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2016-09-22sctp: rename WORD_TRUNC/ROUND macrosMarcelo Ricardo Leitner1-2/+2
To something more meaningful these days, specially because this is working on packet headers or lengths and which are not tied to any CPU arch but to the protocol itself. So, WORD_TRUNC becomes SCTP_TRUNC4 and WORD_ROUND becomes SCTP_PAD4. Reported-by: David Laight <David.Laight@ACULAB.COM> Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-11sctp: avoid refreshing heartbeat timer too oftenMarcelo Ricardo Leitner1-6/+13
Currently on high rate SCTP streams the heartbeat timer refresh can consume quite a lot of resources as timer updates are costly and it contains a random factor, which a) is also costly and b) invalidates mod_timer() optimization for not editing a timer to the same value. It may even cause the timer to be slightly advanced, for no good reason. As suggested by David Laight this patch now removes this timer update from hot path by leaving the timer on and re-evaluating upon its expiration if the heartbeat is still needed or not, similarly to what is done for TCP. If it's not needed anymore the timer is re-scheduled to the new timeout, considering the time already elapsed. For this, we now record the last tx timestamp per transport, updated in the same spots as hb timer was restarted on tx. Also split up sctp_transport_reset_timers into sctp_transport_reset_t3_rtx and sctp_transport_reset_hb_timer, so we can re-arm T3 without re-arming the heartbeat one. On loopback with MTU of 65535 and data chunks with 1636, so that we have a considerable amount of chunks without stressing system calls, netperf -t SCTP_STREAM -l 30, perf looked like this before: Samples: 103K of event 'cpu-clock', Event count (approx.): 25833000000 Overhead Command Shared Object Symbol + 6,15% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string - 5,43% netperf [kernel.vmlinux] [k] _raw_write_unlock_irqrestore - _raw_write_unlock_irqrestore - 96,54% _raw_spin_unlock_irqrestore - 36,14% mod_timer + 97,24% sctp_transport_reset_timers + 2,76% sctp_do_sm + 33,65% __wake_up_sync_key + 28,77% sctp_ulpq_tail_event + 1,40% del_timer - 1,84% mod_timer + 99,03% sctp_transport_reset_timers + 0,97% sctp_do_sm + 1,50% sctp_ulpq_tail_event And after this patch, now with netperf -l 60: Samples: 230K of event 'cpu-clock', Event count (approx.): 57707250000 Overhead Command Shared Object Symbol + 5,65% netperf [kernel.vmlinux] [k] memcpy_erms + 5,59% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string - 5,05% netperf [kernel.vmlinux] [k] _raw_spin_unlock_irqrestore - _raw_spin_unlock_irqrestore + 49,89% __wake_up_sync_key + 45,68% sctp_ulpq_tail_event - 2,85% mod_timer + 76,51% sctp_transport_reset_t3_rtx + 23,49% sctp_do_sm + 1,55% del_timer + 2,50% netperf [sctp] [k] sctp_datamsg_from_user + 2,26% netperf [sctp] [k] sctp_sendmsg Throughput-wise, from 6800mbps without the patch to 7050mbps with it, ~3.7%. Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-20sctp: align MTU to a wordMarcelo Ricardo Leitner1-2/+2
SCTP is a protocol that is aligned to a word (4 bytes). Thus using bare MTU can sometimes return values that are not aligned, like for loopback, which is 65536 but ipv4_mtu() limits that to 65535. This mis-alignment will cause the last non-aligned bytes to never be used and can cause issues with congestion control. So it's better to just consider a lower MTU and keep congestion control calcs saner as they are based on PMTU. Same applies to icmp frag needed messages, which is also fixed by this patch. One other effect of this is the inability to send MTU-sized packet without queueing or fragmentation and without hitting Nagle. As the check performed at sctp_packet_can_append_data(): if (chunk->skb->len + q->out_qlen >= transport->pathmtu - packet->overhead) /* Enough data queued to fill a packet */ return SCTP_XMIT_OK; with the above example of MTU, if there are no other messages queued, one cannot send a packet that just fits one packet (65532 bytes) and without causing DATA chunk fragmentation or a delay. v2: - Added WORD_TRUNC macro Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14sctp: fix the transports round robin issue when init is retransmittedXin Long1-1/+1
