If the allocation of a linear (physically continuous) MPWQE fails,
we allocate a fragmented MPWQE.
This is implemented via device's UMR (User Memory Registration)
which allows to register multiple memory fragments into ConnectX
hardware as a continuous buffer.
UMR registration is an asynchronous operation and is done via
ICO SQs.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Added ICO (Internal Control Operations) SQ per channel to be used
for driver internal operations such as memory registration for
fragmented memory and nop requests upon ifconfig up.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce the feature of multi-packet WQE (RX Work Queue Element)
referred to as (MPWQE or Striding RQ), in which WQEs are larger
and serve multiple packets each.
Every WQE consists of many strides of the same size, every received
packet is aligned to a beginning of a stride and is written to
consecutive strides within a WQE.
In the regular approach, each regular WQE is big enough to be capable
of serving one received packet of any size up to MTU or 64K in case of
device LRO is enabled, making it very wasteful when dealing with
small packets or device LRO is enabled.
For its flexibility, MPWQE allows a better memory utilization
(implying improvements in CPU utilization and packet rate) as packets
consume strides according to their size, preserving the rest of
the WQE to be available for other packets.
MPWQE default configuration:
Num of WQEs = 16
Strides Per WQE = 2048
Stride Size = 64 byte
The default WQEs memory footprint went from 1024*mtu (~1.5MB) to
16 * 2048 * 64 = 2MB per ring.
However, HW LRO can now be supported at no additional cost in memory
footprint, and hence we turn it on by default and get an even better
performance.
Performance tested on ConnectX4-Lx 50G.
To isolate the feature under test, the numbers below were measured with
HW LRO turned off. We verified that the performance just improves when
LRO is turned back on.
* Netperf single TCP stream:
- BW raised by 10-15% for representative packet sizes:
default, 64B, 1024B, 1478B, 65536B.
* Netperf multi TCP stream:
- No degradation, line rate reached.
* Pktgen: packet rate raised by 2-10% for traffic of different message
sizes: 64B, 128B, 256B, 1024B, and 1500B.
* Pktgen: packet loss in bursts of small messages (64byte),
single stream:
- | num packets | packets loss before | packets loss after
| 2K | ~ 1K | 0
| 8K | ~ 6K | 0
| 16K | ~13K | 0
| 32K | ~28K | 0
| 64K | ~57K | ~24K
As expected as the driver can receive as many small packets (<=64B) as
the number of total strides in the ring (default = 2048 * 16) vs. 1024
(default ring size regardless of packets size) before this feature.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Achiad Shochat <achiad@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for Striding RQ feature, which will need its own
RX handlers.
This patch does not change any functionality.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Achiad Shochat <achiad@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Distribute default RSS table uniformly over the rings of the
close NUMA node, instead of all available channels.
This way we enforce the preference of close rings over far ones.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Connect all netdev RQs to this set of queue counters.
Also, add an "rx_out_of_buffer" counter to ethtool,
which indicates RX packet drops due to lack of receive
buffers.
Signed-off-by: Rana Shahout <ranas@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A queue counter can collect several statistics for one or more
hardware queues (QPs, RQs, etc ..) that the counter is attached to.
For Ethernet it will provide an "out of buffer" counter which
collects the number of all packets that are dropped due to lack
of software buffers.
Here we add device commands to alloc/query/dealloc queue counters.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Rana Shahout <ranas@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:
====================
net: bcmsysport: utilize newer NAPI APIs
These two patches are very analoguous to what was already submitted for
BCMGENET and switch the SYSTEMPORT driver to utilizing __napi_schedule_irqoff()
and napi_complete_done for the RX NAPI context.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
By using napi_complete_done(), we allow fine tuning of
/sys/class/net/ethX/gro_flush_timeout for higher GRO aggregation
efficiency for a Gbit NIC.
