aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv4/tcp.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2009-11-17Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-7/+12
Conflicts: drivers/net/can/Kconfig
2009-11-13tcp: provide more information on the tcp receive_queue bugsIlpo Järvinen1-7/+12
The addition of rcv_nxt allows to discern whether the skb was out of place or tp->copied. Also catch fancy combination of flags if necessary (sadly we might miss the actual causer flags as it might have already returned). Btw, we perhaps would want to forward copied_seq in somewhere or otherwise we might have some nice loop with WARN stuff within but where to do that safely I don't know at this stage until more is known (but it is not made significantly worse by this patch). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-27Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-13/+46
Conflicts: drivers/net/sh_eth.c
2009-10-22net: use WARN() for the WARN_ON in commit b6b39e8f3fbbbArjan van de Ven1-3/+3
Commit b6b39e8f3fbbb (tcp: Try to catch MSG_PEEK bug) added a printk() to the WARN_ON() that's in tcp.c. This patch changes this combination to WARN(); the advantage of WARN() is that the printk message shows up inside the message, so that kerneloops.org will collect the message. In addition, this gets rid of an extra if() statement. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-20tcp: Try to catch MSG_PEEK bugHerbert Xu1-1/+3
This patch tries to print out more information when we hit the MSG_PEEK bug in tcp_recvmsg. It's been around since at least 2005 and it's about time that we finally fix it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-19tcp: fix TCP_DEFER_ACCEPT retrans calculationJulian Anastasov1-12/+43
Fix TCP_DEFER_ACCEPT conversion between seconds and retransmission to match the TCP SYN-ACK retransmission periods because the time is converted to such retransmissions. The old algorithm selects one more retransmission in some cases. Allow up to 255 retransmissions. Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-18inet: rename some inet_sock fieldsEric Dumazet1-2/+2
In order to have better cache layouts of struct sock (separate zones for rx/tx paths), we need this preliminary patch. Goal is to transfert fields used at lookup time in the first read-mostly cache line (inside struct sock_common) and move sk_refcnt to a separate cache line (only written by rx path) This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr, sport and id fields. This allows a future patch to define these fields as macros, like sk_refcnt, without name clashes. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-13tcp: replace ehash_size by ehash_maskEric Dumazet1-6/+5
Storing the mask (size - 1) instead of the size allows fast path to be a bit faster. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-02net: splice() from tcp to pipe should take into account O_NONBLOCKEric Dumazet1-1/+1
tcp_splice_read() doesnt take into account socket's O_NONBLOCK flag Before this patch : splice(socket,0,pipe,0,128*1024,SPLICE_F_MOVE); causes a random endless block (if pipe is full) and splice(socket,0,pipe,0,128*1024,SPLICE_F_MOVE | SPLICE_F_NONBLOCK); will return 0 immediately if the TCP buffer is empty. User application has no way to instruct splice() that socket should be in blocking mode but pipe in nonblock more. Many projects cannot use splice(tcp -> pipe) because of this flaw. http://git.samba.org/?p=samba.git;a=history;f=source3/lib/recvfile.c;h=ea0159642137390a0f7e57a123684e6e63e47581;hb=HEAD http://lkml.indiana.edu/hypermail/linux/kernel/0807.2/0687.html Linus introduced SPLICE_F_NONBLOCK in commit 29e350944fdc2dfca102500790d8ad6d6ff4f69d (splice: add SPLICE_F_NONBLOCK flag ) It doesn't make the splice itself necessarily nonblocking (because the actual file descriptors that are spliced from/to may block unless they have the O_NONBLOCK flag set), but it makes the splice pipe operations nonblocking. Linus intention was clear : let SPLICE_F_NONBLOCK control the splice pipe mode only This patch instruct tcp_splice_read() to use the underlying file O_NONBLOCK flag, as other socket operations do. Users will then call : splice(socket,0,pipe,0,128*1024,SPLICE_F_MOVE | SPLICE_F_NONBLOCK ); to block on data coming from socket (if file is in blocking mode), and not block on pipe output (to avoid deadlock) First version of this patch was submitted by Octavian Purdila Reported-by: Volker Lendecke <vl@samba.org> Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-01net/ipv4/tcp.c: fix min() type mismatch warningAndrew Morton1-1/+1
net/ipv4/tcp.c: In function 'do_tcp_setsockopt': net/ipv4/tcp.c:2050: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-30net: Make setsockopt() optlen be unsigned.David S. Miller1-3/+3
