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2016-11-28net, sched: respect rcu grace period on cls destructionDaniel Borkmann1-4/+3
Roi reported a crash in flower where tp->root was NULL in ->classify() callbacks. Reason is that in ->destroy() tp->root is set to NULL via RCU_INIT_POINTER(). It's problematic for some of the classifiers, because this doesn't respect RCU grace period for them, and as a result, still outstanding readers from tc_classify() will try to blindly dereference a NULL tp->root. The tp->root object is strictly private to the classifier implementation and holds internal data the core such as tc_ctl_tfilter() doesn't know about. Within some classifiers, such as cls_bpf, cls_basic, etc, tp->root is only checked for NULL in ->get() callback, but nowhere else. This is misleading and seemed to be copied from old classifier code that was not cleaned up properly. For example, d3fa76ee6b4a ("[NET_SCHED]: cls_basic: fix NULL pointer dereference") moved tp->root initialization into ->init() routine, where before it was part of ->change(), so ->get() had to deal with tp->root being NULL back then, so that was indeed a valid case, after d3fa76ee6b4a, not really anymore. We used to set tp->root to NULL long ago in ->destroy(), see 47a1a1d4be29 ("pkt_sched: remove unnecessary xchg() in packet classifiers"); but the NULLifying was reintroduced with the RCUification, but it's not correct for every classifier implementation. In the cases that are fixed here with one exception of cls_cgroup, tp->root object is allocated and initialized inside ->init() callback, which is always performed at a point in time after we allocate a new tp, which means tp and thus tp->root was not globally visible in the tp chain yet (see tc_ctl_tfilter()). Also, on destruction tp->root is strictly kfree_rcu()'ed in ->destroy() handler, same for the tp which is kfree_rcu()'ed right when we return from ->destroy() in tcf_destroy(). This means, the head object's lifetime for such classifiers is always tied to the tp lifetime. The RCU callback invocation for the two kfree_rcu() could be out of order, but that's fine since both are independent. Dropping the RCU_INIT_POINTER(tp->root, NULL) for these classifiers here means that 1) we don't need a useless NULL check in fast-path and, 2) that outstanding readers of that tp in tc_classify() can still execute under respect with RCU grace period as it is actually expected. Things that haven't been touched here: cls_fw and cls_route. They each handle tp->root being NULL in ->classify() path for historic reasons, so their ->destroy() implementation can stay as is. If someone actually cares, they could get cleaned up at some point to avoid the test in fast path. cls_u32 doesn't set tp->root to NULL. For cls_rsvp, I just added a !head should anyone actually be using/testing it, so it at least aligns with cls_fw and cls_route. For cls_flower we additionally need to defer rhashtable destruction (to a sleepable context) after RCU grace period as concurrent readers might still access it. (Note that in this case we need to hold module reference to keep work callback address intact, since we only wait on module unload for all call_rcu()s to finish.) This fixes one race to bring RCU grace period guarantees back. Next step as worked on by Cong however is to fix 1e052be69d04 ("net_sched: destroy proto tp when all filters are gone") to get the order of unlinking the tp in tc_ctl_tfilter() for the RTM_DELTFILTER case right by moving RCU_INIT_POINTER() before tcf_destroy() and let the notification for removal be done through the prior ->delete() callback. Both are independant issues. Once we have that right, we can then clean tp->root up for a number of classifiers by not making them RCU pointers, which requires a new callback (->uninit) that is triggered from tp's RCU callback, where we just kfree() tp->root from there. Fixes: 1f947bf151e9 ("net: sched: rcu'ify cls_bpf") Fixes: 9888faefe132 ("net: sched: cls_basic use RCU") Fixes: 70da9f0bf999 ("net: sched: cls_flow use RCU") Fixes: 77b9900ef53a ("tc: introduce Flower classifier") Fixes: bf3994d2ed31 ("net/sched: introduce Match-all classifier") Fixes: 952313bd6258 ("net: sched: cls_cgroup use RCU") Reported-by: Roi Dayan <roid@mellanox.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Roi Dayan <roid@mellanox.com> Cc: Jiri Pirko <jiri@mellanox.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23net_sched: properly handle failure case of tcf_exts_init()WANG Cong1-3/+10
After commit 22dc13c837c3 ("net_sched: convert tcf_exts from list to pointer array") we do dynamic allocation in tcf_exts_init(), therefore we need to handle the ENOMEM case properly. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20cls_cgroup: factor out classid retrievalDaniel Borkmann1-21/+2
Split out retrieving the cgroups net_cls classid retrieval into its own function, so that it can be reused later on from other parts of the traffic control subsystem. If there's no skb->sk, then the small helper returns 0 as well, which in cls_cgroup terms means 'could not classify'. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09net_sched: destroy proto tp when all filters are goneCong Wang1-1/+5