Check commit 24d2e4a507 ("tg3: use napi_complete_done()") for details.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Both bcm_sysport_tx_isr() and bcm_sysport_rx_isr() run in hard irq
context, we do not need to block irq again.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Nicolas Dichtel says:
====================
libnl: enhance API to ease 64bit alignment for attribute
Here is a proposal to add more helpers in the libnetlink to manage 64-bit
alignment issues.
Note that this series was only tested on x86 by tweeking
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS and adding some traces.
The first patch adds helpers for 64bit alignment and other patches
use them.
We could also add helpers for nla_put_u64() and its variants if needed.
v1 -> v2:
- remove patch #1
- split patch #2 (now #1 and #2)
- add nla_need_padding_for_64bit()
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for the checksum enabled versions of UDP and GRE
tunnels. With this change we should be able to send and receive GSO frames
of these types over the veth pair without needing to segment the packets.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch folds NETIF_F_ALL_TSO into the bitmask for NETIF_F_GSO_SOFTWARE.
The idea is to avoid duplication of defines since the only difference
between the two was the GSO_UDP bit.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We intended to test "err" and not "skb".
Fixes: aed069df09 ('ip_tunnel_core: iptunnel_handle_offloads returns int and doesn't free skb')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Removed .type field from NLA to do proper length checking.
Reported by Daniel Borkmann and Julia Lawall.
Signed-off-by: Peter Heise <peter.heise@airbus.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
EXPIRES_IN_MS macro comes from net/ipv4/inet_diag.c and dates
back to before jiffies_to_msecs() has been introduced.
Now we can remove it and use jiffies_to_msecs().
Suggested-by: Jakub Sitnicki <jkbs@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
move trace_call_bpf() into helper function to minimize the size
of perf_trace_*() tracepoint handlers.
text data bss dec hex filename
10541679 5526646 2945024 19013349 1221ee5 vmlinux_before
10509422 5526646 2945024 18981092 121a0e4 vmlinux_after
It may seem that perf_fetch_caller_regs() can also be moved,
but that is incorrect, since ip/sp will be wrong.
bpf+tracepoint performance is not affected, since
perf_swevent_put_recursion_context() is now inlined.
export_symbol_gpl can also be dropped.
No measurable change in normal perf tracepoints.
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Having the tag protocol in dsa_switch_driver for setup time and in
dsa_switch_tree for runtime is enough. Remove dsa_switch's one.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeff Kirsher says:
====================
100GbE Intel Wired LAN Driver Updates 2016-04-20
This series contains updates to fm10k only.
Jacob provides majority of the changes in this series, starting with the
addition of helper functions to reduce code duplication and the amount
of code indentation. Fixed the use or should we say abuse of the ethtool
stats API, which could result in corrupt memory or misleading statistic
output. Added the appropriate rtnl_lock() and rtnl_unlock() to avoid
RCU warnings during AER events. Come to find out, the PTP/1588 support
is not working with the current version of switch management software
and possibly never worked, so just remove support for PTP/1588 for now.
Fixed how error responses from the switch manager after a LPORT_MAP
request are handled, originally which were silently being ignored.
Fixed up code documentation to hopefully ease the code and comment
comprehension. Fixed a possible NULL pointer dereference after a
kcalloc(), where when writing a new default redirection table, and we
needed to populate a new RSS table using ethtool_rxfh_indir_default().
We populate this table into a region of memory allocated using kcalloc()
but never check it for NULL.
Alex adds support for bulk transmit cleanup for fm10k, like he did for
all of our other drivers.
Ngai-Mint fixes a number of issues with the unicast and multicast address
syncs. Where an issue would occur when the netdev is pre-configured to
either multicast mode and is enabled for the first time.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Check for and handle IPv6 extended headers so that Tx checksum offload
can be done. Also use skb_checksum_help for unexpected cases. This was
originally discovered in ixgbe.