prior to this patch, at the beginning if we have two paths in one assoc, they may have the same params other than the last_time_heard, it will try the paths like this: 1st cycle try trans1 fail. then trans2 is selected.(cause it's last_time_heard is after trans1). 2nd cycle: try trans2 fail then trans2 is selected.(cause it's last_time_heard is after trans1). 3rd cycle: try trans2 fail then trans2 is selected.(cause it's last_time_heard is after trans1). .... trans1 will never have change to be selected, which is not what we expect. we should keeping round robin all the paths if they are just added at the beginning. So at first every tranport's last_time_heard should be initialized 0, so that we ensure they have the same value at the beginning, only by this, all the transports could get equal chance to be selected. Then for sctp_trans_elect_best, it should return the trans_next one when *trans == *trans_next, so that we can try next if it fails, but now it always return trans. so we can fix it by exchanging these two params when we calls sctp_trans_elect_tie(). Fixes: 4c47af4d5eb2 ('net: sctp: rework multihoming retransmission path selection to rfc4960') Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-29sctp: remove the dead field of sctp_transportXin Long1-3/+1
After we use refcnt to check if transport is alive, the dead can be removed from sctp_transport. The traversal of transport_addr_list in procfs dump is using list_for_each_entry_rcu, no need to check if it has been freed. sctp_generate_t3_rtx_event and sctp_generate_heartbeat_event is protected by sock lock, it's not necessary to check dead, either. also, the timers are cancelled when sctp_transport_free() is called, that it doesn't wait for refcnt to reach 0 to cancel them. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-29sctp: fix the transport dead race check by using atomic_add_unless on refcntXin Long1-2/+2
Now when __sctp_lookup_association is running in BH, it will try to check if t->dead is set, but meanwhile other CPUs may be freeing this transport and this assoc and if it happens that __sctp_lookup_association checked t->dead a bit too early, it may think that the association is still good while it was already freed. So we fix this race by using atomic_add_unless in sctp_transport_hold. After we get one transport from hashtable, we will hold it only when this transport's refcnt is not 0, so that we can make sure t->asoc cannot be freed before we hold the asoc again. Note that sctp association is not freed using RCU so we can't use atomic_add_unless() with it as it may just be too late for that either. Fixes: 4f0087812648 ("sctp: apply rhashtable api to send/recv path") Reported-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-10remove abs64()Andrew Morton1-1/+1
Switch everything to the new and more capable implementation of abs(). Mainly to give the new abs() a bit of a workout. Cc: Michal Nazarewicz <mina86@mina86.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-01sctp: Fixup v4mapped behaviour to comply with Sock APIJason Gunthorpe1-2/+2
The SCTP socket extensions API document describes the v4mapping option as follows: 8.1.15. Set/Clear IPv4 Mapped Addresses (SCTP_I_WANT_MAPPED_V4_ADDR) This socket option is a Boolean flag which turns on or off the mapping of IPv4 addresses. If this option is turned on, then IPv4 addresses will be mapped to V6 representation. If this option is turned off, then no mapping will be done of V4 addresses and a user will receive both PF_INET6 and PF_INET type addresses on the socket. See [RFC3542] for more details on mapped V6 addresses. This description isn't really in line with what the code does though. Introduce addr_to_user (renamed addr_v4map), which should be called before any sockaddr is passed back to user space. The new function places the sockaddr into the correct format depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. Audit all places that touched v4mapped and either sanely construct a v4 or v6 address then call addr_to_user, or drop the unnecessary v4mapped check entirely. Audit all places that call addr_to_user and verify they are on a sycall return path. Add a custom getname that formats the address properly. Several bugs are addressed: - SCTP_I_WANT_MAPPED_V4_ADDR=0 often returned garbage for addresses to user space - The addr_len returned from recvmsg was not correct when returning AF_INET on a v6 socket - flowlabel and scope_id were not zerod when promoting a v4 to v6 - Some syscalls like bind and connect behaved differently depending on v4mapped Tested bind, getpeername, getsockname, connect, and recvmsg for proper behaviour in v4mapped = 1 and 0 cases. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-03net: sctp: improve timer slack calculation for transport HBsDaniel Borkmann1-8/+9
