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  1. 10 8月, 2018 3 次提交
  3. 22 7月, 2018 8 次提交
  5. 13 7月, 2018 3 次提交
  7. 30 6月, 2018 3 次提交
    • J
      s390/qeth: consistently re-enable device features · d025da9e
      由 Julian Wiedmann 提交于 
      commit e830baa9 ("qeth: restore device features after recovery") and
commit ce344356 ("s390/qeth: rely on kernel for feature recovery")
made sure that the HW functions for device features get re-programmed
after recovery.

But we missed that the same handling is also required when a card is
first set offline (destroying all HW context), and then online again.
Fix this by moving the re-enable action out of the recovery-only path.
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d025da9e
    • V
      s390/qeth: avoid using is_multicast_ether_addr_64bits on (u8 *)[6] · 9d0a58fb
      由 Vasily Gorbik 提交于 
      *ether_addr*_64bits functions have been introduced to optimize
performance critical paths, which access 6-byte ethernet address as u64
value to get "nice" assembly. A harmless hack works nicely on ethernet
addresses shoved into a structure or a larger buffer, until busted by
Kasan on smth like plain (u8 *)[6].

qeth_l2_set_mac_address calls qeth_l2_remove_mac passing
u8 old_addr[ETH_ALEN] as an argument.

Adding/removing macs for an ethernet adapter is not that performance
critical. Moreover is_multicast_ether_addr_64bits itself on s390 is not
faster than is_multicast_ether_addr:

is_multicast_ether_addr(%r2) -> %r2
llc	%r2,0(%r2)
risbg	%r2,%r2,63,191,0

is_multicast_ether_addr_64bits(%r2) -> %r2
llgc	%r2,0(%r2)
risbg	%r2,%r2,63,191,0

So, let's just use is_multicast_ether_addr instead of
is_multicast_ether_addr_64bits.

Fixes: bcacfcbc ("s390/qeth: fix MAC address update sequence")
Reviewed-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      9d0a58fb
    • J
      s390/qeth: fix race when setting MAC address · 4789a218
      由 Julian Wiedmann 提交于 
      When qeth_l2_set_mac_address() finds the card in a non-reachable state,
it merely copies the new MAC address into dev->dev_addr so that
__qeth_l2_set_online() can later register it with the HW.

But __qeth_l2_set_online() may very well be running concurrently, so we
can't trust the card state without appropriate locking:
If the online sequence is past the point where it registers
dev->dev_addr (but not yet in SOFTSETUP state), any address change needs
to be properly programmed into the HW. Otherwise the netdevice ends up
with a different MAC address than what's set in the HW, and inbound
traffic is not forwarded as expected.

This is most likely to occur for OSD in LPAR, where
commit 21b1702a ("s390/qeth: improve fallback to random MAC address")
now triggers eg. systemd to immediately change the MAC when the netdevice
is registered with a NET_ADDR_RANDOM address.

Fixes: bcacfcbc ("s390/qeth: fix MAC address update sequence")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4789a218
  9. 28 4月, 2018 7 次提交
  11. 23 4月, 2018 2 次提交
    • J
      s390/qeth: fix request-side race during cmd IO timeout · db71bbbd
      由 Julian Wiedmann 提交于 
      Submitting a cmd IO request (usually on the WRITE device, but for IDX
also on the READ device) is currently done with ccw_device_start()
and a manual timeout in the caller.
On timeout, the caller cleans up the related resources (eg. IO buffer).
But 1) the IO might still be active and utilize those resources, and
    2) when the IO completes, qeth_irq() will attempt to clean up the
       same resources again.

Instead of introducing additional resource locking, switch to
ccw_device_start_timeout() to ensure IO termination after timeout, and
let the IRQ handler alone deal with cleaning up after a request.

This also removes a stray write->irq_pending reset from
clear_ipacmd_list(). The routine doesn't terminate any pending IO on
the WRITE device, so this should be handled properly via IO timeout
in the IRQ handler.
Signed-off-by: NJulian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      db71bbbd
    • J
      s390/qeth: fix MAC address update sequence · bcacfcbc
      由 Julian Wiedmann 提交于 
      When changing the MAC address on a L2 qeth device, current code first
unregisters the old address, then registers the new one.
If HW rejects the new address (or the IO fails), the device ends up with
no operable address at all.

Re-order the code flow so that the old address only gets dropped if the
new address was registered successfully. While at it, add logic to catch
some corner-cases.
Signed-off-by: NJulian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bcacfcbc
  13. 16 4月, 2018 1 次提交
  15. 22 3月, 2018 1 次提交
  17. 10 3月, 2018 6 次提交
  19. 21 12月, 2017 4 次提交
  21. 03 12月, 2017 2 次提交
    • J
      s390/qeth: build max size GSO skbs on L2 devices · 0cbff6d4
      由 Julian Wiedmann 提交于 
      The current GSO skb size limit was copy&pasted over from the L3 path,
where it is needed due to a TSO limitation.
As L2 devices don't offer TSO support (and thus all GSO skbs are
segmented before they reach the driver), there's no reason to restrict
the stack in how large it may build the GSO skbs.

Fixes: d52aec97 ("qeth: enable scatter/gather in layer 2 mode")
Signed-off-by: NJulian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0cbff6d4
    • J
      s390/qeth: fix GSO throughput regression · 6d69b1f1
      由 Julian Wiedmann 提交于 
      Using GSO with small MTUs currently results in a substantial throughput
regression - which is caused by how qeth needs to map non-linear skbs
into its IO buffer elements:
compared to a linear skb, each GSO-segmented skb effectively consumes
twice as many buffer elements (ie two instead of one) due to the
additional header-only part. This causes the Output Queue to be
congested with low-utilized IO buffers.

Fix this as follows:
If the MSS is low enough so that a non-SG GSO segmentation produces
order-0 skbs (currently ~3500 byte), opt out from NETIF_F_SG. This is
where we anticipate the biggest savings, since an SG-enabled
GSO segmentation produces skbs that always consume at least two
buffer elements.

Larger MSS values continue to get a SG-enabled GSO segmentation, since
1) the relative overhead of the additional header-only buffer element
becomes less noticeable, and
2) the linearization overhead increases.

With the throughput regression fixed, re-enable NETIF_F_SG by default to
reap the significant CPU savings of GSO.

Fixes: 5722963a ("qeth: do not turn on SG per default")
Reported-by: NNils Hoppmann <niho@de.ibm.com>
Signed-off-by: NJulian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6d69b1f1