Cross Reference: /net/core/dst.c

History log of /net/core/dst.c
Revision	Date	Author	Comments
f88649721268999bdff09777847080a52004f691	24-Jun-2014	Eric Dumazet <edumazet@google.com>	ipv4: fix dst race in sk_dst_get() When IP route cache had been removed in linux-3.6, we broke assumption that dst entries were all freed after rcu grace period. DST_NOCACHE dst were supposed to be freed from dst_release(). But it appears we want to keep such dst around, either in UDP sockets or tunnels. In sk_dst_get() we need to make sure dst refcount is not 0 before incrementing it, or else we might end up freeing a dst twice. DST_NOCACHE set on a dst does not mean this dst can not be attached to a socket or a tunnel. Then, before actual freeing, we need to observe a rcu grace period to make sure all other cpus can catch the fact the dst is no longer usable. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dormando <dormando@rydia.net> Signed-off-by: David S. Miller <davem@davemloft.net>
aad88724c9d54acb1a9737cb6069d8470fa85f74	15-Apr-2014	Eric Dumazet <edumazet@google.com>	ipv4: add a sock pointer to dst->output() path. In the dst->output() path for ipv4, the code assumes the skb it has to transmit is attached to an inet socket, specifically via ip_mc_output() : The sk_mc_loop() test triggers a WARN_ON() when the provider of the packet is an AF_PACKET socket. The dst->output() method gets an additional 'struct sock *sk' parameter. This needs a cascade of changes so that this parameter can be propagated from vxlan to final consumer. Fixes: 8f646c922d55 ("vxlan: keep original skb ownership") Reported-by: lucien xin <lucien.xin@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
351638e7deeed2ec8ce451b53d33921b3da68f83	28-May-2013	Jiri Pirko <jiri@resnulli.us>	net: pass info struct via netdevice notifier So far, only net_device * could be passed along with netdevice notifier event. This patch provides a possibility to pass custom structure able to provide info that event listener needs to know. Signed-off-by: Jiri Pirko <jiri@resnulli.us> v2->v3: fix typo on simeth shortened dev_getter shortened notifier_info struct name v1->v2: fix notifier_call parameter in call_netdevice_notifier() Signed-off-by: David S. Miller <davem@davemloft.net>
932bc4d7a53ba418de67fdab533248df5b36c752	21-Mar-2013	Julian Anastasov <ja@ssi.bg>	net: add skb_dst_set_noref_force Rename skb_dst_set_noref to __skb_dst_set_noref and add force flag as suggested by David Miller. The new wrapper skb_dst_set_noref_force will force dst entries that are not cached to be attached as skb dst without taking reference as long as provided dst is reclaimed after RCU grace period. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off by: Hans Schillstrom <hans@schillstrom.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Simon Horman <horms@verge.net.au>
ecd9883724b78cc72ed92c98bcb1a46c764fff21	20-Feb-2013	YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org>	ipv6: fix race condition regarding dst->expires and dst->from. Eric Dumazet wrote: \| Some strange crashes happen in rt6_check_expired(), with access \| to random addresses. \| \| At first glance, it looks like the RTF_EXPIRES and \| stuff added in commit 1716a96101c49186b \| (ipv6: fix problem with expired dst cache) \| are racy : same dst could be manipulated at the same time \| on different cpus. \| \| At some point, our stack believes rt->dst.from contains a dst pointer, \| while its really a jiffie value (as rt->dst.expires shares the same area \| of memory) \| \| rt6_update_expires() should be fixed, or am I missing something ? \| \| CC Neil because of https://bugzilla.redhat.com/show_bug.cgi?id=892060 Because we do not have any locks for dst_entry, we cannot change essential structure in the entry; e.g., we cannot change reference to other entity. To fix this issue, split 'from' and 'expires' field in dst_entry out of union. Once it is 'from' is assigned in the constructor, keep the reference until the very last stage of the life time of the object. Of course, it is unsafe to change 'from', so make rt6_set_from simple just for fresh entries. Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Reported-by: Neil Horman <nhorman@tuxdriver.com> CC: Gao Feng <gaofeng@cn.fujitsu.com> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Reported-by: Steinar H. Gunderson <sesse@google.com> Reviewed-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