RFC4960, section 8.3 says: On an idle destination address that is allowed to heartbeat, it is recommended that a HEARTBEAT chunk is sent once per RTO of that destination address plus the protocol parameter 'HB.interval', with jittering of +/- 50% of the RTO value, and exponential backoff of the RTO if the previous HEARTBEAT is unanswered. Currently, we calculate jitter via sctp_jitter() function first, and then add its result to the current RTO for the new timeout: TMO = RTO + (RAND() % RTO) - (RTO / 2) `------------------------^-=> sctp_jitter() Instead, we can just simplify all this by directly calculating: TMO = (RTO / 2) + (RAND() % RTO) With the help of prandom_u32_max(), we don't need to open code our own global PRNG, but can instead just make use of the per CPU implementation of prandom with better quality numbers. Also, we can now spare us the conditional for divide by zero check since no div or mod operation needs to be used. Note that prandom_u32_max() won't emit the same result as a mod operation, but we really don't care here as we only want to have a random number scaled into RTO interval. Note, exponential RTO backoff is handeled elsewhere, namely in sctp_do_8_2_transport_strike(). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-11net: sctp: migrate most recently used transport to ktimeDaniel Borkmann1-1/+1
Be more precise in transport path selection and use ktime helpers instead of jiffies to compare and pick the better primary and secondary recently used transports. This also avoids any side-effects during a possible roll-over, and could lead to better path decision-making. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-14net: remove unnecessary return'sstephen hemminger1-1/+0
One of my pet coding style peeves is the practice of adding extra return; at the end of function. Kill several instances of this in network code. I suppose some coccinelle wizardy could do this automatically. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Merge 'net' into 'net-next' to get the AF_PACKET bug fix that Daniel's direct transmit changes depend upon. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06sctp: Fix FSF address in file headersJeff Kirsher1-3/+2
Several files refer to an old address for the Free Software Foundation in the file header comment. Resolve by replacing the address with the URL <http://www.gnu.org/licenses/> so that we do not have to keep updating the header comments anytime the address changes. CC: Vlad Yasevich <vyasevich@gmail.com> CC: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06sctp: disable max_burst when the max_burst is 0wangweidong1-1/+1
As Michael pointed out that when max_burst is 0, it just disable max_burst. It declared in rfc6458#section-8.1.24. so add the check in sctp_transport_burst_limited, when it 0, just do nothing. Reviewed-by: Daniel Borkmann <dborkman@redhat.com> Suggested-by: Vlad Yasevich <vyasevich@gmail.com> Suggested-by: Michael Tuexen <Michael.Tuexen@lurchi.franken.de> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+2
2013-08-13net: sctp: sctp_transport_destroy{, _rcu}: fix potential pointer corruptionDaniel Borkmann1-2/+2
Probably this one is quite unlikely to be triggered, but it's more safe to do the call_rcu() at the end after we have dropped the reference on the asoc and freed sctp packet chunks. The reason why is because in sctp_transport_destroy_rcu() the transport is being kfree()'d, and if we're unlucky enough we could run into corrupted pointers. Probably that's more of theoretical nature, but it's safer to have this simple fix. Introduced by commit 8c98653f ("sctp: sctp_close: fix release of bindings for deferred call_rcu's"). I also did the 8c98653f regression test and it's fine that way. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09net: sctp: trivial: update bug report in header commentDaniel Borkmann1-6/+0
With the restructuring of the lksctp.org site, we only allow bug reports through the SCTP mailing list linux-sctp@vger.kernel.org, not via SF, as SF is only used for web hosting and nothing more. While at it, also remove the obvious statement that bugs will be fixed and incooperated into the kernel. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-25net: sctp: trivial: update mailing list addressDaniel Borkmann1-1/+1