Reported-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Update every header file and other locations to consistently use
Intel(R) instead of just Intel. Also update copyright year of files
which we modified.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
When writing a new default redirection table, we needed to populate
a new RSS table using ethtool_rxfh_indir_default. We populated this
table into a region of memory allocated using kcalloc, but never checked
this for NULL. Fix this by moving the default table generation into
fm10k_write_reta. If this function is passed a table, use it. Otherwise,
generate the default table using ethtool_rxfh_indir_default, 4 at at
time.
Fixes: 0ea7fae440 ("fm10k: use ethtool_rxfh_indir_default for default redirection table")
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Deleting lport when multicast mode is configured to
FM10K_XCAST_MODE_ALLMULTI or FM10K_XCAST_MODE_PROMISC will result in
generating orphaned multicast-group entries in the switch manager.
Before deleting the lport, reset multicast mode to FM10K_XCAST_MODE_NONE
to flush out these multicast-group entries.
Signed-off-by: Ngai-Mint Kwan <ngai-mint.kwan@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The original comment may be read incorrectly as referring to checking
the *entire* length is zero. However, it merely checks only the reserved
bits of both length and reserved in a small amount of code. Update the
comment to indicate this is a clever trick and clearly spell out that it
only checks the reserve bits.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Use a new #define FM10K_VLAN_OVERRIDE even though we're using the exact
same bit. The reason for this is clarity in the code, otherwise you can
read FM10K_VLAN_CLEAR and think it should be removed. Also add a comment
explaining why the FM10K_VLAN_OVERRIDE bit is set.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The diagram represents bit layout of the multi-bit VLAN update message
format. Typically these diagrams are drawn using some power of 2 as the
base, to more easily grasp where fields split. Although the numbers
above can make it somewhat easy to understand which bit you're looking
at, it makes the break points not line up. Re-draw the numbers using
base 8, and mark the bit values every 8 bits at the top. This should
make it more easy to grasp the table quickly.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
fm10k_tlv_parse_attr is supposed to return FM10K_NOT_IMPLEMENTED for any
TLV who's attribute id lies outside the range of results. It does not do
this today. In addition, the documentation does not indicate that other
attributes which are not implemented for a given TLV will be silently
ignored. Fix this. Clean up the logic so that we don't rely on the fact
that FM10K_NOT_IMPLEMENTED is greater than zero, as this can easily
cause confusion.
A future extension could look into some way of reporting unknown TLVs
in order to make issues more easily discoverable. We can't just return
FM10K_NOT_IMPLEMENTED here because we don't want to drop the entire
message if it has an unknown TLV.
While here, update the copyright year.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
fm10k_io_error_detected() does not need to call pci_disable_device(). In
the cases where the reset needs to occur, the stack flow will result in
calling fm10k_remove() which already disables the PCI device. If we
leave the pci_disable_device(), we result in a warning about disabling
an already disabled device.
Many PCI drivers do call pci_disable_device() in their .error_detected()
routines, but it does not appear to be required. In addition, these
drivers have a check "is_pci_enabled()" call in their remove routines,
which is how they chose to handle the duplicate device disable.
This seems incorrect, since the PCI device structure is reference
counted. It is very possible that the reference count for the PCI device
could be greater than 1. In this case, you would remove the PCI device
within the error_detected routine, reducing count to 1, then remove it
again in the remove function, reducing it to zero. This would result in
yet another disable somewhere else failing. Thus, we shouldn't be using
is_pci_enabled() to check for this issue. Instead, just remove the
extraneous pci_device_disable() found within the error_detected routine.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Currently, any error responses from the switch manager after an
LPORT_MAP request are silently ignored. At most the mailbox message will
be reported as an error. This can result in unexpected behavior when the
switch manager has configured a port with zero bandwidth. Add support
for reading the fm10k_swapi_error structure from LPORT_MAP responses.
If the message contains the necessary TLV and has a non-zero error code,
report link down, clear the dglort_map, and delay the next
get_host_state call by a reasonable delay. Also log an error message
indicating that the LPORT_MAP request failed.