This provides safety against negative optlen at the type level instead of depending upon (sometimes non-trivial) checks against this sprinkled all over the the place, in each and every implementation. Based upon work done by Arjan van de Ven and feedback from Linus Torvalds. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-22mm: replace various uses of num_physpages by totalram_pagesJan Beulich1-2/+2
Sizing of memory allocations shouldn't depend on the number of physical pages found in a system, as that generally includes (perhaps a huge amount of) non-RAM pages. The amount of what actually is usable as storage should instead be used as a basis here. Some of the calculations (i.e. those not intending to use high memory) should likely even use (totalram_pages - totalhigh_pages). Signed-off-by: Jan Beulich <jbeulich@novell.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Dave Airlie <airlied@linux.ie> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: "David S. Miller" <davem@davemloft.net> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-15tcp: fix ssthresh u16 leftoverIlpo Järvinen1-1/+1
It was once upon time so that snd_sthresh was a 16-bit quantity. ...That has not been true for long period of time. I run across some ancient compares which still seem to trust such legacy. Put all that magic into a single place, I hopefully found all of them. Compile tested, though linking of allyesconfig is ridiculous nowadays it seems. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-02tcp: replace hard coded GFP_KERNEL with sk_allocationWu Fengguang1-5/+5
This fixed a lockdep warning which appeared when doing stress memory tests over NFS: inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. page reclaim => nfs_writepage => tcp_sendmsg => lock sk_lock mount_root => nfs_root_data => tcp_close => lock sk_lock => tcp_send_fin => alloc_skb_fclone => page reclaim David raised a concern that if the allocation fails in tcp_send_fin(), and it's GFP_ATOMIC, we are going to yield() (which sleeps) and loop endlessly waiting for the allocation to succeed. But fact is, the original GFP_KERNEL also sleeps. GFP_ATOMIC+yield() looks weird, but it is no worse the implicit sleep inside GFP_KERNEL. Both could loop endlessly under memory pressure. CC: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> CC: David S. Miller <davem@davemloft.net> CC: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-28tcp: keepalive cleanupsEric Dumazet1-3/+3
Introduce keepalive_probes(tp) helper, and use it, like keepalive_time_when(tp) and keepalive_intvl_when(tp) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-09net: adding memory barrier to the poll and receive callbacksJiri Olsa1-1/+1
Adding memory barrier after the poll_wait function, paired with receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper to wrap the memory barrier. Without the memory barrier, following race can happen. The race fires, when following code paths meet, and the tp->rcv_nxt and __add_wait_queue updates stay in CPU caches. CPU1 CPU2 sys_select receive packet ... ... __add_wait_queue update tp->rcv_nxt ... ... tp->rcv_nxt check sock_def_readable ... { schedule ... if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep) ... } If there was no cache the code would work ok, since the wait_queue and rcv_nxt are opposit to each other. Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already passed the tp->rcv_nxt check and sleeps, or will get the new value for tp->rcv_nxt and will return with new data mask. In both cases the process (CPU1) is being added to the wait queue, so the waitqueue_active (CPU2) call cannot miss and will wake up CPU1. The bad case is when the __add_wait_queue changes done by CPU1 stay in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then endup calling schedule and sleep forever if there are no more data on the socket. Calls to poll_wait in following modules were ommited: net/bluetooth/af_bluetooth.c net/irda/af_irda.c net/irda/irnet/irnet_ppp.c net/mac80211/rc80211_pid_debugfs.c net/phonet/socket.c net/rds/af_rds.c net/rfkill/core.c net/sunrpc/cache.c net/sunrpc/rpc_pipe.c net/tipc/socket.c Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-29tcp: Do not tack on TSO data to non-TSO packetHerbert Xu1-5/+10
If a socket starts out on a non-TSO route, and then switches to a TSO route, then we will tack on data to the tail of the tx queue even if it started out life as non-TSO. This is suboptimal because all of it will then be copied and checksummed unnecessarily. This patch fixes this by ensuring that skb->ip_summed is set to CHECKSUM_PARTIAL before appending extra data beyond the MSS. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-28tcp: Use SKB queue and list helpers instead of doing it by-hand.David S. Miller1-10/+7
