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path: root/include/net/inet_timewait_sock.h
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2011-12-14inet: remove rcu protection on tw_netEric Dumazet
commit b099ce2602d806 (net: Batch inet_twsk_purge) added rcu protection on tw_net for no obvious reason. struct net are refcounted anyway since timewait sockets escape from rcu protected sections. tw_net stay valid for the whole timwait lifetime. This also removes a lot of sparse errors. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-06Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
2011-10-31net: inet_timewait_sock doesnt need <linux/module.h>Paul Gortmaker
There is nothing module specific in this header, and removing it doesn't seem to uncover any implicit dependencies either. Must be simply a vestige of an ancient legacy. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-27ipv6: tcp: fix TCLASS value in ACK messages sent from TIME_WAITEric Dumazet
commit 66b13d99d96a (ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAIT) fixed IPv4 only. This part is for the IPv6 side, adding a tclass param to ip6_xmit() We alias tw_tclass and tw_tos, if socket family is INET6. [ if sockets is ipv4-mapped, only IP_TOS socket option is used to fill TOS field, TCLASS is not taken into account ] Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAITEric Dumazet
There is a long standing bug in linux tcp stack, about ACK messages sent on behalf of TIME_WAIT sockets. In the IP header of the ACK message, we choose to reflect TOS field of incoming message, and this might break some setups. Example of things that were broken : - Routing using TOS as a selector - Firewalls - Trafic classification / shaping We now remember in timewait structure the inet tos field and use it in ACK generation, and route lookup. Notes : - We still reflect incoming TOS in RST messages. - We could extend MuraliRaja Muniraju patch to report TOS value in netlink messages for TIME_WAIT sockets. - A patch is needed for IPv6 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-26atomic: use <linux/atomic.h>Arun Sharma
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-09net: optimize INET input path furtherEric Dumazet
Followup of commit b178bb3dfc30 (net: reorder struct sock fields) Optimize INET input path a bit further, by : 1) moving sk_refcnt close to sk_lock. This reduces number of dirtied cache lines by one on 64bit arches (and 64 bytes cache line size). 2) moving inet_daddr & inet_rcv_saddr at the beginning of sk (same cache line than hash / family / bound_dev_if / nulls_node) This reduces number of accessed cache lines in lookups by one, and dont increase size of inet and timewait socks. inet and tw sockets now share same place-holder for these fields. Before patch : offsetof(struct sock, sk_refcnt) = 0x10 offsetof(struct sock, sk_lock) = 0x40 offsetof(struct sock, sk_receive_queue) = 0x60 offsetof(struct inet_sock, inet_daddr) = 0x270 offsetof(struct inet_sock, inet_rcv_saddr) = 0x274 After patch : offsetof(struct sock, sk_refcnt) = 0x44 offsetof(struct sock, sk_lock) = 0x48 offsetof(struct sock, sk_receive_queue) = 0x68 offsetof(struct inet_sock, inet_daddr) = 0x0 offsetof(struct inet_sock, inet_rcv_saddr) = 0x4 compute_score() (udp or tcp) now use a single cache line per ignored item, instead of two. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-27net: suppress RCU lockdep false positive in twsk_net()Paul E. McKenney
Calls to twsk_net() are in some cases protected by reference counting as an alternative to RCU protection. Cases covered by reference counts include __inet_twsk_kill(), inet_twsk_free(), inet_twdr_do_twkill_work(), inet_twdr_twcal_tick(), and tcp_timewait_state_process(). RCU is used by inet_twsk_purge(). Locking is used by established_get_first() and established_get_next(). Finally, __inet_twsk_hashdance() is an initialization case. It appears to be non-trivial to locate the appropriate locks and reference counts from within twsk_net(), so used rcu_dereference_raw(). Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-08tcp: Fix a connect() race with timewait socketsEric Dumazet
When we find a timewait connection in __inet_hash_connect() and reuse it for a new connection request, we have a race window, releasing bind list lock and reacquiring it in __inet_twsk_kill() to remove timewait socket from list. Another thread might find the timewait socket we already chose, leading to list corruption and crashes. Fix is to remove timewait socket from bind list before releasing the bind lock. Note: This problem happens if sysctl_tcp_tw_reuse is set. Reported-by: kapil dakhane <kdakhane@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03tcp: connect() race with timewait reuseEric Dumazet