Kernel automatically creates a tp for each (kind, protocol, priority) tuple, which has handle 0, when we add a new filter, but it still is left there after we remove our own, unless we don't specify the handle (literally means all the filters under the tuple). For example this one is left: # tc filter show dev eth0 filter parent 8001: protocol arp pref 49152 basic The user-space is hard to clean up these for kernel because filters like u32 are organized in a complex way. So kernel is responsible to remove it after all filters are gone. Each type of filter has its own way to store the filters, so each type has to provide its way to check if all filters are gone. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim<jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-10net: sched: cls: use nla_nest_cancel instead of nlmsg_trimJiri Pirko1-2/+1
To cancel nesting, this function is more convenient. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09net: sched: cls: remove unused op put from tcf_proto_opsJiri Pirko1-5/+0
It is never called and implementations are void. So just remove it. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09net_sched: cls_cgroup: remove unnecessary ifJiri Pirko1-5/+1
since head->handle == handle (checked before), just assign handle. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07net: sched: cls_cgroup tear down exts and ematch from rcu callbackJohn Fastabend1-3/+1
It is not RCU safe to destroy the action chain while there is a possibility of readers accessing it. Move this code into the rcu callback using the same rcu callback used in the code patch to make a change to head. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07net: sched: remove tcf_proto from ematch callsJohn Fastabend1-2/+2
This removes the tcf_proto argument from the ematch code paths that only need it to reference the net namespace. This allows simplifying qdisc code paths especially when we need to tear down the ematch from an RCU callback. In this case we can not guarentee that the tcf_proto structure is still valid. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-29net_sched: remove the first parameter from tcf_exts_destroy()WANG Cong1-3/+3
Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <hadi@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-17net: sched: cls_cgroup need tcf_exts_init in all casesJohn Fastabend1-4/+3
This ensures the tcf_exts_init() is called for all cases. Fixes: 952313bd62589cae216a57 ("net: sched: cls_cgroup use RCU") Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16net: sched: cls_cgroup fix possible memory leak of 'new'John Fastabend1-4/+9
tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master head: 54996b529ab70ca1d6f40677cd2698c4f7127e87 commit: c7953ef23042b7c4fc2be5ecdd216aacff6df5eb [625/646] net: sched: cls_cgroup use RCU net/sched/cls_cgroup.c:130 cls_cgroup_change() warn: possible memory leak of 'new' net/sched/cls_cgroup.c:135 cls_cgroup_change() warn: possible memory leak of 'new' net/sched/cls_cgroup.c:139 cls_cgroup_change() warn: possible memory leak of 'new' Fixes: c7953ef23042b7c4fc2be5ecdd216aac ("net: sched: cls_cgroup use RCU") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13net: sched: cls_cgroup use RCUJohn Fastabend1-24/+39
Make cgroup classifier safe for RCU. Also drops the calls in the classify routine that were doing a rcu_read_lock()/rcu_read_unlock(). If the rcu_read_lock() isn't held entering this routine we have issues with deleting the classifier chain so remove the unnecessary rcu_read_lock()/rcu_read_unlock() pair noting all paths AFAIK hold rcu_read_lock. If there is a case where classify is called without the rcu read lock then an rcu splat will occur and we can correct it. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-28sched, cls: check if we could overwrite actions when changing a filterCong Wang1-2/+2
When actions are attached to a filter, they are a part of the filter itself, so when changing a filter we should allow to overwrite the actions inside as well. In my specific case, when I tried to _append_ a new action to an existing filter which already has an action, I got EEXIST since kernel refused to overwrite the existing one in kernel. This patch checks if we are changing the filter checking NLM_F_CREATE flag (Sigh, filters don't use NLM_F_REPLACE...) and then passes the boolean down to actions. This fixes the problem above. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13net_sched: add struct net pointer to tcf_proto_ops->dumpWANG Cong1-1/+1
It will be needed by the next patch. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller1-110/+1
Pablo Neira Ayuso says: ==================== netfilter/IPVS updates for net-next The following patchset contains Netfilter updates for your net-next tree, they are: * Add full port randomization support. Some crazy researchers found a way to reconstruct the secure ephemeral ports that are allocated in random mode by sending off-path bursts of UDP packets to overrun the socket buffer of the DNS resolver to trigger retransmissions, then if the timing for the DNS resolution done by a client is larger than usual, then they conclude that the port that received the burst of UDP packets is the one that was opened. It seems a bit aggressive method to me but it seems to work for them. As a result, Daniel Borkmann and Hannes Frederic Sowa came up with a new NAT mode to fully randomize ports using prandom. * Add a new classifier to x_tables based on the socket net_cls set via cgroups. These includes two patches to prepare the field as requested by Zefan Li. Also from Daniel Borkmann. * Use prandom instead of get_random_bytes in several locations of the netfilter code, from Florian Westphal. * Allow to use the CTA_MARK_MASK in ctnetlink when mangling the conntrack mark, also from Florian Westphal. * Fix compilation warning due to unused variable in IPVS, from Geert Uytterhoeven. * Add support for UID/GID via nfnetlink_queue, from Valentina Giusti. * Add IPComp extension to x_tables, from Fan Du. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-04net: net_cls: move cgroupfs classid handling into coreDaniel Borkmann1-110/+1
