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2009-08-28fib_trie: resize reworkJens Låås
Here is rework and cleanup of the resize function. Some bugs we had. We were using ->parent when we should use node_parent(). Also we used ->parent which is not assigned by inflate in inflate loop. Also a fix to set thresholds to power 2 to fit halve and double strategy. max_resize is renamed to max_work which better indicates it's function. Reaching max_work is not an error, so warning is removed. max_work only limits amount of work done per resize. (limits CPU-usage, outstanding memory etc). The clean-up makes it relatively easy to add fixed sized root-nodes if we would like to decrease the memory pressure on routers with large routing tables and dynamic routing. If we'll need that... Its been tested with 280k routes. Work done together with Robert Olsson. Signed-off-by: Jens Låås <jens.laas@its.uu.se> Signed-off-by: Robert Olsson <robert.olsson@its.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-05net: mark read-only arrays as constJan Engelhardt
String literals are constant, and usually, we can also tag the array of pointers const too, moving it to the .rodata section. Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-20ipv4: fib_trie: Use tnode_get_child_rcu() and node_parent_rcu() in lookupsJarek Poplawski
While looking for other fib_trie problems reported by Pawel Staszewski I noticed there are a few uses of tnode_get_child() and node_parent() in lookups instead of their rcu versions. Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-20ipv4: Fix inflate_threshold_root automaticallyJarek Poplawski
During large updates there could be triggered warnings like: "Fix inflate_threshold_root. Now=25 size=11 bits" if inflate() of the root node isn't finished in 10 loops. It should be much rarer now, after changing the threshold from 15 to 25, and a temporary problem, so this patch tries to handle it automatically using a fix variable to increase by one inflate threshold for next root resizes (up to the 35 limit, max fix = 10). The fix variable is decreased when root's inflate() finishes below 7 loops (even if some other, smaller table/ trie is updated -- for simplicity the fix variable is global for now). Reported-by: Pawel Staszewski <pstaszewski@itcare.pl> Reported-by: Jorge Boncompte [DTI2] <jorge@dti2.net> Tested-by: Pawel Staszewski <pstaszewski@itcare.pl> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: Robert Olsson <robert.olsson@its.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-20ipv4: Use synchronize_rcu() during trie_rebalance()Jarek Poplawski
During trie_rebalance() we free memory after resizing with call_rcu(), but large updates, especially with PREEMPT_NONE configs, can cause memory stresses, so this patch calls synchronize_rcu() in tnode_free_flush() after each sync_pages to guarantee such freeing (especially before resizing the root node). The value of sync_pages = 128 is based on Pawel Staszewski's tests as the lowest which doesn't hinder updating times. (For testing purposes there was a sysfs module parameter to change it on demand, but it's removed until we're sure it could be really useful.) The patch is based on suggestions by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reported-by: Pawel Staszewski <pstaszewski@itcare.pl> Tested-by: Pawel Staszewski <pstaszewski@itcare.pl> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-08ipv4: Fix fib_trie rebalancing, part 4 (root thresholds)Jarek Poplawski
Pawel Staszewski wrote: <blockquote> Some time ago i report this: http://bugzilla.kernel.org/show_bug.cgi?id=6648 and now with 2.6.29 / 2.6.29.1 / 2.6.29.3 and 2.6.30 it back dmesg output: oprofile: using NMI interrupt. Fix inflate_threshold_root. Now=15 size=11 bits ... Fix inflate_threshold_root. Now=15 size=11 bits cat /proc/net/fib_triestat Basic info: size of leaf: 40 bytes, size of tnode: 56 bytes. Main: Aver depth: 2.28 Max depth: 6 Leaves: 276539 Prefixes: 289922 Internal nodes: 66762 1: 35046 2: 13824 3: 9508 4: 4897 5: 2331 6: 1149 7: 5 9: 1 18: 1 Pointers: 691228 Null ptrs: 347928 Total size: 35709 kB </blockquote> It seems, the current threshold for root resizing is too aggressive, and it causes misleading warnings during big updates, but it might be also responsible for memory problems, especially with non-preempt configs, when RCU freeing is delayed long after call_rcu. It should be also mentioned that because of non-atomic changes during resizing/rebalancing the current lookup algorithm can miss valid leaves so it's additional argument to shorten these activities even at a cost of a minimally longer searching. This patch restores values before the patch "[IPV4]: fib_trie root node settings", commit: 965ffea43d4ebe8cd7b9fee78d651268dd7d23c5 from v2.6.22. Pawel's