Commit Graph

56 Commits

Author SHA1 Message Date
Jon Cooper
cce28794bc sfc: Make initial fill of RX descriptors synchronous
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-12-12 22:06:50 +00:00
Andrew Rybchenko
2ec030144f sfc: RX buffer allocation takes prefix size into account in IP header alignment
rx_prefix_size is 4-bytes aligned on Falcon/Siena (16 bytes), but it is equal
to 14 on EF10. So, it should be taken into account if arch requires IP header
to be 4-bytes aligned (via NET_IP_ALIGN).

Fixes: 8127d661e7 ('sfc: Add support for Solarflare SFC9100 family')
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-12-06 22:27:52 +00:00
Ben Hutchings
c47b2d9d56 sfc: Support ARFS for IPv6 flows
Extend efx_filter_rfs() to map TCP/IPv6 and UDP/IPv6 flows into
efx_filter_spec.  These are only supported on EF10; on Falcon and
Siena they will be rejected by efx_farch_filter_from_gen_spec().

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-09-20 19:32:00 +01:00
Ben Hutchings
f7a6d2c442 sfc: Update copyright banners
Update the dates for files that have been added to in 2012-2013.
Drop the 'Solarstorm' brand name that's still lingering here.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-29 23:34:51 +01:00
Jon Cooper
e8c68c0a09 sfc: Prepare for RX scatter on EF10
RX DMA scatter is always enabled on EF10.  Adjust the common RX
completion handling to allow for this.

RX completion events on EF10 include the length used from a single
descriptor, not the cumulative length used.  Add a field to struct
efx_rx_queue to hold the cumulative length.

[bwh: Also fix a related comment]
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-29 18:12:12 +01:00
Ben Hutchings
b883d0bd4a sfc: Document conditions for multicast replication vs filter replacement
Add the efx_filter_is_mc_recip() function to decide whether a filter
is for a multicast recipient and can coexist with other filters with
the same match values.  Update efx_filter_insert_filter() kernel-doc
to explain the conditions for this.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-29 18:12:07 +01:00
Ben Hutchings
3dced740c2 sfc: Add support for reading packet length from prefix
Define a flag for struct efx_rx_buffer and efx_rx_packet() that
indicates packet length must be read from the prefix.  If this
is set, read the length in __efx_rx_packet() (when the prefix
should have arrived in cache).

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-27 22:29:07 +01:00
Jon Cooper
43a3739d55 sfc: Generalise packet hash lookup to support EF10 RX prefix
EF10 uses an entirely different RX prefix format from Falcon-arch.
Extend struct efx_nic_type to describe this.

[bwh: Also replace the magic numbers used for the Falcon-arch RX prefix]
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-27 22:28:24 +01:00
Ben Hutchings
add7247718 sfc: Make most filter operations NIC-type-specific
Aside from accelerated RFS, there is almost nothing that can be shared
between the filter table implementations for the Falcon architecture
and EF10.

Move the few shared functions into efx.c and rx.c and the rest into
farch.c.  Introduce efx_nic_type operations for the implementation and
inline wrapper functions that call these.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-22 19:25:57 +01:00
Ben Hutchings
e42c3d85af sfc: Refactor queue teardown sequence to allow for EF10 flush behaviour
Currently efx_stop_datapath() will try to flush our DMA queues (if DMA
is enabled), then finalise software and hardware state for each queue.
However, for EF10 we must ask the MC to finalise each queue, which
implicitly starts flushing it, and then wait for the flush events.
We therefore need to delegate more of this to the NIC type.

Combine all the hardware operations into a new NIC-type operation
efx_nic_type::fini_dmaq, and call this before tearing down the
software state and buffers for all the DMA queues.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-21 19:49:23 +01:00
Ben Hutchings
d8aec745dd sfc: Stop RX refill before flushing RX queues
rx_queue::enabled guards refill, so rename it to reflect that.  Clear
it at the start of the queue teardown process rather than waiting for
the RX queue to be flushed.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-08-21 19:48:54 +01:00
Ben Hutchings
734d4e159b sfc: Fix memory leak when discarding scattered packets
Commit 2768935a46 ('sfc: reuse pages to avoid DMA mapping/unmapping
costs') did not fully take account of DMA scattering which was
introduced immediately before.  If a received packet is invalid and
must be discarded, we only drop a reference to the first buffer's
page, but we need to drop a reference for each buffer the packet
used.

