Daniel Borkmann [Fri, 26 Sep 2014 20:37:36 +0000 (22:37 +0200)]
net: tcp: add DCTCP congestion control algorithm
This work adds the DataCenter TCP (DCTCP) congestion control
algorithm [1], which has been first published at SIGCOMM 2010 [2],
resp. follow-up analysis at SIGMETRICS 2011 [3] (and also, more
recently as an informational IETF draft available at [4]).
DCTCP is an enhancement to the TCP congestion control algorithm for
data center networks. Typical data center workloads are i.e.
i) partition/aggregate (queries; bursty, delay sensitive), ii) short
messages e.g. 50KB-1MB (for coordination and control state; delay
sensitive), and iii) large flows e.g. 1MB-100MB (data update;
throughput sensitive). DCTCP has therefore been designed for such
environments to provide/achieve the following three requirements:
* High burst tolerance (incast due to partition/aggregate)
* Low latency (short flows, queries)
* High throughput (continuous data updates, large file
transfers) with commodity, shallow buffered switches
The basic idea of its design consists of two fundamentals: i) on the
switch side, packets are being marked when its internal queue
length > threshold K (K is chosen so that a large enough headroom
for marked traffic is still available in the switch queue); ii) the
sender/host side maintains a moving average of the fraction of marked
packets, so each RTT, F is being updated as follows:
F := X / Y, where X is # of marked ACKs, Y is total # of ACKs
alpha := (1 - g) * alpha + g * F, where g is a smoothing constant
The resulting alpha (iow: probability that switch queue is congested)
is then being used in order to adaptively decrease the congestion
window W:
W := (1 - (alpha / 2)) * W
The means for receiving marked packets resp. marking them on switch
side in DCTCP is the use of ECN.
RFC3168 describes a mechanism for using Explicit Congestion Notification
from the switch for early detection of congestion, rather than waiting
for segment loss to occur.
However, this method only detects the presence of congestion, not
the *extent*. In the presence of mild congestion, it reduces the TCP
congestion window too aggressively and unnecessarily affects the
throughput of long flows [4].
DCTCP, as mentioned, enhances Explicit Congestion Notification (ECN)
processing to estimate the fraction of bytes that encounter congestion,
rather than simply detecting that some congestion has occurred. DCTCP
then scales the TCP congestion window based on this estimate [4],
thus it can derive multibit feedback from the information present in
the single-bit sequence of marks in its control law. And thus act in
*proportion* to the extent of congestion, not its *presence*.
Switches therefore set the Congestion Experienced (CE) codepoint in
packets when internal queue lengths exceed threshold K. Resulting,
DCTCP delivers the same or better throughput than normal TCP, while
using 90% less buffer space.
It was found in [2] that DCTCP enables the applications to handle 10x
the current background traffic, without impacting foreground traffic.
Moreover, a 10x increase in foreground traffic did not cause any
timeouts, and thus largely eliminates TCP incast collapse problems.
The algorithm itself has already seen deployments in large production
data centers since then.
We did a long-term stress-test and analysis in a data center, short
summary of our TCP incast tests with iperf compared to cubic:
This test measured DCTCP throughput and latency and compared it with
CUBIC throughput and latency for an incast scenario. In this test, 19
senders sent at maximum rate to a single receiver. The receiver simply
ran iperf -s.
The senders ran iperf -c <receiver> -t 30. All senders started
simultaneously (using local clocks synchronized by ntp).
This test was repeated multiple times. Below shows the results from a
single test. Other tests are similar. (DCTCP results were extremely
consistent, CUBIC results show some variance induced by the TCP timeouts
that CUBIC encountered.)
For this test, we report statistics on the number of TCP timeouts,
flow throughput, and traffic latency.
1) Timeouts (total over all flows, and per flow summaries):
CUBIC DCTCP
Total 3227 25
Mean 169.842 1.316
Median 183 1
Max 207 5
Min 123 0
Stddev 28.991 1.600
Timeout data is taken by measuring the net change in netstat -s
"other TCP timeouts" reported. As a result, the timeout measurements
above are not restricted to the test traffic, and we believe that it
is likely that all of the "DCTCP timeouts" are actually timeouts for
non-test traffic. We report them nevertheless. CUBIC will also include
some non-test timeouts, but they are drawfed by bona fide test traffic
timeouts for CUBIC. Clearly DCTCP does an excellent job of preventing
TCP timeouts. DCTCP reduces timeouts by at least two orders of
magnitude and may well have eliminated them in this scenario.
2) Throughput (per flow in Mbps):
CUBIC DCTCP
Mean 521.684 521.895
Median 464 523
Max 776 527
Min 403 519
Stddev 105.891 2.601
Fairness 0.962 0.999
Throughput data was simply the average throughput for each flow
reported by iperf. By avoiding TCP timeouts, DCTCP is able to
achieve much better per-flow results. In CUBIC, many flows
experience TCP timeouts which makes flow throughput unpredictable and
unfair. DCTCP, on the other hand, provides very clean predictable
throughput without incurring TCP timeouts. Thus, the standard deviation
of CUBIC throughput is dramatically higher than the standard deviation
of DCTCP throughput.
Mean throughput is nearly identical because even though cubic flows
suffer TCP timeouts, other flows will step in and fill the unused
bandwidth. Note that this test is something of a best case scenario
for incast under CUBIC: it allows other flows to fill in for flows
experiencing a timeout. Under situations where the receiver is issuing
requests and then waiting for all flows to complete, flows cannot fill
in for timed out flows and throughput will drop dramatically.
3) Latency (in ms):
CUBIC DCTCP
Mean 4.0088 0.04219
Median 4.055 0.0395
Max 4.2 0.085
Min 3.32 0.028
Stddev 0.1666 0.01064
Latency for each protocol was computed by running "ping -i 0.2
<receiver>" from a single sender to the receiver during the incast
test. For DCTCP, "ping -Q 0x6 -i 0.2 <receiver>" was used to ensure
that traffic traversed the DCTCP queue and was not dropped when the
queue size was greater than the marking threshold. The summary
statistics above are over all ping metrics measured between the single
sender, receiver pair.
The latency results for this test show a dramatic difference between
CUBIC and DCTCP. CUBIC intentionally overflows the switch buffer
which incurs the maximum queue latency (more buffer memory will lead
to high latency.) DCTCP, on the other hand, deliberately attempts to
keep queue occupancy low. The result is a two orders of magnitude
reduction of latency with DCTCP - even with a switch with relatively
little RAM. Switches with larger amounts of RAM will incur increasing
amounts of latency for CUBIC, but not for DCTCP.
4) Convergence and stability test:
This test measured the time that DCTCP took to fairly redistribute
bandwidth when a new flow commences. It also measured DCTCP's ability
to remain stable at a fair bandwidth distribution. DCTCP is compared
with CUBIC for this test.
At the commencement of this test, a single flow is sending at maximum
rate (near 10 Gbps) to a single receiver. One second after that first
flow commences, a new flow from a distinct server begins sending to
the same receiver as the first flow. After the second flow has sent
data for 10 seconds, the second flow is terminated. The first flow
sends for an additional second. Ideally, the bandwidth would be evenly
shared as soon as the second flow starts, and recover as soon as it
stops.
The results of this test are shown below. Note that the flow bandwidth
for the two flows was measured near the same time, but not
simultaneously.
DCTCP performs nearly perfectly within the measurement limitations
of this test: bandwidth is quickly distributed fairly between the two
flows, remains stable throughout the duration of the test, and
recovers quickly. CUBIC, in contrast, is slow to divide the bandwidth
fairly, and has trouble remaining stable.
CUBIC DCTCP
Seconds Flow 1 Flow 2 Seconds Flow 1 Flow 2
0 9.93 0 0 9.92 0
0.5 9.87 0 0.5 9.86 0
1 8.73 2.25 1 6.46 4.88
1.5 7.29 2.8 1.5 4.9 4.99
2 6.96 3.1 2 4.92 4.94
2.5 6.67 3.34 2.5 4.93 5
3 6.39 3.57 3 4.92 4.99
3.5 6.24 3.75 3.5 4.94 4.74
4 6 3.94 4 5.34 4.71
4.5 5.88 4.09 4.5 4.99 4.97
5 5.27 4.98 5 4.83 5.01
5.5 4.93 5.04 5.5 4.89 4.99
6 4.9 4.99 6 4.92 5.04
6.5 4.93 5.1 6.5 4.91 4.97
7 4.28 5.8 7 4.97 4.97
7.5 4.62 4.91 7.5 4.99 4.82
8 5.05 4.45 8 5.16 4.76
8.5 5.93 4.09 8.5 4.94 4.98
9 5.73 4.2 9 4.92 5.02
9.5 5.62 4.32 9.5 4.87 5.03
10 6.12 3.2 10 4.91 5.01
10.5 6.91 3.11 10.5 4.87 5.04
11 8.48 0 11 8.49 4.94
11.5 9.87 0 11.5 9.9 0
SYN/ACK ECT test:
This test demonstrates the importance of ECT on SYN and SYN-ACK packets
by measuring the connection probability in the presence of competing
flows for a DCTCP connection attempt *without* ECT in the SYN packet.
The test was repeated five times for each number of competing flows.
Competing Flows 1 | 2 | 4 | 8 | 16
------------------------------
Mean Connection Probability 1 | 0.67 | 0.45 | 0.28 | 0
Median Connection Probability 1 | 0.65 | 0.45 | 0.25 | 0
As the number of competing flows moves beyond 1, the connection
probability drops rapidly.
Enabling DCTCP with this patch requires the following steps:
DCTCP must be running both on the sender and receiver side in your
data center, i.e.:
sysctl -w net.ipv4.tcp_congestion_control=dctcp
Also, ECN functionality must be enabled on all switches in your
data center for DCTCP to work. The default ECN marking threshold (K)
heuristic on the switch for DCTCP is e.g., 20 packets (30KB) at
1Gbps, and 65 packets (~100KB) at 10Gbps (K > 1/7 * C * RTT, [4]).
In above tests, for each switch port, traffic was segregated into two
queues. For any packet with a DSCP of 0x01 - or equivalently a TOS of
0x04 - the packet was placed into the DCTCP queue. All other packets
were placed into the default drop-tail queue. For the DCTCP queue,
RED/ECN marking was enabled, here, with a marking threshold of 75 KB.
More details however, we refer you to the paper [2] under section 3).
There are no code changes required to applications running in user
space. DCTCP has been implemented in full *isolation* of the rest of
the TCP code as its own congestion control module, so that it can run
without a need to expose code to the core of the TCP stack, and thus
nothing changes for non-DCTCP users.
Changes in the CA framework code are minimal, and DCTCP algorithm
operates on mechanisms that are already available in most Silicon.
The gain (dctcp_shift_g) is currently a fixed constant (1/16) from
the paper, but we leave the option that it can be chosen carefully
to a different value by the user.