report: <blockquote> I dont see any big change of (cpu load or faster/slower routing/propagating routes from bgpd or something else) - in avg there is from 2% to 3% more of CPU load i dont know why but it is - i change from "preempt" to "no preempt" 3 times and check this my "mpstat -P ALL 1 30" always avg cpu load was from 2 to 3% more compared to "no preempt" [...] cat /proc/net/fib_triestat Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes. Main: Aver depth: 2.44 Max depth: 6 Leaves: 277814 Prefixes: 291306 Internal nodes: 66420 1: 32737 2: 14850 3: 10332 4: 4871 5: 2313 6: 942 7: 371 8: 3 17: 1 Pointers: 599098 Null ptrs: 254865 Total size: 18067 kB </blockquote> According to this and other similar reports average depth is slightly increased (~0.2), and root nodes are shorter (log 17 vs. 18), but there is no visible performance decrease. So, until memory handling is improved or added parameters for changing this individually, this patch resets to safer defaults. Reported-by: Pawel Staszewski <pstaszewski@itcare.pl> Reported-by: Jorge Boncompte [DTI2] <jorge@dti2.net> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Tested-by: Pawel Staszewski <pstaszewski@itcare.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-30ipv4: Fix fib_trie rebalancing, part 3Jarek Poplawski
Alas current delaying of freeing old tnodes by RCU in trie_rebalance is still not enough because we can free a top tnode before updating a t->trie pointer. Reported-by: Pawel Staszewski <pstaszewski@itcare.pl> Tested-by: Pawel Staszewski <pstaszewski@itcare.pl> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-18ipv4: Fix fib_trie rebalancing, part 2Jarek Poplawski
My previous patch, which explicitly delays freeing of tnodes by adding them to the list to flush them after the update is finished, isn't strict enough. It treats exceptionally tnodes without parent, assuming they are newly created, so "invisible" for the read side yet. But the top tnode doesn't have parent as well, so we have to exclude all exceptions (at least until a better way is found). Additionally we need to move rcu assignment of this node before flushing, so the return type of the trie_rebalance() function is changed. Reported-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-15ipv4: Fix fib_trie rebalancingJarek Poplawski
While doing trie_rebalance(): resize(), inflate(), halve() RCU free tnodes before updating their parents. It depends on RCU delaying the real destruction, but if RCU readers start after call_rcu() and before parent update they could access freed memory. It is currently prevented with preempt_disable() on the update side, but it's not safe, except maybe classic RCU, plus it conflicts with memory allocations with GFP_KERNEL flag used from these functions. This patch explicitly delays freeing of tnodes by adding them to the list, which is flushed after the update is finished. Reported-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/ath/ath5k/phy.c drivers/net/wireless/iwlwifi/iwl-agn.c drivers/net/wireless/iwlwifi/iwl3945-base.c
2009-05-21ipv4: Fix oops with FIB_TRIERobert Olsson
It seems we can fix this by disabling preemption while we re-balance the trie. This is with the CONFIG_CLASSIC_RCU. It's been stress-tested at high loads continuesly taking a full BGP table up/down via iproute -batch. Note. fib_trie is not updated for CONFIG_PREEMPT_RCU Reported-by: Andrei Popa Signed-off-by: Robert Olsson <robert.olsson@its.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-18ipv4: cleanup - remove two unused parameters from fib_semantic_match().Rami Rosen
Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-31net: replace NIPQUAD() in net/ipv4/ net/ipv6/Harvey Harrison
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u can be replaced with %pI4 Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-18proc: consolidate per-net single-release callersPavel Emelyanov
They are symmetrical to single_open ones :) Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-18proc: consolidate per-net single_open callersPavel Emelyanov
There are already 7 of them - time to kill some duplicate code. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-14Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/netfilter/nf_conntrack_proto_tcp.c
2008-07-10ipv4: fib_trie: Fix lookup error returnBen Hutchings
In commit a07f5f508a4d9728c8e57d7f66294bf5b254ff7f "[IPV4] fib_trie: style cleanup", the changes to check_leaf() and fn_trie_lookup() were wrong - where fn_trie_lookup() would previously return a negative error value from check_leaf(), it now returns 0. Now fn_trie_lookup() doesn't appear to care about plen, so we can revert check_leaf() to returning the error value. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Tested-by: William Boughton <bill@boughton.de> Acked-by: Stephen Heminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05netns: add namespace parameter to rt_cache_flushDenis V. Lunev
Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-11net: remove CVS keywordsAdrian Bunk
This patch removes CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-24[NET]: Fix heavy stack usage in seq_file output routines.Pavel Emelyanov
Plan C: we can follow the Al Viro's proposal about %n like in this patch. The same applies to udp, fib (the /proc/net/route file), rt_cache and sctp debug. This is minus ~150-200 bytes for each. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-14[IPV4]: Use NIPQUAD_FMT to format ipv4 addresses.YOSHIFUJI Hideaki
And use %u to format port. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-10ipv4: fib_trie leaf free optimizationStephen Hemminger
Avoid unneeded test in the case where object to be freed has to be a leaf. Don't need to use the generic tnode_free() function, instead just setup leaf to be freed. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-10ipv4: fib_trie remove unused argumentStephen Hemminger
The trie pointer is passed down to flush_list and flush_leaf but never used. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-10IPV4: fib_trie use vmalloc for large tnodesStephen Hemminger
Use vmalloc rather than alloc_pages to avoid wasting memory. The problem is that tnode structure has a power of 2 sized array, plus a header. So the current code wastes almost half the memory allocated because it always needs the next bigger size to hold that small header. This is similar to an earlier patch by Eric, but instead of a list and lock, I used a workqueue to handle the fact that vfree can't be done in interrupt context. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[NET] NETNS: Omit seq_net_private->net without CONFIG_NET_NS.YOSHIFUJI Hideaki
Without CONFIG_NET_NS, no namespace other than &init_net exists, no need to store net in seq_net_private. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-23Merge branch 'master' of ../net-2.6/David S. Miller
Conflicts: net/ipv6/ndisc.c
2008-03-23fib_trie: print information on all routing tablesStephen Hemminger
Make /proc/net/fib_trie and /proc/net/fib_triestat display all routing tables, not just local and main. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-22[IPV4] fib_trie: fix warning from rcu_assign_poingerStephen Hemminger
This gets rid of a warning caused by the test in rcu_assign_pointer. I tried to fix rcu_assign_pointer, but that devolved into a long set of discussions about doing it right that came to no real solution. Since the test in rcu_assign_pointer for constant NULL would never succeed in fib_trie, just open code instead. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-12fib_trie: /proc/net/route performance improvementStephen Hemminger
Use key/offset caching to change /proc/net/route (use by iputils route) from O(n^2) to O(n). This improves performance from 30sec with 160,000 routes to 1sec. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-12fib_trie: handle empty treeStephen Hemminger
This fixes possible problems when trie_firstleaf() returns NULL to trie_leafindex(). Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-05[IPV4]: Formatting fix for /proc/net/fib_trie.Denis V. Lunev
The line in the /proc/net/fib_trie for route with TOS specified - has extra \n at the end - does not have a space after route scope like below. |-- 1.1.1.1 /32 universe UNICASTtos =1 Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31[IPV4] fib_trie: rescan if key is lost during dumpStephen Hemminger
Normally during a dump the key of the last dumped entry is used for continuation, but since lock is dropped it might be lost. In that case fallback to the old counter based N^2 behaviour. This means the dump will end up skipping some routes which matches what FIB_HASH does. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31[IPV4] fib_trie: apply fixes from fib_hashJulian Anastasov
Update fib_trie with some fib_hash fixes: - check for duplicate alternative routes for prefix+tos+priority when replacing route - properly insert by matching tos together with priority - fix alias walking to use list_for_each_entry_continue for insertion and deletion when fa_head is not NULL - copy state from fa to new_fa on replace (not a problem for now) - additionally, avoid replacement without error if new route is same, as Joonwoo Park suggests. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: remove unneeded NULL checkStephen Hemminger
Since fib_route_seq_show now uses hlist_for_each_entry(), the leaf info can not be NULL. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: More whitespace cleanup.Stephen Hemminger