Zefan Li requested [1] to perform the following cleanup/refactoring: - Split cgroupfs classid handling into net core to better express a possible more generic use. - Disable module support for cgroupfs bits as the majority of other cgroupfs subsystems do not have that, and seems to be not wished from cgroup side. Zefan probably might want to follow-up for netprio later on. - By this, code can be further reduced which previously took care of functionality built when compiled as module. cgroupfs bits are being placed under net/core/netclassid_cgroup.c, so that we are consistent with {netclassid,netprio}_cgroup naming that is under net/core/ as suggested by Zefan. No change in functionality, but only code refactoring that is being done here. [1] http://patchwork.ozlabs.org/patch/304825/ Suggested-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Zefan Li <lizefan@huawei.com> Cc: Thomas Graf <tgraf@suug.ch> Cc: cgroups@vger.kernel.org Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-01-03net: revert "sched classifier: make cgroup table local"Cong Wang1-1/+1
This reverts commit de6fb288b1246a5c4e00c0cdbfe3a838a360b3f4. Otherwise we got: net/sched/cls_cgroup.c:106:29: error: static declaration of ‘net_cls_subsys’ follows non-static declaration static struct cgroup_subsys net_cls_subsys = { ^ In file included from include/linux/cgroup.h:654:0, from net/sched/cls_cgroup.c:18: include/linux/cgroup_subsys.h:35:29: note: previous declaration of ‘net_cls_subsys’ was here SUBSYS(net_cls) ^ make[2]: *** [net/sched/cls_cgroup.o] Error 1 Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-02sched classifier: make cgroup table localstephen hemminger1-1/+1
Doesn't need to be global. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18net_sched: cls: refactor out struct tcf_ext_mapWANG Cong1-10/+5
These information can be saved in tcf_exts, and this will simplify the code. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18net_sched: act: use standard struct list_headWANG Cong1-0/+1
Currently actions are chained by a singly linked list, therefore it is a bit hard to add and remove a specific entry. Convert it to struct list_head so that in the latter patch we can remove an action without finding its head. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-09cgroup: cls: remove unnecessary task_cls_classidGao feng1-2/+2
We can get classid through cgroup_subsys_state, this is directviewing and effective. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09cgroup: make cgroup_taskset deal with cgroup_subsys_state instead of cgroupTejun Heo1-1/+1
cgroup is in the process of converting to css (cgroup_subsys_state) from cgroup as the principal subsystem interface handle. This is mostly to prepare for the unified hierarchy support where css's will be created and destroyed dynamically but also helps cleaning up subsystem implementations as css is usually what they are interested in anyway. cgroup_taskset which is used by the subsystem attach methods is the last cgroup subsystem API which isn't using css as the handle. Update cgroup_taskset_cur_cgroup() to cgroup_taskset_cur_css() and cgroup_taskset_for_each() to take @skip_css instead of @skip_cgrp. The conversions are pretty mechanical. One exception is cpuset::cgroup_cs(), which lost its last user and got removed. This patch shouldn't introduce any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org>
2013-08-09cgroup: pass around cgroup_subsys_state instead of cgroup in file methodsTejun Heo1-9/+5
cgroup is currently in the process of transitioning to using struct cgroup_subsys_state * as the primary handle instead of struct cgroup. Please see the previous commit which converts the subsystem methods for rationale. This patch converts all cftype file operations to take @css instead of @cgroup. cftypes for the cgroup core files don't have their subsytem pointer set. These will automatically use the dummy_css added by the previous patch and can be converted the same way. Most subsystem conversions are straight forwards but there are some interesting ones. * freezer: update_if_frozen() is also converted to take @css instead of @cgroup for consistency. This will make the code look simpler too once iterators are converted to use css. * memory/vmpressure: mem_cgroup_from_css() needs to be exported to vmpressure while mem_cgroup_from_cont() can be made static. Updated accordingly. * cpu: cgroup_tg() doesn't have any user left. Removed. * cpuacct: cgroup_ca() doesn't have any user left. Removed. * hugetlb: hugetlb_cgroup_form_cgroup() doesn't have any user left. Removed. * net_cls: cgrp_cls_state() doesn't have any user left. Removed. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Aristeu Rozanski <aris@redhat.com> Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Steven Rostedt <rostedt@goodmis.org>
2013-08-09cgroup: pass around cgroup_subsys_state instead of cgroup in subsystem methodsTejun Heo1-8/+10