In case DCTCP is being used and ECN support on peer site is off,
DCTCP falls back after 3WHS to operate in normal TCP Reno mode.
ss {-4,-6} -t -i diag interface:
... dctcp wscale:7,7 rto:203 rtt:2.349/0.026 mss:1448 cwnd:2054
ssthresh:1102 ce_state 0 alpha 15 ab_ecn 0 ab_tot 735584
send 10129.2Mbps pacing_rate 20254.1Mbps unacked:1822 retrans:0/15
reordering:101 rcv_space:29200
... dctcp-reno wscale:7,7 rto:201 rtt:0.711/1.327 ato:40 mss:1448
cwnd:10 ssthresh:1102 fallback_mode send 162.9Mbps pacing_rate
325.5Mbps rcv_rtt:1.5 rcv_space:29200
More information about DCTCP can be found in [1-4].
[1] http://simula.stanford.edu/~alizade/Site/DCTCP.html
[2] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf
[3] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf
[4] http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00
Joint work with Florian Westphal and Glenn Judd.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Westphal [Fri, 26 Sep 2014 20:37:35 +0000 (22:37 +0200)]
net: tcp: more detailed ACK events and events for CE marked packets
DataCenter TCP (DCTCP) determines cwnd growth based on ECN information
and ACK properties, e.g. ACK that updates window is treated differently
than DUPACK.
Also DCTCP needs information whether ACK was delayed ACK. Furthermore,
DCTCP also implements a CE state machine that keeps track of CE markings
of incoming packets.
Therefore, extend the congestion control framework to provide these
event types, so that DCTCP can be properly implemented as a normal
congestion algorithm module outside of the core stack.
Joint work with Daniel Borkmann and Glenn Judd.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Westphal [Fri, 26 Sep 2014 20:37:34 +0000 (22:37 +0200)]
net: tcp: split ack slow/fast events from cwnd_event
The congestion control ops "cwnd_event" currently supports
CA_EVENT_FAST_ACK and CA_EVENT_SLOW_ACK events (among others).
Both FAST and SLOW_ACK are only used by Westwood congestion
control algorithm.
This removes both flags from cwnd_event and adds a new
in_ack_event callback for this. The goal is to be able to
provide more detailed information about ACKs, such as whether
ECE flag was set, or whether the ACK resulted in a window
update.
It is required for DataCenter TCP (DCTCP) congestion control
algorithm as it makes a different choice depending on ECE being
set or not.
Joint work with Daniel Borkmann and Glenn Judd.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann [Fri, 26 Sep 2014 20:37:33 +0000 (22:37 +0200)]
net: tcp: add flag for ca to indicate that ECN is required
This patch adds a flag to TCP congestion algorithms that allows
for requesting to mark IPv4/IPv6 sockets with transport as ECN
capable, that is, ECT(0), when required by a congestion algorithm.
It is currently used and needed in DataCenter TCP (DCTCP), as it
requires both peers to assert ECT on all IP packets sent - it
uses ECN feedback (i.e. CE, Congestion Encountered information)
from switches inside the data center to derive feedback to the
end hosts.
Therefore, simply add a new flag to icsk_ca_ops. Note that DCTCP's
algorithm/behaviour slightly diverges from RFC3168, therefore this
is only (!) enabled iff the assigned congestion control ops module
has requested this. By that, we can tightly couple this logic really
only to the provided congestion control ops.
Joint work with Florian Westphal and Glenn Judd.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Westphal [Fri, 26 Sep 2014 20:37:32 +0000 (22:37 +0200)]
net: tcp: assign tcp cong_ops when tcp sk is created
Split assignment and initialization from one into two functions.
This is required by followup patches that add Datacenter TCP
(DCTCP) congestion control algorithm - we need to be able to
determine if the connection is moderated by DCTCP before the
3WHS has finished.
As we walk the available congestion control list during the
assignment, we are always guaranteed to have Reno present as
it's fixed compiled-in. Therefore, since we're doing the
early assignment, we don't have a real use for the Reno alias
tcp_init_congestion_ops anymore and can thus remove it.
Actual usage of the congestion control operations are being
made after the 3WHS has finished, in some cases however we
can access get_info() via diag if implemented, therefore we
need to zero out the private area for those modules.
Joint work with Daniel Borkmann and Glenn Judd.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
John Fastabend [Fri, 26 Sep 2014 17:02:50 +0000 (10:02 -0700)]
net: sched: cls_rcvp, complete rcu conversion
This completes the cls_rsvp conversion to RCU safe
copy, update semantics.
As a result all cases of tcf_exts_change occur on
empty lists now.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Fri, 26 Sep 2014 06:04:56 +0000 (23:04 -0700)]
dql: dql_queued() should write first to reduce bus transactions
While doing high throughput test on a BQL enabled NIC,
I found a very high cost in ndo_start_xmit() when accessing BQL data.
It turned out the problem was caused by compiler trying to be
smart, but involving a bad MESI transaction :
0.05 │ mov 0xc0(%rax),%edi // LOAD dql->num_queued
0.48 │ mov %edx,0xc8(%rax) // STORE dql->last_obj_cnt = count
58.23 │ add %edx,%edi
0.58 │ cmp %edi,0xc4(%rax)
0.76 │ mov %edi,0xc0(%rax) // STORE dql->num_queued += count
0.72 │ js bd8
I got an incredible 10 % gain [1] by making sure cpu do not attempt
to get the cache line in Shared mode, but directly requests for
ownership.
New code :
mov %edx,0xc8(%rax) // STORE dql->last_obj_cnt = count
add %edx,0xc0(%rax) // RMW dql->num_queued += count
mov 0xc4(%rax),%ecx // LOAD dql->adj_limit
mov 0xc0(%rax),%edx // LOAD dql->num_queued
cmp %edx,%ecx
The TX completion was running from another cpu, with high interrupts
rate.
Note that I am using barrier() as a soft hint, as mb() here could be
too heavy cost.
[1] This was a netperf TCP_STREAM with TSO disabled, but GSO enabled.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WANG Cong [Thu, 25 Sep 2014 19:06:05 +0000 (12:06 -0700)]
net_sched: fix another regression in cls_tcindex
Clearly the following change is not expected:
- if (!cp.perfect && !cp.h)
- cp.alloc_hash = cp.hash;
+ if (!cp->perfect && cp->h)
+ cp->alloc_hash = cp->hash;
Fixes: commit 331b72922c5f58d48fd ("net: sched: RCU cls_tcindex")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WANG Cong [Thu, 25 Sep 2014 19:06:04 +0000 (12:06 -0700)]
net_sched: fix errno in tcindex_set_parms()
When kmemdup() fails, we should return -ENOMEM.
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 28 Sep 2014 21:32:16 +0000 (17:32 -0400)]
Merge branch 'cxgb4-next'
Hariprasad Shenai says:
====================
cxgb4: Use new BAR2 GTS for T5, adds adaptive rx and few Device ID's
This patch series adds support to use new BAR2 GTS for T5 adapter.
Adds support for adaptive rx. Remove redundant variable from a macro of
cxgb4vf driver. Adds Device ID for new adapters.
The patches series is created against 'net-next' tree.
And includes patches on cxgb4 and cxgb4vf driver.
We have included all the maintainers of respective drivers. Kindly review the
change and let us know in case of any review comments.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Hariprasad Shenai [Thu, 25 Sep 2014 18:53:55 +0000 (00:23 +0530)]
cxgb4: Add support for adaptive rx
Based on original work by Kumar Sanghvi <kumaras@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hariprasad Shenai [Thu, 25 Sep 2014 18:53:54 +0000 (00:23 +0530)]
cxgb4/cxgb4vf: Add Devicde ID for two more adapter
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hariprasad Shenai [Thu, 25 Sep 2014 18:53:53 +0000 (00:23 +0530)]
cxgb4vf: Remove superfluous "idx" parameter of CH_DEVICE() macro.
Remove redundant idx parameter of CH_DEVICE() macro, its always zero.
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hariprasad Shenai [Thu, 25 Sep 2014 18:53:52 +0000 (00:23 +0530)]
cxgb4: Use BAR2 Going To Sleep (GTS) for T5 and later.
Use BAR2 GTS for T5. If we are on T4 use the old doorbell mechanism;
otherwise ue the new BAR2 mechanism. Use BAR2 doorbells for refilling FL's.
Based on original work by Casey Leedom <leedom@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rick Jones [Thu, 25 Sep 2014 17:55:28 +0000 (10:55 -0700)]
arp: Do not perturb drop profiles with ignored ARP packets
We do not wish to disturb dropwatch or perf drop profiles with an ARP
we will ignore.
Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WANG Cong [Thu, 25 Sep 2014 17:26:37 +0000 (10:26 -0700)]
net_sched: remove the first parameter from tcf_exts_destroy()
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <hadi@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Thu, 25 Sep 2014 14:17:49 +0000 (07:17 -0700)]
mlx4: exploit skb->xmit_more to conditionally send doorbell
skb->xmit_more tells us if another skb is coming next.
We need to send doorbell when : xmit_more is not set,
or txqueue is stopped (preventing next skb to come immediately)
Tested with a modified pktgen version, I got a 40% increase of
throughput.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 28 Sep 2014 21:24:32 +0000 (17:24 -0400)]
Merge branch 'r8152'
Hayes Wang says:
====================
r8152: support setting eee by ethtool
Modify some definitions about EEE, and add the support of setting
the EEE through ethtool.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
hayeswang [Thu, 25 Sep 2014 12:54:02 +0000 (20:54 +0800)]
r8152: support ethtool eee
Support get_eee() and set_eee() of ethtool_ops.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hayeswang [Thu, 25 Sep 2014 12:54:01 +0000 (20:54 +0800)]
r8152: add functions to set EEE
Add functions to enable EEE and set EEE advertisement.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hayeswang [Thu, 25 Sep 2014 12:54:00 +0000 (20:54 +0800)]
r8152: change the EEE definition
Replace the EEE definitions with the ones which is declared
in "mdio.h".
Chage some definitions to make them readable.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 28 Sep 2014 21:22:21 +0000 (17:22 -0400)]
Merge branch 'defxx-next'
Maciej W. Rozycki says:
====================
defxx: DEFEA fixes and updates
I have finally got my hands on an EISA variation of the board (DEC
FDDIcontroller/EISA aka DEFEA) and was able to do some testing. Here are
initial updates to the driver that address problems I encountered so far.
More to come later on as I get back to the system that I have in a remote
location -- I need to double-check MMIO support and see what might have
been causing spurious interrupts I saw with the 8259A PIC the board's
interrupt line has been routed to.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Maciej W. Rozycki [Thu, 25 Sep 2014 10:06:55 +0000 (11:06 +0100)]
defxx: DEFEA's ESIC port I/O decoding cleanup
Use the slot-specific I/O range for decoding accesses to PDQ ASIC
registers (IOCS0) and the discrete Burst Holdoff register (IOCS1) as per
the "HD64981F EISA Slave Interface Controller (ESIC)" datasheet. Use
disjoint decode ranges now that the assignment of chip selects is known.
