Re: [patch net-next v2 00/20] net: sched: convert cls ndo_setup_tc offload calls to per-block callbacks

From: Jakub Kicinski <kubakici@wp.pl>
To: Jiri Pirko <jiri@resnulli.us>
Cc: "Nambiar, Amritha" <amritha.nambiar@intel.com>,
	Alexander Duyck <alexander.duyck@gmail.com>,
	David Miller <davem@davemloft.net>,
	Netdev <netdev@vger.kernel.org>,
	Jamal Hadi Salim <jhs@mojatatu.com>,
	Cong Wang <xiyou.wangcong@gmail.com>,
	mlxsw@mellanox.com, Andrew Lunn <andrew@lunn.ch>,
	Vivien Didelot <vivien.didelot@savoirfairelinux.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Michael Chan <michael.chan@broadcom.com>,
	Ganesh Goudar <ganeshgr@chelsio.com>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
	Saeed Mahameed <saeedm@mellanox.com>,
	Matan Barak <matanb@mellanox.com>,
	Leon Romanovsky <leonro@mellanox.com>,
	idosch@mellanox.com, Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Simon Horman <simon.horman@netronome.com>,
Subject: Re: [patch net-next v2 00/20] net: sched: convert cls ndo_setup_tc offload calls to per-block callbacks
Date: Fri, 27 Oct 2017 17:52:00 -0700	[thread overview]
Message-ID: <20171027175200.018ebe65@cakuba.netronome.com> (raw)
In-Reply-To: <20171027072730.GB1980@nanopsycho.orion>

On Fri, 27 Oct 2017 09:27:30 +0200, Jiri Pirko wrote:
> >>> 2.       Deleting the ingress qdisc fails to remove filters added in
> >>> HW. Filters in SW gets deleted.
> >>>
> >>> We haven’t exactly root-caused this, the changes being extensive, but
> >>> our guess is again something wrong with the offload check or similar
> >>> while unregistering the block callback (tcf_block_cb_unregister) and
> >>> further to the classifier (CLS_U32/CLS_FLOWER etc.) with the
> >>> DESTROY/REMOVE command.  
> >> 
> >> Hmm. How does this worked previously. I mean, do you see change of
> >> behaviour? I'm asking because I don't see how rules added only to HW
> >> could be removed, driver should care of it. Or are you talking about
> >> rules added to both SW and HW?  
> >
> >These are rules added to both SW and HW. Previously all cls_* had
> >ndo_setup_tc calls based on the offload capability.
> >
> >commit 8d26d5636d "net: sched: avoid ndo_setup_tc calls for
> >TC_SETUP_CLS*" removed this bit to work with the new block callback. Is
> >there something similar in the block callback flow while acting on the
> >tcf_proto destroy call initiated when the qdisc is cleared?  
> 
> Yes, it is the same.

FWIW I also see what Amritha and Alex are describing here, for cls_bpf
there are no DESTROYs coming on rmmod or qdisc del.  There is a DESTROY
if I manually remove the filter (or if an ADD with skip_sw fails).