Its currently possible that several threads issuing a connect() find the same timewait socket and try to reuse it, leading to list corruptions. Condition for bug is that these threads bound their socket on same address/port of to-be-find timewait socket, and connected to same target. (SO_REUSEADDR needed) To fix this problem, we could unhash timewait socket while holding ehash lock, to make sure lookups/changes will be serialized. Only first thread finds the timewait socket, other ones find the established socket and return an EADDRNOTAVAIL error. This second version takes into account Evgeniy's review and makes sure inet_twsk_put() is called outside of locked sections. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03net: Batch inet_twsk_purgeEric W. Biederman
This function walks the whole hashtable so there is no point in passing it a network namespace. Instead I purge all timewait sockets from dead network namespaces that I find. If the namespace is one of the once I am trying to purge I am guaranteed no new timewait sockets can be formed so this will get them all. If the namespace is one I am not acting for it might form a few more but I will call inet_twsk_purge again and shortly to get rid of them. In any even if the network namespace is dead timewait sockets are useless. Move the calls of inet_twsk_purge into batch_exit routines so that if I am killing a bunch of namespaces at once I will just call inet_twsk_purge once and save a lot of redundant unnecessary work. My simple 4k network namespace exit test the cleanup time dropped from roughly 8.2s to 1.6s. While the time spent running inet_twsk_purge fell to about 2ms. 1ms for ipv4 and 1ms for ipv6. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-27Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/sh_eth.c
2009-10-20net: Fix struct inet_timewait_sock bitfield annotationEric Dumazet
commit 9e337b0f (net: annotate inet_timewait_sock bitfields) added 4/8 bytes in struct inet_timewait_sock. Fix this by declaring tw_ipv6_offset in the 'flags' bitfield The 14 bits hole is named tw_pad to make it cleary apparent. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-18inet: rename some inet_sock fieldsEric Dumazet
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>
2009-06-15net: annotate inet_timewait_sock bitfieldsVegard Nossum
The use of bitfields here would lead to false positive warnings with kmemcheck. Silence them. (Additionally, one erroneous comment related to the bitfield was also fixed.) Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2008-11-16net: Convert TCP & DCCP hash tables to use RCU / hlist_nullsEric Dumazet
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>
2008-10-01ipv4: Implement IP_TRANSPARENT socket optionKOVACS Krisztian
This patch introduces the IP_TRANSPARENT socket option: enabling that will make the IPv4 routing omit the non-local source address check on output. Setting IP_TRANSPARENT requires NET_ADMIN capability. Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-08netns : fix kernel panic in timewait socket destructionDaniel Lezcano
How to reproduce ? - create a network namespace - use tcp protocol and get timewait socket - exit the network namespace - after a moment (when the timewait socket is destroyed), the kernel panics. # BUG: unable to handle kernel NULL pointer dereference at 0000000000000007 IP: [<ffffffff821e394d>] inet_twdr_do_twkill_work+0x6e/0xb8 PGD 119985067 PUD 11c5c0067 PMD 0 Oops: 0000 [1] SMP CPU 1 Modules linked in: ipv6 button battery ac loop dm_mod tg3 libphy ext3 jbd edd fan thermal processor thermal_sys sg sata_svw libata dock serverworks sd_mod scsi_mod ide_disk ide_core [last unloaded: freq_table] Pid: 0, comm: swapper Not tainted 2.6.27-rc2 #3 RIP: 0010:[<ffffffff821e394d>] [<ffffffff821e394d>] inet_twdr_do_twkill_work+0x6e/0xb8 RSP: 0018:ffff88011ff7fed0 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffffffff82339420 RCX: ffff88011ff7ff30 RDX: 0000000000000001 RSI: ffff88011a4d03c0 RDI: ffff88011ac2fc00 RBP: ffffffff823392e0 R08: 0000000000000000 R09: ffff88002802a200 R10: ffff8800a5c4b000 R11: ffffffff823e4080 R12: ffff88011ac2fc00 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000041cbd940(0000) GS:ffff8800bff839c0(0000) knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b CR2: 0000000000000007 CR3: 00000000bd87c000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper (pid: 