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27tcp: Do not check flush when comparing options for GROHerbert Xu1-1/+1
There is no need to repeatedly check flush when comparing TCP options for GRO as it will be false 99% of the time where it matters. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27gro: Avoid unnecessary comparison after skb_gro_headerHerbert Xu1-6/+16
For the overwhelming majority of cases, skb_gro_header's return value cannot be NULL. Yet we must check it because of its current form. This patch splits it up into multiple functions in order to avoid this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27tcp: Optimise len/mss comparisonHerbert Xu1-1/+1
Instead of checking len > mss || len == 0, we can accomplish both by checking (len - 1) > mss using the unsigned wraparound. At nearly a million times a second, this might just help. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27tcp: Remove unnecessary window comparisons for GROHerbert Xu1-1/+1
The window has already been checked as part of the flag word so there is no need to check it explicitly. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27tcp: Optimise GRO port comparisonsHerbert Xu1-1/+1
Instead of doing two 16-bit operations for the source/destination ports, we can do one 32-bit operation to take care both. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-18tcp: fix MSG_PEEK race checkIlpo Järvinen1-1/+4
Commit 518a09ef11 (tcp: Fix recvmsg MSG_PEEK influence of blocking behavior) lets the loop run longer than the race check did previously expect, so we need to be more careful with this check and consider the work we have been doing. I tried my best to deal with urg hole madness too which happens here: if (!sock_flag(sk, SOCK_URGINLINE)) { ++*seq; ... by using additional offset by one but I certainly have very little interest in testing that part. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Tested-by: Frans Pop <elendil@planet.nl> Tested-by: Ian Zimmermann <itz@buug.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-17gro: Fix use after free in tcp_gro_receiveHerbert Xu1-2/+4
After calling skb_gro_receive skb->len can no longer be relied on since if the skb was merged using frags, then its pages will have been removed and the length reduced. This caused tcp_gro_receive to prematurely end merging which resulted in suboptimal performance with ixgbe. The fix is to store skb->len on the stack. Reported-by: Mark Wagner <mwagner@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-31ipv4: remove unused parameter from tcp_recv_urg().Rami Rosen1-3/+2
Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-18tcp: remove parameter from tcp_recv_urg().Rami Rosen1-3/+2
This patch removes an unused parameter (addr_len) from tcp_recv_urg() method in net/ipv4/tcp.c. Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-15tcp: make sure xmit goal size never becomes zeroIlpo Järvinen1-1/+1
It's not too likely to happen, would basically require crafted packets (must hit the max guard in tcp_bound_to_half_wnd()). It seems that nothing that bad would happen as there's tcp_mems and congestion window that prevent runaway at some point from hurting all too much (I'm not that sure what all those zero sized segments we would generate do though in write queue). Preventing it regardless is certainly the best way to go. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-15tcp: cache result of earlier divides when mss-aligning thingsIlpo Järvinen1-2/+12
The results is very unlikely change every so often so we hardly need to divide again after doing that once for a connection. Yet, if divide still becomes necessary we detect that and do the right thing and again settle for non-divide state. Takes the u16 space which was previously taken by the plain xmit_size_goal. This should take care part of the tso vs non-tso difference we found earlier. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-15tcp: simplify tcp_current_mssIlpo Järvinen1-8/+35
There's very little need for most of the callsites to get tp->xmit_goal_size updated. That will cost us divide as is, so slice the function in two. Also, the only users of the tp->xmit_goal_size are directly behind tcp_current_mss(), so there's no need to store that variable into tcp_sock at all! The drop of xmit_goal_size currently leaves 16-bit hole and some reorganization would again be necessary to change that (but I'm aiming to fill that hole with u16 xmit_goal_size_segs to cache the results of the remaining divide to get that tso on regression). Bring xmit_goal_size parts into tcp.c Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-02tcp: in sendmsg/pages open code the real goto targetIlpo Järvinen1-2/+2
