100 Commits

Author SHA1 Message Date
Olivier Matz
cbc12b0a96 mk: do not generate LDLIBS from directory dependencies
The list of libraries in LDLIBS was generated from the DEPDIRS-xyz
variable. This is valid when the subdirectory name match the library
name, but it's not always the case, especially for PMDs.

The patches removes this feature and explicitly adds the proper
libraries in LDLIBS.

Some DEPDIRS-xyz variables become useless, remove them.

Reported-by: Gage Eads <gage.eads@intel.com>
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Gage Eads <gage.eads@intel.com>
2017-10-24 02:14:57 +02:00
Matan Azrad
d5b0924ba6 ethdev: add return value to stats get dev op
The stats_get dev op API doesn't include return value, so PMD cannot
return an error in case of failure at stats getting process time.

Since PCI devices can be removed and there is a time between the
physical removal to the RMV interrupt, the user may get invalid stats
without any indication.

This patch changes the stats_get API return value to be int instead of
void.

All the net PMDs stats_get dev ops are adjusted by this patch.

Signed-off-by: Matan Azrad <matan@mellanox.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2017-10-12 01:52:49 +01:00
Zhiyong Yang
f8244c6399 ethdev: increase port id range
Extend port_id definition from uint8_t to uint16_t in lib and drivers
data structures, specifically rte_eth_dev_data. Modify the APIs,
drivers and app using port_id at the same time.

Fix some checkpatch issues from the original code and remove some
unnecessary cast operations.

release_17_11 and deprecation docs have been updated in this patch.

Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2017-10-06 18:23:25 +02:00
Alejandro Lucero
edbe47001e net/nfp: write PF MAC to config BAR
VFs rely on config BAR for getting the MAC address, although a
random one is created a valid address is not found.

A PF port has a fixed MAC which is currently acquired using the NSPU
interface. Some NFP firmwares require the MAC being writing back
to the config BAR for doing proper MAC filtering.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
517e9c26ff net/nfp: configure capabilities by default
These capabilities are enabled in current NFP firmwares by
default, but it could be they are not with NFP firmwares to come.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
c05dc84fa2 net/nfp: configure L2 broadcast and multicast
This is required in some NFP firmwares when working with VFs.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
a9f0220476 net/nfp: remove firmware ABI check
Link speed is not advertised in old firmwares. However, it is safe
to remove the check because reading NFP_NET_CFG_STS returns 0 in
those cases.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
f00351f88d net/nfp: add info about RSS capabilities
NFP supports RSS but it is not being advertised.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
ad60bca348 net/nfp: read PF port MAC addr using NSP
During initialization, mac address is read from configuration bar. This is
the default option when using VFs.

This patch adds support for reading the mac address using the NSPU
interface when PMD works with the PF.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
c95c8c8b60 net/nfp: support HW port link configuration
PMD has to configure the hardware port: link up when port started and
link down when port stopped. This is not required for VFs but it is
for PF ports.

A minor refactoring in PMD stop and close functions is done because the
Link down needs to happen just when device is stopped.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
48e2255f1b net/nfp: add NSP support for HW link configuration
Adding a new NSPU command for being able to read and write the ethernet
port table from/to the NFP. This will allow the PMD to put the Link up
or down when a port is started or stopped. Until now, this was performed
by the firmware independently of PMD functionality.

The ethernet port table has also some other useful information that will
be used in further commits.

Usually NSPU is used at device probe time and that is sequential code
execution. However, reading and writing the NFP eth table can be done at
different times and from different cores, and it implies it could happen
a concurrent access. A spinlock is added to the global nspu object for
protecting the NFP and avoiding the concurrent access.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
c4171b520b net/nfp: support PF multiport
A NFP PF PCI device can have several physical ports, up to 8. Because
DPDK core creates one eth_dev per PCI device, nfp pf probe function
is used. Number of PF ports is obtained from firmware symbol using
NSPU API. Inside PF probe function an eth_dev per port is created and
nfp_net_init invoked for each port.