cgroup is currently in the process of transitioning to using struct cgroup_subsys_state * as the primary handle instead of struct cgroup * in subsystem implementations for the following reasons. * With unified hierarchy, subsystems will be dynamically bound and unbound from cgroups and thus css's (cgroup_subsys_state) may be created and destroyed dynamically over the lifetime of a cgroup, which is different from the current state where all css's are allocated and destroyed together with the associated cgroup. This in turn means that cgroup_css() should be synchronized and may return NULL, making it more cumbersome to use. * Differing levels of per-subsystem granularity in the unified hierarchy means that the task and descendant iterators should behave differently depending on the specific subsystem the iteration is being performed for. * In majority of the cases, subsystems only care about its part in the cgroup hierarchy - ie. the hierarchy of css's. Subsystem methods often obtain the matching css pointer from the cgroup and don't bother with the cgroup pointer itself. Passing around css fits much better. This patch converts all cgroup_subsys methods to take @css instead of @cgroup. The conversions are mostly straight-forward. A few noteworthy changes are * ->css_alloc() now takes css of the parent cgroup rather than the pointer to the new cgroup as the css for the new cgroup doesn't exist yet. Knowing the parent css is enough for all the existing subsystems. * In kernel/cgroup.c::offline_css(), unnecessary open coded css dereference is replaced with local variable access. This patch shouldn't cause any behavior differences. v2: Unnecessary explicit cgrp->subsys[] deref in css_online() replaced with local variable @css as suggested by Li Zefan. Rebased on top of new for-3.12 which includes for-3.11-fixes so that ->css_free() invocation added by da0a12caff ("cgroup: fix a leak when percpu_ref_init() fails") is converted too. Suggested by Li Zefan. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Aristeu Rozanski <aris@redhat.com> Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Steven Rostedt <rostedt@goodmis.org>
2013-08-09cgroup: add css_parent()Tejun Heo1-3/+5
Currently, controllers have to explicitly follow the cgroup hierarchy to find the parent of a given css. cgroup is moving towards using cgroup_subsys_state as the main controller interface construct, so let's provide a way to climb the hierarchy using just csses. This patch implements css_parent() which, given a css, returns its parent. The function is guarnateed to valid non-NULL parent css as long as the target css is not at the top of the hierarchy. freezer, cpuset, cpu, cpuacct, hugetlb, memory, net_cls and devices are converted to use css_parent() instead of accessing cgroup->parent directly. * __parent_ca() is dropped from cpuacct and its usage is replaced with parent_ca(). The only difference between the two was NULL test on cgroup->parent which is now embedded in css_parent() making the distinction moot. Note that eventually a css->parent field will be added to css and the NULL check in css_parent() will go away. This patch shouldn't cause any behavior differences. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-09cgroup: add/update accessors which obtain subsys specific data from cssTejun Heo1-4/+7
css (cgroup_subsys_state) is usually embedded in a subsys specific data structure. Subsystems either use container_of() directly to cast from css to such data structure or has an accessor function wrapping such cast. As cgroup as whole is moving towards using css as the main interface handle, add and update such accessors to ease dealing with css's. All accessors explicitly handle NULL input and return NULL in those cases. While this looks like an extra branch in the code, as all controllers specific data structures have css as the first field, the casting doesn't involve any offsetting and the compiler can trivially optimize out the branch. * blkio, freezer, cpuset, cpu, cpuacct and net_cls didn't have such accessor. Added. * memory, hugetlb and devices already had one but didn't explicitly handle NULL input. Updated. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-09cgroup: s/cgroup_subsys_state/cgroup_css/ s/task_subsys_state/task_css/Tejun Heo1-2/+2
The names of the two struct cgroup_subsys_state accessors - cgroup_subsys_state() and task_subsys_state() - are somewhat awkward. The former clashes with the type name and the latter doesn't even indicate it's somehow related to cgroup. We're about to revamp large portion of cgroup API, so, let's rename them so that they're less awkward. Most per-controller usages of the accessors are localized in accessor wrappers and given the amount of scheduled changes, this isn't gonna add any noticeable headache. Rename cgroup_subsys_state() to cgroup_css() and task_subsys_state() to task_css(). This patch is pure rename. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-01-15pkt_sched: namespace aware act_mirredBenjamin LaHaise1-2/+3
Eric Dumazet pointed out that act_mirred needs to find the current net_ns, and struct net pointer is not provided in the call chain. His original patch made use of current->nsproxy->net_ns to find the network namespace, but this fails to work correctly for userspace code that makes use of netlink sockets in different network namespaces. Instead, pass the "struct net *" down along the call chain to where it is needed. This version removes the ifb changes as Eric has submitted that patch separately, but is otherwise identical to the previous version. Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-0/+24
