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2014-12-10net: replace remaining users of arch_fast_hash with jhashDaniel Borkmann1-4/+4
This patch effectively reverts commit 500f80872645 ("net: ovs: use CRC32 accelerated flow hash if available"), and other remaining arch_fast_hash() users such as from nfsd via commit 6282cd565553 ("NFSD: Don't hand out delegations for 30 seconds after recalling them.") where it has been used as a hash function for bloom filtering. While we think that these users are actually not much of concern, it has been requested to remove the arch_fast_hash() library bits that arose from [1] entirely as per recent discussion [2]. The main argument is that using it as a hash may introduce bias due to its linearity (see avalanche criterion) and thus makes it less clear (though we tried to document that) when this security/performance trade-off is actually acceptable for a general purpose library function. Lets therefore avoid any further confusion on this matter and remove it to prevent any future accidental misuse of it. For the time being, this is going to make hashing of flow keys a bit more expensive in the ovs case, but future work could reevaluate a different hashing discipline. [1] https://patchwork.ozlabs.org/patch/299369/ [2] https://patchwork.ozlabs.org/patch/418756/ Cc: Neil Brown <neilb@suse.de> Cc: Francesco Fusco <fusco@ntop.org> Cc: Jesse Gross <jesse@nicira.com> Cc: Thomas Graf <tgraf@suug.ch> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-24rhashtable: Check for count mismatch while iterating in selftestThomas Graf1-7/+20
Verify whether both the lock and RCU protected iterators see all test entries before and after expanding and shrinking has been performed. Also verify whether the number of entries in the hashtable remains stable during expansion and shrinking. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-5/+5
Conflicts: drivers/net/ethernet/chelsio/cxgb4vf/sge.c drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c sge.c was overlapping two changes, one to use the new __dev_alloc_page() in net-next, and one to use s->fl_pg_order in net. ixgbe_phy.c was a set of overlapping whitespace changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13rhashtable: Drop gfp_flags arg in insert/remove functionsThomas Graf1-24/+17
Reallocation is only required for shrinking and expanding and both rely on a mutex for synchronization and callers of rhashtable_init() are in non atomic context. Therefore, no reason to continue passing allocation hints through the API. Instead, use GFP_KERNEL and add __GFP_NOWARN | __GFP_NORETRY to allow for silent fall back to vzalloc() without the OOM killer jumping in as pointed out by Eric Dumazet and Eric W. Biederman. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13rhashtable: Add parent argument to mutex_is_heldHerbert Xu1-2/+2
Currently mutex_is_held can only test locks in the that are global since it takes no arguments. This prevents rhashtable from being used in places where locks are lock, e.g., per-namespace locks. This patch adds a parent field to mutex_is_held and rhashtable_params so that local locks can be used (and tested). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13rhashtable: Move mutex_is_held under PROVE_LOCKINGHerbert Xu1-0/+8
The rhashtable function mutex_is_held is only used when PROVE_LOCKING is enabled. This patch makes the mutex_is_held field in rhashtable optional depending on PROVE_LOCKING. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13lib: rhashtable - Remove weird non-ASCII characters from commentsHerbert Xu1-5/+5
My editor spewed garbage that looked like memory corruption on my screen. It turns out that a number of occurences of "fi" got turned into a ligature. This patch replaces these ligatures with the ASCII letters "fi". Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Cheers, Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-4/+8