0115e8e30d6fcdd4b8faa30d3ffd90859a591f51	22-Aug-2012	Eric Dumazet <edumazet@google.com>	net: remove delay at device dismantle I noticed extra one second delay in device dismantle, tracked down to a call to dst_dev_event() while some call_rcu() are still in RCU queues. These call_rcu() were posted by rt_free(struct rtable *rt) calls. We then wait a little (but one second) in netdev_wait_allrefs() before kicking again NETDEV_UNREGISTER. As the call_rcu() are now completed, dst_dev_event() can do the needed device swap on busy dst. To solve this problem, add a new NETDEV_UNREGISTER_FINAL, called after a rcu_barrier(), but outside of RTNL lock. Use NETDEV_UNREGISTER_FINAL with care ! Change dst_dev_event() handler to react to NETDEV_UNREGISTER_FINAL Also remove NETDEV_UNREGISTER_BATCH, as its not used anymore after IP cache removal. With help from Gao feng Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Mahesh Bandewar <maheshb@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
41f63c5359d14ca995172b8f6eaffd93f60fec54	03-Aug-2012	Tejun Heo <tj@kernel.org>	workqueue: use mod_delayed_work() instead of cancel + queue Convert delayed_work users doing cancel_delayed_work() followed by queue_delayed_work() to mod_delayed_work(). Most conversions are straight-forward. Ones worth mentioning are, * drivers/edac/edac_mc.c: edac_mc_workq_setup() converted to always use mod_delayed_work() and cancel loop in edac_mc_reset_delay_period() is dropped. * drivers/platform/x86/thinkpad_acpi.c: No need to remember whether watchdog is active or not. @fan_watchdog_active and related code dropped. * drivers/power/charger-manager.c: Seemingly a lot of delayed_work_pending() abuse going on here. [delayed_]work_pending() are unsynchronized and racy when used like this. I converted one instance in fullbatt_handler(). Please conver the rest so that it invokes workqueue APIs for the intended target state rather than trying to game work item pending state transitions. e.g. if timer should be modified - call mod_delayed_work(), canceled - call cancel_delayed_work[_sync](). * drivers/thermal/thermal_sys.c: thermal_zone_device_set_polling() simplified. Note that round_jiffies() calls in this function are meaningless. round_jiffies() work on absolute jiffies not delta delay used by delayed_work. v2: Tomi pointed out that __cancel_delayed_work() users can't be safely converted to mod_delayed_work(). They could be calling it from irq context and if that happens while delayed_work_timer_fn() is running, it could deadlock. __cancel_delayed_work() users are dropped. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Anton Vorontsov <cbouatmailru@gmail.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Doug Thompson <dougthompson@xmission.com> Cc: David Airlie <airlied@linux.ie> Cc: Roland Dreier <roland@kernel.org> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Len Brown <len.brown@intel.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Johannes Berg <johannes@sipsolutions.net>
a37e6e344910a43b9ebc2bbf29a029f5ea942598	07-Aug-2012	Eric Dumazet <edumazet@google.com>	net: force dst_default_metrics to const section While investigating on network performance problems, I found this little gem : $ nm -v vmlinux \| grep -1 dst_default_metrics ffffffff82736540 b busy.46605 ffffffff82736560 B dst_default_metrics ffffffff82736598 b dst_busy_list Apparently, declaring a const array without initializer put it in (writeable) bss section, in middle of possibly often dirtied cache lines. Since we really want dst_default_metrics be const to avoid any possible false sharing and catch any buggy writes, I force a null initializer. ffffffff818a4c20 R dst_default_metrics Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
