mirror_ubuntu-kernels/drivers/net/ethernet/intel/i40e
Jacob Keller e4b433f4a7 i40e: reset all VFs in parallel when rebuilding PF
When there are a lot of active VFs, it can take multiple seconds to
finish resetting all of them during certain flows., which can cause some
VFs to fail to wait long enough for the reset to occur. The user might
see messages like "Never saw reset" or "Reset never finished" and the VF
driver will stop functioning properly.

The naive solution would be to simply increase the wait timer. We can
get much more clever. Notice that i40e_reset_vf is run in a serialized
fashion, and includes lots of delays.

There are two prominent delays which take most of the time. First, when
we begin resetting VFs, we have multiple 10ms delays which accrue
because we reset each VF in a serial fashion. These delays accumulate to
almost 4 seconds when handling the maximum number of VFs (128).

Secondly, there is a massive 50ms delay for each time we disable queues
on a VSI. This delay is necessary to allow HW to finish disabling queues
before we restore functionality. However, just like with the first case,
we are paying the cost for each VF, rather than disabling all VFs and
waiting once.

Both of these can be fixed, but required some previous refactoring to
handle the special case. First, we will need the
i40e_vsi_wait_queues_disabled function which was previously DCB
specific. Second, we will need to implement our own
i40e_vsi_stop_rings_no_wait function which will handle the stopping of
rings without the delays.

Finally, implement an i40e_reset_all_vfs function, which will first
start the reset of all VFs, and pay the wait cost all at once, rather
than serially waiting for each VF before we start processing then next
one. After the VF has been reset, we'll disable all the VF queues, and
then wait for them to disable. Again, we'll organize the flow such that
we pay the wait cost only once.

Finally, after we've disabled queues we'll go ahead and begin restoring
VF functionality. The result is reducing the wait time by a large factor
and ensuring that VFs do not timeout when waiting in the VF driver.

Change-ID: Ia6e8cf8d98131b78aec89db78afb8d905c9b12be
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-04-19 17:45:07 -07:00
..
i40e_adminq_cmd.h i40e: new AQ commands 2017-04-19 17:04:06 -07:00
i40e_adminq.c i40e: reduce wait time for adminq command completion 2017-04-19 17:38:25 -07:00
i40e_adminq.h i40e: reduce wait time for adminq command completion 2017-04-19 17:38:25 -07:00
i40e_alloc.h
i40e_client.c i40e: register existing client on probe 2017-04-06 20:22:28 -07:00
i40e_client.h i40e: KISS the client interface 2017-03-15 01:57:08 -07:00
i40e_common.c i40e: new AQ commands 2017-04-19 17:04:06 -07:00
i40e_dcb_nl.c i40e: Change some messages from info to debug only 2015-10-15 01:58:41 -07:00
i40e_dcb.c i40e: refactor DCB function 2016-02-16 19:04:08 -08:00
i40e_dcb.h i40e: Add parsing for CEE DCBX TLVs 2015-10-08 15:11:38 -07:00
i40e_debugfs.c i40e: dump VF information in debugfs 2017-04-19 16:38:23 -07:00
i40e_devids.h i40e: Add support for 25G devices 2016-12-06 20:59:43 -08:00
i40e_diag.c i40e: use BIT and BIT_ULL macros 2015-07-23 05:33:55 -07:00
i40e_diag.h
i40e_ethtool.c i40e: fix CONFIG_BUSY checks in i40e_set_settings function 2017-04-19 17:17:03 -07:00
i40e_fcoe.c i40e: store MAC/VLAN filters in a hash with the MAC Address as key 2016-10-31 14:26:40 -07:00
i40e_fcoe.h i40e: use BIT and BIT_ULL macros 2015-07-23 05:33:55 -07:00
i40e_hmc.c i40e: fix an uninitialized variable bug 2016-05-14 00:21:51 -07:00
i40e_hmc.h i40e: use BIT and BIT_ULL macros 2015-07-23 05:33:55 -07:00
i40e_lan_hmc.c i40e: use explicit cast from u16 to u8 2015-12-12 21:08:26 -08:00
i40e_lan_hmc.h
i40e_main.c i40e: reset all VFs in parallel when rebuilding PF 2017-04-19 17:45:07 -07:00
i40e_nvm.c i40e: Acquire NVM lock before reads on all devices 2017-03-14 17:52:32 -07:00
i40e_osdep.h i40e: Drop FCoE code from core driver files 2017-03-27 16:47:43 -07:00
i40e_prototype.h i40e: new AQ commands 2017-04-19 17:04:06 -07:00
i40e_ptp.c i40e: don't warn every time we clear an Rx timestamp register 2017-02-11 20:39:01 -08:00
i40e_register.h i40e: Expose some registers to program parser, FD and RSS logic 2016-02-18 23:49:31 -08:00
i40e_status.h
i40e_trace.h i40e/i40evf: Add tracepoints 2017-04-19 16:47:31 -07:00
i40e_txrx.c i40e/i40evf: Add tracepoints 2017-04-19 16:47:31 -07:00
i40e_txrx.h i40e/i40evf: Add support for padding start of frames 2017-04-08 02:53:51 -07:00
i40e_type.h i40e: new AQ commands 2017-04-19 17:04:06 -07:00
i40e_virtchnl_pf.c i40e: reset all VFs in parallel when rebuilding PF 2017-04-19 17:45:07 -07:00
i40e_virtchnl_pf.h i40e: reset all VFs in parallel when rebuilding PF 2017-04-19 17:45:07 -07:00
i40e_virtchnl.h i40e/i40evf: Add capability exchange for outer checksum 2017-04-06 20:14:51 -07:00
i40e.h i40e: reset all VFs in parallel when rebuilding PF 2017-04-19 17:45:07 -07:00
Makefile i40e/i40evf: Add tracepoints 2017-04-19 16:47:31 -07:00