There are some limitations regarding multiport: rx interrupts and
device hotplug are not supported.

Interrupts are handled with the VFIO or UIO drivers help. Those
drivers just know about PCI devices, so it is not possible, without
changing how DPDK handles interrupts, manage interrupts assigned to
different PF ports.

About hotplug, the problem is this functionality is based on a PCI
device, and although device plugin is possible, which would add as
many ports as supported by firmware, unplug is based on device name
linked to a eth_dev, and device name has a suffix now (_portX, with X
being the port index) which DPDK core is not aware of. While rx
interrupts with multiport could be likely solved with some layer of
indirection, hotplug would require changes to DPDK core.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
a75b4086aa net/nfp: allocate ethernet device from PF probe function
NFP can support several physical ports per PF device. Depending on
firmware info, one or more eth_dev objects will need to be created.

This patch adds the call to create just one eth_dev by now with future
commits supporting the multiport option. Once the eth_dev has been
created, probe function invokes pmd initialization with the new eth_dev.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
5971973d7d net/nfp: support PF devices inside PMD initialization
nfp_net_init is where a dpdk port related to a eth_dev is initialized.
NFP VF vNICs use VF PCI BARs as they come after SRIOV is enabled. But for
NFP PF vNIC just a subset of PF PCI BARs are used.

This patch adds support for mapping the right PCI BAR subsets for the PF
vNIC. It uses the NSPU API functions introduced previously for configuring
NFP expansion bars.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
d054146599 net/nfp: support vNIC Rx/Tx BAR mappings
NFP vNICs use a subset of PCI device BARs. vNIC rx/tx bars point to
NFP hardware queues unit. Unlike vNIC config bar, the NFP address is
always the same so the NFP expansion bar configuration always uses
the same hardcoded physical address.

This patch adds a NSPU API function for getting vNIC rx/tx bars
mapped through a expansion bar using that specific physical address.

The PMD will use the PCI bar offset returned for mapping the vNIC
rx/tx bars.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
6b2e61ac36 net/nfp: support vNIC config BAR mapping
NFP vNICs use a subset of PCI device BARs. vNIC config bar depends on
firmware symbol defining how to map it through a NFP expansion bar.

This patch adds a NSPU API function for getting a vNIC config bar
mapped through a expansion bar giving a firmware symbol. The PMD will
use the PCI bar offset returned for accessing the vNIC bar.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
1e37fb52c6 net/nfp: add FW upload logic
PMD will use this function for uploading the firmware. First, a
symbol resolution is done for finding out if there is a firmware
already there. If not, a NFP reset is called before using NSPU
fw upload code.

PMD PF probe function is now using this logic.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
dd63df2bff net/nfp: add NSP symbol resolution command
Firmware has symbols helping to configure things like number of
PF ports, vNIC BARs addresses inside NFP memories, or ethernet
link state. Different firmware apps have different things to map
and likely different internal NFP addresses to use.

Host drivers can use the NSPU interface for getting symbol data
regarding different hardware configurations. Once the driver has
the information about a specific object, a mapping is required
configuring an NFP expansion bar creating a device PCI bar window.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
f37d8a4b67 net/nfp: add NSP FW upload command
Using NSPU interface for fw upload. Firmware file needs to be
installed in specific path inside system firmware directory.

NSPU buffer is used for writing the firmware before sending the
command.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
225f6b3359 net/nfp: add NSP support for commands
NSPU interface declares a buffer controlled by the NFP NSP service
processor. It is possible to send commands to the NSP using the NSPU
and this buffer for data related to the command. A command can imply
buffer read, buffer write, both or none.

Initial command for resetting the firmware is added as well which
does not require the buffer at all.

Commands will allow firmware upload, symbol resolution and ethernet
link configuration. Future commands will allow specific offloads like
flow offloads and eBPF offload.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
35422e4e05 net/nfp: support new PCI id
A NFP PF PCI devices can have PCI ID 4000 or 6000.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
68086b3f68 net/nfp: add specific PF probe function
Configuring the NFP PMD for using the PF requires access through the
NSPU interface for device configuration. This patch adds a specific probe
function for the PF which uses the NSPU interface. Just basic NSPU access
is done by now reading the NSPU ABI version.