54764bb647b2e847c512acf8d443df965da35000	31-Jul-2012	Eric Dumazet <eric.dumazet@gmail.com>	ipv4: Restore old dst_free() behavior. commit 404e0a8b6a55 (net: ipv4: fix RCU races on dst refcounts) tried to solve a race but added a problem at device/fib dismantle time : We really want to call dst_free() as soon as possible, even if sockets still have dst in their cache. dst_release() calls in free_fib_info_rcu() are not welcomed. Root of the problem was that now we also cache output routes (in nh_rth_output), we must use call_rcu() instead of call_rcu_bh() in rt_free(), because output route lookups are done in process context. Based on feedback and initial patch from David Miller (adding another call_rcu_bh() call in fib, but it appears it was not the right fix) I left the inet_sk_rx_dst_set() helper and added __rcu attributes to nh_rth_output and nh_rth_input to better document what is going on in this code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
404e0a8b6a55d5e1cd138c6deb1bca9abdf75d8c	30-Jul-2012	Eric Dumazet <edumazet@google.com>	net: ipv4: fix RCU races on dst refcounts commit c6cffba4ffa2 (ipv4: Fix input route performance regression.) added various fatal races with dst refcounts. crashes happen on tcp workloads if routes are added/deleted at the same time. The dst_free() calls from free_fib_info_rcu() are clearly racy. We need instead regular dst refcounting (dst_release()) and make sure dst_release() is aware of RCU grace periods : Add DST_RCU_FREE flag so that dst_release() respects an RCU grace period before dst destruction for cached dst Introduce a new inet_sk_rx_dst_set() helper, using atomic_inc_not_zero() to make sure we dont increase a zero refcount (On a dst currently waiting an rcu grace period before destruction) rt_cache_route() must take a reference on the new cached route, and release it if was not able to install it. With this patch, my machines survive various benchmarks. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
f5b0a8743601a4477419171f5046bd07d1c080a0	19-Jul-2012	David S. Miller <davem@davemloft.net>	net: Document dst->obsolete better. Add a big comment explaining how the field works, and use defines instead of magic constants for the values assigned to it. Suggested by Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net>
36bdbcae2fa2a6dfa99344d4190fcea0aa7b7c25	03-Jul-2012	David S. Miller <davem@davemloft.net>	net: Kill dst->_neighbour, accessors, and final uses. No longer used. Signed-off-by: David S. Miller <davem@davemloft.net>
5110effee8fde2edfacac9cd12a9960ab2dc39ea	02-Jul-2012	David S. Miller <davem@davemloft.net>	net: Do delayed neigh confirmation. When a dst_confirm() happens, mark the confirmation as pending in the dst. Then on the next packet out, when we have the neigh in-hand, do the update. This removes the dependency in dst_confirm() of dst's having an attached neigh. While we're here, remove the explicit 'dst' NULL check, all except 2 or 3 call sites ensure it's not NULL. So just fix those cases up. Signed-off-by: David S. Miller <davem@davemloft.net>
2721745501a26d0dc3b88c0d2f3aa11471891388	02-Dec-2011	David Miller <davem@davemloft.net>	net: Rename dst_get_neighbour{, _raw} to dst_get_neighbour_noref{, _raw}. To reflect the fact that a refrence is not obtained to the resulting neighbour entry. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Roland Dreier <roland@purestorage.com>
9de79c127cccecb11ae6a21ab1499e87aa222880	08-Aug-2011	Eric Dumazet <eric.dumazet@gmail.com>	net: fix potential neighbour race in dst_ifdown() Followup of commit f2c31e32b378a (fix NULL dereferences in check_peer_redir()). We need to make sure dst neighbour doesnt change in dst_ifdown(). Fix some sparse errors. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
69cce1d1404968f78b177a0314f5822d5afdbbfb	18-Jul-2011	David S. Miller <davem@davemloft.net>	net: Abstract dst->neighbour accesses behind helpers. dst_{get,set}_neighbour() Signed-off-by: David S. Miller <davem@davemloft.net>
