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2015-10-23tcp/dccp: fix hashdance race for passive sessionsEric Dumazet1-2/+2
Multiple cpus can process duplicates of incoming ACK messages matching a SYN_RECV request socket. This is a rare event under normal operations, but definitely can happen. Only one must win the race, otherwise corruption would occur. To fix this without adding new atomic ops, we use logic in inet_ehash_nolisten() to detect the request was present in the same ehash bucket where we try to insert the new child. If request socket was not found, we have to undo the child creation. This actually removes a spin_lock()/spin_unlock() pair in reqsk_queue_unlink() for the fast path. Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03tcp/dccp: install syn_recv requests into ehash tableEric Dumazet1-0/+1
In this patch, we insert request sockets into TCP/DCCP regular ehash table (where ESTABLISHED and TIMEWAIT sockets are) instead of using the per listener hash table. ACK packets find SYN_RECV pseudo sockets without having to find and lock the listener. In nominal conditions, this halves pressure on listener lock. Note that this will allow for SO_REUSEPORT refinements, so that we can select a listener using cpu/numa affinities instead of the prior 'consistent hash', since only SYN packets will apply this selection logic. We will shrink listen_sock in the following patch to ease code review. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ying Cai <ycai@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29inet: constify __inet_inherit_port() sock argumentEric Dumazet1-1/+1
socket is not touched, make it const. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09inet: simplify timewait refcountingEric Dumazet1-2/+2
timewait sockets have a complex refcounting logic. Once we realize it should be similar to established and syn_recv sockets, we can use sk_nulls_del_node_init_rcu() and remove inet_twsk_unhash() In particular, deferred inet_twsk_put() added in commit 13475a30b66cd ("tcp: connect() race with timewait reuse") looks unecessary : When removing a timewait socket from ehash or bhash, caller must own a reference on the socket anyway. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-26tcp: fix/cleanup inet_ehash_locks_alloc()Eric Dumazet1-44/+3
If tcp ehash table is constrained to a very small number of buckets (eg boot parameter thash_entries=128), then we can crash if spinlock array has more entries. While we are at it, un-inline inet_ehash_locks_alloc() and make following changes : - Budget 2 cache lines per cpu worth of 'spinlocks' - Try to kmalloc() the array to avoid extra TLB pressure. (Most servers at Google allocate 8192 bytes for this hash table) - Get rid of various #ifdef Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21inet_hashinfo: remove bsocket counterEric Dumazet1-2/+0
We no longer need bsocket atomic counter, as inet_csk_get_port() calls bind_conflict() regardless of its value, after commit 2b05ad33e1e624e ("tcp: bind() fix autoselection to share ports") This patch removes overhead of maintaining this counter and double inet_csk_get_port() calls under pressure. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Marcelo Ricardo Leitner <mleitner@redhat.com> Cc: Flavio Leitner <fbl@redhat.com> Acked-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18inet: get rid of last __inet_hash_connect() argumentEric Dumazet1-3/+1
We now always call __inet_hash_nolisten(), no need to pass it as an argument. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18ipv6: get rid of __inet6_hash()Eric Dumazet1-0/+1
We can now use inet_hash() and __inet_hash() instead of private functions. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18inet: add IPv6 support to sk_ehashfn()Eric Dumazet1-0/+19
Intent is to converge IPv4 & IPv6 inet_hash functions to factorize code. IPv4 sockets initialize sk_rcv_saddr and sk_v6_daddr in this patch, thanks to new sk_daddr_set() and sk_rcv_saddr_set() helpers. __inet6_hash can now use sk_ehashfn() instead of a private inet6_sk_ehashfn() and will simply use __inet_hash() in a following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18net: introduce sk_ehashfn() helperEric Dumazet1-0/+2
Goal is to unify IPv4/IPv6 inet_hash handling, and use common helpers for all kind of sockets (full sockets, timewait and request sockets) inet_sk_ehashfn() becomes sk_ehashfn() but still only copes with IPv4 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18netns: constify net_hash_mix() and various callersEric Dumazet1-3/+3