copied was assigned zero right before the goto, so if (copied) cannot ever be true. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-08gro: Optimise TCP packet receptionHerbert Xu1-7/+8
gro: Optimise TCP packet reception As this function can be called more than half a million times for 10GbE, it's important to optimise it as much as we can. This patch uses bit ops to logical ops, as well as open coding memcmp to exploit alignment properties. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-30Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-1/+2
Conflicts: drivers/net/e1000/e1000_main.c
2009-01-29gro: Avoid copying headers of unmerged packetsHerbert Xu1-8/+8
Unfortunately simplicity isn't always the best. The fraginfo interface turned out to be suboptimal. The problem was quite obvious. For every packet, we have to copy the headers from the frags structure into skb->head, even though for 99% of the packets this part is immediately thrown away after the merge. LRO didn't have this problem because it directly read the headers from the frags structure. This patch attempts to address this by creating an interface that allows GRO to access the headers in the first frag without having to copy it. Because all drivers that use frags place the headers in the first frag this optimisation should be enough. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-26tcp: Fix length tcp_splice_data_recv passes to skb_splice_bits.Dimitris Michailidis1-1/+2
tcp_splice_data_recv has two lengths to consider: the len parameter it gets from tcp_read_sock, which specifies the amount of data in the skb, and rd_desc->count, which is the amount of data the splice caller still wants. Currently it passes just the latter to skb_splice_bits, which then splices min(rd_desc->count, skb->len - offset) bytes. Most of the time this is fine, except when the skb contains urgent data. In that case len goes only up to the urgent byte and is less than skb->len - offset. By ignoring len tcp_splice_data_recv may a) splice data tcp_read_sock told it not to, b) return to tcp_read_sock a value > len. Now, tcp_read_sock doesn't handle used > len and leaves the socket in a bad state (both sk_receive_queue and copied_seq are bad at that point) resulting in duplicated data and corruption. Fix by passing min(rd_desc->count, len) to skb_splice_bits. Signed-off-by: Dimitris Michailidis <dm@chelsio.com> Acked-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-14gso: Ensure that the packet is long enoughHerbert Xu1-6/+7
When we get a GSO packet from an untrusted source, we need to ensure that it is sufficiently long so that we don't end up crashing. Based on discovery and patch by Ian Campbell. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-13tcp: splice as many packets as possible at onceWilly Tarreau1-2/+9
As spotted by Willy Tarreau, current splice() from tcp socket to pipe is not optimal. It processes at most one segment per call. This results in low performance and very high overhead due to syscall rate when splicing from interfaces which do not support LRO. Willy provided a patch inside tcp_splice_read(), but a better fix is to let tcp_read_sock() process as many segments as possible, so that tcp_rcv_space_adjust() and tcp_cleanup_rbuf() are called less often. With this change, splice() behaves like tcp_recvmsg(), being able to consume many skbs in one system call. With typical 1460 bytes of payload per frame, that means splice(SPLICE_F_NONBLOCK) can return 16*1460 = 23360 bytes. Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-09Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_txLinus Torvalds1-3/+2
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (22 commits) ioat: fix self test for multi-channel case dmaengine: bump initcall level to arch_initcall dmaengine: advertise all channels on a device to dma_filter_fn dmaengine: use idr for registering dma device numbers dmaengine: add a release for dma class devices and dependent infrastructure ioat: do not perform removal actions at shutdown iop-adma: enable module removal iop-adma: kill debug BUG_ON iop-adma: let devm do its job, don't duplicate free dmaengine: kill enum dma_state_client dmaengine: remove 'bigref' infrastructure dmaengine: kill struct dma_client and supporting infrastructure dmaengine: replace dma_async_client_register with dmaengine_get atmel-mci: convert to dma_request_channel and down-level dma_slave dmatest: convert to dma_request_channel dmaengine: introduce dma_request_channel and private channels net_dma: convert to dma_find_channel dmaengine: provide a common 'issue_pending_all' implementation dmaengine: centralize channel allocation, introduce dma_find_channel dmaengine: up-level reference counting to the module level ...