The delay ensures preventing an interrupt storm on the switch manager,
and reduces the number of mailbox messages we send in this scenario
drastically.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Multicast mode checking is no longer a requirement to perform unicast
and multicast address syncs. Specifically, a device operating in
promiscuous and/or all multicast mode is not excluded. The issue occurs
when the netdev is pre-configured to either multicast mode and is
enabled for the first time. The multicast-group table in the Switch
Manager will be missing obvious multicast entries associated to this
netdev.
Changes were also made to disallow unicast and multicast syncs with
VLAN 0. The Switch Manager considers VLAN 0 to be an invalid entry.
Requests with VLAN 0 by the netdev are only generated when the driver is
freshly installed and the default VID is not set.
Signed-off-by: Ngai-Mint Kwan <ngai-mint.kwan@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The 1588 support within fm10k does not work correctly with the current
version of the switch management software, and likely never worked
correctly to begin with. Remove support for PTP/1588. Update copyright
year for all these files while we're touching them.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
During an AER action response, we were calling fm10k_close without
holding the rtnl_lock() which could lead to possible RCU warnings being
produced due to 64bit stat updates among other causes. Similarly, we
need rtnl_lock() around fm10k_open during fm10k_io_resume. Follow the
same pattern elsewhere in the driver and protect the entire open/close
sequence.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Use DRV_SUMMARY, similar to DRV_VERSION so that we don't have to
duplicate the driver summary in multiple places.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This patch enables bulk free in Tx cleanup for fm10k and cleans up the
boolean logic in the polling routines for fm10k in the hopes of avoiding
any mix-ups similar to what occurred with i40e and i40evf.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change fixes an (ab)use of the ethtool stats API, which could
result in corrupt memory or misleading stat output. The ethtool stats
API is not robust enough to handle varying number of statistics due to
how it requests the size and allocates memory. Remove the poorly conceived
support originally added for extra debug statistics. In the future,
a new stats API may open up the ability to display these statistics.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Reduce duplicate code and the amount of indentation by adding
fm10k_add_stat_strings and fm10k_add_ethtool_stats functions which help
add fm10k_stat structures to the ethtool stats callbacks. This helps
increase ease of use for future stat additions, and increases code
readability.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This patch adds a new RTM_GETSTATS message to query link stats via netlink
from the kernel. RTM_NEWLINK also dumps stats today, but RTM_NEWLINK
returns a lot more than just stats and is expensive in some cases when
frequent polling for stats from userspace is a common operation.
RTM_GETSTATS is an attempt to provide a light weight netlink message
to explicity query only link stats from the kernel on an interface.
The idea is to also keep it extensible so that new kinds of stats can be
added to it in the future.
This patch adds the following attribute for NETDEV stats:
struct nla_policy ifla_stats_policy[IFLA_STATS_MAX + 1] = {
[IFLA_STATS_LINK_64] = { .len = sizeof(struct rtnl_link_stats64) },
};
Like any other rtnetlink message, RTM_GETSTATS can be used to get stats of
a single interface or all interfaces with NLM_F_DUMP.
Future possible new types of stat attributes:
link af stats:
- IFLA_STATS_LINK_IPV6 (nested. for ipv6 stats)
- IFLA_STATS_LINK_MPLS (nested. for mpls/mdev stats)
extended stats:
- IFLA_STATS_LINK_EXTENDED (nested. extended software netdev stats like bridge,
vlan, vxlan etc)
- IFLA_STATS_LINK_HW_EXTENDED (nested. extended hardware stats which are
available via ethtool today)
This patch also declares a filter mask for all stat attributes.
User has to provide a mask of stats attributes to query. filter mask
can be specified in the new hdr 'struct if_stats_msg' for stats messages.
Other important field in the header is the ifindex.
This api can also include attributes for global stats (eg tcp) in the future.
When global stats are included in a stats msg, the ifindex in the header
must be zero. A single stats message cannot contain both global and
netdev specific stats. To easily distinguish them, netdev specific stat
attributes name are prefixed with IFLA_STATS_LINK_
Without any attributes in the filter_mask, no stats will be returned.