const qualifiers ease code review by making clear which objects are not written in a function. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-12net: Introduce possible_net_tEric W. Biederman1-3/+1
Having to say > #ifdef CONFIG_NET_NS > struct net *net; > #endif in structures is a little bit wordy and a little bit error prone. Instead it is possible to say: > typedef struct { > #ifdef CONFIG_NET_NS > struct net *net; > #endif > } possible_net_t; And then in a header say: > possible_net_t net; Which is cleaner and easier to use and easier to test, as the possible_net_t is always there no matter what the compile options. Further this allows read_pnet and write_pnet to be functions in all cases which is better at catching typos. This change adds possible_net_t, updates the definitions of read_pnet and write_pnet, updates optional struct net * variables that write_pnet uses on to have the type possible_net_t, and finally fixes up the b0rked users of read_pnet and write_pnet. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14net: Use a more standard macro for INET_ADDR_COOKIEJoe Perches1-3/+5
Missing a colon on definition use is a bit odd so change the macro for the 32 bit case to declare an __attribute__((unused)) and __deprecated variable. The __deprecated attribute will cause gcc to emit an error if the variable is actually used. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-08tcp/dccp: remove twchainEric Dumazet1-7/+2
TCP listener refactoring, part 3 : Our goal is to hash SYN_RECV sockets into main ehash for fast lookup, and parallel SYN processing. Current inet_ehash_bucket contains two chains, one for ESTABLISH (and friend states) sockets, another for TIME_WAIT sockets only. As the hash table is sized to get at most one socket per bucket, it makes little sense to have separate twchain, as it makes the lookup slightly more complicated, and doubles hash table memory usage. If we make sure all socket types have the lookup keys at the same offsets, we can use a generic and faster lookup. It turns out TIME_WAIT and ESTABLISHED sockets already have common lookup fields for IPv4. [ INET_TW_MATCH() is no longer needed ] I'll provide a follow-up to factorize IPv6 lookup as well, to remove INET6_TW_MATCH() This way, SYN_RECV pseudo sockets will be supported the same. A new sock_gen_put() helper is added, doing either a sock_put() or inet_twsk_put() [ and will support SYN_RECV later ]. Note this helper should only be called in real slow path, when rcu lookup found a socket that was moved to another identity (freed/reused immediately), but could eventually be used in other contexts, like sock_edemux() Before patch : dmesg | grep "TCP established" TCP established hash table entries: 524288 (order: 11, 8388608 bytes) After patch : TCP established hash table entries: 524288 (order: 10, 4194304 bytes) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-03inet: consolidate INET_TW_MATCHEric Dumazet1-18/+8
TCP listener refactoring, part 2 : We can use a generic lookup, sockets being in whatever state, if we are sure all relevant fields are at the same place in all socket types (ESTABLISH, TIME_WAIT, SYN_RECV) This patch removes these macros : inet_addrpair, inet_addrpair, tw_addrpair, tw_portpair And adds : sk_portpair, sk_addrpair, sk_daddr, sk_rcv_saddr Then, INET_TW_MATCH() is really the same than INET_MATCH() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-21inet*.h: Remove extern from function prototypesJoe Perches1-36/+36
There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin1-2/+2
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-23soreuseport: TCP/IPv4 implementationTom Herbert1-3/+10
Allow multiple listener sockets to bind to the same port. Motivation for soresuseport would be something like a web server binding to port 80 running with multiple threads, where each thread might have it's own listener socket. This could be done as an alternative to other models: 1) have one listener thread which dispatches completed connections to workers. 2) accept on a single listener socket from multiple threads. In case #1 the listener thread can easily become the bottleneck with high connection turn-over rate. In case #2, the proportion of connections accepted per thread tends to be uneven under high connection load (assuming simple event loop: while (1) { accept(); process() }, wakeup does not promote fairness among the sockets. We have seen the disproportion to be as high as 3:1 ratio between thread accepting most connections and the one accepting the fewest. With so_reusport the distribution is uniform. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-02net: fix sparse endianness warnings on sock_commonEric Dumazet1-2/+0