Update the span of the port I/O resource requested accordingly.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Maciej W. Rozycki [Thu, 25 Sep 2014 10:06:45 +0000 (11:06 +0100)]
defxx: DEFEA's Burst Holdoff register initialization fix
Use the mask rather than bit number macro to initialize the chip select
control bit for PDQ register space decoding in the Burst Holdoff register.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Maciej W. Rozycki [Thu, 25 Sep 2014 10:06:39 +0000 (11:06 +0100)]
defxx: Correct DEFEA's ESIC port I/O accesses
Reverse the order of arguments to `outb', data to write comes first.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 28 Sep 2014 21:19:15 +0000 (17:19 -0400)]
Merge branch 'master' of git://git./linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:
====================
pull request (net-next): ipsec-next 2014-09-25
1) Remove useless hash_resize_mutex in xfrm_hash_resize().
This mutex is used only there, but xfrm_hash_resize()
can't be called concurrently at all. From Ying Xue.
2) Extend policy hashing to prefixed policies based on
prefix lenght thresholds. From Christophe Gouault.
3) Make the policy hash table thresholds configurable
via netlink. From Christophe Gouault.
4) Remove the maximum authentication length for AH.
This was needed to limit stack usage. We switched
already to allocate space, so no need to keep the
limit. From Herbert Xu.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 28 Sep 2014 21:14:15 +0000 (17:14 -0400)]
Merge branch 'dsa_eee'
Florian Fainelli says:
====================
net: dsa: EEE and other PM features
This patch set allows DSA switch drivers to enable/disable/query EEE on a
per-port level, as well as control precisely which switch ports are
enable/disabled.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli [Thu, 25 Sep 2014 00:05:22 +0000 (17:05 -0700)]
net: dsa: bcm_sf2: add support for controlling EEE
When EEE is enabled, negotiate this feature with the PHY and make sure
that the capability checking, local EEE advertisement, link partner EEE
advertisement and auto-negotiation resolution returned by phy_init_eee()
is positive, and enable EEE at the switch level.
While querying the current EEE settings, verify the low-power indication
and indicate its status.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli [Thu, 25 Sep 2014 00:05:21 +0000 (17:05 -0700)]
net: dsa: allow switches driver to implement get/set EEE
Allow switches driver to query and enable/disable EEE on a per-port
basis by implementing the ethtool_{get,set}_eee settings and delegating
these operations to the switch driver.
set_eee() will need to coordinate with the PHY driver to make sure that
EEE is enabled, the link-partner supports it and the auto-negotiation
result is satisfactory.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli [Thu, 25 Sep 2014 00:05:20 +0000 (17:05 -0700)]
net: dsa: bcm_sf2: add port_enable/disable callbacks
The SF2 switch driver is already architected around per-port
enable/disable callbacks, so we just need a slight update to our
existing bcm_sf2_port_setup() resp. bcm_sf2_port_disable() functions to
be suitable as callbacks for port_enable/port_disable.
We need to shuffle a little the code that does the per-port VLAN
configuration/isolation since ports can now be brought up/down
separately, so we need to make sure that IMP (CPU, management) port is
always included in that specific port setup.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli [Thu, 25 Sep 2014 00:05:19 +0000 (17:05 -0700)]
net: dsa: bcm_sf2: disable RGMII interface(s) when link is down
When the link is down, disable the RGMII interface to conserve as much
power as possible. We re-enable the RGMII interface whenever the link is
detected.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli [Thu, 25 Sep 2014 00:05:18 +0000 (17:05 -0700)]
net: dsa: allow enabling and disable switch ports
Whenever a per-port network device is used/unused, invoke the switch
driver port_enable/port_disable callbacks to allow saving as much power
as possible by disabling unused parts of the switch (RX/TX logic, memory
arrays, PHYs...). We supply a PHY device argument to make sure the
switch driver can act on the PHY device if needed (like putting/taking
the PHY out of deep low power mode).
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli [Thu, 25 Sep 2014 00:05:17 +0000 (17:05 -0700)]
net: dsa: start and stop the PHY state machine
dsa_slave_open() should start the PHY library state machine for its PHY
interface, and dsa_slave_close() should stop the PHY library state
machine accordingly.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Peter Pan(潘卫平) [Wed, 24 Sep 2014 14:17:02 +0000 (22:17 +0800)]
tcp: use tcp_flags in tcp_data_queue()
This patch is a cleanup which follows the idea in commit
e11ecddf5128 (tcp: use
TCP_SKB_CB(skb)->tcp_flags in input path),
and it may reduce register pressure since skb->cb[] access is fast,
bacause skb is probably in a register.
v2: remove variable th
v3: reword the changelog
Signed-off-by: Weiping Pan <panweiping3@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Wed, 24 Sep 2014 11:11:22 +0000 (04:11 -0700)]
tcp: change tcp_skb_pcount() location
Our goal is to access no more than one cache line access per skb in
a write or receive queue when doing the various walks.
After recent TCP_SKB_CB() reorganizations, it is almost done.
Last part is tcp_skb_pcount() which currently uses
skb_shinfo(skb)->gso_segs, which is a terrible choice, because it needs
3 cache lines in current kernel (skb->head, skb->end, and
shinfo->gso_segs are all in 3 different cache lines, far from skb->cb)
This very simple patch reuses space currently taken by tcp_tw_isn
only in input path, as tcp_skb_pcount is only needed for skb stored in
write queue.
This considerably speeds up tcp_ack(), granted we avoid shinfo->tx_flags
to get SKBTX_ACK_TSTAMP, which seems possible.
This also speeds up all sack processing in general.
This speeds up tcp_sendmsg() because it no longer has to access/dirty
shinfo.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 28 Sep 2014 20:35:49 +0000 (16:35 -0400)]
Merge branch 'tcp_skb_cb'
Eric Dumazet says:
====================
tcp: better TCP_SKB_CB layout
TCP had the assumption that IPCB and IP6CB are first members of skb->cb[]
This is fine, except that IPCB/IP6CB are used in TCP for a very short time
in input path.
What really matters for TCP stack is to get skb->next,
TCP_SKB_CB(skb)->seq, and TCP_SKB_CB(skb)->end_seq in the same cache line.
skb that are immediately consumed do not care because whole skb->cb[] is
hot in cpu cache, while skb that sit in wocket write queue or receive queues
do not need TCP_SKB_CB(skb)->header at all.
This patch set implements the prereq for IPv4, IPv6, and TCP to make this
possible. This makes TCP more efficient.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Sat, 27 Sep 2014 16:50:57 +0000 (09:50 -0700)]
tcp: better TCP_SKB_CB layout to reduce cache line misses
TCP maintains lists of skb in write queue, and in receive queues
(in order and out of order queues)
Scanning these lists both in input and output path usually requires
access to skb->next, TCP_SKB_CB(skb)->seq, and TCP_SKB_CB(skb)->end_seq
These fields are currently in two different cache lines, meaning we
waste lot of memory bandwidth when these queues are big and flows
have either packet drops or packet reorders.
We can move TCP_SKB_CB(skb)->header at the end of TCP_SKB_CB, because
this header is not used in fast path. This allows TCP to search much faster
in the skb lists.
Even with regular flows, we save one cache line miss in fast path.
Thanks to Christoph Paasch for noticing we need to cleanup
skb->cb[] (IPCB/IP6CB) before entering IP stack in tx path,
and that I forgot IPCB use in tcp_v4_hnd_req() and tcp_v4_save_options().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Sat, 27 Sep 2014 16:50:56 +0000 (09:50 -0700)]
ipv6: add a struct inet6_skb_parm param to ipv6_opt_accepted()
ipv6_opt_accepted() assumes IP6CB(skb) holds the struct inet6_skb_parm
that it needs. Lets not assume this, as TCP stack might use a different
place.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Sat, 27 Sep 2014 16:50:55 +0000 (09:50 -0700)]
ipv4: rename ip_options_echo to __ip_options_echo()
ip_options_echo() assumes struct ip_options is provided in &IPCB(skb)->opt
Lets break this assumption, but provide a helper to not change all call points.
ip_send_unicast_reply() gets a new struct ip_options pointer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Wed, 24 Sep 2014 01:39:30 +0000 (18:39 -0700)]
net : optimize skb_release_data()
Cache skb_shinfo(skb) in a variable to avoid computing it multiple
times.
Reorganize the tests to remove one indentation level.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Tue, 23 Sep 2014 21:36:11 +0000 (14:36 -0700)]
sparc: bpf_jit: add support for BPF_LD(X) | BPF_LEN instructions
BPF_LD | BPF_W | BPF_LEN instruction is occasionally used by tcpdump
and present in 11 tests in lib/test_bpf.c
Teach sparc JIT compiler to emit it.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tobias Klauser [Tue, 23 Sep 2014 13:19:41 +0000 (15:19 +0200)]
net: bcmgenet: Fix compile warning
bcmgenet_wol_resume() is only used in bcmgenet_resume(), which is only
defined when CONFIG_PM_SLEEP is enabled. This leads to the following
compile warning when building with !CONFIG_PM_SLEEP:
drivers/net/ethernet/broadcom/genet/bcmgenet.c:1967:12: warning: ‘bcmgenet_wol_resume’ defined but not used [-Wunused-function]
Since bcmgenet_resume() is the only user of bcmgenet_wol_resume(), fix
this by directly inlining the function there.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wang Sheng-Hui [Tue, 23 Sep 2014 12:02:15 +0000 (20:02 +0800)]
net/openvswitch: remove dup comment in vport.h
Remove the duplicated comment
"/* The following definitions are for users of the vport subsytem: */"
in vport.h
Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 26 Sep 2014 20:23:12 +0000 (16:23 -0400)]
Merge branch 'master' of git://git./linux/kernel/git/jkirsher/net-next
Jeff Kirsher says:
====================
Intel Wired LAN Driver Updates 2014-09-23
This patch series adds support for the FM10000 Ethernet switch host
interface. The Intel FM10000 Ethernet Switch is a 48-port Ethernet switch
supporting both Ethernet ports and PCI Express host interfaces. The fm10k
driver provides support for the host interface portion of the switch, both
PF and VF.
As the host interfaces are directly connected to the switch this results in
some significant differences versus a standard network driver. For example
there is no PHY or MII on the device. Since packets are delivered directly
from the switch to the host interface these are unnecessary. Otherwise most
of the functionality is very similar to our other network drivers such as
ixgbe or igb. For example we support all the standard network offloads,
jumbo frames, SR-IOV (64 VFS), PTP, and some VXLAN and NVGRE offloads.
v2: converted dev_consume_skb_any() to dev_kfree_skb_any()
fix up PTP code based on feedback from the community
v3: converted the use of smb_mb__before_clear_bit() to smb_mb__before_atomic()
added vmalloc header to patch 15
added prefetch header to patch 16
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
LEROY Christophe [Tue, 23 Sep 2014 08:54:37 +0000 (10:54 +0200)]
net: optimise inet_proto_csum_replace4()
csum_partial() is a generic function which is not optimised for small fixed
length calculations, and its use requires to store "from" and "to" values in
memory while we already have them available in registers. This also has impact,
especially on RISC processors. In the same spirit as the change done by
Eric Dumazet on csum_replace2(), this patch rewrites inet_proto_csum_replace4()
taking into account RFC1624.
I spotted during a NATted tcp transfert that csum_partial() is one of top 5
consuming functions (around 8%), and the second user of csum_partial() is
inet_proto_csum_replace4().