The SCTP mailing list address to send patches or questions to is linux-sctp@vger.kernel.org and not lksctp-developers@lists.sourceforge.net anymore. Therefore, update all occurences. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-02net: sctp: rework debugging framework to use pr_debug and friendsDaniel Borkmann1-25/+24
We should get rid of all own SCTP debug printk macros and use the ones that the kernel offers anyway instead. This makes the code more readable and conform to the kernel code, and offers all the features of dynamic debbuging that pr_debug() et al has, such as only turning on/off portions of debug messages at runtime through debugfs. The runtime cost of having CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing, is negligible [1]. If kernel debugging is completly turned off, then these statements will also compile into "empty" functions. While we're at it, we also need to change the Kconfig option as it /now/ only refers to the ifdef'ed code portions in outqueue.c that enable further debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code was enabled with this Kconfig option and has now been removed, we transform those code parts into WARNs resp. where appropriate BUG_ONs so that those bugs can be more easily detected as probably not many people have SCTP debugging permanently turned on. To turn on all SCTP debugging, the following steps are needed: # mount -t debugfs none /sys/kernel/debug # echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control This can be done more fine-grained on a per file, per line basis and others as described in [2]. [1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf [2] Documentation/dynamic-debug-howto.txt Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-18net: sctp: get rid of t_new macro for kzallocDaniel Borkmann1-1/+1
t_new rather obfuscates things where everyone else is using actual function names instead of that macro, so replace it with kzalloc, which is the function t_new wraps. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17net: sctp: sctp_transport: remove unused variableDaniel Borkmann1-1/+0
sctp_transport's member 'malloced' is set to 1, never evaluated and the structure is kfreed anyway. So just remove it. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04net: remove redundant check for timer pending state before del_timerYing Xue1-7/+4
As in del_timer() there has already placed a timer_pending() function to check whether the timer to be deleted is pending or not, it's unnecessary to check timer pending state again before del_timer() is called. Signed-off-by: Ying Xue <ying.xue@windriver.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04sctp: sctp_close: fix release of bindings for deferred call_rcu'sDaniel Borkmann1-4/+5
It seems due to RCU usage, i.e. within SCTP's address binding list, a, say, ``behavioral change'' was introduced which does actually not conform to the RFC anymore. In particular consider the following (fictional) scenario to demonstrate this: do: Two SOCK_SEQPACKET-style sockets are opened (S1, S2) S1 is bound to 127.0.0.1, port 1024 [server] S2 is bound to 127.0.0.1, port 1025 [client] listen(2) is invoked on S1 From S2 we call one sendmsg(2) with msg.msg_name and msg.msg_namelen parameters set to the server's address S1, S2 are closed goto do The first pass of this loop passes successful, while the second round fails during binding of S1 (address still in use). What is happening? In the first round, the initial handshake is being done, and, at the time close(2) is called on S1, a non-graceful shutdown is performed via ABORT since in S1's receive queue an unprocessed packet is present, thus stating an error condition. This can be considered as a correct behavior. During close also all bound addresses are freed, thus nothing *must* be active anymore. In reference to RFC2960: After checking the Verification Tag, the receiving endpoint shall remove the association from its record, and shall report the termination to its upper layer. (9.1 Abort of an Association) Also, no half-open states are supported, thus after an ungraceful shutdown, we leave nothing behind. However, this seems not to be happening though. In a real-world scenario, this is exactly where it breaks the lksctp-tools functional test suite, *for instance*: ./test_sockopt test_sockopt.c 1 PASS : getsockopt(SCTP_STATUS) on a socket with no assoc test_sockopt.c 2 PASS : getsockopt(SCTP_STATUS) test_sockopt.c 3 PASS : getsockopt(SCTP_STATUS) with invalid associd test_sockopt.c 4 PASS : getsockopt(SCTP_STATUS) with NULL associd test_sockopt.c 5 BROK : bind: Address already in use The underlying problem is that sctp_endpoint_destroy() hasn't been triggered yet while the next bind attempt is being done. It will be triggered eventually (but too late) by sctp_transport_destroy_rcu() after one RCU grace period: sctp_transport_destroy() sctp_transport_destroy_rcu() ----. sctp_association_put() [*] <--+--> sctp_packet_free() sctp_association_destroy() [...] sctp_endpoint_put() skb->destructor sctp_endpoint_destroy() sctp_wfree() sctp_bind_addr_free() sctp_association_put() [*] Thus, we move out the condition with sctp_association_put() as well as the sctp_packet_free() invocation and the issue can be solved. We also better free the SCTP chunks first before putting the ref of the association. With this patch, the example above (which simulates a similar scenario as in the implementation of this test case) and therefore also the test suite run successfully through. Tested by myself. Cc: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-07sctp: Add RCU protection to assoc->transport_addr_listThomas Graf1-5/+13
peer.transport_addr_list is currently only protected by sk_sock which is inpractical to acquire for procfs dumping purposes. This patch adds RCU protection allowing for the procfs readers to enter RCU read-side critical sections. Modification of the list continues to be serialized via sk_lock. V2: Use list_del_rcu() in sctp_association_free() to be safe Skip transports marked dead when dumping for procfs Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Thomas Graf <tgraf@suug.ch> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03sctp: Add support to per-association statistics via a new ↵Michele Baldessari1-0/+2
SCTP_GET_ASSOC_STATS call The current SCTP stack is lacking a mechanism to have per association statistics. This is an implementation modeled after OpenSolaris' SCTP_GET_ASSOC_STATS. Userspace part will follow on lksctp if/when there is a general ACK on this. V4: - Move ipackets++ before q->immediate.func() for consistency reasons - Move sctp_max_rto() at the end of sctp_transport_update_rto() to avoid returning bogus RTO values - return asoc->rto_min when max_obs_rto value has not changed V3: - Increase ictrlchunks in sctp_assoc_bh_rcv() as well - Move ipackets++ to sctp_inq_push() - return 0 when no rto updates took place since the last call V2: - Implement partial retrieval of stat struct to cope for future expansion - Kill the rtxpackets counter as it cannot be precise anyway - Rename outseqtsns to outofseqtsns to make it clearer that these are out of sequence unexpected TSNs - Move asoc->ipackets++ under a lock to avoid potential miscounts - Fold asoc->opackets++ into the already existing asoc check - Kill unneeded (q->asoc) test when increasing rtxchunks - Do not count octrlchunks if sending failed (SCTP_XMIT_OK != 0) - Don't count SHUTDOWNs as SACKs - Move SCTP_GET_ASSOC_STATS to the private space API - Adjust the len check in sctp_getsockopt_assoc_stats() to allow for future struct growth - Move association statistics in their own struct - Update idupchunks when we send a SACK with dup TSNs - return min_rto in max_rto when RTO has not changed. Also return the transport when max_rto last changed. Signed-off: Michele Baldessari <michele@acksyn.org> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-28sctp: Error in calculation of RTTvarSchoch Christian1-1/+1
The calculation of RTTVAR involves the subtraction of two unsigned numbers which may causes rollover and results in very high values of RTTVAR when RTT > SRTT. With this patch it is possible to set RTOmin = 1 to get the minimum of RTO at 4 times the clock granularity. Change Notes: v2) *Replaced abs() by abs64() and long by __s64, changed patch description. Signed-off-by: Christian Schoch <e0326715@student.tuwien.ac.at> CC: Vlad Yasevich <vyasevich@gmail.com> CC: Sridhar Samudrala <sri@us.ibm.com> CC: Neil Horman <nhorman@tuxdriver.com> CC: linux-sctp@vger.kernel.org Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-15sctp: Make sysctl tunables per netEric W. Biederman1-7/+8
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-15sctp: Push struct net down into sctp_transport_initEric W. Biederman1-3/+5
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-23Merge branch 'kill_rtcache'David S. Miller1-1/+1