Remove extra blank lines. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: avoid rescan on dumpStephen Hemminger
This converts dumping (and flushing) of large route tables form O(N^2) to O(N). If the route dump took multiple pages then the dump routine gets called again. The old code kept track of location by counter, the new code instead uses the last key. This is a really big win ( 0.3 sec vs 12 sec) for big route tables. One side effect is that if the table changes during the dump, then the last key will not be found, and we will return -EBUSY. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: avoid extra search on deleteStephen Hemminger
Get rid of extra search that made route deletion O(n). Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: dump table in sorted orderStephen Hemminger
It is easier with TRIE to dump the data traversal rather than interating over every possible prefix. This saves some time and makes the dump come out in sorted order. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: iterator recodeStephen Hemminger
Remove the complex loop structure of nextleaf() and replace it with a simpler tree walker. This improves the performance and is much cleaner. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: dump message multiple part flagStephen Hemminger
Match fib_hash, and set NLM_F_MULTI to handle multiple part messages. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: use hash listStephen Hemminger
The code to dump can use the existing hash chain rather than doing repeated lookup. Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: compute size when neededStephen Hemminger
Compute the number of prefixes when needed, rather than doing bookeeping. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: style cleanupStephen Hemminger
Style cleanups: * make check_leaf return -1 or plen, rather than by reference * Get rid of #ifdef that is always set * split out embedded function calls in if statements. * checkpatch warnings Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: put leaf nodes in a slab cacheStephen Hemminger
This improves locality for operations that touch all the leaves. Save space since these entries don't need to be hardware cache aligned. Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[FIB]: Fix rcu_dereference() abuses in fib_trie.cEric Dumazet
node_parent() and tnode_get_child() currently use rcu_dereference(). These functions are called from both - readers only paths (where rcu_dereference() is needed), and - writer path (where rcu_dereference() is not needed) To make explicit where rcu_dereference() is really needed, I introduced new node_parent_rcu() and tnode_get_child_rcu() functions which use rcu_dereference(), while node_parent() and tnode_get_child() dont use it. Then I changed calling sites where rcu_dereference() was really needed to call the _rcu() variants. This should have no impact but for alpha architecture, and may help future sparse checks. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4]: fib hash|trie initializationStephen Hemminger
Initialization of the slab cache's should be done when IP is initialized to make sure of available memory, and that code can be marked __init. Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: size and statisticsStephen Hemminger
Show number of entries in trie, the size field was being set but never used, but it only counted leaves, not all entries. Refactor the two cases in fib_triestat_seq_show into a single routine. Note: the stat structure was being malloc'd but the stack usage isn't so high (288 bytes) that it is worth the additional complexity. Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[FIB]: Avoid using static variables without proper lockingEric Dumazet
fib_trie_seq_show() uses two helper functions, rtn_scope() and rtn_type() that can write to static storage without locking. Just pass to them a temporary buffer to avoid potential corruption (probably not triggerable but still...) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[FIB]: full_children & empty_children should be uint, not ushortEric Dumazet
If declared as unsigned short, these fields can overflow, and whole trie logic is broken. I could not make the machine crash, but some tnode can never be freed. Note for 64 bit arches : By reordering t_key and parent in [node, leaf, tnode] structures, we can use 32 bits hole after t_key so that sizeof(struct tnode) doesnt change after this patch. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Robert Olsson <robert.olsson@its.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPV4] fib_trie: removes a memset() call in tnode_new()Eric Dumazet
tnode_alloc() already clears allocated memory, using kcalloc() or alloc_pages(GFP_KERNEL|__GFP_ZERO, ...) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>