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
LEROY Christophe [Tue, 23 Sep 2014 08:54:32 +0000 (10:54 +0200)]
net: optimise csum_replace4()
csum_partial() is a generic function which is not optimised for small fixed
length calculations, and its use requires to store "from" and "to" values in
memory while we already have them available in registers. This also has impact,
especially on RISC processors. In the same spirit as the change done by
Eric Dumazet on csum_replace2(), this patch rewrites inet_proto_csum_replace4()
taking into account RFC1624.
I spotted during a NATted tcp transfert that csum_partial() is one of top 5
consuming functions (around 8%), and the second user of csum_partial() is
inet_proto_csum_replace4().
I have proposed the same modification to inet_proto_csum_replace4() in another
patch.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 26 Sep 2014 20:05:25 +0000 (16:05 -0400)]
Merge branch 'fec'
Fugang Duan says:
====================
net: fec: Code cleanup
This patches does several things:
- Fixing multiqueue issue.
- Removing the unnecessary errata workaround.
- Aligning the data buffer dma map/unmap size.
- Freeing resource after probe failed.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Nimrod Andy [Tue, 23 Sep 2014 07:40:58 +0000 (15:40 +0800)]
net: fec: free resource after phy probe failed
Free memory and disable all related clocks when there has no phy
connection or phy probe failed.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Nimrod Andy [Tue, 23 Sep 2014 07:40:57 +0000 (15:40 +0800)]
net: fec: align rx data buffer size for dma map/unmap
Align allocated rx data buffer size for dma map/unmap, otherwise
kernel print warning when enable DMA_API_DEBUG.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Nimrod Andy [Tue, 23 Sep 2014 07:40:56 +0000 (15:40 +0800)]
net: fec: remove the ERR006358 workaround for imx6sx enet
Remove the ERR006358 workaround for imx6sx enet since the hw issue
was fixed on the SOC.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Nimrod Andy [Tue, 23 Sep 2014 07:40:55 +0000 (15:40 +0800)]
net: fec: Add Ftype to BD to distiguish three tx queues for AVB
The current driver loss Ftype field init for BD, which cause tx
queue #1 and #2 cannot work well.
Add Ftype field to BD to distiguish three queues for AVB:
0 -> Best Effort
1 -> ClassA
2 -> ClassB
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Mon, 22 Sep 2014 23:29:32 +0000 (16:29 -0700)]
net: introduce __skb_header_release()
While profiling TCP stack, I noticed one useless atomic operation
in tcp_sendmsg(), caused by skb_header_release().
It turns out all current skb_header_release() users have a fresh skb,
that no other user can see, so we can avoid one atomic operation.
Introduce __skb_header_release() to clearly document this.
This gave me a 1.5 % improvement on TCP_RR workload.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fabio Estevam [Mon, 22 Sep 2014 20:55:29 +0000 (17:55 -0300)]
fec: Remove fec_enet_select_queue()
Sparse complains about fec_enet_select_queue() not being static.
Feedback from David Miller [1] was to remove this function instead of making it
static:
"Please just delete this function.
It's overriding code which does exactly the same thing.
Actually, more precisely, this code is duplicating code in a way that
bypasses many core facilitites of the networking. For example, this
override means that socket based flow steering, XPS, etc. are all
not happening on these devices.
Without ->ndo_select_queue(), the flow dissector does __netdev_pick_tx
which is exactly what you want to happen."
[1] http://www.spinics.net/lists/netdev/msg297653.html
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 26 Sep 2014 19:19:05 +0000 (15:19 -0400)]
Merge tag 'master-2014-09-16' of git://git./linux/kernel/git/linville/wireless-next
John W. Linville says:
====================
pull request: wireless-next 2014-09-22
Please pull this batch of updates intended for the 3.18 stream...
For the mac80211 bits, Johannes says:
"This time, I have some rate minstrel improvements, support for a very
small feature from CCX that Steinar reverse-engineered, dynamic ACK
timeout support, a number of changes for TDLS, early support for radio
resource measurement and many fixes. Also, I'm changing a number of
places to clear key memory when it's freed and Intel claims copyright
for code they developed."
For the bluetooth bits, Johan says:
"Here are some more patches intended for 3.18. Most of them are cleanups
or fixes for SMP. The only exception is a fix for BR/EDR L2CAP fixed
channels which should now work better together with the L2CAP
information request procedure."
For the iwlwifi bits, Emmanuel says:
"I fix here dvm which was broken by my last pull request. Arik
continues to work on TDLS and Luca solved a few issues in CT-Kill. Eyal
keeps digging into rate scaling code, more to come soon. Besides this,
nothing really special here."
Beyond that, there are the usual big batches of updates to ath9k, b43,
mwifiex, and wil6210 as well as a handful of other bits here and there.
Also, rtlwifi gets some btcoexist attention from Larry.
Please let me know if there are problems!
====================
Had to adjust the wil6210 code to comply with Joe Perches's recent
change in net-next to make the netdev_*() routines return void instead
of 'int'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Joe Perches [Mon, 22 Sep 2014 18:10:50 +0000 (11:10 -0700)]
net: Change netdev_<level> logging functions to return void
No caller or macro uses the return value so make all
the functions return void.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Joe Perches [Mon, 22 Sep 2014 17:40:22 +0000 (10:40 -0700)]
mellanox: Change en_print to return void
No caller or macro uses the return value so make it void.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-By: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 26 Sep 2014 19:05:40 +0000 (15:05 -0400)]
Merge branch 'bpf-next'
Alexei Starovoitov says:
====================
eBPF syscall, verifier, testsuite
v14 -> v15:
- got rid of macros with hidden control flow (suggested by David)
replaced macro with explicit goto or return and simplified
where possible (affected patches #9 and #10)
- rebased, retested
v13 -> v14:
- small change to 1st patch to ease 'new userspace with old kernel'
problem (done similar to perf_copy_attr()) (suggested by Daniel)
- the rest unchanged
v12 -> v13:
- replaced 'foo __user *' pointers with __aligned_u64 (suggested by David)
- added __attribute__((aligned(8)) to 'union bpf_attr' to keep
constant alignment between patches
- updated manpage and syscall wrappers due to __aligned_u64
- rebased, retested on x64 with 32-bit and 64-bit userspace and on i386,
build tested on arm32,sparc64
v11 -> v12:
- dropped patch 11 and copied few macros to libbpf.h (suggested by Daniel)
- replaced 'enum bpf_prog_type' with u32 to be safe in compat (.. Andy)
- implemented and tested compat support (not part of this set) (.. Daniel)
- changed 'void *log_buf' to 'char *' (.. Daniel)
- combined struct bpf_work_struct and bpf_prog_info (.. Daniel)
- added better return value explanation to manpage (.. Andy)
- added log_buf/log_size explanation to manpage (.. Andy & Daniel)
- added a lot more info about prog_type and map_type to manpage (.. Andy)
- rebased, tweaked test_stubs
Patches 1-4 establish BPF syscall shell for maps and programs.
Patches 5-10 add verifier step by step
Patch 11 adds test stubs for 'unspec' program type and verifier testsuite
from user space
Note that patches 1,3,4,7 add commands and attributes to the syscall
while being backwards compatible from each other, which should demonstrate
how other commands can be added in the future.
After this set the programs can be loaded for testing only. They cannot
be attached to any events. Though manpage talks about tracing and sockets,
it will be a subject of future patches.
Please take a look at manpage:
BPF(2) Linux Programmer's Manual BPF(2)
NAME
bpf - perform a command on eBPF map or program
SYNOPSIS
#include <linux/bpf.h>
int bpf(int cmd, union bpf_attr *attr, unsigned int size);
DESCRIPTION
bpf() syscall is a multiplexor for a range of different operations on
eBPF which can be characterized as "universal in-kernel virtual
machine". eBPF is similar to original Berkeley Packet Filter (or
"classic BPF") used to filter network packets. Both statically analyze
the programs before loading them into the kernel to ensure that
programs cannot harm the running system.
eBPF extends classic BPF in multiple ways including ability to call in-
kernel helper functions and access shared data structures like eBPF
maps. The programs can be written in a restricted C that is compiled
into eBPF bytecode and executed on the eBPF virtual machine or JITed
into native instruction set.
eBPF Design/Architecture
eBPF maps is a generic storage of different types. User process can
create multiple maps (with key/value being opaque bytes of data) and
access them via file descriptor. In parallel eBPF programs can access
maps from inside the kernel. It's up to user process and eBPF program
to decide what they store inside maps.
eBPF programs are similar to kernel modules. They are loaded by the
user process and automatically unloaded when process exits. Each eBPF
program is a safe run-to-completion set of instructions. eBPF verifier
statically determines that the program terminates and is safe to
execute. During verification the program takes a hold of maps that it
intends to use, so selected maps cannot be removed until the program is
unloaded. The program can be attached to different events. These events
can be packets, tracepoint events and other types in the future. A new
event triggers execution of the program which may store information
about the event in the maps. Beyond storing data the programs may call
into in-kernel helper functions which may, for example, dump stack, do
trace_printk or other forms of live kernel debugging. The same program
can be attached to multiple events. Different programs can access the
same map:
tracepoint tracepoint tracepoint sk_buff sk_buff
event A event B event C on eth0 on eth1
| | | | |
| | | | |
--> tracing <-- tracing socket socket
prog_1 prog_2 prog_3 prog_4
| | | |
|--- -----| |-------| map_3
map_1 map_2
Syscall Arguments
bpf() syscall operation is determined by cmd which can be one of the
following:
BPF_MAP_CREATE
Create a map with given type and attributes and return map FD
BPF_MAP_LOOKUP_ELEM
Lookup element by key in a given map and return its value
BPF_MAP_UPDATE_ELEM
Create or update element (key/value pair) in a given map
BPF_MAP_DELETE_ELEM
Lookup and delete element by key in a given map
BPF_MAP_GET_NEXT_KEY
Lookup element by key in a given map and return key of next
element
BPF_PROG_LOAD
Verify and load eBPF program
attr is a pointer to a union of type bpf_attr as defined below.
size is the size of the union.
union bpf_attr {
struct { /* anonymous struct used by BPF_MAP_CREATE command */
__u32 map_type;
__u32 key_size; /* size of key in bytes */
__u32 value_size; /* size of value in bytes */
__u32 max_entries; /* max number of entries in a map */
};
struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
__u32 map_fd;
__aligned_u64 key;
union {
__aligned_u64 value;
__aligned_u64 next_key;
};
};
struct { /* anonymous struct used by BPF_PROG_LOAD command */
__u32 prog_type;
__u32 insn_cnt;
__aligned_u64 insns; /* 'const struct bpf_insn *' */
__aligned_u64 license; /* 'const char *' */
__u32 log_level; /* verbosity level of eBPF verifier */
__u32 log_size; /* size of user buffer */
__aligned_u64 log_buf; /* user supplied 'char *' buffer */
};
} __attribute__((aligned(8)));
eBPF maps
maps is a generic storage of different types for sharing data between
kernel and userspace.
Any map type has the following attributes:
. type
. max number of elements
. key size in bytes
. value size in bytes
The following wrapper functions demonstrate how this syscall can be
used to access the maps. The functions use the cmd argument to invoke
different operations.