NSPU ABI version needs to be greater than 0.19.

No ethernet port is created yet.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
d12206e005 net/nfp: add NSP user space interface
Working with the PF requires access to the NFP for basic configuration.
NSP is the NFP Service Processor helping with hardware and firmware
configuration. NSPU is the NSP user space interface for working with the
NSP.

Configuration through NSPU allows to create PCI BAR windows for accessing
different NFP hardware units, including the BAR window for the NSPU
interface access itself. NFP expansion bar registers are used for creating
those PCI BAR windows. NSPU uses a specific expansion bar which is
reprogrammed for accessing/doing different things.

Other expansion bars will be configured later for configuring the PF vNIC
bars, a subset of PF PCI BARs.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:48 +02:00
Alejandro Lucero
1d5d4ab903 net/nfp: support new firmware medatada API
We need to support how firmware metadata was handled until now and also
the new API, since NFP NFD 3.0 firmware versions. The new metadata API
adds flexibility for working with different metadata types and, mainly,
to allow adding metadata from different firmware components independently.

Although this patch just supports one type handled by the PMD, future uses
regarding firmware apps will extend this support.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:47 +02:00
Alejandro Lucero
f78f0e64f7 net/nfp: handle packets with length 0 as usual ones
A DPDK app could, whatever the reason, send packets with size 0.
The PMD is not sending those packets, which does make sense,
but the problem is the mbuf is not released either. That leads
to mbufs not being available, because the app trusts the
PMD will do it.

Although this is a problem related to app wrong behavior, we
should harden the PMD in this regard. Not sending a packet with
size 0 could be problematic, needing special handling inside the
PMD xmit function. It could be a burst of those packets, which can
be easily handled, but it could also be a single packet in a burst,
what is harder to handle.

It would be simpler to just send that kind of packets, which will
likely be dropped by the hw at some point. The main problem is how
the fw/hw handles the DMA, because a dma read to a hypothetical 0x0
address could trigger an IOMMU error. It turns out, it is safe to
send a descriptor with packet size 0 to the hardware: the DMA never
happens, from the PCIe point of view.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:47 +02:00
Alejandro Lucero
7dcb19d78f net/nfp: fix Rx interrupt when multiqueue
intr_vec was not properly configured. This is not a problem when
just one queue is supported but it fails with multiqueue.

Some minor refactoring also done for hardware interrupt configuration.

Fixes: ea121b28316d ("net/nfp: add Rx interrupts")
Cc: stable@dpdk.org

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:47 +02:00
Alejandro Lucero
e1102e36fa net/nfp: fix RSS
Redirection table was not being updated properly.
There is also a problem when configuring RSS.

Fixes: 934e4c60fbff ("nfp: add RSS")
Cc: stable@dpdk.org

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:47 +02:00
Alejandro Lucero
f08d93d4d8 net/nfp: write MAC address to configuration bar
If not a valid mac present in configuration bar, PMD creates a random
one. It needs to be passed to the NIC.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-10-06 02:49:47 +02:00
Olivier Matz
fed524ce53 eal: introduce integer log2 function
At some places, the log2() function is used despite this function
works on float. This introduces a dependency to the math lib but
most of the time it is not required because we want an integer log2.

Add a new helper to do this job and fix nfp driver.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-07-03 10:44:12 +02:00
Bernard Iremonger
d6af1a13d7 ethdev: add return values to callback process API
Change the rte_eth_dev_callback_process function to return int,
and add a void *ret_param parameter.
The new parameter is used by ixgbe and i40e instead of abusing
the user data of the callback.

Signed-off-by: Bernard Iremonger <bernard.iremonger@intel.com>
2017-07-01 17:19:55 +02:00
Jerin Jacob
98a7ea332b fix typos using codespell utility
Fixing typos across dpdk source code using codespell utility.
Skipped the ethdev driver's base code fixes to keep the base
code intact.

Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: John McNamara <john.mcnamara@intel.com>
2017-06-14 23:54:13 +02:00
Ferruh Yigit
c0802544d9 drivers/net: add generic ethdev macro to get PCI device
Instead of many PMD define their own macro, define a generic one in
ethdev and use that in PMDs.

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Allain Legacy <allain.legacy@windriver.com>
Acked-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
Acked-by: Andrew Rybchenko <arybchenko@solarflare.com>
2017-06-12 10:41:25 +01:00
David Marchand
06e81dc9b7 drivers/net: fix vfio kmod dependency
vfio is the kernel framework used by the vfio-pci kernel driver.
DPDK drivers do not rely solely on vfio, but rather on vfio-pci to gain
access to pci resources.

Fixes: 0880c40113ef ("drivers: advertise kmod dependencies in pmdinfo")
Cc: stable@dpdk.org

Signed-off-by: David Marchand <david.marchand@6wind.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
2017-06-05 20:56:54 +02:00
Alejandro Lucero
aaef1010af net/nfp: fix releasing muti-segment mbufs
If segments are used, just mbufs previously linked to head descriptor
of a mbuf chain are released. Other Tx descriptor are used for the
mbuf chain but they keep their linked mbufs without releasing them.

It is not a fatal issue because sooner or later those descriptors will
be head descriptors or just used for a single mbuf packet, then those
linked mbufs will be released.

However, this leads to apps needing bigger mbufs pools and some
confusion about memory requirements. Indeed, because larger pools, some
performance impact could also be expected due to cache misses.

With this patch all Tx descriptors will release linked mbufs inside the
xmit function, and rte_pktmbuf_seg_free is used instead of
rte_pktmbuf_free.

Fixes: 142854c62134 ("nfp: fix freeing multi-mbuf packets")
Cc: stable@dpdk.org

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-04-28 14:46:18 +02:00
Jan Blunck
fdf91e0f2f drivers/net: do not use ethdev driver
Signed-off-by: Jan Blunck <jblunck@infradead.org>
Signed-off-by: Gaetan Rivet <gaetan.rivet@6wind.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
2017-04-18 19:05:46 +02:00
Jan Blunck
f02513445e net/nfp: use ethdev DMA helper
This driver can use the library function rte_eth_dma_zone_reserve()
instead of duplicating the code.

Signed-off-by: Jan Blunck <jblunck@infradead.org>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
2017-04-18 19:01:40 +02:00
Qi Zhang
c23a1a3000 eal: clean up interrupt handle
The patch change the prototype of callback function
(rte_intr_callback_fn) by removing the unnecessary parameter.

Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
2017-04-06 21:15:55 +02:00
Alejandro Lucero
5282261298 net/nfp: fix Rx interrupt
Current code enables RX interrupts even if this it not
requested.

Fixes: ea121b28316d ("net/nfp: add Rx interrupts")
Cc: stable@dpdk.org

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-04-04 18:59:45 +02:00
Alejandro Lucero
19ac8c75df net/nfp: fix packet/data length conversion
Chained mbufs hold data_len as the length of that particular mbuf
and pkt_len as the full packet length including all the chained
mbufs. It is not clear from the mbuf definition if pkt_len should
be set for all the mbufs in a chain, but code there for handling
mbufs suggests just the first mbuf requires to have pkt_len set.

NFP PMD was assuming pkt_len is set in all the chained mbufs and
unit tests for gather dma were building mbufs with pkt_len always
set. This patch gets rid of that assumption.

Fixes: b812daadad0d ("nfp: add Rx and Tx")
Cc: stable@dpdk.org

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-04-04 18:59:45 +02:00
Alejandro Lucero
2dfcada3eb net/nfp: clean Tx descriptor flags
When LSO, not doing this can led to firmware disruption. It does
not show as error because TCP ends up sending data again later on.