f6b72b6217f8c24f2a54988e58af858b4e66024d	14-Jul-2011	David S. Miller <davem@davemloft.net>	net: Embed hh_cache inside of struct neighbour. Now that there is a one-to-one correspondance between neighbour and hh_cache entries, we no longer need: 1) dynamic allocation 2) attachment to dst->hh 3) refcounting Initialization of the hh_cache entry is indicated by hh_len being non-zero, and such initialization is always done with the neighbour's lock held as a writer. Signed-off-by: David S. Miller <davem@davemloft.net>
957c665f37007de93ccbe45902a23143724170d0	25-Jun-2011	David S. Miller <davem@davemloft.net>	ipv6: Don't put artificial limit on routing table size. IPV6, unlike IPV4, doesn't have a routing cache. Routing table entries, as well as clones made in response to route lookup requests, all live in the same table. And all of these things are together collected in the destination cache table for ipv6. This means that routing table entries count against the garbage collection limits, even though such entries cannot ever be reclaimed and are added explicitly by the administrator (rather than being created in response to lookups). Therefore it makes no sense to count ipv6 routing table entries against the GC limits. Add a DST_NOCOUNT destination cache entry flag, and skip the counting if it is set. Use this flag bit in ipv6 when adding routing table entries. Signed-off-by: David S. Miller <davem@davemloft.net>
b30c516f875004f025f4d10147bde28c5e98466b	24-May-2011	Eric Dumazet <eric.dumazet@gmail.com>	net: fix __dst_destroy_metrics_generic() dst_default_metrics is readonly, we dont want to kfree() it later. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
268bb0ce3e87872cb9290c322b0d35bce230d88f	20-May-2011	Linus Torvalds <torvalds@linux-foundation.org>	sanitize <linux/prefetch.h> usage Commit e66eed651fd1 ("list: remove prefetching from regular list iterators") removed the include of prefetch.h from list.h, which uncovered several cases that had apparently relied on that rather obscure header file dependency. So this fixes things up a bit, using grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw(' -- '.[ch]') grep -L 'prefetchw(' $(git grep -l 'linux/prefetch.h' -- '.[ch]') to guide us in finding files that either need <linux/prefetch.h> inclusion, or have it despite not needing it. There are more of them around (mostly network drivers), but this gets many core ones. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6882f933ccee5c3a86443ffc7621ce888b93ab6b	19-May-2011	David S. Miller <davem@davemloft.net>	ipv4: Kill RT_CACHE_DEBUG It's way past it's usefulness. And this gets rid of a bunch of stray ->rt_{dst,src} references. Even the comment documenting the macro was inaccurate (stated default was 1 when it's 0). If reintroduced, it should be done properly, with dynamic debug facilities. Signed-off-by: David S. Miller <davem@davemloft.net>
cf91166223772ef4a2ed98b9874958bf6a2470df	28-Apr-2011	David S. Miller <davem@davemloft.net>	net: Use non-zero allocations in dst_alloc(). Make dst_alloc() and it's users explicitly initialize the entire entry. The zero'ing done by kmem_cache_zalloc() was almost entirely redundant. Signed-off-by: David S. Miller <davem@davemloft.net>
5c1e6aa300a7a669dc469d2dcb20172c6bd8fed9	28-Apr-2011	David S. Miller <davem@davemloft.net>	net: Make dst_alloc() take more explicit initializations. Now the dst->dev, dev->obsolete, and dst->flags values can be specified as well. Signed-off-by: David S. Miller <davem@davemloft.net>
3c7bd1a14071b99d6535b710bc998ae5d3abbb66	16-Feb-2011	David S. Miller <davem@davemloft.net>	net: Add initial_ref arg to dst_alloc(). This allows avoiding multiple writes to the initial __refcnt. The most simplest cases of wanting an initial reference of "1" in ipv4 and ipv6 have been converted, the rest have been left along and kept at the existing "0". Signed-off-by: David S. Miller <davem@davemloft.net>