BPF_MAP_CREATE
int bpf_create_map(enum bpf_map_type map_type, int key_size,
int value_size, int max_entries)
{
union bpf_attr attr = {
.map_type = map_type,
.key_size = key_size,
.value_size = value_size,
.max_entries = max_entries
};
return bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
}
bpf() syscall creates a map of map_type type and given
attributes key_size, value_size, max_entries. On success it
returns process-local file descriptor. On error, -1 is returned
and errno is set to EINVAL or EPERM or ENOMEM.
The attributes key_size and value_size will be used by verifier
during program loading to check that program is calling
bpf_map_*_elem() helper functions with correctly initialized key
and that program doesn't access map element value beyond
specified value_size. For example, when map is created with
key_size = 8 and program does:
bpf_map_lookup_elem(map_fd, fp - 4)
such program will be rejected, since in-kernel helper function
bpf_map_lookup_elem(map_fd, void *key) expects to read 8 bytes
from 'key' pointer, but 'fp - 4' starting address will cause out
of bounds stack access.
Similarly, when map is created with value_size = 1 and program
does:
value = bpf_map_lookup_elem(...);
*(u32 *)value = 1;
such program will be rejected, since it accesses value pointer
beyond specified 1 byte value_size limit.
Currently only hash table map_type is supported:
enum bpf_map_type {
BPF_MAP_TYPE_UNSPEC,
BPF_MAP_TYPE_HASH,
};
map_type selects one of the available map implementations in
kernel. For all map_types eBPF programs access maps with the
same bpf_map_lookup_elem()/bpf_map_update_elem() helper
functions.
BPF_MAP_LOOKUP_ELEM
int bpf_lookup_elem(int fd, void *key, void *value)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
};
return bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
}
bpf() syscall looks up an element with given key in a map fd.
If element is found it returns zero and stores element's value
into value. If element is not found it returns -1 and sets
errno to ENOENT.
BPF_MAP_UPDATE_ELEM
int bpf_update_elem(int fd, void *key, void *value)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
};
return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
}
The call creates or updates element with given key/value in a
map fd. On success it returns zero. On error, -1 is returned
and errno is set to EINVAL or EPERM or ENOMEM or E2BIG. E2BIG
indicates that number of elements in the map reached max_entries
limit specified at map creation time.
BPF_MAP_DELETE_ELEM
int bpf_delete_elem(int fd, void *key)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
};
return bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
}
The call deletes an element in a map fd with given key. Returns
zero on success. If element is not found it returns -1 and sets
errno to ENOENT.
BPF_MAP_GET_NEXT_KEY
int bpf_get_next_key(int fd, void *key, void *next_key)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.next_key = ptr_to_u64(next_key),
};
return bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
}
The call looks up an element by key in a given map fd and
returns key of the next element into next_key pointer. If key is
not found, it return zero and returns key of the first element
into next_key. If key is the last element, it returns -1 and
sets errno to ENOENT. Other possible errno values are ENOMEM,
EFAULT, EPERM, EINVAL. This method can be used to iterate over
all elements of the map.
close(map_fd)
will delete the map map_fd. Exiting process will delete all
maps automatically.
eBPF programs
BPF_PROG_LOAD
This cmd is used to load eBPF program into the kernel.
char bpf_log_buf[LOG_BUF_SIZE];
int bpf_prog_load(enum bpf_prog_type prog_type,
const struct bpf_insn *insns, int insn_cnt,
const char *license)
{
union bpf_attr attr = {
.prog_type = prog_type,
.insns = ptr_to_u64(insns),
.insn_cnt = insn_cnt,
.license = ptr_to_u64(license),
.log_buf = ptr_to_u64(bpf_log_buf),
.log_size = LOG_BUF_SIZE,
.log_level = 1,
};
return bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
}
prog_type is one of the available program types:
enum bpf_prog_type {
BPF_PROG_TYPE_UNSPEC,
BPF_PROG_TYPE_SOCKET,
BPF_PROG_TYPE_TRACING,
};
By picking prog_type program author selects a set of helper
functions callable from eBPF program and corresponding format of
struct bpf_context (which is the data blob passed into the
program as the first argument). For example, the programs
loaded with prog_type = TYPE_TRACING may call bpf_printk()
helper, whereas TYPE_SOCKET programs may not. The set of
functions available to the programs under given type may
increase in the future.
Currently the set of functions for TYPE_TRACING is:
bpf_map_lookup_elem(map_fd, void *key) // lookup key in a map_fd
bpf_map_update_elem(map_fd, void *key, void *value) // update key/value
bpf_map_delete_elem(map_fd, void *key) // delete key in a map_fd
bpf_ktime_get_ns(void) // returns current ktime
bpf_printk(char *fmt, int fmt_size, ...) // prints into trace buffer
bpf_memcmp(void *ptr1, void *ptr2, int size) // non-faulting memcmp
bpf_fetch_ptr(void *ptr) // non-faulting load pointer from any address
bpf_fetch_u8(void *ptr) // non-faulting 1 byte load
bpf_fetch_u16(void *ptr) // other non-faulting loads
bpf_fetch_u32(void *ptr)
bpf_fetch_u64(void *ptr)
and bpf_context is defined as:
struct bpf_context {
/* argN fields match one to one to arguments passed to trace events */
u64 arg1, arg2, arg3, arg4, arg5, arg6;
/* return value from kretprobe event or from syscall_exit event */
u64 ret;
};
The set of helper functions for TYPE_SOCKET is TBD.
More program types may be added in the future. Like
BPF_PROG_TYPE_USER_TRACING for unprivileged programs.
BPF_PROG_TYPE_UNSPEC is used for testing only. Such programs
cannot be attached to events.
insns array of "struct bpf_insn" instructions
insn_cnt number of instructions in the program
license license string, which must be GPL compatible to call
helper functions marked gpl_only
log_buf user supplied buffer that in-kernel verifier is using to
store verification log. Log is a multi-line string that should
be used by program author to understand how verifier came to
conclusion that program is unsafe. The format of the output can
change at any time as verifier evolves.
log_size size of user buffer. If size of the buffer is not large
enough to store all verifier messages, -1 is returned and errno
is set to ENOSPC.
log_level verbosity level of eBPF verifier, where zero means no
logs provided
close(prog_fd)
will unload eBPF program
The maps are accesible from programs and generally tie the two
together. Programs process various events (like tracepoint, kprobe,
packets) and store the data into maps. User space fetches data from
maps. Either the same or a different map may be used by user space as
configuration space to alter program behavior on the fly.
Events
Once an eBPF program is loaded, it can be attached to an event. Various
kernel subsystems have different ways to do so. For example:
setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd, sizeof(prog_fd));
will attach the program prog_fd to socket sock which was received by
prior call to socket().
ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
will attach the program prog_fd to perf event event_fd which was
received by prior call to perf_event_open().
Another way to attach the program to a tracing event is:
event_fd = open("/sys/kernel/debug/tracing/events/skb/kfree_skb/filter");
write(event_fd, "bpf-123"); /* where 123 is eBPF program FD */
/* here program is attached and will be triggered by events */
close(event_fd); /* to detach from event */
EXAMPLES
/* eBPF+sockets example:
* 1. create map with maximum of 2 elements
* 2. set map[6] = 0 and map[17] = 0
* 3. load eBPF program that counts number of TCP and UDP packets received
* via map[skb->ip->proto]++
* 4. attach prog_fd to raw socket via setsockopt()
* 5. print number of received TCP/UDP packets every second
*/
int main(int ac, char **av)
{
int sock, map_fd, prog_fd, key;
long long value = 0, tcp_cnt, udp_cnt;
map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 2);
if (map_fd < 0) {
printf("failed to create map '%s'\n", strerror(errno));
/* likely not run as root */
return 1;
}
key = 6; /* ip->proto == tcp */
assert(bpf_update_elem(map_fd, &key, &value) == 0);
key = 17; /* ip->proto == udp */
assert(bpf_update_elem(map_fd, &key, &value) == 0);
struct bpf_insn prog[] = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), /* r6 = r1 */
BPF_LD_ABS(BPF_B, 14 + 9), /* r0 = ip->proto */
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4),/* *(u32 *)(fp - 4) = r0 */
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), /* r2 = fp */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), /* r2 = r2 - 4 */
BPF_LD_MAP_FD(BPF_REG_1, map_fd), /* r1 = map_fd */
BPF_CALL_FUNC(BPF_FUNC_map_lookup_elem), /* r0 = map_lookup(r1, r2) */
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2), /* if (r0 == 0) goto pc+2 */
BPF_MOV64_IMM(BPF_REG_1, 1), /* r1 = 1 */
BPF_XADD(BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* lock *(u64 *)r0 += r1 */
BPF_MOV64_IMM(BPF_REG_0, 0), /* r0 = 0 */
BPF_EXIT_INSN(), /* return r0 */
};
prog_fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET, prog, sizeof(prog), "GPL");
assert(prog_fd >= 0);
sock = open_raw_sock("lo");
assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd,
sizeof(prog_fd)) == 0);
for (;;) {
key = 6;
assert(bpf_lookup_elem(map_fd, &key, &tcp_cnt) == 0);
key = 17;
assert(bpf_lookup_elem(map_fd, &key, &udp_cnt) == 0);
printf("TCP %lld UDP %lld packets0, tcp_cnt, udp_cnt);
sleep(1);
}
return 0;
}
RETURN VALUE
For a successful call, the return value depends on the operation:
BPF_MAP_CREATE
The new file descriptor associated with eBPF map.
BPF_PROG_LOAD
The new file descriptor associated with eBPF program.
All other commands
Zero.
On error, -1 is returned, and errno is set appropriately.
ERRORS
EPERM bpf() syscall was made without sufficient privilege (without the
CAP_SYS_ADMIN capability).
ENOMEM Cannot allocate sufficient memory.
EBADF fd is not an open file descriptor
EFAULT One of the pointers ( key or value or log_buf or insns ) is
outside accessible address space.
EINVAL The value specified in cmd is not recognized by this kernel.
EINVAL For BPF_MAP_CREATE, either map_type or attributes are invalid.
EINVAL For BPF_MAP_*_ELEM commands, some of the fields of "union
bpf_attr" unused by this command are not set to zero.
EINVAL For BPF_PROG_LOAD, attempt to load invalid program (unrecognized
instruction or uses reserved fields or jumps out of range or
loop detected or calls unknown function).
EACCES For BPF_PROG_LOAD, though program has valid instructions, it was
rejected, since it was deemed unsafe (may access disallowed
memory region or uninitialized stack/register or function
constraints don't match actual types or misaligned access). In
such case it is recommended to call bpf() again with log_level =
1 and examine log_buf for specific reason provided by verifier.
ENOENT For BPF_MAP_LOOKUP_ELEM or BPF_MAP_DELETE_ELEM, indicates that
element with given key was not found.
E2BIG program is too large or a map reached max_entries limit (max
number of elements).
NOTES
These commands may be used only by a privileged process (one having the
CAP_SYS_ADMIN capability).