I think this bug was missed partly because efx_recycle_rx_buffers()
was not renamed and so no longer does what its name says.  It does not
change the state of buffers, but only prepares the underlying pages
for recycling.  Rename it accordingly.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-05 01:29:15 -07:00
Ben Hutchings
636d73da27 sfc: Improve test for IOMMU in use
The device::iommu_group field may be set even if no IOMMU is in use.
iommu_present() is still a better indicator, although it doesn't tell
us whether *our* device is affected.

Reported-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-06-24 20:02:53 +01:00
Ben Hutchings
e79255de85 sfc: Do not pass non-TCP packets into GRO code
GRO can handle non-TCP packets and pass them up without coalescing,
but it has to do some extra work to parse the packet which we can
bypass using the hardware parse result.  (This condition yields a
false negative for TCP/IPv6 packets received by Falcon, but its
performance is already poor in that case due to lack of checksum
offload.)

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-06-24 20:00:32 +01:00
Jon Cooper
d4ef5b6f37 sfc: Increase size of RX SKB header area
This allows the SKB to hold the headers without reallocation more often.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-06-24 19:58:28 +01:00
Jon Cooper
c99dffc417 sfc: Enable RX checksum offload for packets not handled by GRO
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-06-24 19:58:27 +01:00
Ben Hutchings
950c54df1e sfc: Reduce RX scatter buffer size, and reduce alignment if appropriate
efx_start_datapath() asserts that we can fit 2 RX scatter buffers plus
a software structure, each appropriately aligned, into a single page.
Where L1_CACHE_BYTES == 256 and PAGE_SIZE == 4096, which is the case
on s390, this assertion fails.

The current scatter buffer size is also not a multiple of 64 or 128,
which are more common cache line sizes.  If we can make both the start
and end of a scatter buffer cache-aligned, this will reduce the need
for read-modify-write operations on inter- processor links.

Fix the alignment by reducing EFX_RX_USR_BUF_SIZE to 2048 - 256 ==
1792.  (We could use 2048 - L1_CACHE_BYTES, but EFX_RX_USR_BUF_SIZE
also affects user-level networking where a larger amount of
housekeeping data may be needed.  Although this version of the driver
does not support user-level networking, I prefer to keep scattering
behaviour consistent with the out-of-tree version.)

This still doesn't fix the s390 build because like most architectures
it has NET_IP_ALIGN == 2.  When NET_IP_ALIGN != 0 we cannot achieve
cache line alignment at either the start or end of a scatter buffer,
so there is actually no point in padding the buffers to a multiple of
the cache line size.  All we need is 4-byte alignment of the network
header, so do that.

Adjust the assertions accordingly.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-14 11:32:04 -07:00
Ben Hutchings
c14ff2ea2d sfc: Delete EFX_PAGE_IP_ALIGN, equivalent to NET_IP_ALIGN
The two architectures that define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
(powerpc and x86) now both define NET_IP_ALIGN as 0, so there is no
need for this optimisation any more.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-14 11:32:04 -07:00
stephen hemminger
debd0034de sfc: make local functions static
Trivial sparse detected functions that should be static.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-17 14:26:40 -04:00
Daniel Pieczko
1648a23fa1 sfc: allocate more RX buffers per page
Allocating 2 buffers per page is insanely inefficient when MTU is 1500
and PAGE_SIZE is 64K (as it usually is on POWER).  Allocate as many as
we can fit, and choose the refill batch size at run-time so that we
still always use a whole page at once.