# make C=2 CF=-D__CHECK_ENDIAN__ net/ipv4/inet_hashtables.o ... net/ipv4/inet_hashtables.c:242:7: warning: restricted __portpair degrades to integer net/ipv4/inet_hashtables.c:242:7: warning: restricted __addrpair degrades to integer ... Move __portpair/__addrpair from include/net/inet_hashtables.h to include/net/sock.h where we need them in struct sock_common Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ling Ma <ling.ma.program@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-30net: move inet_dport/inet_num in sock_commonEric Dumazet1-22/+26
commit 68835aba4d9b (net: optimize INET input path further) moved some fields used for tcp/udp sockets lookup in the first cache line of struct sock_common. This patch moves inet_dport/inet_num as well, filling a 32bit hole on 64 bit arches and reducing number of cache line misses in lookups. Also change INET_MATCH()/INET_TW_MATCH() to perform the ports match before addresses match, as this check is more discriminant. Remove the hash check from MATCH() macros because we dont need to re validate the hash value after taking a refcount on socket, and use likely/unlikely compiler hints, as the sk_hash/hash check makes the following conditional tests 100% predicted by cpu. Introduce skc_addrpair/skc_portpair pair values to better document the alignment requirements of the port/addr pairs used in the various MATCH() macros, and remove some casts. The namespace check can also be done at last. This slightly improves TCP/UDP lookup times. IP/TCP early demux needs inet->rx_dst_ifindex and TCP needs inet->min_ttl, lets group them together in same cache line. With help from Ben Hutchings & Joe Perches. Idea of this patch came after Ling Ma proposal to move skc_hash to the beginning of struct sock_common, and should allow him to submit a final version of his patch. My tests show an improvement doing so. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Joe Perches <joe@perches.com> Cc: Ling Ma <ling.ma.program@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-19ipv4: Early TCP socket demux.David S. Miller1-2/+2
Input packet processing for local sockets involves two major demuxes. One for the route and one for the socket. But we can optimize this down to one demux for certain kinds of local sockets. Currently we only do this for established TCP sockets, but it could at least in theory be expanded to other kinds of connections. If a TCP socket is established then it's identity is fully specified. This means that whatever input route was used during the three-way handshake must work equally well for the rest of the connection since the keys will not change. Once we move to established state, we cache the receive packet's input route to use later. Like the existing cached route in sk->sk_dst_cache used for output packets, we have to check for route invalidations using dst->obsolete and dst->ops->check(). Early demux occurs outside of a socket locked section, so when a route invalidation occurs we defer the fixup of sk->sk_rx_dst until we are actually inside of established state packet processing and thus have the socket locked. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-26atomic: use <linux/atomic.h>Arun Sharma1-1/+1
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>
2010-10-21tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()Balazs Scheidler1-1/+1
When __inet_inherit_port() is called on a tproxy connection the wrong locks are held for the inet_bind_bucket it is added to. __inet_inherit_port() made an implicit assumption that the listener's port number (and thus its bind bucket). Unfortunately, if you're using the TPROXY target to redirect skbs to a transparent proxy that assumption is not true anymore and things break. This patch adds code to __inet_inherit_port() so that it can handle this case by looking up or creating a new bind bucket for the child socket and updates callers of __inet_inherit_port() to gracefully handle __inet_inherit_port() failing. Reported by and original patch from Stephen Buck <stephen.buck@exinda.com>. See http://marc.info/?t=128169268200001&r=1&w=2 for the original discussion. Signed-off-by: KOVACS Krisztian <hidden@balabit.hu> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-12-08tcp: Fix a connect() race with timewait socketsEric Dumazet1-3/+5