SEE ALSO
eBPF architecture and instruction set is explained in
Documentation/networking/filter.txt
Linux 2014-09-16 BPF(2)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:07 +0000 (00:17 -0700)]
bpf: mini eBPF library, test stubs and verifier testsuite
1.
the library includes a trivial set of BPF syscall wrappers:
int bpf_create_map(int key_size, int value_size, int max_entries);
int bpf_update_elem(int fd, void *key, void *value);
int bpf_lookup_elem(int fd, void *key, void *value);
int bpf_delete_elem(int fd, void *key);
int bpf_get_next_key(int fd, void *key, void *next_key);
int bpf_prog_load(enum bpf_prog_type prog_type,
const struct sock_filter_int *insns, int insn_len,
const char *license);
bpf_prog_load() stores verifier log into global bpf_log_buf[] array
and BPF_*() macros to build instructions
2.
test stubs configure eBPF infra with 'unspec' map and program types.
These are fake types used by user space testsuite only.
3.
verifier tests valid and invalid programs and expects predefined
error log messages from kernel.
40 tests so far.
$ sudo ./test_verifier
#0 add+sub+mul OK
#1 unreachable OK
#2 unreachable2 OK
#3 out of range jump OK
#4 out of range jump2 OK
#5 test1 ld_imm64 OK
...
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:06 +0000 (00:17 -0700)]
bpf: verifier (add verifier core)
This patch adds verifier core which simulates execution of every insn and
records the state of registers and program stack. Every branch instruction seen
during simulation is pushed into state stack. When verifier reaches BPF_EXIT,
it pops the state from the stack and continues until it reaches BPF_EXIT again.
For program:
1: bpf_mov r1, xxx
2: if (r1 == 0) goto 5
3: bpf_mov r0, 1
4: goto 6
5: bpf_mov r0, 2
6: bpf_exit
The verifier will walk insns: 1, 2, 3, 4, 6
then it will pop the state recorded at insn#2 and will continue: 5, 6
This way it walks all possible paths through the program and checks all
possible values of registers. While doing so, it checks for:
- invalid instructions
- uninitialized register access
- uninitialized stack access
- misaligned stack access
- out of range stack access
- invalid calling convention
- instruction encoding is not using reserved fields
Kernel subsystem configures the verifier with two callbacks:
- bool (*is_valid_access)(int off, int size, enum bpf_access_type type);
that provides information to the verifer which fields of 'ctx'
are accessible (remember 'ctx' is the first argument to eBPF program)
- const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id);
returns argument constraints of kernel helper functions that eBPF program
may call, so that verifier can checks that R1-R5 types match the prototype
More details in Documentation/networking/filter.txt and in kernel/bpf/verifier.c
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:05 +0000 (00:17 -0700)]
bpf: verifier (add branch/goto checks)
check that control flow graph of eBPF program is a directed acyclic graph
check_cfg() does:
- detect loops
- detect unreachable instructions
- check that program terminates with BPF_EXIT insn
- check that all branches are within program boundary
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:04 +0000 (00:17 -0700)]
bpf: handle pseudo BPF_LD_IMM64 insn
eBPF programs passed from userspace are using pseudo BPF_LD_IMM64 instructions
to refer to process-local map_fd. Scan the program for such instructions and
if FDs are valid, convert them to 'struct bpf_map' pointers which will be used
by verifier to check access to maps in bpf_map_lookup/update() calls.
If program passes verifier, convert pseudo BPF_LD_IMM64 into generic by dropping
BPF_PSEUDO_MAP_FD flag.
Note that eBPF interpreter is generic and knows nothing about pseudo insns.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:03 +0000 (00:17 -0700)]
bpf: verifier (add ability to receive verification log)
add optional attributes for BPF_PROG_LOAD syscall:
union bpf_attr {
struct {
...
__u32 log_level; /* verbosity level of eBPF verifier */
__u32 log_size; /* size of user buffer */
__aligned_u64 log_buf; /* user supplied 'char *buffer' */
};
};
when log_level > 0 the verifier will return its verification log in the user
supplied buffer 'log_buf' which can be used by program author to analyze why
verifier rejected given program.
'Understanding eBPF verifier messages' section of Documentation/networking/filter.txt
provides several examples of these messages, like the program:
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_CALL_FUNC(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 4, 0),
BPF_EXIT_INSN(),
will be rejected with the following multi-line message in log_buf:
0: (7a) *(u64 *)(r10 -8) = 0
1: (bf) r2 = r10
2: (07) r2 += -8
3: (b7) r1 = 0
4: (85) call 1
5: (15) if r0 == 0x0 goto pc+1
R0=map_ptr R10=fp
6: (7a) *(u64 *)(r0 +4) = 0
misaligned access off 4 size 8
The format of the output can change at any time as verifier evolves.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:02 +0000 (00:17 -0700)]
bpf: verifier (add docs)
this patch adds all of eBPF verfier documentation and empty bpf_check()
The end goal for the verifier is to statically check safety of the program.
Verifier will catch:
- loops
- out of range jumps
- unreachable instructions
- invalid instructions
- uninitialized register access
- uninitialized stack access
- misaligned stack access
- out of range stack access
- invalid calling convention
More details in Documentation/networking/filter.txt
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:01 +0000 (00:17 -0700)]
bpf: handle pseudo BPF_CALL insn
in native eBPF programs userspace is using pseudo BPF_CALL instructions
which encode one of 'enum bpf_func_id' inside insn->imm field.
Verifier checks that program using correct function arguments to given func_id.
If all checks passed, kernel needs to fixup BPF_CALL->imm fields by
replacing func_id with in-kernel function pointer.
eBPF interpreter just calls the function.
In-kernel eBPF users continue to use generic BPF_CALL.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:17:00 +0000 (00:17 -0700)]
bpf: expand BPF syscall with program load/unload
eBPF programs are similar to kernel modules. They are loaded by the user
process and automatically unloaded when process exits. Each eBPF program is
a safe run-to-completion set of instructions. eBPF verifier statically
determines that the program terminates and is safe to execute.
The following syscall wrapper can be used to load the program:
int bpf_prog_load(enum bpf_prog_type prog_type,
const struct bpf_insn *insns, int insn_cnt,
const char *license)
{
union bpf_attr attr = {
.prog_type = prog_type,
.insns = ptr_to_u64(insns),
.insn_cnt = insn_cnt,
.license = ptr_to_u64(license),
};
return bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
}
where 'insns' is an array of eBPF instructions and 'license' is a string
that must be GPL compatible to call helper functions marked gpl_only
Upon succesful load the syscall returns prog_fd.
Use close(prog_fd) to unload the program.
User space tests and examples follow in the later patches
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:16:59 +0000 (00:16 -0700)]
bpf: add lookup/update/delete/iterate methods to BPF maps
'maps' is a generic storage of different types for sharing data between kernel
and userspace.
The maps are accessed from user space via BPF syscall, which has commands:
- create a map with given type and attributes
fd = bpf(BPF_MAP_CREATE, union bpf_attr *attr, u32 size)
returns fd or negative error
- lookup key in a given map referenced by fd
err = bpf(BPF_MAP_LOOKUP_ELEM, union bpf_attr *attr, u32 size)
using attr->map_fd, attr->key, attr->value
returns zero and stores found elem into value or negative error
- create or update key/value pair in a given map
err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size)
using attr->map_fd, attr->key, attr->value
returns zero or negative error
- find and delete element by key in a given map
err = bpf(BPF_MAP_DELETE_ELEM, union bpf_attr *attr, u32 size)
using attr->map_fd, attr->key
- iterate map elements (based on input key return next_key)
err = bpf(BPF_MAP_GET_NEXT_KEY, union bpf_attr *attr, u32 size)
using attr->map_fd, attr->key, attr->next_key
- close(fd) deletes the map
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:16:58 +0000 (00:16 -0700)]
bpf: enable bpf syscall on x64 and i386
done as separate commit to ease conflict resolution
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov [Fri, 26 Sep 2014 07:16:57 +0000 (00:16 -0700)]
bpf: introduce BPF syscall and maps
BPF syscall is a multiplexor for a range of different operations on eBPF.
This patch introduces syscall with single command to create a map.
Next patch adds commands to access maps.
'maps' is a generic storage of different types for sharing data between kernel
and userspace.
Userspace example:
/* this syscall wrapper creates a map with given type and attributes
* and returns map_fd on success.
* use close(map_fd) to delete the map
*/
int bpf_create_map(enum bpf_map_type map_type, int key_size,
int value_size, int max_entries)
{
union bpf_attr attr = {
.map_type = map_type,
.key_size = key_size,
.value_size = value_size,
.max_entries = max_entries
};
return bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
}
'union bpf_attr' is backwards compatible with future extensions.
More details in Documentation/networking/filter.txt and in manpage
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Sun, 21 Sep 2014 01:01:30 +0000 (18:01 -0700)]
net: sched: use pinned timers
While using a MQ + NETEM setup, I had confirmation that the default
timer migration ( /proc/sys/kernel/timer_migration ) is killing us.
Installing this on a receiver side of a TCP_STREAM test, (NIC has 8 TX
queues) :
EST="est 1sec 4sec"
for ETH in eth1
do
tc qd del dev $ETH root 2>/dev/null
tc qd add dev $ETH root handle 1: mq
tc qd add dev $ETH parent 1:1 $EST netem limit 70000 delay 6ms
tc qd add dev $ETH parent 1:2 $EST netem limit 70000 delay 8ms
tc qd add dev $ETH parent 1:3 $EST netem limit 70000 delay 10ms
tc qd add dev $ETH parent 1:4 $EST netem limit 70000 delay 12ms
tc qd add dev $ETH parent 1:5 $EST netem limit 70000 delay 14ms
tc qd add dev $ETH parent 1:6 $EST netem limit 70000 delay 16ms
tc qd add dev $ETH parent 1:7 $EST netem limit 80000 delay 18ms
tc qd add dev $ETH parent 1:8 $EST netem limit 90000 delay 20ms
done
We can see that timers get migrated into a single cpu, presumably idle
at the time timers are set up.
Then all qdisc dequeues run from this cpu and huge lock contention
happens. This single cpu is stuck in softirq mode and cannot dequeue
fast enough.
39.24% [kernel] [k] _raw_spin_lock
2.65% [kernel] [k] netem_enqueue
1.80% [kernel] [k] netem_dequeue
1.63% [kernel] [k] copy_user_enhanced_fast_string
1.45% [kernel] [k] _raw_spin_lock_bh
By pinning qdisc timers on the cpu running the qdisc, we respect proper
XPS setting and remove this lock contention.
5.84% [kernel] [k] netem_enqueue
4.83% [kernel] [k] _raw_spin_lock
2.92% [kernel] [k] copy_user_enhanced_fast_string
Current Qdiscs that benefit from this change are :
netem, cbq, fq, hfsc, tbf, htb.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 26 Sep 2014 04:23:13 +0000 (00:23 -0400)]
Merge branch 'gso_send_check'
Tom Herbert says:
====================
net: Eliminate gso_send_check
gso_send_check presents a lot of complexity for what it is being used
for. It seems that there are only two cases where it might be effective:
TCP and UFO paths. In these cases, the gso_send_check function
initializes the TCP or UDP checksum respectively to the pseudo header
checksum so that the checksum computation is appropriately offloaded or
computed in the gso_segment functions. The gso_send_check functions
are only called from dev.c in skb_mac_gso_segment when ip_summed !=
CHECKSUM_PARTIAL (which seems very unlikely in TCP case). We can move
the logic of this into the respective gso_segment functions where the
checksum is initialized if ip_summed != CHECKSUM_PARTIAL.