Pull networking changes from David Miller: 1) Allow to dump, monitor, and change the bridge multicast database using netlink. From Cong Wang. 2) RFC 5961 TCP blind data injection attack mitigation, from Eric Dumazet. 3) Networking user namespace support from Eric W. Biederman. 4) tuntap/virtio-net multiqueue support by Jason Wang. 5) Support for checksum offload of encapsulated packets (basically, tunneled traffic can still be checksummed by HW). From Joseph Gasparakis. 6) Allow BPF filter access to VLAN tags, from Eric Dumazet and Daniel Borkmann. 7) Bridge port parameters over netlink and BPDU blocking support from Stephen Hemminger. 8) Improve data access patterns during inet socket demux by rearranging socket layout, from Eric Dumazet. 9) TIPC protocol updates and cleanups from Ying Xue, Paul Gortmaker, and Jon Maloy. 10) Update TCP socket hash sizing to be more in line with current day realities. The existing heurstics were choosen a decade ago. From Eric Dumazet. 11) Fix races, queue bloat, and excessive wakeups in ATM and associated drivers, from Krzysztof Mazur and David Woodhouse. 12) Support DOVE (Distributed Overlay Virtual Ethernet) extensions in VXLAN driver, from David Stevens. 13) Add "oops_only" mode to netconsole, from Amerigo Wang. 14) Support set and query of VEB/VEPA bridge mode via PF_BRIDGE, also allow DCB netlink to work on namespaces other than the initial namespace. From John Fastabend. 15) Support PTP in the Tigon3 driver, from Matt Carlson. 16) tun/vhost zero copy fixes and improvements, plus turn it on by default, from Michael S. Tsirkin. 17) Support per-association statistics in SCTP, from Michele Baldessari. And many, many, driver updates, cleanups, and improvements. Too numerous to mention individually. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits) net/mlx4_en: Add support for destination MAC in steering rules net/mlx4_en: Use generic etherdevice.h functions. net: ethtool: Add destination MAC address to flow steering API bridge: add support of adding and deleting mdb entries bridge: notify mdb changes via netlink ndisc: Unexport ndisc_{build,send}_skb(). uapi: add missing netconf.h to export list pkt_sched: avoid requeues if possible solos-pci: fix double-free of TX skb in DMA mode bnx2: Fix accidental reversions. bna: Driver Version Updated to 3.1.2.1 bna: Firmware update bna: Add RX State bna: Rx Page Based Allocation bna: TX Intr Coalescing Fix bna: Tx and Rx Optimizations bna: Code Cleanup and Enhancements ath9k: check pdata variable before dereferencing it ath5k: RX timestamp is reported at end of frame ath9k_htc: RX timestamp is reported at end of frame ...
2012-11-22netcls_cgroup: move config inheritance to ->css_online() and remove ↵Tejun Heo1-12/+8
.broken_hierarchy marking It turns out that we'll have to live with attributes which are inherited at cgroup creation time but not affected by further updates to the parent afterwards - such attributes are already in wide use e.g. for cpuset. So, there's nothing to do for netcls_cgroup for hierarchy support. Its current behavior - inherit only during creation - is good enough. Move config inheriting from ->css_alloc() to ->css_online() for consistency, which doesn't change behavior at all, and remove .broken_hierarchy marking. Signed-off-by: Tejun Heo <tj@kernel.org> Tested-and-Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: David S. Miller <davem@davemloft.net>
2012-11-19cgroup: rename ->create/post_create/pre_destroy/destroy() to ↵Tejun Heo1-4/+4
->css_alloc/online/offline/free() Rename cgroup_subsys css lifetime related callbacks to better describe what their roles are. Also, update documentation. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2012-10-26cgroup: net_cls: Rework update socket logicDaniel Wagner1-0/+24
The cgroup logic part of net_cls is very similar as the one in net_prio. Let's stream line the net_cls logic with the net_prio one. The net_prio update logic was changed by following commit (note there were some changes necessary later on) commit 406a3c638ce8b17d9704052c07955490f732c2b8 Author: John Fastabend <john.r.fastabend@intel.com> Date: Fri Jul 20 10:39:25 2012 +0000 net: netprio_cgroup: rework update socket logic Instead of updating the sk_cgrp_prioidx struct field on every send this only updates the field when a task is moved via cgroup infrastructure. This allows sockets that may be used by a kernel worker thread to be managed. For example in the iscsi case today a user can put iscsid in a netprio cgroup and control traffic will be sent with the correct sk_cgrp_prioidx value set but as soon as data is sent the kernel worker thread isssues a send and sk_cgrp_prioidx is updated with the kernel worker threads value which is the default case. It seems more correct to only update the field when the user explicitly sets it via control group infrastructure. This allows the users to manage sockets that may be used with other threads. Since classid is now updated when the task is moved between the cgroups, we don't have to call sock_update_classid() from various places to ensure we always using the latest classid value. [v2: Use iterate_fd() instead of open coding] Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Li Zefan <lizefan@huawei.