Pull networking updates from David Miller: "Most notable changes in here: 1) By far the biggest accomplishment, thanks to a large range of contributors, is the addition of multi-send for transmit. This is the result of discussions back in Chicago, and the hard work of several individuals. Now, when the ->ndo_start_xmit() method of a driver sees skb->xmit_more as true, it can choose to defer the doorbell telling the driver to start processing the new TX queue entires. skb->xmit_more means that the generic networking is guaranteed to call the driver immediately with another SKB to send. There is logic added to the qdisc layer to dequeue multiple packets at a time, and the handling mis-predicted offloads in software is now done with no locks held. Finally, pktgen is extended to have a "burst" parameter that can be used to test a multi-send implementation. Several drivers have xmit_more support: i40e, igb, ixgbe, mlx4, virtio_net Adding support is almost trivial, so export more drivers to support this optimization soon. I want to thank, in no particular or implied order, Jesper Dangaard Brouer, Eric Dumazet, Alexander Duyck, Tom Herbert, Jamal Hadi Salim, John Fastabend, Florian Westphal, Daniel Borkmann, David Tat, Hannes Frederic Sowa, and Rusty Russell. 2) PTP and timestamping support in bnx2x, from Michal Kalderon. 3) Allow adjusting the rx_copybreak threshold for a driver via ethtool, and add rx_copybreak support to enic driver. From Govindarajulu Varadarajan. 4) Significant enhancements to the generic PHY layer and the bcm7xxx driver in particular (EEE support, auto power down, etc.) from Florian Fainelli. 5) Allow raw buffers to be used for flow dissection, allowing drivers to determine the optimal "linear pull" size for devices that DMA into pools of pages. The objective is to get exactly the necessary amount of headers into the linear SKB area pre-pulled, but no more. The new interface drivers use is eth_get_headlen(). From WANG Cong, with driver conversions (several had their own by-hand duplicated implementations) by Alexander Duyck and Eric Dumazet. 6) Support checksumming more smoothly and efficiently for encapsulations, and add "foo over UDP" facility. From Tom Herbert. 7) Add Broadcom SF2 switch driver to DSA layer, from Florian Fainelli. 8) eBPF now can load programs via a system call and has an extensive testsuite. Alexei Starovoitov and Daniel Borkmann. 9) Major overhaul of the packet scheduler to use RCU in several major areas such as the classifiers and rate estimators. From John Fastabend. 10) Add driver for Intel FM10000 Ethernet Switch, from Alexander Duyck. 11) Rearrange TCP_SKB_CB() to reduce cache line misses, from Eric Dumazet. 12) Add Datacenter TCP congestion control algorithm support, From Florian Westphal. 13) Reorganize sk_buff so that __copy_skb_header() is significantly faster. From Eric Dumazet" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1558 commits) netlabel: directly return netlbl_unlabel_genl_init() net: add netdev_txq_bql_{enqueue, complete}_prefetchw() helpers net: description of dma_cookie cause make xmldocs warning cxgb4: clean up a type issue cxgb4: potential shift wrapping bug i40e: skb->xmit_more support net: fs_enet: Add NAPI TX net: fs_enet: Remove non NAPI RX r8169:add support for RTL8168EP net_sched: copy exts->type in tcf_exts_change() wimax: convert printk to pr_foo() af_unix: remove 0 assignment on static ipv6: Do not warn for informational ICMP messages, regardless of type. Update Intel Ethernet Driver maintainers list bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING tipc: fix bug in multicast congestion handling net: better IFF_XMIT_DST_RELEASE support net/mlx4_en: remove NETDEV_TX_BUSY 3c59x: fix bad split of cpu_to_le32(pci_map_single()) net: bcmgenet: fix Tx ring priority programming ...
2014-10-07Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivialLinus Torvalds1-2/+2
Pull "trivial tree" updates from Jiri Kosina: "Usual pile from trivial tree everyone is so eagerly waiting for" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) Remove MN10300_PROC_MN2WS0038 mei: fix comments treewide: Fix typos in Kconfig kprobes: update jprobe_example.c for do_fork() change Documentation: change "&" to "and" in Documentation/applying-patches.txt Documentation: remove obsolete pcmcia-cs from Changes Documentation: update links in Changes Documentation: Docbook: Fix generated DocBook/kernel-api.xml score: Remove GENERIC_HAS_IOMAP gpio: fix 'CONFIG_GPIO_IRQCHIP' comments tty: doc: Fix grammar in serial/tty dma-debug: modify check_for_stack output treewide: fix errors in printk genirq: fix reference in devm_request_threaded_irq comment treewide: fix synchronize_rcu() in comments checkstack.pl: port to AArch64 doc: queue-sysfs: minor fixes init/do_mounts: better syntax description MIPS: fix comment spelling powerpc/simpleboot: fix comment ...