[bwh: Fix loop condition to allow for compound pages; rebase]
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:15 +00:00
Ben Hutchings
179ea7f039 sfc: Replace efx_rx_is_last_buffer() with a flag
This condition is brittle and we have lots of flags to spare.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:14 +00:00
Daniel Pieczko
2768935a46 sfc: reuse pages to avoid DMA mapping/unmapping costs
On POWER systems, DMA mapping/unmapping operations are very expensive.
These changes reduce these costs by trying to reuse DMA mapped pages.

After all the buffers associated with a page have been processed and
passed up, the page is placed into a ring (if there is room).  For
each page that is required for a refill operation, a page in the ring
is examined to determine if its page count has fallen to 1, ie. the
kernel has released its reference to these packets.  If this is the
case, the page can be immediately added back into the RX descriptor
ring, without having to re-map it for DMA.

If the kernel is still holding a reference to this page, it is removed
from the ring and unmapped for DMA.  Then a new page, which can
immediately be used by RX buffers in the descriptor ring, is allocated
and DMA mapped.

The time a page needs to spend in the recycle ring before the kernel
has released its page references is based on the number of buffers
that use this page.  As large pages can hold more RX buffers, the RX
recycle ring can be shorter.  This reduces memory usage on POWER
systems, while maintaining the performance gain achieved by recycling
pages, following the driver change to pack more than two RX buffers
into large pages.

When an IOMMU is not present, the recycle ring can be small to reduce
memory usage, since DMA mapping operations are inexpensive.

With a small recycle ring, attempting to refill the descriptor queue
with more buffers than the equivalent size of the recycle ring could
ultimately lead to memory leaks if page entries in the recycle ring
were overwritten.  To prevent this, the check to see if the recycle
ring is full is changed to check if the next entry to be written is
NULL.

[bwh: Combine and rebase several commits so this is complete
 before the following buffer-packing changes.  Remove module
 parameter.]
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:13 +00:00
Ben Hutchings
85740cdf0b sfc: Enable RX DMA scattering where possible
Enable RX DMA scattering iff an RX buffer large enough for the current
MTU will not fit into a single page and the NIC supports DMA
scattering for kernel-mode RX queues.

On Falcon and Siena, the RX_USR_BUF_SIZE field is used as the DMA
limit for both all RX queues with scatter enabled.  Set it to 1824,
matching what Onload uses now.

Maintain a statistic for frames truncated due to lack of descriptors
(rx_nodesc_trunc).  This is distinct from rx_frm_trunc which may be
incremented when scattering is disabled and implies an over-length
frame.

Whenever an MTU change causes scattering to be turned on or off,
update filters that point to the PF queues, but leave others
unchanged, as VF drivers assume scattering is off.

Add n_frags parameters to various functions, and make them iterate:
- efx_rx_packet()
- efx_recycle_rx_buffers()
- efx_rx_mk_skb()
- efx_rx_deliver()

Make efx_handle_rx_event() responsible for updating
efx_rx_queue::removed_count.

Change the RX pipeline state to a starting ring index and number of
fragments, and make __efx_rx_packet() responsible for clearing it.