0, threadinfo ffff8800bff9e000, task ffff88011ff76690) Stack: ffffffff823392e0 0000000000000100 ffffffff821e3a3a 0000000000000008 0000000000000000 ffffffff821e3a61 ffff8800bff7c000 ffffffff8203c7e7 ffff88011ff7ff10 ffff88011ff7ff10 0000000000000021 ffffffff82351108 Call Trace: <IRQ> [<ffffffff821e3a3a>] ? inet_twdr_hangman+0x0/0x9e [<ffffffff821e3a61>] ? inet_twdr_hangman+0x27/0x9e [<ffffffff8203c7e7>] ? run_timer_softirq+0x12c/0x193 [<ffffffff820390d1>] ? __do_softirq+0x5e/0xcd [<ffffffff8200d08c>] ? call_softirq+0x1c/0x28 [<ffffffff8200e611>] ? do_softirq+0x2c/0x68 [<ffffffff8201a055>] ? smp_apic_timer_interrupt+0x8e/0xa9 [<ffffffff8200cad6>] ? apic_timer_interrupt+0x66/0x70 <EOI> [<ffffffff82011f4c>] ? default_idle+0x27/0x3b [<ffffffff8200abbd>] ? cpu_idle+0x5f/0x7d Code: e8 01 00 00 4c 89 e7 41 ff c5 e8 8d fd ff ff 49 8b 44 24 38 4c 89 e7 65 8b 14 25 24 00 00 00 89 d2 48 8b 80 e8 00 00 00 48 f7 d0 <48> 8b 04 d0 48 ff 40 58 e8 fc fc ff ff 48 89 df e8 c0 5f 04 00 RIP [<ffffffff821e394d>] inet_twdr_do_twkill_work+0x6e/0xb8 RSP <ffff88011ff7fed0> CR2: 0000000000000007 This patch provides a function to purge all timewait sockets related to a network namespace. The timewait sockets life cycle is not tied with the network namespace, that means the timewait sockets stay alive while the network namespace dies. The timewait sockets are for avoiding to receive a duplicate packet from the network, if the network namespace is freed, the network stack is removed, so no chance to receive any packets from the outside world. Furthermore, having a pending destruction timer on these sockets with a network namespace freed is not safe and will lead to an oops if the timer callback which try to access data belonging to the namespace like for example in: inet_twdr_do_twkill_work -> NET_INC_STATS_BH(twsk_net(tw), LINUX_MIB_TIMEWAITED); Purging the timewait sockets at the network namespace destruction will: 1) speed up memory freeing for the namespace 2) fix kernel panic on asynchronous timewait destruction Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: Denis V. Lunev <den@openvz.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[NETNS]: Compilation warnings under CONFIG_NET_NS.Denis V. Lunev
Recent commits from YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> have been introduced a several compilation warnings 'assignment discards qualifiers from pointer target type' due to extra const modifier in the inline call parameters of {dev|sock|twsk}_net_set. Drop it. Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.YOSHIFUJI Hideaki
Introduce per-sock inlines: sock_net(), sock_net_set() and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set(). Without CONFIG_NET_NS, no namespace other than &init_net exists. Let's explicitly define them to help compiler optimizations. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-02-03[INET_TIMEWAIT_SOCK]: Reorganize struct inet_timewait_sock to save some bytesArnaldo Carvalho de Melo
/home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c: struct inet_timewait_sock | -8 struct tcp_timewait_sock | -8 2 structs changed tcp_v6_rcv | -6 1 function changed, 6 bytes removed, diff: -6 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[INET]: Uninline the inet_twsk_put function.Pavel Emelyanov
This one is not that big, but is widely used: saves 1200 bytes from net/ipv4/built-in.o add/remove: 1/0 grow/shrink: 1/12 up/down: 97/-1300 (-1203) function old new delta inet_twsk_put - 87 +87 __inet_lookup_listener 274 284 +10 tcp_sacktag_write_queue 2255 2254 -1 tcp_time_wait 482 411 -71 __inet_check_established 796 722 -74 tcp_v4_err 973 898 -75 __inet_twsk_kill 230 154 -76 inet_twsk_deschedule 180 103 -77 tcp_v4_do_rcv 462 384 -78 inet_hash_connect 686 607 -79 inet_twdr_do_twkill_work 236 150 -86 inet_twdr_twcal_tick 395 307 -88 tcp_v4_rcv 1744 1480 -264 tcp_timewait_state_process 975 644 -331 Export it for ipv6 module. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Add a network namespace parameter to struct sockEric W. Biederman
Sockets need to get a reference to their network namespace, or possibly a simple hold if someone registers on the network namespace notifier and will free the sockets when the namespace is going to be destroyed. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14[INET_SOCK]: make net/ipv4/inet_timewait_sock.c:__inet_twsk_kill() staticAdrian Bunk
This patch makes the needlessly global __inet_twsk_kill() static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-05[INET]: twcal_jiffie should be unsigned long, not intEric Dumazet