2014-10-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+4
Conflicts: drivers/net/usb/r8152.c net/netfilter/nfnetlink.c Both r8152 and nfnetlink conflicts were simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller1-4/+4
Pablo Neira Ayuso says: ==================== nf pull request for net This series contains netfilter fixes for net, they are: 1) Fix lockdep splat in nft_hash when releasing sets from the rcu_callback context. We don't the mutex there anymore. 2) Remove unnecessary spinlock_bh in the destroy path of the nf_tables rbtree set type from rcu_callback context. 3) Fix another lockdep splat in rhashtable. None of the callers hold a mutex when calling rhashtable_destroy. 4) Fix duplicated error reporting from nfnetlink when aborting and replaying a batch. 5) Fix a Kconfig issue reported by kbuild robot. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+0
Conflicts: arch/mips/net/bpf_jit.c drivers/net/can/flexcan.c Both the flexcan and MIPS bpf_jit conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-19lib: rhashtable: remove second linux/log2.h inclusionFabian Frederick1-1/+0
linux/log2.h was included twice. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-03lib/rhashtable: allow user to set the minimum shifts of shrinkingYing Xue1-4/+8
Although rhashtable library allows user to specify a quiet big size for user's created hash table, the table may be shrunk to a very small size - HASH_MIN_SIZE(4) after object is removed from the table at the first time. Subsequently, even if the total amount of objects saved in the table is quite lower than user's initial setting in a long time, the hash table size is still dynamically adjusted by rhashtable_shrink() or rhashtable_expand() each time object is inserted or removed from the table. However, as synchronize_rcu() has to be called when table is shrunk or expanded by the two functions, we should permit user to set the minimum table size through configuring the minimum number of shifts according to user specific requirement, avoiding these expensive actions of shrinking or expanding because of calling synchronize_rcu(). Signed-off-by: Ying Xue <ying.xue@windriver.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-03rhashtable: fix lockdep splat in rhashtable_destroy()Pablo Neira Ayuso1-4/+4
No need for rht_dereference() from rhashtable_destroy() since the existing callers don't hold the mutex when invoking this function from: 1) Netlink, this is called in case of memory allocation errors in the initialization path, no nl_sk_hash_lock is held. 2) Netfilter, this is called from the rcu callback, no nfnl_lock is held either. I think it's reasonable to assume that the caller has to make sure that no hash resizing may happen before releasing the bucket array. Therefore, the caller should be responsible for releasing this in a safe way, document this to make people aware of it. This resolves a rcu lockdep splat in nft_hash: =============================== [ INFO: suspicious RCU usage. ] 3.16.0+ #178 Not tainted ------------------------------- lib/rhashtable.c:596 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 1 lock held by ksoftirqd/2/18: #0: (rcu_callback){......}, at: [<ffffffff810918fd>] rcu_process_callbacks+0x27e/0x4c7 stack backtrace: CPU: 2 PID: 18 Comm: ksoftirqd/2 Not tainted 3.16.0+ #178 Hardware name: LENOVO 23259H1/23259H1, BIOS G2ET32WW (1.12 ) 05/30/2012 0000000000000001 ffff88011706bb68 ffffffff8143debc 0000000000000000 ffff880117062610 ffff88011706bb98 ffffffff81077515 ffff8800ca041a50 0000000000000004 ffff8800ca386480 ffff8800ca041a00 ffff88011706bbb8 Call Trace: [<ffffffff8143debc>] dump_stack+0x4e/0x68 [<ffffffff81077515>] lockdep_rcu_suspicious+0xfa/0x103 [<ffffffff81228b1b>] rhashtable_destroy+0x46/0x52 [<ffffffffa06f21a7>] nft_hash_destroy+0x73/0x82 [nft_hash] Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Thomas Graf <tgraf@suug.ch>
2014-08-26lib: rhashtable: Spelling s/compuate/compute/Geert Uytterhoeven1-2/+2
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Thomas Graf <tgraf@suug.ch> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-08-14rhashtable: unexport and make rht_obj() staticThomas Graf1-7/+1
No need to export rht_obj(), all inner to outer object translations occur internally. It was intended to be used with rht_for_each() which now primarily serves as the iterator for rhashtable_remove_pprev() to effectively flush and free the full table. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14rhashtable: RCU annotations for next pointersThomas Graf1-1/+1
Properly annotate next pointers as access is RCU protected in the lookup path. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02lib: Resizable, Scalable, Concurrent Hash TableThomas Graf1-0/+797
Generic implementation of a resizable, scalable, concurrent hash table based on [0]. The implementation supports both, fixed size keys specified via an offset and length, or arbitrary keys via own hash and compare functions. Lookups are lockless and protected as RCU read side critical sections. Automatic growing/shrinking based on user configurable watermarks is available while allowing concurrent lookups to take place. Objects to be hashed must include a struct rhash_head. The reason for not using the existing struct hlist_head is that the expansion and shrinking will have two buckets point to a single entry which would lead in obscure reverse chaining behaviour. Code includes a boot selftest if CONFIG_TEST_RHASHTABLE is defined. [0] https://www.usenix.org/legacy/event/atc11/tech/final_files/Triplett.pdf Signed-off-by: Thomas Graf <tgraf@suug.ch> Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>