Based on earlier versions by David Riddoch and Jon Cooper.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:12 +00:00
Ben Hutchings
b74e3e8cd6 sfc: Update RX buffer address together with length
Adjust rx_buf->page_offset when we eat the RX hash prefix.  Remove
efx_rx_buf_offset(), which is now redundant.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:11 +00:00
Ben Hutchings
5036b7c7b9 sfc: Explicitly prefetch RX hash prefix, not just Ethernet heade
Currently we prefetch from the Ethernet header, but we will also read
the hash prefix.  In practice they should be in the same cache line
and this won't hurt, but it is still pointless to add on the hash
prefix size.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:10 +00:00
Ben Hutchings
b184f16b7f sfc: Replace efx_rx_buf_eh() with simpler efx_rx_buf_va()
efx_rx_buf_va() returns the virtual address of the current start of
the buffer.  The callers must add the hash prefix size themselves.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:09 +00:00
Ben Hutchings
ff734ef4bc sfc: Wrap __efx_rx_packet() with efx_rx_flush_packet()
The pipeline mechanism will need to change a bit for scattered
packets.  Add a wrapper to insulate efx_process_channel() from this.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:08 +00:00
Ben Hutchings
272baeeb6a sfc: Properly distinguish RX buffer and DMA lengths
Replace efx_nic::rx_buffer_len with efx_nic::rx_dma_len, the maximum
RX DMA length.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:22:06 +00:00
Alexandre Rames
97d48a10c6 sfc: Remove rx_alloc_method SKB
[bwh: Remove more dead code, and make efx_ptp_rx() pull the data it
 needs into the header area.]
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:21:57 +00:00
Ben Hutchings
4a74dc65e3 sfc: Allow efx_channel_type::receive_skb() to reject a packet
Instead of having efx_ptp_rx() call netif_receive_skb() for an invalid
PTP packet, make it return false for rejected packets and have
efx_rx_deliver() pass them up.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-07 20:21:54 +00:00
Ben Hutchings
c73e787a8d sfc: Correct efx_rx_buffer::page_offset when EFX_PAGE_IP_ALIGN != 0
RX DMA buffers start at an offset of EFX_PAGE_IP_ALIGN bytes from the
start of a cache line.  This offset obviously needs to be included in
the virtual address, but this was missed in commit b590ace09d
('sfc: Fix efx_rx_buf_offset() in the presence of swiotlb') since
EFX_PAGE_IP_ALIGN is equal to 0 on both x86 and powerpc.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-03-06 17:57:25 +00:00
Ben Hutchings
b590ace09d sfc: Fix efx_rx_buf_offset() in the presence of swiotlb
We assume that the mapping between DMA and virtual addresses is done
on whole pages, so we can find the page offset of an RX buffer using
the lower bits of the DMA address.  However, swiotlb maps in units of
2K, breaking this assumption.

Add an explicit page_offset field to struct efx_rx_buffer.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-02-26 14:57:16 +00:00
Ben Hutchings
3a68f19d7a sfc: Properly sync RX DMA buffer when it is not the last in the page
We may currently allocate two RX DMA buffers to a page, and only unmap
the page when the second is completed.  We do not sync the first RX
buffer to be completed; this can result in packet loss or corruption
if the last RX buffer completed in a NAPI poll is the first in a page
and is not DMA-coherent.  (In the middle of a NAPI poll, we will
handle the following RX completion and unmap the page *before* looking
at the content of the first buffer.)

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2013-02-26 14:55:49 +00:00
Ben Hutchings
b8e0251730 sfc: Delete redundant page_addr variable from efx_init_rx_buffers_page()
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-12-01 00:26:10 +00:00
Stuart Hodgson
c31e5f9f97 sfc: Add channel specific receive_skb handler and post_remove callback
Allows an extra channel to override the standard receive_skb handler
and also for extra non generic operations to be performed on remove.

Also set default rx strategy so only skbs can be delivered to the
PTP receive function.

Signed-off-by: Stuart Hodgson <smhodgson@solarflare.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-09-07 21:13:39 +01:00
Stuart Hodgson
79d68b3700 sfc: Add explicit RX queue flag to channel
The PTP channel will have its own RX queue even though it's not
a regular traffic channel.

Original work by Ben Hutchings <bhutchings@solarflare.com>

Signed-off-by: Stuart Hodgson <smhodgson@solarflare.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-09-07 21:13:38 +01:00
David S. Miller
54399a78c9 Merge branch 'for-davem' of git://git.kernel.org/pub/scm/linux/kernel/git/bwh/sfc-next
Ben Hutchings says:

====================
1. Fix potential badness when running a self-test with SR-IOV enabled.
2. Fix calculation of some interface statistics that could run backward.
3. Miscellaneous cleanup.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18 09:08:36 -07:00
Ben Hutchings
0e33d87033 sfc: Use generic DMA API, not PCI-DMA API
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-07-17 16:12:30 +01:00
Ben Hutchings
49ce9c2cda drivers/net/ethernet: Fix (nearly-)kernel-doc comments for various functions
Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.  Delete
a few that are content-free.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10 23:13:46 -07:00
David Riddoch
64235187c2 sfc: By default refill RX rings as soon as space for a batch
Previously we refilled with much larger batches, which caused large latency
spikes.  We now have many more much much smaller spikes!