725d1e1b457dc2bbebb337677e73efe7c6d14da5	28-Jan-2011	David S. Miller <davem@davemloft.net>	ipv4: Attach FIB info to dst_default_metrics when possible If there are no explicit metrics attached to a route, hook fi->fib_info up to dst_default_metrics. Signed-off-by: David S. Miller <davem@davemloft.net>
62fa8a846d7de4b299232e330c74b7783539df76	27-Jan-2011	David S. Miller <davem@davemloft.net>	net: Implement read-only protection and COW'ing of metrics. Routing metrics are now copy-on-write. Initially a route entry points it's metrics at a read-only location. If a routing table entry exists, it will point there. Else it will point at the all zero metric place-holder called 'dst_default_metrics'. The writeability state of the metrics is stored in the low bits of the metrics pointer, we have two bits left to spare if we want to store more states. For the initial implementation, COW is implemented simply via kmalloc. However future enhancements will change this to place the writable metrics somewhere else, in order to increase sharing. Very likely this "somewhere else" will be the inetpeer cache. Note also that this means that metrics updates may transiently fail if we cannot COW the metrics successfully. But even by itself, this patch should decrease memory usage and increase cache locality especially for routing workloads. In those cases the read-only metric copies stay in place and never get written to. TCP workloads where metrics get updated, and those rare cases where PMTU triggers occur, will take a very slight performance hit. But that hit will be alleviated when the long-term writable metrics move to a more sharable location. Since the metrics storage went from a u32 array of RTAX_MAX entries to what is essentially a pointer, some retooling of the dst_entry layout was necessary. Most importantly, we need to preserve the alignment of the reference count so that it doesn't share cache lines with the read-mostly state, as per Eric Dumazet's alignment assertion checks. The only non-trivial bit here is the move of the 'flags' member into the writeable cacheline. This is OK since we are always accessing the flags around the same moment when we made a modification to the reference count. Signed-off-by: David S. Miller <davem@davemloft.net>
332dd96f7ac15e937088fe11f15cfe0210e8edd1	09-Nov-2010	Eric Dumazet <eric.dumazet@gmail.com>	net/dst: dst_dev_event() called after other notifiers Followup of commit ef885afbf8a37689 (net: use rcu_barrier() in rollback_registered_many) dst_dev_event() scans a garbage dst list that might be feeded by various network notifiers at device dismantle time. Its important to call dst_dev_event() after other notifiers, or we might enter the infamous msleep(250) in netdev_wait_allrefs(), and wait one second before calling again call_netdevice_notifiers(NETDEV_UNREGISTER, dev) to properly remove last device references. Use priority -10 to let dst_dev_notifier be called after other network notifiers (they have the default 0 priority) Reported-by: Ben Greear <greearb@candelatech.com> Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reported-by: Octavian Purdila <opurdila@ixiacom.com> Reported-by: Benjamin LaHaise <bcrl@kvack.org> Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
27b75c95f10d249574d9c4cb9dab878107faede8	15-Oct-2010	Eric Dumazet <eric.dumazet@gmail.com>	net: avoid RCU for NOCACHE dst There is no point using RCU for dst we allocate for a very short time (used once). Change dst_release() to take DST_NOCACHE into account, but also change skb_dst_set_noref() to force a refcount increment for such dst. This is a _huge_ gain, because we dont waste memory to store xx thousand of dsts. Instead of queueing them to RCU, we can free them instantly. CPU caches can stay hot, re-using same memory blocks to hold temporary dsts. Note : remove unneeded smp_mb__before_atomic_dec(); in dst_release(), since atomic_dec_return() implies a full memory barrier. Stress test, 160.000.000 udp frames sent, IP route cache disabled (DDOS). Before: real 0m38.091s user 0m13.189s sys 7m53.018s After: real 0m29.946s user 0m12.157s sys 7m40.605s For reference, if IP route cache was enabled : real 0m32.030s user 0m10.521s sys 8m15.243s Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