First patch changes __inet_hash_nolisten() and __inet6_hash() to get a timewait parameter to be able to unhash it from ehash at same time the new socket is inserted in hash. This makes sure timewait socket wont be found by a concurrent writer in __inet_check_established() 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>
2009-11-13inet: fix inet_bind_bucket_for_eachLucian Adrian Grijincu1-2/+2
The first "node" is supposed to be the cursor used in the for_each. The second "node" is ment literally and should not be macro expanded: it's the name of the hlist_node field from the inet_bind_bucket. This currently works because when inet_bind_bucket_for_each is called it's argument is still "node". Signed-off-by: Lucian Adrian Grijincu <lgrijincu@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-18inet: rename some inet_sock fieldsEric Dumazet1-6/+6
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 Dumazet1-2/+2
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>
2009-06-03net: skb->dst accessorsEric Dumazet1-1/+1
Define three accessors to get/set dst attached to a skb struct dst_entry *skb_dst(const struct sk_buff *skb) void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) void skb_dst_drop(struct sk_buff *skb) This one should replace occurrences of : dst_release(skb->dst) skb->dst = NULL; Delete skb->dst field Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01net: move bsockets outside of read only beginning of struct inet_hashinfoEric Dumazet1-1/+2
And switch bsockets to atomic_t since it might be changed in parallel. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> 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/+1
Conflicts: drivers/net/e1000/e1000_main.c
2009-01-27net: wrong test in inet_ehash_locks_alloc()Eric Dumazet1-1/+1
In commit 9db66bdcc83749affe61c61eb8ff3cf08f42afec (net: convert TCP/DCCP ehash rwlocks to spinlocks), I forgot to change one occurrence of rwlock_t to spinlock_t I believe sizeof(raw_spinlock_t) might be > 0 on !CONFIG_SMP if CONFIG_DEBUG_SPINLOCK while sizeof(raw_rwlock_t) should be 0 in this case. Fortunatly, CONFIG_DEBUG_SPINLOCK adds fields to both spinlock_t and rwlock_t, but at this might change in the future (being able to debug spinlocks but not rwlocks for example), better to be safe. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21inet: Allowing more than 64k connections and heavily optimize bind(0) time.Evgeniy Polyakov1-1/+2
With simple extension to the binding mechanism, which allows to bind more than 64k sockets (or smaller amount, depending on sysctl parameters), we have to traverse the whole bind hash table to find out empty bucket. And while it is not a problem for example for 32k connections, bind() completion time grows exponentially (since after each successful binding we have to traverse one bucket more to find empty one) even if we start each time from random offset inside the hash table. So, when hash table is full, and we want to add another socket, we have to traverse the whole table no matter what, so effectivelly this will be the worst case performance and it will be constant. Attached picture shows bind() time depending on number of already bound sockets. Green area corresponds to the usual binding to zero port process, which turns on kernel port selection as described above. Red area is the bind process, when number of reuse-bound sockets is not limited by 64k (or sysctl parameters). The same exponential growth (hidden by the green area) before number of ports reaches sysctl limit. At this time bind hash table has exactly one reuse-enbaled socket in a bucket, but it is possible that they have different addresses. Actually kernel selects the first port to try randomly, so at the beginning bind will take roughly constant time, but with time number of port to check after random start will increase. And that will have exponential growth, but because of above random selection, not every next port selection will necessary take longer time than previous. So we have to consider the area below in the graph (if you could zoom it, you could find, that there are many different times placed there), so area can hide another. Blue area corresponds to the port selection optimization. This is rather simple design approach: hashtable now maintains (unprecise and racely updated) number of currently bound sockets, and when number of such sockets becomes greater than predefined value (I use maximum port range defined by sysctls), we stop traversing the whole bind hash table and just stop at first matching bucket after random start. Above limit roughly corresponds to the case, when bind hash table is full and we turned on mechanism of allowing to bind more reuse-enabled sockets, so it does not change behaviour of other sockets. Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net> Tested-by: Denys Fedoryschenko <denys@visp.net.lb> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23net: Convert TCP/DCCP listening hash tables to use RCUEric Dumazet1-1/+8