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-05-10 02:22:17 +01:00
David Riddoch
da9ca50582 sfc: Fill RX rings completely full, rather than to 95% full
There was no runtime control of the fast_fill_limit in any case, so purged
that field.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-05-10 02:22:17 +01:00
Ben Hutchings
61321d92fc sfc: Update comments on efx_rx_packet_gro()
The in-tree driver has never supported Driverlink.  The rest of the
comments are rather redundant, but we can usefully state what the
requirements are on the buffer state.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-03-06 18:14:14 +00:00
David S. Miller
ff4783ce78 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/sfc/rx.c

Overlapping changes in drivers/net/ethernet/sfc/rx.c, one to change
the rx_buf->is_page boolean into a set of u16 flags, and another to
adjust how ->ip_summed is initialized.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-26 21:55:51 -05:00
Ben Hutchings
ff3bc1e752 sfc: Fix assignment of ip_summed for pre-allocated skbs
When pre-allocating skbs for received packets, we set ip_summed =
CHECKSUM_UNNCESSARY.  We used to change it back to CHECKSUM_NONE when
the received packet had an incorrect checksum or unhandled protocol.

Commit bc8acf2c8c ('drivers/net: avoid
some skb->ip_summed initializations') mistakenly replaced the latter
assignment with a DEBUG-only assertion that ip_summed ==
CHECKSUM_NONE.  This assertion is always false, but it seems no-one
has exercised this code path in a DEBUG build.

Fix this by moving our assignment of CHECKSUM_UNNECESSARY into
efx_rx_packet_gro().

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-02-25 00:10:22 +00:00
Ben Hutchings
9f2cb71c2b sfc: Leave interrupts and event queues enabled whenever we can
When SR-IOV is enabled we may receive FLR (Function-Level Reset)
events, associated queue flush events and requests from VF drivers at
any time.  Therefore we need to keep event queues and interrupts
enabled whenever possible.

Currently we stop interrupt-driven event processing before flushing RX
and TX queues; efx_nic_flush_queues() then polls event queues for
flush events and discards any others it finds.  Change it to work with
the regular event handling functions.

Currently efx_start_channel() fills RX queues synchronously when a
device is brought up.  This could now race with NAPI, so change it to
send fill events.

This was almost entirely written by Steve Hodgson, formerly
shodgson@solarflare.com.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-02-16 00:24:46 +00:00
Ben Hutchings
2ae75dac30 sfc: Generate RX fill events based on RX queues, not channels
This makes it harder to accidentally send such events to TX-only
channels.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-02-16 00:15:03 +00:00
Ben Hutchings
06e63c57ac sfc: Use a more sensible cast in efx_rx_buf_offset()
This function returns the page offset of the buffer, which can be
calculated based on either its DMA address or its virtual address.  It
used to use the virtual address and we would cast that to unsigned
long, as anything smaller would result in a compiler warning.  Now
that it's using the DMA address we should use unsigned int, matching
the return type.  It is also unnecessary to use __force.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-01-30 16:58:45 +00:00
Ben Hutchings
db3395697c sfc: Replace efx_rx_buffer::is_page and other booleans with a flags field
Replace checksummed and discard booleans from efx_handle_rx_event()
with a bitmask, added to the flags field.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-01-27 00:11:00 +00:00
Ben Hutchings
1ddceb4c69 sfc: Move the end of the non-GRO RX path into its own function
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-01-27 00:11:00 +00:00
Ben Hutchings
0beaca2ca0 sfc: Remove parentheses around return expressions, reported by checkpatch
Fix the following error:

ERROR: return is not a function, parentheses are not required

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-01-05 18:54:04 +00:00