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Joe Perches <joe@perches.com> Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Stanislav Kinsbursky <skinsbursky@parallels.com> Cc: Tejun Heo <tj@kernel.org> Cc: <netdev@vger.kernel.org> Cc: <cgroups@vger.kernel.org> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-02Merge branch 'for-linus' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace changes from Eric Biederman: "This is a mostly modest set of changes to enable basic user namespace support. This allows the code to code to compile with user namespaces enabled and removes the assumption there is only the initial user namespace. Everything is converted except for the most complex of the filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs, nfs, ocfs2 and xfs as those patches need a bit more review. The strategy is to push kuid_t and kgid_t values are far down into subsystems and filesystems as reasonable. Leaving the make_kuid and from_kuid operations to happen at the edge of userspace, as the values come off the disk, and as the values come in from the network. Letting compile type incompatible compile errors (present when user namespaces are enabled) guide me to find the issues. The most tricky areas have been the places where we had an implicit union of uid and gid values and were storing them in an unsigned int. Those places were converted into explicit unions. I made certain to handle those places with simple trivial patches. Out of that work I discovered we have generic interfaces for storing quota by projid. I had never heard of the project identifiers before. Adding full user namespace support for project identifiers accounts for most of the code size growth in my git tree. Ultimately there will be work to relax privlige checks from "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing root in a user names to do those things that today we only forbid to non-root users because it will confuse suid root applications. While I was pushing kuid_t and kgid_t changes deep into the audit code I made a few other cleanups. I capitalized on the fact we process netlink messages in the context of the message sender. I removed usage of NETLINK_CRED, and started directly using current->tty. Some of these patches have also made it into maintainer trees, with no problems from identical code from different trees showing up in linux-next. After reading through all of this code I feel like I might be able to win a game of kernel trivial pursuit." Fix up some fairly trivial conflicts in netfilter uid/git logging code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits) userns: Convert the ufs filesystem to use kuid/kgid where appropriate userns: Convert the udf filesystem to use kuid/kgid where appropriate userns: Convert ubifs to use kuid/kgid userns: Convert squashfs to use kuid/kgid where appropriate userns: Convert reiserfs to use kuid and kgid where appropriate userns: Convert jfs to use kuid/kgid where appropriate userns: Convert jffs2 to use kuid and kgid where appropriate userns: Convert hpfs to use kuid and kgid where appropriate userns: Convert btrfs to use kuid/kgid where appropriate userns: Convert bfs to use kuid/kgid where appropriate userns: Convert affs to use kuid/kgid wherwe appropriate userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids userns: On ia64 deal with current_uid and current_gid being kuid and kgid userns: On ppc convert current_uid from a kuid before printing. userns: Convert s390 getting uid and gid system calls to use kuid and kgid userns: Convert s390 hypfs to use kuid and kgid where appropriate userns: Convert binder ipc to use kuids userns: Teach security_path_chown to take kuids and kgids userns: Add user namespace support to IMA userns: Convert EVM to deal with kuids and kgids in it's hmac computation ...
2012-10-02Merge branch 'for-3.7-hierarchy' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup hierarchy update from Tejun Heo: "Currently, different cgroup subsystems handle nested cgroups completely differently. There's no consistency among subsystems and the behaviors often are outright broken. People at least seem to agree that the broken hierarhcy behaviors need to be weeded out if any progress is gonna be made on this front and that the fallouts from deprecating the broken behaviors should be acceptable especially given that the current behaviors don't make much sense when nested. This patch makes cgroup emit warning messages if cgroups for subsystems with broken hierarchy behavior are nested to prepare for fixing them in the future. This was put in a separate branch because more related changes were expected (didn't make it this round) and the memory cgroup wanted to pull in this and make changes on top." * 'for-3.7-hierarchy' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: mark subsystems with broken hierarchy support and whine if cgroups are nested for them
2012-09-14cgroup: mark subsystems with broken hierarchy support and whine if cgroups ↵Tejun Heo1-0/+9
are nested for them Currently, cgroup hierarchy support is a mess. cpu related subsystems behave correctly - configuration, accounting and control on a parent properly cover its children. blkio and freezer completely ignore hierarchy and treat all cgroups as if they're directly under the root cgroup. Others show yet different behaviors. These differing interpretations of cgroup hierarchy make using cgroup confusing and it impossible to co-mount controllers into the same hierarchy and obtain sane behavior. Eventually, we want full hierarchy support from all subsystems and probably a unified hierarchy. Users using separate hierarchies expecting completely different behaviors depending on the mounted subsystem is deterimental to making any progress on this front. This patch adds cgroup_subsys.broken_hierarchy and sets it to %true for controllers which are lacking in hierarchy support. The goal of this patch is two-fold. * Move users away from using hierarchy on currently non-hierarchical subsystems, so that implementing proper hierarchy support on those doesn't surprise them. * Keep track of which controllers are broken how and nudge the subsystems to implement proper hierarchy support. For now, start with a single warning message. We can whine louder later on. v2: Fixed a typo spotted by Michal. Warning message updated. v3: Updated memcg part so that it doesn't generate warning in the cases where .use_hierarchy=false doesn't make the behavior different from root.use_hierarchy=true. Fixed a typo spotted by Glauber. v4: Check ->broken_hierarchy after cgroup creation is complete so that ->create() can affect the result per Michal. Dropped unnecessary memcg root handling per Michal. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Turner <pjt@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2012-09-14cgroup: Assign subsystem IDs during compile timeDaniel Wagner1-13/+0
WARNING: With this change it is impossible to load external built controllers anymore. In case where CONFIG_NETPRIO_CGROUP=m and CONFIG_NET_CLS_CGROUP=m is set, corresponding subsys_id should also be a constant. Up to now, net_prio_subsys_id and net_cls_subsys_id would be of the type int and the value would be assigned during runtime. By switching the macro definition IS_SUBSYS_ENABLED from IS_BUILTIN to IS_ENABLED, all *_subsys_id will have constant value. That means we need to remove all the code which assumes a value can be assigned to net_prio_subsys_id and net_cls_subsys_id. A close look is necessary on the RCU part which was introduces by following patch: commit f845172531fb7410c7fb7780b1a6e51ee6df7d52 Author: Herbert Xu <herbert@gondor.apana.org.au> Mon May 24 09:12:34 2010 Committer: David S. Miller <davem@davemloft.net> Mon May 24 09:12:34 2010 cls_cgroup: Store classid in struct sock Tis code was added to init_cgroup_cls() /* We can't use rcu_assign_pointer because this is an int. */ smp_wmb(); net_cls_subsys_id = net_cls_subsys.subsys_id; respectively to exit_cgroup_cls() net_cls_subsys_id = -1; synchronize_rcu(); and in module version of task_cls_classid() rcu_read_lock(); id = rcu_dereference(net_cls_subsys_id); if (id >= 0) classid = container_of(task_subsys_state(p, id), struct cgroup_cls_state, css)->classid; rcu_read_unlock(); Without an explicit explaination why the RCU part is needed. (The rcu_deference was fixed by exchanging it to rcu_derefence_index_check() in a later commit, but that is a minor detail.) So here is my pondering why it was introduced and why it safe to remove it now. Note that this code was copied over to net_prio the reasoning holds for that subsystem too. The idea behind the RCU use for net_cls_subsys_id is to make sure we get a valid pointer back from task_subsys_state(). task_subsys_state() is just blindly accessing the subsys array and returning the pointer. Obviously, passing in -1 as id into task_subsys_state() returns an invalid value (out of lower bound). So this code makes sure that only after module is loaded and the subsystem registered, the id is assigned. Before unregistering the module all old readers must have left the critical section. This is done by assigning -1 to the id and issuing a synchronized_rcu(). Any new readers wont call task_subsys_state() anymore and therefore it is safe to unregister the subsystem. The new code relies on the same trick, but it looks at the subsys pointer return by task_subsys_state() (remember the id is constant and therefore we allways have a valid index into the subsys array). No precautions need to be taken during module loading module. Eventually, all CPUs will get a valid pointer back from task_subsys_state() because rebind_subsystem() which is called after the module init() function will assigned subsys[net_cls_subsys_id] the newly loaded module subsystem pointer. When the subsystem is about to be removed, rebind_subsystem() will called before the module exit() function. In this case, rebind_subsys() will assign subsys[net_cls_subsys_id] a NULL pointer and then it calls synchronize_rcu(). All old readers have left by then the critical section. Any new reader wont access the subsystem anymore. At this point we are safe to unregister the subsystem. No synchronize_rcu() call is needed. Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Gao feng <gaofeng@cn.fujitsu.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: netdev@vger.kernel.org Cc: cgroups@vger.kernel.org
2012-08-15net sched: Pass the skb into change so it can access NETLINK_CBEric W. Biederman1-1/+2
cls_flow.c plays with uids and gids. Unless I misread that code it is possible for classifiers to depend on the specific uid and gid values. Therefore I need to know the user namespace of the netlink socket that is installing the packet classifiers. Pass in the rtnetlink skb so I can access the NETLINK_CB of the passed packet. In particular I want access to sk_user_ns(NETLINK_CB(in_skb).ssk). Pass in not the user namespace but the incomming rtnetlink skb into the the classifier change routines as that is generally the more useful parameter. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-04-01cgroup: convert all non-memcg controllers to the new cftype interfaceTejun Heo1-6/+2
Convert debug, freezer, cpuset, cpu_cgroup, cpuacct, net_prio, blkio, net_cls and device controllers to use the new cftype based interface. Termination entry is added to cftype arrays and populate callbacks are replaced with cgroup_subsys->base_cftypes initializations. This is functionally identical transformation. There shouldn't be any visible behavior change. memcg is rather special and will be converted separately. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <paul@paulmenage.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Vivek Goyal <vgoyal@redhat.com>