fc66f95c68b6d4535a0ea2ea15d5cf626e310956	08-Oct-2010	Eric Dumazet <eric.dumazet@gmail.com>	net dst: use a percpu_counter to track entries struct dst_ops tracks number of allocated dst in an atomic_t field, subject to high cache line contention in stress workload. Switch to a percpu_counter, to reduce number of time we need to dirty a central location. Place it on a separate cache line to avoid dirtying read only fields. Stress test : (Sending 160.000.000 UDP frames, IP route cache disabled, dual E5540 @2.53GHz, 32bit kernel, FIB_TRIE, SLUB/NUMA) Before: real 0m51.179s user 0m15.329s sys 10m15.942s After: real 0m45.570s user 0m15.525s sys 9m56.669s With a small reordering of struct neighbour fields, subject of a following patch, (to separate refcnt from other read mostly fields) real 0m41.841s user 0m15.261s sys 8m45.949s Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
34d101dd6204bd100fc2e6f7b5f9a10f959ce2c9	11-Oct-2010	Eric Dumazet <eric.dumazet@gmail.com>	neigh: speedup neigh_hh_init() When a new dst is used to send a frame, neigh_resolve_output() tries to associate an struct hh_cache to this dst, calling neigh_hh_init() with the neigh rwlock write locked. Most of the time, hh_cache is already known and linked into neighbour, so we find it and increment its refcount. This patch changes the logic so that we call neigh_hh_init() with neighbour lock read locked only, so that fast path can be run in parallel by concurrent cpus. This brings part of the speedup we got with commit c7d4426a98a5f (introduce DST_NOCACHE flag) for non cached dsts, even for cached ones, removing one of the contention point that routers hit on multiqueue enabled machines. Further improvements would need to use a seqlock instead of an rwlock to protect neigh->ha[], to not dirty neigh too often and remove two atomic ops. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
d79d991379af35d43f003f162e8650e72965b8ca	20-Jul-2010	Nicolas Dichtel <nicolas.dichtel@6wind.com>	__dst_free(): put EXPORT_SYMBOLS after the fct Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
561155110307ad304226a23272244398fa46cbae	12-Apr-2010	stephen hemminger <shemminger@vyatta.com>	dst: don't inline dst_ifdown The function dst_ifdown is called only two places but in a non- performance critical code path, there is no reason to inline it. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
598ed9367a36ee1fd4ae3271a54a3547a33975a5	29-Mar-2010	laurent chavey <chavey@google.com>	fix net/core/dst.c coding style error and warnings Fix coding style errors and warnings output while running checkpatch.pl on the file net/core/dst.c. Signed-off-by: chavey <chavey@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
5a0e3ad6af8660be21ca98a971cd00f331318c05	24-Mar-2010	Tejun Heo <tj@kernel.org>	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2fc1b5dd99f66d93ffc23fd8df82d384c1a354c8	09-Feb-2010	Eric Dumazet <eric.dumazet@gmail.com>	dst: call cond_resched() in dst_gc_task() Kernel bugzilla #15239 On some workloads, it is quite possible to get a huge dst list to process in dst_gc_task(), and trigger soft lockup detection. Fix is to call cond_resched(), as we run in process context. Reported-by: Pawel Staszewski <pstaszewski@itcare.pl> Tested-by: Pawel Staszewski <pstaszewski@itcare.pl> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
