am 14.04.22 um 12:23 schrieb Michal Michalik: >> Read stale PTP Tx timestamps from PHY on cleanup. >> >> After running out of Tx timestamps request handlers hardware (HW) stops >> reporting finished requests. Function ice_ptp_tx_tstamp_cleanup() used >> to only cleanup stale handlers in driver and was leaving the hardware > > Nit: clean up Good catch - I should have used verb instead of noun. Will fix it in v2. > >> registers not read. Not reading stale PTP Tx timestamps prevents next >> interrupts from arriving and makes timestamping not usable. > > Nit: unusable Thanks - lesson learned. Will fix it in v2. > > Do you have a method, how to force the network device to run out of > timestamps request handlers? Unlucky - I don't have anything convenient. Both reproducing this bug and proving fix for it is working correctly was done by performing stability tests for multiple hours (using linuxptp project). > >> Fixes: ea9b847cda64 ("ice: enable transmit timestamps for E810 devices") >> Signed-off-by: Michal Michalik >> Reviewed-by: Jacob Keller >> --- >> drivers/net/ethernet/intel/ice/ice_ptp.c | 9 +++++++-- >> 1 file changed, 7 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c >> index a1cd332..826a508 100644 >> --- a/drivers/net/ethernet/intel/ice/ice_ptp.c >> +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c >> @@ -2287,6 +2287,7 @@ ice_ptp_init_tx_e810(struct ice_pf *pf, struct ice_ptp_tx *tx) >> >> /** >> * ice_ptp_tx_tstamp_cleanup - Cleanup old timestamp requests that got dropped >> + * @hw: pointer to the hw struct >> * @tx: PTP Tx tracker to clean up >> * >> * Loop through the Tx timestamp requests and see if any of them have been >> @@ -2295,7 +2296,7 @@ ice_ptp_init_tx_e810(struct ice_pf *pf, struct ice_ptp_tx *tx) >> * timestamp will never be captured. This might happen if the packet gets >> * discarded before it reaches the PHY timestamping block. >> */ >> -static void ice_ptp_tx_tstamp_cleanup(struct ice_ptp_tx *tx) >> +static void ice_ptp_tx_tstamp_cleanup(struct ice_hw *hw, struct ice_ptp_tx *tx) >> { >> u8 idx; >> >> @@ -2304,11 +2305,15 @@ static void ice_ptp_tx_tstamp_cleanup(struct ice_ptp_tx *tx) >> >> for_each_set_bit(idx, tx->in_use, tx->len) { >> struct sk_buff *skb; >> + u64 raw_tstamp; >> >> /* Check if this SKB has been waiting for too long */ >> if (time_is_after_jiffies(tx->tstamps[idx].start + 2 * HZ)) >> continue; >> >> + ice_read_phy_tstamp(hw, tx->quad, idx + tx->quad_offset, >> + &raw_tstamp); >> + > > Are compilers or code analyzer going to complain, that nothing will be > done with `raw_tstamp`? Is there some attribute, that it?s unused? Maybe > also add a comment, this is just to read the value, and it?s not going > to be used. > I haven't noticed any complaints from compiler. This function is used in different places, where all parameters are used. Do you think we should consider changing ice_read_phy_tstamp() so it would be able to accept tstamp equal to NULL and remove this unused raw_tstamp from here? If we leave it as is I will add a comment, according to your suggestion. >> spin_lock(&tx->lock); >> skb = tx->tstamps[idx].skb; >> tx->tstamps[idx].skb = NULL; >> @@ -2330,7 +2335,7 @@ static void ice_ptp_periodic_work(struct kthread_work *work) >> >> ice_ptp_update_cached_phctime(pf); >> >> - ice_ptp_tx_tstamp_cleanup(&pf->ptp.port.tx); >> + ice_ptp_tx_tstamp_cleanup(&pf->hw, &pf->ptp.port.tx); >> >> /* Run twice a second */ >> kthread_queue_delayed_work(ptp->kworker, &ptp->work, > > Reviewed-by: Paul Menzel > > > Kind regards, > > Paul > Best regards, Micha? Michalik