The ipv4 routing cache is non-deterministic, performance wise, and is subject to reasonably easy to launch denial of service attacks. The routing cache works great for well behaved traffic, and the world was a much friendlier place when the tradeoffs that led to the routing cache's design were considered. What it boils down to is that the performance of the routing cache is a product of the traffic patterns seen by a system rather than being a product of the contents of the routing tables. The former of which is controllable by external entitites. Even for "well behaved" legitimate traffic, high volume sites can see hit rates in the routing cache of only ~%10. The general flow of this patch series is that first the routing cache is removed. We build a completely new rtable entry every lookup request. Next we make some simplifications due to the fact that removing the routing cache causes several members of struct rtable to become no longer necessary. Then we need to make some amends such that we can legally cache pre-constructed routes in the FIB nexthops. Firstly, we need to invalidate routes which are hit with nexthop exceptions. Secondly we have to change the semantics of rt->rt_gateway such that zero means that the destination is on-link and non-zero otherwise. Now that the preparations are ready, we start caching precomputed routes in the FIB nexthops. Output and input routes need different kinds of care when determining if we can legally do such caching or not. The details are in the commit log messages for those changes. The patch series then winds down with some more struct rtable simplifications and other tidy ups that remove unnecessary overhead. On a SPARC-T3 output route lookups are ~876 cycles. Input route lookups are ~1169 cycles with rpfilter disabled, and about ~1468 cycles with rpfilter enabled. These measurements were taken with the kbench_mod test module in the net_test_tools GIT tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net_test_tools.git That GIT tree also includes a udpflood tester tool and stresses route lookups on packet output. For example, on the same SPARC-T3 system we can run: time ./udpflood -l 10000000 10.2.2.11 with routing cache: real 1m21.955s user 0m6.530s sys 1m15.390s without routing cache: real 1m31.678s user 0m6.520s sys 1m25.140s Performance undoubtedly can easily be improved further. For example fib_table_lookup() performs a lot of excessive computations with all the masking and shifting, some of it conditionalized to deal with edge cases. Also, Eric's no-ref optimization for input route lookups can be re-instated for the FIB nexthop caching code path. I would be really pleased if someone would work on that. In fact anyone suitable motivated can just fire up perf on the loading of the test net_test_tools benchmark kernel module. I spend much of my time going: bash# perf record insmod ./kbench_mod.ko dst=172.30.42.22 src=74.128.0.1 iif=2 bash# perf report Thanks to helpful feedback from Joe Perches, Eric Dumazet, Ben Hutchings, and others. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22sctp: Implement quick failover draft from tsvwgNeil Horman1-1/+3
I've seen several attempts recently made to do quick failover of sctp transports by reducing various retransmit timers and counters. While its possible to implement a faster failover on multihomed sctp associations, its not particularly robust, in that it can lead to unneeded retransmits, as well as false connection failures due to intermittent latency on a network. Instead, lets implement the new ietf quick failover draft found here: http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05 This will let the sctp stack identify transports that have had a small number of errors, and avoid using them quickly until their reliability can be re-established. I've tested this out on two virt guests connected via multiple isolated virt networks and believe its in compliance with the above draft and works well. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Vlad Yasevich <vyasevich@gmail.com> CC: Sridhar Samudrala <sri@us.ibm.com> CC: "David S. Miller" <davem@davemloft.net> CC: linux-sctp@vger.kernel.org CC: joe@perches.com Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-21net: Document dst->obsolete better.David S. Miller1-1/+1
Add a big comment explaining how the field works, and use defines instead of magic constants for the values assigned to it. Suggested by Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()David S. Miller1-1/+1