2009-01-08tcp6: Add GRO supportHerbert Xu1-0/+2
This patch adds GRO support for TCP over IPv6. The code is exactly the same as the IPv4 version except for the pseudo-header checksum computation. Note that I've removed the unused tcphdr argument from tcp_v6_check rather than invent a bogus value for GRO. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-06net_dma: convert to dma_find_channelDan Williams1-2/+2
Use the general-purpose channel allocation provided by dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: up-level reference counting to the module levelDan Williams1-1/+0
Simply, if a client wants any dmaengine channel then prevent all dmaengine modules from being removed. Once the clients are done re-enable module removal. Why?, beyond reducing complication: 1/ Tracking reference counts per-transaction in an efficient manner, as is currently done, requires a complicated scheme to avoid cache-line bouncing effects. 2/ Per-transaction ref-counting gives the false impression that a dma-driver can be gracefully removed ahead of its user (net, md, or dma-slave) 3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but if such an engine were built one day we still would not need to notify clients of remove events. The driver can simply return NULL to a ->prep() request, something that is much easier for a client to handle. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-05tcp: Kill extraneous SPLICE_F_NONBLOCK checks.David S. Miller1-4/+0
In splice TCP receive, the SPLICE_F_NONBLOCK flag is used to compute the "timeo" value. So checking it again inside of the main receive loop to trigger -EAGAIN processing is entirely unnecessary. Noticed by Jarek P. and Lennert Buytenhek. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-05tcp: don't mask EOF and socket errors on nonblocking splice receiveLennert Buytenhek1-4/+4
Currently, setting SPLICE_F_NONBLOCK on splice from a TCP socket results in masking of EOF (RDHUP) and error conditions on the socket by an -EAGAIN return. Move the NONBLOCK check in tcp_splice_read() to be after the EOF and error checks to fix this. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-04gro: Use gso_size to store MSSHerbert Xu1-4/+1
In order to allow GRO packets without frag_list at all, we need to store the MSS in the packet itself. The obvious place is gso_size. The only thing to watch out for is if the packet ends up not being GRO then we need to clear gso_size before pushing the packet into the stack. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-29net: Fix percpu counters deadlockHerbert Xu1-1/+2
When we converted the protocol atomic counters such as the orphan count and the total socket count deadlocks were introduced due to the mismatch in BH status of the spots that used the percpu counter operations. Based on the diagnosis and patch by Peter Zijlstra, this patch fixes these issues by disabling BH where we may be in process context. Reported-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Tested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15tcp: Add GRO supportHerbert Xu1-0/+100
This patch adds the TCP-specific portion of GRO. The criterion for merging is extremely strict (the TCP header must match exactly apart from the checksum) so as to allow refragmentation. Otherwise this is pretty much identical to LRO, except that we support the merging of ECN packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25net: Use a percpu_counter for orphan_countEric Dumazet1-5/+7
Instead of using one atomic_t per protocol, use a percpu_counter for "orphan_count", to reduce cache line contention on heavy duty network servers. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25net: Use a percpu_counter for sockets_allocatedEric Dumazet1-2/+6
Instead of using one atomic_t per protocol, use a percpu_counter for "sockets_allocated", to reduce cache line contention on heavy duty network servers. Note : We revert commit (248969ae31e1b3276fc4399d67ce29a5d81e6fd9 net: af_unix can make unix_nr_socks visbile in /proc), since it is not anymore used after sock_prot_inuse_add() addition Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16net: Convert TCP & DCCP hash tables to use RCU / hlist_nullsEric Dumazet1-2/+2
RCU was added to UDP lookups, using a fast infrastructure : - sockets kmem_cache use SLAB_DESTROY_BY_RCU and dont pay the price of call_rcu() at freeing time. - hlist_nulls permits to use few memory barriers. This patch uses same infrastructure for TCP/DCCP established and timewait sockets. Thanks to SLAB_DESTROY_BY_RCU, no slowdown for applications using short lived TCP connections. A followup patch, converting rwlocks to spinlocks will even speedup this case. __inet_lookup_established() is pretty fast now we dont have to dirty a contended cache line (read_lock/read_unlock) Only established and timewait hashtable are converted to RCU (bind table and listen table are still using traditional locking) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-06Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-2/+1
Conflicts: drivers/net/wireless/ath5k/base.c net/8021q/vlan_core.c