This is the last step to be able to perform full RCU lookups in __inet_lookup() : After established/timewait tables, we add RCU lookups to listening hash table. The only trick here is that a socket of a given type (TCP ipv4, TCP ipv6, ...) can now flight between two different tables (established and listening) during a RCU grace period, so we must use different 'nulls' end-of-chain values for two tables. We define a large value : #define LISTENING_NULLS_BASE (1U << 29) So that slots in listening table are guaranteed to have different end-of-chain values than slots in established table. A reader can still detect it finished its lookup in the right chain. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-21net: use net_eq() in INET_MATCH and INET_TW_MATCHEric Dumazet1-4/+4
We can avoid some useless instructions if !CONFIG_NET_NS Because of RCU, we use INET_MATCH or INET_TW_MATCH twice for the found socket, so thats six instructions less per incoming TCP packet. Yet another tbench speedup :) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20net: convert TCP/DCCP ehash rwlocks to spinlocksEric Dumazet1-7/+7
Now TCP & DCCP use RCU lookups, we can convert ehash rwlocks to spinlocks. /proc/net/tcp and other seq_file 'readers' can safely be converted to 'writers'. This should speedup writers, since spin_lock()/spin_unlock() only use one atomic operation instead of two for write_lock()/write_unlock() Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20net: listening_hash get a spinlock per bucketEric Dumazet1-30/+15
This patch prepares RCU migration of listening_hash table for TCP/DCCP protocols. listening_hash table being small (32 slots per protocol), we add a spinlock for each slot, instead of a single rwlock for whole table. This should reduce hold time of readers, and writers concurrency. 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>
2008-11-12net: ib_net pointer should depends on CONFIG_NET_NSEric Dumazet1-0/+7
We can shrink size of "struct inet_bind_bucket" by 50%, using read_pnet() and write_pnet() Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07inet: Don't lookup the socket if there's a socket attached to the skbKOVACS Krisztian1-3/+7
Use the socket cached in the skb if it's present. Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07inet_hashtables: Add inet_lookup_skb helpersArnaldo Carvalho de Melo1-0/+14
To be able to use the cached socket reference in the skb during input processing we add a new set of lookup functions that receive the skb on their argument list. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16netns: introduce the net_hash_mix "salt" for hashesPavel Emelyanov1-2/+3
There are many possible ways to add this "salt", thus I made this patch to be the last in the series to change it if required. Currently I propose to use the struct net pointer itself as this salt, but since this pointer is most often cache-line aligned, shift this right to eliminate the bits, that are most often zeroed. After this, simply add this mix to prepared hashfn-s. For CONFIG_NET_NS=n case this salt is 0 and no changes in hashfn appear. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16inet: add struct net argument to inet_lhashfnPavel Emelyanov1-2/+2
Listening-on-one-port sockets in many namespaces produce long chains in the listening_hash-es, so prepare the inet_lhashfn to take struct net into account. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16inet: add struct net argument to inet_bhashfnPavel Emelyanov1-1/+2
Binding to some port in many namespaces may create too long chains in bhash-es, so prepare the hashfn to take struct net into account. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-17[INET]: Uninline the __inet_inherit_port call.Pavel Emelyanov1-13/+1
This deblats ~200 bytes when ipv6 and dccp are 'y'. Besides, this will ease compilation issues for patches I'm working on to make inet hash tables more scalable wrt net namespaces. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-17[INET]: Drop the inet_inherit_port() call.Pavel Emelyanov1-7/+0