This will be used so that we can compose a full flow key. Even though we have a route in this context, we need more. In the future the routes will be without destination address, source address, etc. keying. One ipv4 route will cover entire subnets, etc. In this environment we have to have a way to possess persistent storage for redirects and PMTU information. This persistent storage will exist in the FIB tables, and that's why we'll need to be able to rebuild a full lookup flow key here. Using that flow key will do a fib_lookup() and create/update the persistent entry. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-16sctp: Adjust PMTU updates to accomodate route invalidation.David S. Miller1-2/+10
This adjusts the call to dst_ops->update_pmtu() so that we can transparently handle the fact that, in the future, the dst itself can be invalidated by the PMTU update (when we have non-host routes cached in sockets). Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-01sctp: be more restrictive in transport selection on bundled sacksNeil Horman1-0/+2
It was noticed recently that when we send data on a transport, its possible that we might bundle a sack that arrived on a different transport. While this isn't a major problem, it does go against the SHOULD requirement in section 6.4 of RFC 2960: An endpoint SHOULD transmit reply chunks (e.g., SACK, HEARTBEAT ACK, etc.) to the same destination transport address from which it received the DATA or control chunk to which it is replying. This rule should also be followed if the endpoint is bundling DATA chunks together with the reply chunk. This patch seeks to correct that. It restricts the bundling of sack operations to only those transports which have moved the ctsn of the association forward since the last sack. By doing this we guarantee that we only bundle outbound saks on a transport that has received a chunk since the last sack. This brings us into stricter compliance with the RFC. Vlad had initially suggested that we strictly allow only sack bundling on the transport that last moved the ctsn forward. While this makes sense, I was concerned that doing so prevented us from bundling in the case where we had received chunks that moved the ctsn on multiple transports. In those cases, the RFC allows us to select any of the transports having received chunks to bundle the sack on. so I've modified the approach to allow for that, by adding a state variable to each transport that tracks weather it has moved the ctsn since the last sack. This I think keeps our behavior (and performance), close enough to our current profile that I think we can do this without a sysctl knob to enable/disable it. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Vlad Yaseivch <vyasevich@gmail.com> CC: David S. Miller <davem@davemloft.net> CC: linux-sctp@vger.kernel.org Reported-by: Michele Baldessari <michele@redhat.com> Reported-by: sorin serban <sserban@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-11sctp: check cached dst before using itNicolas Dichtel1-17/+0
dst_check() will take care of SA (and obsolete field), hence IPsec rekeying scenario is taken into account. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Vlad Yaseivch <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-09sctp: fasthandoff with ASCONF at mobile-nodeMichio Honda1-0/+16
Fast retransmission after changing the last address with ASCONF negotiation Signed-off-by: Michio Honda <micchie@sfc.wide.ad.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-09sctp: Store a flowi in transports to provide persistent keying.David S. Miller1-6/+3
Several future simplifications are possible now because of this. For example, the sctp_addr unions can simply refer directly to the flowi information. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28sctp: clean up route lookup callsVlad Yasevich1-13/+10
Change the call to take the transport parameter and set the cached 'dst' appropriately inside the get_dst() function calls. This will allow us in the future to clean up source address storage as well. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28sctp: remove useless arguments from get_saddr() callVlad Yasevich1-1/+1
There is no point in passing a destination address to a get_saddr() call. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28sctp: cache the ipv6 source after route lookupVlad Yasevich1-5/+10