With the above cases handled, gso_send_check is no longer needed, so
we can remove all uses of it and the fields in the offload callbacks.
With this change, ip_summed in the skb should be preserved though all
the layers of gso_segment calls.
In follow-on patches, we may be able to remove the check setup code in
tcp_gso_segment if we can guarantee that ip_summed will always be
CHECKSUM_PARTIAL (verify all paths and probably add an assert in
tcp_gro_segment).
Tested these patches by:
- netperf TCP_STREAM test with GSO enabled
- Forced ip_summed != CHECKSUM_PARTIAL with above
- Ran UDP_RR with 10000 request size over GRE tunnel. This exercised
UFO path.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sat, 20 Sep 2014 21:52:30 +0000 (14:52 -0700)]
net: Remove gso_send_check as an offload callback
The send_check logic was only interesting in cases of TCP offload and
UDP UFO where the checksum needed to be initialized to the pseudo
header checksum. Now we've moved that logic into the related
gso_segment functions so gso_send_check is no longer needed.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sat, 20 Sep 2014 21:52:29 +0000 (14:52 -0700)]
udp: move logic out of udp[46]_ufo_send_check
In udp[46]_ufo_send_check the UDP checksum initialized to the pseudo
header checksum. We can move this logic into udp[46]_ufo_fragment.
After this change udp[64]_ufo_send_check is a no-op.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sat, 20 Sep 2014 21:52:28 +0000 (14:52 -0700)]
tcp: move logic out of tcp_v[64]_gso_send_check
In tcp_v[46]_gso_send_check the TCP checksum is initialized to the
pseudo header checksum using __tcp_v[46]_send_check. We can move this
logic into new tcp[46]_gso_segment functions to be done when
ip_summed != CHECKSUM_PARTIAL (ip_summed == CHECKSUM_PARTIAL should be
the common case, possibly always true when taking GSO path). After this
change tcp_v[46]_gso_send_check is no-op.
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 26 Sep 2014 04:13:06 +0000 (00:13 -0400)]
Merge branch 'stmmac'
Beniamino Galvani says:
====================
net: stmmac glue layer for Amlogic Meson SoCs
the Ethernet controller available in Amlogic Meson6 and Meson8 SoCs is
a Synopsys DesignWare MAC IP core, already supported by the stmmac
driver.
These patches add a glue layer to the driver for the platform-specific
settings required by the Amlogic variant.
This has been tested on a Amlogic S802 device with the initial Meson
support submitted by Carlo Caione [1].
[1] http://lwn.net/Articles/612000/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Beniamino Galvani [Sat, 20 Sep 2014 13:29:17 +0000 (15:29 +0200)]
net: stmmac: meson: document device tree bindings
Add the device tree bindings documentation for the Amlogic Meson
variant of the Synopsys DesignWare MAC.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Beniamino Galvani [Sat, 20 Sep 2014 13:29:16 +0000 (15:29 +0200)]
net: stmmac: add Amlogic Meson glue layer
The Ethernet controller available in Meson6 and Meson8 SoCs is a
Synopsys DesignWare MAC IP core, already supported by the stmmac
driver.
This glue layer implements some platform-specific settings needed by
the Amlogic variant.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 24 Sep 2014 20:48:32 +0000 (16:48 -0400)]
Merge git://git./linux/kernel/git/davem/net
Linus Torvalds [Wed, 24 Sep 2014 19:45:24 +0000 (12:45 -0700)]
Merge git://git./linux/kernel/git/davem/net
Pull networking fixes from David Miller:
"Here is a quick pull request primarily meant to address the deconfig
fallout from changing SCSI_NETLINK from being used via 'select' to
being used via 'depends'.
I applied a set of 5 patches written by Michal Marek, and then I
carefully audited all of the remaining config files, basically:
1) I scanned every arch config file, and if it mentioned CONFIG_INET
or CONFIG_UNIX, I made sure it had CONFIG_NET=y
2) After that, I scanned every arch config file, and if it did not
have CONFIG_NET=y I made sure it did not reference any networking
config options.
Finally, we have some late breaking wireless fixes in here from John
Linville and co"
[ And there's a sparc bpf fix snuck in too ]
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
sparc: bpf_jit: fix loads from negative offsets
parisc: Update defconfigs which were missing CONFIG_NET.
powerpc: Update defconfigs which were missing CONFIG_NET.
s390: Update defconfigs which were missing CONFIG_NET.
mips: Update some more defconfigs which were missing CONFIG_NET.
sparc: Set CONFIG_NET=y in defconfigs
sh: Set CONFIG_NET=y in defconfigs
powerpc: Set CONFIG_NET=y in defconfigs
parisc: Set CONFIG_NET=y in defconfigs
mips: Set CONFIG_NET=y in defconfigs
brcmfmac: Fix off by one bug in brcmf_count_20mhz_channels()
ath9k: Fix NULL pointer dereference on early irq
net: rfkill: gpio: Fix clock status
NFC: st21nfca: Fix potential depmod dependency cycle
NFC: st21nfcb: Fix depmod dependency cycle
NFC: microread: Potential overflows in microread_target_discovered()
Alexei Starovoitov [Tue, 23 Sep 2014 20:50:10 +0000 (13:50 -0700)]
sparc: bpf_jit: fix loads from negative offsets
- fix BPF_LD|ABS|IND from negative offsets:
make sure to sign extend lower 32 bits in 64-bit register
before calling C helpers from JITed code, otherwise 'int k'
argument of bpf_internal_load_pointer_neg_helper() function
will be added as large unsigned integer, causing packet size
check to trigger and abort the program.
It's worth noting that JITed code for 'A = A op K' will affect
upper 32 bits differently depending whether K is simm13 or not.
Since small constants are sign extended, whereas large constants
are stored in temp register and zero extended.
That is ok and we don't have to pay a penalty of sign extension
for every sethi, since all classic BPF instructions have 32-bit
semantics and we only need to set correct upper bits when
transitioning from JITed code into C.
- though instructions 'A &= 0' and 'A *= 0' are odd, JIT compiler
should not optimize them out
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 24 Sep 2014 19:00:12 +0000 (15:00 -0400)]
Merge tag 'master-2014-09-23' of git://git./linux/kernel/git/linville/wireless
John W. Linville says:
====================
pull request: wireless 2014-09-23
Please consider pulling this one last batch of fixes intended for the 3.17 stream!
For the NFC bits, Samuel says:
"Hopefully not too late for a handful of NFC fixes:
- 2 potential build failures for ST21NFCA and ST21NFCB, triggered by a
depmod dependenyc cycle.
- One potential buffer overflow in the microread driver."
On top of that...
Emil Goode provides a fix for a brcmfmac off-by-one regression which
was introduced in the 3.17 cycle.
Loic Poulain fixes a polarity mismatch for a variable assignment
inside of rfkill-gpio.
Wojciech Dubowik prevents a NULL pointer dereference in ath9k.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 24 Sep 2014 17:53:53 +0000 (13:53 -0400)]
parisc: Update defconfigs which were missing CONFIG_NET.
Commit
df568d8e ("scsi: Use 'depends' with LIBFC instead of
'select'.") removed what happened to be the only instance of 'select
NET'. Defconfigs that were relying on the select now lack networking
support.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 24 Sep 2014 17:53:43 +0000 (13:53 -0400)]
powerpc: Update defconfigs which were missing CONFIG_NET.
Commit
df568d8e ("scsi: Use 'depends' with LIBFC instead of
'select'.") removed what happened to be the only instance of 'select
NET'. Defconfigs that were relying on the select now lack networking
support.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 24 Sep 2014 17:44:32 +0000 (13:44 -0400)]
s390: Update defconfigs which were missing CONFIG_NET.
Commit
df568d8e ("scsi: Use 'depends' with LIBFC instead of
'select'.") removed what happened to be the only instance of 'select
NET'. Defconfigs that were relying on the select now lack networking
support.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 24 Sep 2014 17:44:16 +0000 (13:44 -0400)]
mips: Update some more defconfigs which were missing CONFIG_NET.
Commit
df568d8e ("scsi: Use 'depends' with LIBFC instead of
'select'.") removed what happened to be the only instance of 'select
NET'. Defconfigs that were relying on the select now lack networking
support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Marek [Tue, 23 Sep 2014 15:44:04 +0000 (17:44 +0200)]
sparc: Set CONFIG_NET=y in defconfigs
Commit
5d6be6a5 ("scsi_netlink : Make SCSI_NETLINK dependent on NET
instead of selecting NET") removed what happened to be the only instance
of 'select NET'. Defconfigs that were relying on the select now lack
networking support.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Marek [Tue, 23 Sep 2014 15:44:03 +0000 (17:44 +0200)]
sh: Set CONFIG_NET=y in defconfigs
Commit
5d6be6a5 ("scsi_netlink : Make SCSI_NETLINK dependent on NET
instead of selecting NET") removed what happened to be the only instance
of 'select NET'. Defconfigs that were relying on the select now lack
networking support.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: linux-sh@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Marek [Tue, 23 Sep 2014 15:44:02 +0000 (17:44 +0200)]
powerpc: Set CONFIG_NET=y in defconfigs
Commit
5d6be6a5 ("scsi_netlink : Make SCSI_NETLINK dependent on NET
instead of selecting NET") removed what happened to be the only instance
of 'select NET'. Defconfigs that were relying on the select now lack
networking support.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Marek [Tue, 23 Sep 2014 15:44:01 +0000 (17:44 +0200)]
parisc: Set CONFIG_NET=y in defconfigs
Commit
5d6be6a5 ("scsi_netlink : Make SCSI_NETLINK dependent on NET
instead of selecting NET") removed what happened to be the only instance
of 'select NET'. Defconfigs that were relying on the select now lack
networking support.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Marek [Tue, 23 Sep 2014 15:44:00 +0000 (17:44 +0200)]
mips: Set CONFIG_NET=y in defconfigs
Commit
5d6be6a5 ("scsi_netlink : Make SCSI_NETLINK dependent on NET
instead of selecting NET") removed what happened to be the only instance
of 'select NET'. Defconfigs that were relying on the select now lack
networking support.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: linux-mips@linux-mips.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Wed, 24 Sep 2014 16:51:50 +0000 (09:51 -0700)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull one last block fix from Jens Axboe:
"We've had an issue with scsi-mq where probing takes forever. This was
bisected down to the percpu changes for blk_mq_queue_enter(), and the
fact we now suffer an RCU grace period when killing a queue. SCSI
creates and destroys tons of queues, so this let to 10s of seconds of
stalls at boot for some.