Fixes: 9ba3d0ae2090 ("net/nfp: add TSO support")
Cc: stable@dpdk.org

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-04-04 18:59:45 +02:00
Olivier Matz
feb9f680cd mk: optimize directory dependencies
Before this patch, the management of dependencies between directories
had several issues:

- the generation of .depdirs, done at configuration is slow: it can take
  more than one minute on some slow targets (usually ~10s on a standard
  PC without -j).

- for instance, it is possible to express a dependency like:
  - app/foo depends on lib/librte_foo
  - and lib/librte_foo depends on app/bar
  But this won't work because the directories are traversed with a
  depth-first algorithm, so we have to choose between doing 'app' before
  or after 'lib'.

- the script depdirs-rule.sh is too complex.

- we cannot use "make -d" for debug, because the output of make is used for
  the generation of .depdirs.

This patch moves the DEPDIRS-* variables in the upper Makefile, making
the dependencies much easier to calculate. A DEPDIRS variable is still
used to process library dependencies in LDLIBS.

After this commit, "make config" is almost immediate.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Tested-by: Robin Jarry <robin.jarry@6wind.com>
Tested-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
2017-03-27 23:28:43 +02:00
Olivier Matz
0ef850c4f6 ethdev: move a queue id check to generic layer
The check of queue_id is done in all drivers implementing
rte_eth_rx_queue_count(). Factorize this check in the generic function.

Note that the nfp driver was doing the check differently, which could
induce crashes if the queue index was too big.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
2017-03-09 19:29:51 +01:00
Jeff Guo
45f4dd1adc drivers/net: fix device configuration
dev_flags is wrongly overwritten with RTE_ETH_DEV_DETACHABLE value
in drivers after rte_eth_copy_pci_info().

Previous values of the dev_flags set in rte_eth_copy_pci_info(),
like RTE_ETH_DEV_INTR_LSC, are get lost. That will fail the device
configuration.

Fix by preventing dev_flags overwritten.

Fixes: 22dda618c00c ("pci: separate detaching ethernet ports from PCI devices")

Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
Signed-off-by: Jeff Guo <jia.guo@intel.com>
2017-02-10 12:25:49 +01:00
Ferruh Yigit
f2462150ec drivers/net: remove redundant new line from logs
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
2017-01-30 22:18:27 +01:00
Ferruh Yigit
28a1fd4fd0 drivers/net: make PCI device id struct const
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Shreyansh Jain <shreyansh.jain@nxp.com>
2017-01-30 22:18:26 +01:00
Santosh Shukla
7b0983c26c net/nfp: use I/O device memory read/write API
Replace the raw I/O device memory read/write access with eal
abstraction for I/O device memory read/write access to fix
portability issues across different architectures.

CC: Alejandro Lucero <alejandro.lucero@netronome.com>
Signed-off-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>
Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-01-18 17:18:27 +01:00
Olivier Matz
6ffc32808d net/nfp: fix VLAN offload flags check
Fix typo when checking that no VLAN offload flags are passed at port
initialization.

By the way, also fix a typo in the log.

Fixes: d4a27a3b092a ("nfp: add basic features")

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-01-17 19:41:42 +01:00
Alejandro Lucero
9ba3d0ae20 net/nfp: add TSO support
This patch implements NFP PMD support for TSO but it also requires
a firmware advertising the capability.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-01-17 19:40:52 +01:00
Alejandro Lucero
ea121b2831 net/nfp: add Rx interrupts
This is supported with UIO and VFIO modules. With UIO, LSC interrupt
is disabled.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-01-17 19:40:52 +01:00
Alejandro Lucero
74a640dac8 net/nfp: avoid modulo operations for handling ring wrapping
Having those modulo operations implies costly instructions execution,
what can be avoided with conditionals and unlikely clauses.

This change makes the software ring read and write indexes to be now
always within the ring size which has to be handled properly. The main
problem is when write pointer wraps and being less than the read pointer.
This happened before, but just with indexes type size (uint32_t) wrapping,
and in that case the processor does the right thing no requiring special
handling by software.

This work has also led to discovering redundant pointers in the driver,
which have been removed.

Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
2017-01-17 19:40:52 +01:00