This patch has been tested with mofified iproute2 ifstat.
Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Netlink messages are appended, one object at a time, to the end of
the SKB. Therefore we need to test skb_tail_pointer() not skb->data
for alignment.
Fixes: 35c5845957 ("net: Add helpers for 64-bit aligning netlink attributes.")
Signed-off-by: David S. Miller <davem@davemloft.net>
HAVE_EFFICIENT_UNALIGNED_ACCESS needs CONFIG_ prefix.
Also add a comment in nla_align_64bit() explaining we have
to add a padding if current skb->data is aligned, as it
certainly can be confusing.
Fixes: 35c5845957 ("net: Add helpers for 64-bit aligning netlink attributes.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
New field (IFLA_HSR_VERSION) was added in the middle of an existing
ENUM and would break kernel ABI, therefore moved to the end.
Reported by Stephen Hemminger.
Signed-off-by: Peter Heise <peter.heise@airbus.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The dsa_slave_priv structure does not need a pointer to its net_device.
Kill it.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
BPF updates
This minor set adds a new helper bpf_event_output() for eBPF cls/act
program types which allows to pass events to user space applications.
For details, please see individual patches.
v1 -> v2:
- Address kbuild bot found compile issue in patch 2
- Rest as is
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new helper for cls/act programs that can push events
to user space applications. For networking, this can be f.e. for sampling,
debugging, logging purposes or pushing of arbitrary wake-up events. The
idea is similar to a43eec3042 ("bpf: introduce bpf_perf_event_output()
helper") and 39111695b1 ("samples: bpf: add bpf_perf_event_output example").
The eBPF program utilizes a perf event array map that user space populates
with fds from perf_event_open(), the eBPF program calls into the helper
f.e. as skb_event_output(skb, &my_map, BPF_F_CURRENT_CPU, raw, sizeof(raw))
so that the raw data is pushed into the fd f.e. at the map index of the
current CPU.
User space can poll/mmap/etc on this and has a data channel for receiving
events that can be post-processed. The nice thing is that since the eBPF
program and user space application making use of it are tightly coupled,
they can define their own arbitrary raw data format and what/when they
want to push.
While f.e. packet headers could be one part of the meta data that is being
pushed, this is not a substitute for things like packet sockets as whole
packet is not being pushed and push is only done in a single direction.
Intention is more of a generically usable, efficient event pipe to applications.
Workflow is that tc can pin the map and applications can attach themselves
e.g. after cls/act setup to one or multiple map slots, demuxing is done by
the eBPF program.
Adding this facility is with minimal effort, it reuses the helper
introduced in a43eec3042 ("bpf: introduce bpf_perf_event_output() helper")
and we get its functionality for free by overloading its BPF_FUNC_ identifier
for cls/act programs, ctx is currently unused, but will be made use of in
future. Example will be added to iproute2's BPF example files.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a BPF_F_CURRENT_CPU flag to optimize the use-case where user space has
per-CPU ring buffers and the eBPF program pushes the data into the current
CPU's ring buffer which saves us an extra helper function call in eBPF.
Also, make sure to properly reserve the remaining flags which are not used.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add __init attribute on a function that is only called from other __init
functions and that is not inlined, at least with gcc version 4.8.4 on an
x86 machine with allyesconfig. Currently, the function is put in the
.text.unlikely segment. Declaring it as __init will cause it to be put in
the .init.text and to disappear after initialization.
The result of objdump -x on the function before the change is as follows:
0000000000000000 l F .text.unlikely 00000000000000bf check_mirror
And after the change it is as follows:
0000000000000000 l F .init.text 00000000000000ba check_mirror
Done with the help of Coccinelle. The semantic patch checks for local
static non-init functions that are called from an __init function and are
not called from any other function.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Michael Grzeschik <mgr@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Separated from previous patch for readability.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