Tejun has a real fix for this, but it's too involved for 3.17. So
this is a temporary workaround to expedite the queue killing until we
can fold in the real fix for 3.18 when that merge window opens"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe
Linus Torvalds [Wed, 24 Sep 2014 16:46:29 +0000 (09:46 -0700)]
Merge tag 'pci-v3.17-fixes-3' of git://git./linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
"Here are a few fixes that should be in v3.17.
- Reverting "Don't scan random busses" covers up a CardBus regression
having to do with allocating CardBus bus numbers.
- Reverting "Make sure bus numbers stay within parents bounds" covers
up an ACPI _CRS bug that makes us reconfigure a bridge, causing a
broken device behind it to stop responding.
- The pciehp timeout change fixes some code we added in v3.17.
Without the fix, we can send a new hotplug command too early,
before the timeout has expired.
I hope for better fixes for the reverts, but those will have to come
after v3.17"
* tag 'pci-v3.17-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: pciehp: Fix pcie_wait_cmd() timeout
Revert "PCI: Make sure bus number resources stay within their parents bounds"
Revert "PCI: Don't scan random busses in pci_scan_bridge()"
Linus Torvalds [Wed, 24 Sep 2014 16:37:35 +0000 (09:37 -0700)]
Merge git://git./linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
"This fixes three issues:
- if ccp is loaded on a machine without ccp, it will incorrectly
activate causing all requests to fail. Fixed by preventing ccp
from loading if hardware isn't available.
- not all IRQs were enabled for the qat driver, leading to potential
stalls when it is used
- disabled buggy AVX CTR implementation in aesni"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: aesni - disable "by8" AVX CTR optimization
crypto: ccp - Check for CCP before registering crypto algs
crypto: qat - Enable all 32 IRQs
Linus Torvalds [Wed, 24 Sep 2014 16:03:43 +0000 (09:03 -0700)]
Merge tag 'media/v3.17-rc7' of git://git./linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab:
"For some last time fixes:
- a regression detected on Kernel 3.16 related to VBI Teletext
application breakage on drivers using videobuf2 (see
https://bugzilla.kernel.org/show_bug.cgi?id=84401). The bug was
noticed on saa7134 (migrated to VB2 on 3.16), but also affects
em28xx (migrated on 3.9 to VB2);
- two additional sanity checks at videobuf2;
- two fixups to restore proper VBI support at the em28xx driver;
- two Kernel oops fixups (at cx24123 and cx2341x drivers);
- a bug at adv7604 where an if was doing just the opposite as it
would be expected;
- some documentation fixups to match the behavior defined at the
Kernel"
* tag 'media/v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] em28xx-v4l: get rid of field "users" in struct em28xx_v4l2"
[media] em28xx: fix VBI handling logic
[media] DocBook media: improve the poll() documentation
[media] DocBook media: fix the poll() 'no QBUF' documentation
[media] vb2: fix VBI/poll regression
[media] cx2341x: fix kernel oops
[media] cx24123: fix kernel oops due to missing parent pointer
[media] adv7604: fix inverted condition
[media] media/radio: fix radio-miropcm20.c build with io.h header file
[media] vb2: fix plane index sanity check in vb2_plane_cookie()
[media] DocBook media: update version number and V4L2 changes
[media] DocBook media: fix fieldname in struct v4l2_subdev_selection
[media] vb2: fix vb2 state check when start_streaming fails
[media] videobuf2-core.h: fix comment
[media] videobuf2-core: add comments before the WARN_ON
[media] videobuf2-dma-sg: fix for wrong GFP mask to sg_alloc_table_from_pages
Linus Torvalds [Wed, 24 Sep 2014 15:53:33 +0000 (08:53 -0700)]
Merge tag 'md/3.17-more-fixes' of git://git.neil.brown.name/md
Pull bugfixes for md/raid1 from Neil Brown:
"It is amazing how much easier it is to find bugs when you know one is
there. Two bug reports resulted in finding 7 bugs!
All are tagged for -stable. Those that can't cause (rare) data
corruption, cause lockups.
Particularly, but not only, fixing new "resync" code"
* tag 'md/3.17-more-fixes' of git://git.neil.brown.name/md:
md/raid1: fix_read_error should act on all non-faulty devices.
md/raid1: count resync requests in nr_pending.
md/raid1: update next_resync under resync_lock.
md/raid1: Don't use next_resync to determine how far resync has progressed
md/raid1: make sure resync waits for conflicting writes to complete.
md/raid1: clean up request counts properly in close_sync()
md/raid1: be more cautious where we read-balance during resync.
md/raid1: intialise start_next_window for READ case to avoid hang
Tejun Heo [Tue, 23 Sep 2014 19:24:32 +0000 (15:24 -0400)]
blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe
blk-mq uses percpu_ref for its usage counter which tracks the number
of in-flight commands and used to synchronously drain the queue on
freeze. percpu_ref shutdown takes measureable wallclock time as it
involves a sched RCU grace period. This means that draining a blk-mq
takes measureable wallclock time. One would think that this shouldn't
matter as queue shutdown should be a rare event which takes place
asynchronously w.r.t. userland.
Unfortunately, SCSI probing involves synchronously setting up and then
tearing down a lot of request_queues back-to-back for non-existent
LUNs. This means that SCSI probing may take more than ten seconds
when scsi-mq is used.
This will be properly fixed by implementing a mechanism to keep
q->mq_usage_counter in atomic mode till genhd registration; however,
that involves rather big updates to percpu_ref which is difficult to
apply late in the devel cycle (v3.17-rc6 at the moment). As a
stop-gap measure till the proper fix can be implemented in the next
cycle, this patch introduces __percpu_ref_kill_expedited() and makes
blk_mq_freeze_queue() use it. This is heavy-handed but should work
for testing the experimental SCSI blk-mq implementation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Christoph Hellwig <hch@infradead.org>
Link: http://lkml.kernel.org/g/20140919113815.GA10791@lst.de
Fixes: add703fda981 ("blk-mq: use percpu_ref for mq usage count")
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Tested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Mathias Krause [Tue, 23 Sep 2014 20:31:07 +0000 (22:31 +0200)]
crypto: aesni - disable "by8" AVX CTR optimization
The "by8" implementation introduced in commit
22cddcc7df8f ("crypto: aes
- AES CTR x86_64 "by8" AVX optimization") is failing crypto tests as it
handles counter block overflows differently. It only accounts the right
most 32 bit as a counter -- not the whole block as all other
implementations do. This makes it fail the cryptomgr test #4 that
specifically tests this corner case.
As we're quite late in the release cycle, just disable the "by8" variant
for now.
Reported-by: Romain Francoise <romain@orebokech.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Chandramouli Narayanan <mouli@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tom Lendacky [Fri, 5 Sep 2014 15:31:09 +0000 (10:31 -0500)]
crypto: ccp - Check for CCP before registering crypto algs
If the ccp is built as a built-in module, then ccp-crypto (whether
built as a module or a built-in module) will be able to load and
it will register its crypto algorithms. If the system does not have
a CCP this will result in -ENODEV being returned whenever a command
is attempted to be queued by the registered crypto algorithms.
Add an API, ccp_present(), that checks for the presence of a CCP
on the system. The ccp-crypto module can use this to determine if it
should register it's crypto alogorithms.
Cc: stable@vger.kernel.org
Reported-by: Scot Doyle <lkml14@scotdoyle.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Scot Doyle <lkml14@scotdoyle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Linus Torvalds [Tue, 23 Sep 2014 23:47:34 +0000 (16:47 -0700)]
Merge tag 'rdma-for-linus' of git://git./linux/kernel/git/roland/infiniband
Pull infiniband/rdma fixes from Roland Dreier:
"Last late set of InfiniBand/RDMA fixes for 3.17:
- fixes for the new memory region re-registration support
- iSER initiator error path fixes
- grab bag of small fixes for the qib and ocrdma hardware drivers
- larger set of fixes for mlx4, especially in RoCE mode"
* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (26 commits)
IB/mlx4: Fix VF mac handling in RoCE
IB/mlx4: Do not allow APM under RoCE
IB/mlx4: Don't update QP1 in native mode
IB/mlx4: Avoid accessing netdevice when building RoCE qp1 header
mlx4: Fix mlx4 reg/unreg mac to work properly with 0-mac addresses
IB/core: When marshaling uverbs path, clear unused fields
IB/mlx4: Avoid executing gid task when device is being removed
IB/mlx4: Fix lockdep splat for the iboe lock
IB/mlx4: Get upper dev addresses as RoCE GIDs when port comes up
IB/mlx4: Reorder steps in RoCE GID table initialization
IB/mlx4: Don't duplicate the default RoCE GID
IB/mlx4: Avoid null pointer dereference in mlx4_ib_scan_netdevs()
IB/iser: Bump version to 1.4.1
IB/iser: Allow bind only when connection state is UP
IB/iser: Fix RX/TX CQ resource leak on error flow
RDMA/ocrdma: Use right macro in query AH
RDMA/ocrdma: Resolve L2 address when creating user AH
mlx4: Correct error flows in rereg_mr
IB/qib: Correct reference counting in debugfs qp_stats
IPoIB: Remove unnecessary port query
...
Linus Torvalds [Tue, 23 Sep 2014 21:47:11 +0000 (14:47 -0700)]
Merge tag 'sound-3.17-rc7' of git://git./linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"One fix is about a buggy computation in PCM API function Clemens
spotted out, but the impact must be really small as no one really uses
it in user-space side.
The rest are a trivial fix for a HD-audio model and a USB-audio
device-specific regression fix, so all look fairly safe to apply"
* tag 'sound-3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: snd-usb-caiaq: Fix LED commands for Kore controller
ALSA: pcm: fix fifo_size frame calculation
ALSA: hda - Add fixup model name lookup for Lemote A1205
Linus Torvalds [Tue, 23 Sep 2014 21:45:09 +0000 (14:45 -0700)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull final block fixes from Jens Axboe:
"This week and last we've been fixing some corner cases related to
blk-mq, mostly. I ended up pulling most of that out of for-linus
yesterday, which is why the branch looks fresh. The rest were
postponed for 3.18.
This pull request contains:
- Fix from Christoph, avoiding a stack overflow when FUA insertion
would recursive infinitely.
- Fix from David Hildenbrand on races between the timeout handler and
uninitialized requests. Fixes a real issue that virtio_blk has run
into.
- A few fixes from me:
- Ensure that request deadline/timeout is ordered before the
request is marked as started.
- A potential oops on out-of-memory, when we scale the queue
depth of the device and retry.
- A hang fix on requeue from SCSI, where the hardware queue
would be stopped when we attempt to re-run it (and hence
nothing would happen, stalling progress).
- A fix for commit
2da78092, where the cleanup path was moved
to RCU, but a debug might_sleep() was inadvertently left in
the code. This causes warnings for people"
* 'for-linus' of git://git.kernel.dk/linux-block:
genhd: fix leftover might_sleep() in blk_free_devt()
blk-mq: use blk_mq_start_hw_queues() when running requeue work
blk-mq: fix potential oops on out-of-memory in __blk_mq_alloc_rq_maps()
blk-mq: avoid infinite recursion with the FUA flag
blk-mq: Avoid race condition with uninitialized requests
blk-mq: request deadline must be visible before marking rq as started