As I can see from the code, two places (tcp_v6_syn_recv_sock and dccp_v6_request_recv_sock) that call this one already run with BHs disabled, so it's safe to call __inet_inherit_port there. Besides (in case I missed smth with code review) the calltrace tcp_v6_syn_recv_sock `- tcp_v4_syn_recv_sock `- __inet_inherit_port and the similar for DCCP are valid, but assumes BHs to be disabled. Signed-off-by: Pavel Emelyanov <xemul@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 Hideaki1-4/+4
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>
2008-03-22[SOCK]: Add udp_hash member to struct proto.Pavel Emelyanov1-1/+1
Inspired by the commit ab1e0a13 ([SOCK] proto: Add hashinfo member to struct proto) from Arnaldo, I made similar thing for UDP/-Lite IPv4 and -v6 protocols. The result is not that exciting, but it removes some levels of indirection in udpxxx_get_port and saves some space in code and text. The first step is to union existing hashinfo and new udp_hash on the struct proto and give a name to this union, since future initialization of tcpxxx_prot, dccp_vx_protinfo and udpxxx_protinfo will cause gcc warning about inability to initialize anonymous member this way. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-05[INET]: Fix accidentally broken inet(6)_hash_connect's port offset calculations.Pavel Emelyanov1-1/+1
The port offset calculations depend on the protocol family, but, as Adrian noticed, I broke this logic with the commit 5ee31fc1ecdcbc234c8c56dcacef87c8e09909d8 [INET]: Consolidate inet(6)_hash_connect. Return this logic back, by passing the port offset directly into the consolidated function. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Noticed-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-03[SOCK] proto: Add hashinfo member to struct protoArnaldo Carvalho de Melo1-42/+9
This way we can remove TCP and DCCP specific versions of sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port sk->sk_prot->hash: inet_hash is directly used, only v6 need a specific version to deal with mapped sockets sk->sk_prot->unhash: both v4 and v6 use inet_hash directly struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so that inet_csk_get_port can find the per family routine. Now only the lookup routines receive as a parameter a struct inet_hashtable. With this we further reuse code, reducing the difference among INET transport protocols. Eventually work has to be done on UDP and SCTP to make them share this infrastructure and get as a bonus inet_diag interfaces so that iproute can be used with these protocols. net-2.6/net/ipv4/inet_hashtables.c: struct proto | +8 struct inet_connection_sock_af_ops | +8 2 structs changed __inet_hash_nolisten | +18 __inet_hash | -210 inet_put_port | +8 inet_bind_bucket_create | +1 __inet_hash_connect | -8 5 functions changed, 27 bytes added, 218 bytes removed, diff: -191 net-2.6/net/core/sock.c: proto_seq_show | +3 1 function changed, 3 bytes added, diff: +3 net-2.6/net/ipv4/inet_connection_sock.c: inet_csk_get_port | +15 1 function changed, 15 bytes added, diff: +15 net-2.6/net/ipv4/tcp.c: tcp_set_state | -7 1 function changed, 7 bytes removed, diff: -7 net-2.6/net/ipv4/tcp_ipv4.c: tcp_v4_get_port | -31 tcp_v4_hash | -48 tcp_v4_destroy_sock | -7 tcp_v4_syn_recv_sock | -2 tcp_unhash | -179 5 functions changed, 267 bytes removed, diff: -267 net-2.6/net/ipv6/inet6_hashtables.c: __inet6_hash | +8 1 function changed, 8 bytes added, diff: +8 net-2.6/net/ipv4/inet_hashtables.c: inet_unhash | +190 inet_hash | +242 2 functions changed, 432 bytes added, diff: +432 vmlinux: 16 functions changed, 485 bytes added, 492 bytes removed, diff: -7 /home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c: tcp_v6_get_port | -31 tcp_v6_hash | -7 tcp_v6_syn_recv_sock | -9 3 functions changed, 47 bytes removed, diff: -47 /home/acme/git/net-2.6/net/dccp/proto.c: dccp_destroy_sock | -7 dccp_unhash | -179 dccp_hash | -49 dccp_set_state | -7 dccp_done | +1 5 functions changed, 1 bytes added, 242 bytes removed, diff: -241 /home/acme/git/net-2.6/net/dccp/ipv4.c: dccp_v4_get_port | -31 dccp_v4_request_recv_sock | -2 2 functions changed, 33 bytes removed, diff: -33 /home/acme/git/net-2.6/net/dccp/ipv6.c: dccp_v6_get_port | -31 dccp_v6_hash | -7 dccp_v6_request_recv_sock | +5 3 functions changed, 5 bytes added, 38 bytes removed, diff: -33 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31[NETNS]: Tcp-v4 sockets per-net lookup.Pavel Emelyanov1-21/+27
Add a net argument to inet_lookup and propagate it further into lookup calls. Plus tune the __inet_check_established. The dccp and inet_diag, which use that lookup functions pass the init_net into them. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>