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-11-22WorkStruct: Pass the work_struct pointer instead of context dataDavid Howells
Pass the work_struct pointer to the work function rather than context data. The work function can use container_of() to work out the data. For the cases where the container of the work_struct may go away the moment the pending bit is cleared, it is made possible to defer the release of the structure by deferring the clearing of the pending bit. To make this work, an extra flag is introduced into the management side of the work_struct. This governs auto-release of the structure upon execution. Ordinarily, the work queue executor would release the work_struct for further scheduling or deallocation by clearing the pending bit prior to jumping to the work function. This means that, unless the driver makes some guarantee itself that the work_struct won't go away, the work function may not access anything else in the work_struct or its container lest they be deallocated.. This is a problem if the auxiliary data is taken away (as done by the last patch). However, if the pending bit is *not* cleared before jumping to the work function, then the work function *may* access the work_struct and its container with no problems. But then the work function must itself release the work_struct by calling work_release(). In most cases, automatic release is fine, so this is the default. Special initiators exist for the non-auto-release case (ending in _NAR). Signed-Off-By: David Howells <dhowells@redhat.com>
2006-10-12[NET]: Introduce protocol-specific destructor for time-wait sockets.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28[IPV4]: inet_rcv_saddr() annotationsAl Viro
inet_rcv_saddr() returns net-endian Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28[IPV4]: struct inet_timewait_sock annotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-04-29[NET]: use hlist_unhashed()Akinobu Mita
Use hlist_unhashed() rather than accessing inside data structure. Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-26Don't include linux/config.h from anywhere else in include/David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-01-03[INET_SOCK]: Move struct inet_sock & helper functions to net/inet_sock.hArnaldo Carvalho de Melo
To help in reducing the number of include dependencies, several files were touched as they were getting needed headers indirectly for stuff they use. Thanks also to Alan Menegotto for pointing out that net/dccp/proto.c had linux/dccp.h include twice. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TWSK]: Introduce struct timewait_sock_opsArnaldo Carvalho de Melo
So that we can share several timewait sockets related functions and make the timewait mini sockets infrastructure closer to the request mini sockets one. Next changesets will take advantage of this, moving more code out of TCP and DCCP v4 and v6 to common infrastructure. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[IPV6]: Introduce inet6_timewait_sockArnaldo Carvalho de Melo
Out of tcp6_timewait_sock, that now is just an aggregation of inet_timewait_sock and inet6_timewait_sock, using tw_ipv6_offset in struct inet_timewait_sock, that is common to the IPv6 transport protocols that use timewait sockets, like DCCP and TCP. tw_ipv6_offset plays the struct inet_sock pinfo6 role, i.e. for the generic code to find the IPv6 area in a timewait sock. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-10[TWSK]: Grab the module refcount for timewait socketsArnaldo Carvalho de Melo
This is required to avoid unloading a module that has active timewait sockets, such as DCCP. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-03[INET]: speedup inet (tcp/dccp) lookupsEric Dumazet
Arnaldo and I agreed it could be applied now, because I have other pending patches depending on this one (Thank you Arnaldo) (The other important patch moves skc_refcnt in a separate cache line, so that the SMP/NUMA performance doesnt suffer from cache line ping pongs) 1) First some performance data : -------------------------------- tcp_v4_rcv() wastes a *lot* of time in __inet_lookup_established() The most time critical code is : sk_for_each(sk, node, &head->chain) { if (INET_MATCH(sk, acookie, saddr, daddr, ports, dif)) goto hit; /* You sunk my battleship! */ } The sk_for_each() does use prefetch() hints but only the begining of "struct sock" is prefetched. As INET_MATCH first comparison uses inet_sk(__sk)->daddr, wich is far away from the begining of "struct sock", it has to bring into CPU cache cold cache line. Each iteration has to use at least 2 cache lines. This can be problematic if some chains are very long. 2) The goal ----------- The idea I had is to change things so that INET_MATCH() may return FALSE in 99% of cases only using the data already in the CPU cache, using one cache line per iteration. 