ef711cf1d156428d4c2911b8c86c6ce90519dc45	14-Nov-2008	Eric Dumazet <dada1@cosmosbay.com>	net: speedup dst_release() During tbench/oprofile sessions, I found that dst_release() was in third position. CPU: Core 2, speed 2999.68 MHz (estimated) Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit mask of 0x00 (Unhalted core cycles) count 100000 samples % symbol name 483726 9.0185 __copy_user_zeroing_intel 191466 3.5697 __copy_user_intel 185475 3.4580 dst_release 175114 3.2648 ip_queue_xmit 153447 2.8608 tcp_sendmsg 108775 2.0280 tcp_recvmsg 102659 1.9140 sysenter_past_esp 101450 1.8914 tcp_current_mss 95067 1.7724 __copy_from_user_ll 86531 1.6133 tcp_transmit_skb Of course, all CPUS fight on the dst_entry associated with 127.0.0.1 Instead of first checking the refcount value, then decrement it, we use atomic_dec_return() to help CPU to make the right memory transaction (ie getting the cache line in exclusive mode) dst_release() is now at the fifth position, and tbench a litle bit faster ;) CPU: Core 2, speed 3000.1 MHz (estimated) Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit mask of 0x00 (Unhalted core cycles) count 100000 samples % symbol name 647107 8.8072 __copy_user_zeroing_intel 258840 3.5229 ip_queue_xmit 258302 3.5155 __copy_user_intel 209629 2.8531 tcp_sendmsg 165632 2.2543 dst_release 149232 2.0311 tcp_current_mss 147821 2.0119 tcp_recvmsg 137893 1.8767 sysenter_past_esp 127473 1.7349 __copy_from_user_ll 121308 1.6510 ip_finish_output 118510 1.6129 tcp_transmit_skb 109295 1.4875 tcp_v4_rcv Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
f262b59becc3f557da6460232abac13706402849	13-Sep-2008	Benjamin Thery <benjamin.thery@bull.net>	net: fix scheduling of dst_gc_task by __dst_free The dst garbage collector dst_gc_task() may not be scheduled as we expect it to be in __dst_free(). Indeed, when the dst_gc_timer was replaced by the delayed_work dst_gc_work, the mod_timer() call used to schedule the garbage collector at an earlier date was replaced by a schedule_delayed_work() (see commit 86bba269d08f0c545ae76c90b56727f65d62d57f). But, the behaviour of mod_timer() and schedule_delayed_work() is different in the way they handle the delay. mod_timer() stops the timer and re-arm it with the new given delay, whereas schedule_delayed_work() only check if the work is already queued in the workqueue (and queue it (with delay) if it is not) BUT it does NOT take into account the new delay (even if the new delay is earlier in time). schedule_delayed_work() returns 0 if it didn't queue the work, but we don't check the return code in __dst_free(). If I understand the code in __dst_free() correctly, we want dst_gc_task to be queued after DST_GC_INC jiffies if we pass the test (and not in some undetermined time in the future), so I think we should add a call to cancel_delayed_work() before schedule_delayed_work(). Patch below. Or we should at least test the return code of schedule_delayed_work(), and reset the values of dst_garbage.timer_inc and dst_garbage.timer_expires back to their former values if schedule_delayed_work() failed. Otherwise the subsequent calls to __dst_free will test the wrong values and assume wrong thing about when the garbage collector is supposed to be scheduled. dst_gc_task() also calls schedule_delayed_work() without checking its return code (or calling cancel_scheduled_work() first), but it should fine there: dst_gc_task is the routine of the delayed_work, so no dst_gc_work should be pending in the queue when it's running. Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Acked-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
8d3308687f7f1eaa1bb5d202d14752d5f90068eb	28-Mar-2008	Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>	[NET]: uninline dst_release Codiff stats (allyesconfig, v2.6.24-mm1): -16420 187 funcs, 103 +, 16523 -, diff: -16420 --- dst_release Without number of debug related CONFIGs (v2.6.25-rc2-mm1): -7257 186 funcs, 70 +, 7327 -, diff: -7257 --- dst_release dst_release \| +40 Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
c346dca10840a874240c78efe3f39acf4312a1f2	25-Mar-2008	YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>	[NET] NETNS: Omit net_device->nd_net without CONFIG_NET_NS. Introduce per-net_device inlines: dev_net(), dev_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>
9de8f76d200342f1e9495861c2c9ce87a6bc26d0	29-Feb-2008	Denis V. Lunev <den@openvz.org>	[NETNS]: DST cleanup routines should be called inside namespace. Device inside the namespace can be started and downed. So, active routing cache should be cleaned up on device stop. Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>