The ipv6 routing lookup does give us a source address, but instead of filling it into the dst, it's stored in the flowi. We can use that instead of going through the entire source address selection again. Also the useless ->dst_saddr member of sctp_pf is removed. And sctp_v6_dst_saddr() is removed, instead by introduce sctp_v6_to_addr(), which can be reused to cleanup some dup code. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-27net/sctp: Use pr_fmt and pr_<level>Joe Perches1-4/+5
Change SCTP_DEBUG_PRINTK and SCTP_DEBUG_PRINTK_IPADDR to use do { print } while (0) guards. Add SCTP_DEBUG_PRINTK_CONT to fix errors in log when lines were continued. Add #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt Add a missing newline in "Failed bind hash alloc" Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-17Merge branch 'master' of ↵David S. Miller1-0/+4
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: include/linux/if_link.h
2010-05-16sctp: delete active ICMP proto unreachable timer when free transportWei Yongjun1-0/+4
transport may be free before ICMP proto unreachable timer expire, so we should delete active ICMP proto unreachable timer when transport is going away. Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-12Merge branch 'master' of ↵David S. Miller1-0/+2
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/net/wireless/ath/ar9170/usb.c drivers/scsi/iscsi_tcp.c net/ipv4/ipmr.c
2010-05-06sctp: Fix a race between ICMP protocol unreachable and connect()Vlad Yasevich1-0/+2
ICMP protocol unreachable handling completely disregarded the fact that the user may have locked the socket. It proceeded to destroy the association, even though the user may have held the lock and had a ref on the association. This resulted in the following: Attempt to release alive inet socket f6afcc00 ========================= [ BUG: held lock freed! ] ------------------------- somenu/2672 is freeing memory f6afcc00-f6afcfff, with a lock still held there! (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c 1 lock held by somenu/2672: #0: (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c stack backtrace: Pid: 2672, comm: somenu Not tainted 2.6.32-telco #55 Call Trace: [<c1232266>] ? printk+0xf/0x11 [<c1038553>] debug_check_no_locks_freed+0xce/0xff [<c10620b4>] kmem_cache_free+0x21/0x66 [<c1185f25>] __sk_free+0x9d/0xab [<c1185f9c>] sk_free+0x1c/0x1e [<c1216e38>] sctp_association_put+0x32/0x89 [<c1220865>] __sctp_connect+0x36d/0x3f4 [<c122098a>] ? sctp_connect+0x13/0x4c [<c102d073>] ? autoremove_wake_function+0x0/0x33 [<c12209a8>] sctp_connect+0x31/0x4c [<c11d1e80>] inet_dgram_connect+0x4b/0x55 [<c11834fa>] sys_connect+0x54/0x71 [<c103a3a2>] ? lock_release_non_nested+0x88/0x239 [<c1054026>] ? might_fault+0x42/0x7c [<c1054026>] ? might_fault+0x42/0x7c [<c11847ab>] sys_socketcall+0x6d/0x178 [<c10da994>] ? trace_hardirqs_on_thunk+0xc/0x10 [<c1002959>] syscall_call+0x7/0xb This was because the sctp_wait_for_connect() would aqcure the socket lock and then proceed to release the last reference count on the association, thus cause the fully destruction path to finish freeing the socket. The simplest solution is to start a very short timer in case the socket is owned by user. When the timer expires, we can do some verification and be able to do the release properly. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-01sctp: fast recovery algorithm is per association.Vlad Yasevich1-15/+17
SCTP fast recovery algorithm really applies per association and impacts all transports. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2010-05-01sctp: update transport initializationsVlad Yasevich1-25/+0
Right now, sctp transports are not fully initialized and when adding any new fields, they have to be explicitely initialized. This is prone to mistakes. So we switch to calling kzalloc() which makes things much simpler. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2010-05-01sctp: Do not force T3 timer on fast retransmissions.Vlad Yasevich1-2/+2
We don't need to force the T3 timer any more and it's actually wrong to do as it causes too long of a delay. The timer will be started if one is not running, but if one is running, we leave it alone. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-11-29Merge branch 'master' of ↵David S. Miller1-3/+2
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/ieee802154/fakehard.c drivers/net/e1000e/ich8lan.c drivers/net/e1000e/phy.c drivers/net/netxen/netxen_nic_init.c drivers/net/wireless/ath/ath9k/main.c