3) Description of the patch --------------------------- Adds a new 'unsigned int skc_hash' field in 'struct sock_common', filling a 32 bits hole on 64 bits platform. struct sock_common { unsigned short skc_family; volatile unsigned char skc_state; unsigned char skc_reuse; int skc_bound_dev_if; struct hlist_node skc_node; struct hlist_node skc_bind_node; atomic_t skc_refcnt; + unsigned int skc_hash; struct proto *skc_prot; }; Store in this 32 bits field the full hash, not masked by (ehash_size - 1) Using this full hash as the first comparison done in INET_MATCH permits us immediatly skip the element without touching a second cache line in case of a miss. Suppress the sk_hashent/tw_hashent fields since skc_hash (aliased to sk_hash and tw_hash) already contains the slot number if we mask with (ehash_size - 1) File include/net/inet_hashtables.h 64 bits platforms : #define INET_MATCH(__sk, __hash, __cookie, __saddr, __daddr, __ports, __dif)\ (((__sk)->sk_hash == (__hash)) ((*((__u64 *)&(inet_sk(__sk)->daddr)))== (__cookie)) && \ ((*((__u32 *)&(inet_sk(__sk)->dport))) == (__ports)) && \ (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif)))) 32bits platforms: #define TCP_IPV4_MATCH(__sk, __hash, __cookie, __saddr, __daddr, __ports, __dif)\ (((__sk)->sk_hash == (__hash)) && \ (inet_sk(__sk)->daddr == (__saddr)) && \ (inet_sk(__sk)->rcv_saddr == (__daddr)) && \ (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif)))) - Adds a prefetch(head->chain.first) in __inet_lookup_established()/__tcp_v4_check_established() and __inet6_lookup_established()/__tcp_v6_check_established() and __dccp_v4_check_established() to bring into cache the first element of the list, before the {read|write}_lock(&head->lock); Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[TIMEWAIT]: Move inet_timewait_death_row routines to ↵Arnaldo Carvalho de Melo
net/ipv4/inet_timewait_sock.c Also export the ones that will be used in the next changeset, when DCCP uses this infrastructure. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[TIMEWAIT]: Introduce inet_timewait_death_rowArnaldo Carvalho de Melo
That groups all of the tables and variables associated to the TCP timewait schedulling/recycling/killing code, that now can be isolated from the TCP specific code and used by other transport protocols, such as DCCP. Next changeset will move this code to net/ipv4/inet_timewait_sock.c Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET_TWSK]: Introduce inet_twsk_allocArnaldo Carvalho de Melo
With the parts of tcp_time_wait that are not TCP specific, tcp_time_wait uses it and so will dccp_time_wait. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Generalise the TCP sock ID lookup routinesArnaldo Carvalho de Melo
And also some TIME_WAIT functions. [acme@toy net-2.6.14]$ grep built-in /tmp/before.size /tmp/after.size /tmp/before.size: 282955 13122 9312 305389 4a8ed net/ipv4/built-in.o /tmp/after.size: 281566 13122 9312 304000 4a380 net/ipv4/built-in.o [acme@toy net-2.6.14]$ I kept them still inlined, will uninline at some point to see what would be the performance difference. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Generalise tcp_tw_bucket, aka TIME_WAIT socketsArnaldo Carvalho de Melo
This paves the way to generalise the rest of the sock ID lookup routines and saves some bytes in TCPv4 TIME_WAIT sockets on distro kernels (where IPv6 is always built as a module): [root@qemu ~]# grep tw_sock /proc/slabinfo tw_sock_TCPv6 0 0 128 31 1 tw_sock_TCP 0 0 96 41 1 [root@qemu ~]# Now if a protocol wants to use the TIME_WAIT generic infrastructure it only has to set the sk_prot->twsk_obj_size field with the size of its inet_timewait_sock derived sock and proto_register will create sk_prot->twsk_slab, for now its only for INET sockets, but we can introduce timewait_sock later if some non INET transport protocolo wants to use this stuff. Next changesets will take advantage of this new infrastructure to generalise even more TCP code. [acme@toy net-2.6.14]$ grep built-in /tmp/before.size /tmp/after.size /tmp/before.size: 188646 11764 5068 205478 322a6 net/ipv4/built-in.o /tmp/after.size: 188144 11764 5068 204976 320b0 net/ipv4/built-in.o [acme@toy net-2.6.14]$ Tested with both IPv4 & IPv6 (::1 (localhost) & ::ffff:172.20.0.1 (qemu host)). Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>