2012-04-01cgroup: relocate cftype and cgroup_subsys definitions in controllersTejun Heo1-16/+11
blk-cgroup, netprio_cgroup, cls_cgroup and tcp_memcontrol unnecessarily define cftype array and cgroup_subsys structures at the top of the file, which is unconventional and necessiates forward declaration of methods. This patch relocates those below the definitions of the methods and removes the forward declarations. Note that forward declaration of tcp_files[] is added in tcp_memcontrol.c for tcp_init_cgroup(). This will be removed soon by another patch. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-02-02cgroup: remove cgroup_subsys argument from callbacksLi Zefan1-6/+4
The argument is not used at all, and it's not necessary, because a specific callback handler of course knows which subsys it belongs to. Now only ->pupulate() takes this argument, because the handlers of this callback always call cgroup_add_file()/cgroup_add_files(). So we reduce a few lines of code, though the shrinking of object size is minimal. 16 files changed, 113 insertions(+), 162 deletions(-) text data bss dec hex filename 5486240 656987 7039960 13183187 c928d3 vmlinux.o.orig 5486170 656987 7039960 13183117 c9288d vmlinux.o Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2011-07-06net: sched: constify tcf_proto and tc_actionEric Dumazet1-1/+1
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-20net_sched: cleanupsEric Dumazet1-4/+4
Cleanup net/sched code to current CodingStyle and practices. Reduce inline abuse Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-04cls_cgroup: Fix crash on module unloadHerbert Xu1-2/+0
Somewhere along the lines net_cls_subsys_id became a macro when cls_cgroup is built as a module. Not only did it make cls_cgroup completely useless, it also causes it to crash on module unload. This patch fixes this by removing that macro. Thanks to Eric Dumazet for diagnosing this problem. Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-18sched: Fix softirq time accountingVenkatesh Pallipadi1-1/+1
Peter Zijlstra found a bug in the way softirq time is accounted in VIRT_CPU_ACCOUNTING on this thread: http://lkml.indiana.edu/hypermail//linux/kernel/1009.2/01366.html The problem is, softirq processing uses local_bh_disable internally. There is no way, later in the flow, to differentiate between whether softirq is being processed or is it just that bh has been disabled. So, a hardirq when bh is disabled results in time being wrongly accounted as softirq. Looking at the code a bit more, the problem exists in !VIRT_CPU_ACCOUNTING as well. As account_system_time() in normal tick based accouting also uses softirq_count, which will be set even when not in softirq with bh disabled. Peter also suggested solution of using 2*SOFTIRQ_OFFSET as irq count for local_bh_{disable,enable} and using just SOFTIRQ_OFFSET while softirq processing. The patch below does that and adds API in_serving_softirq() which returns whether we are currently processing softirq or not. Also changes one of the usages of softirq_count in net/sched/cls_cgroup.c to in_serving_softirq. Looks like many usages of in_softirq really want in_serving_softirq. Those changes can be made individually on a case by case basis. Signed-off-by: Venkatesh Pallipadi <venki@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1286237003-12406-2-git-send-email-venki@google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-24cls_cgroup: Store classid in struct sockHerbert Xu1-16/+34
Up until now cls_cgroup has relied on fetching the classid out of the current executing thread. This runs into trouble when a packet processing is delayed in which case it may execute out of another thread's context. Furthermore, even when a packet is not delayed we may fail to classify it if soft IRQs have been disabled, because this scenario is indistinguishable from one where a packet unrelated to the current thread is processed by a real soft IRQ. In fact, the current semantics is inherently broken, as a single skb may be constructed out of the writes of two different tasks. A different manifestation of this problem is when the TCP stack transmits in response of an incoming ACK. This is currently unclassified. As we already have a concept of packet ownership for accounting purposes in the skb->sk pointer, this is a natural place to store the classid in a persistent manner. This patch adds the cls_cgroup classid in struct sock, filling up an existing hole on 64-bit :) The value is set at socket creation time. So all sockets created via socket(2) automatically gains the ID of the thread creating it. Whenever another process touches the socket by either reading or writing to it, we will change the socket classid to that of the process if it has a valid (non-zero) classid. For sockets created on inbound connections through accept(2), we inherit the classid of the original listening socket through sk_clone, possibly preceding the actual accept(2) call. In order to minimise risks, I have not made this the authoritative classid. For now it is only used as a backup when we execute with soft IRQs disabled. Once we're completely happy with its semantics we can use it as the sole classid. Footnote: I have rearranged the error path on cls_group module creation. If we didn't do this, then there is a window where someone could create a tc rule using cls_group before the cgroup subsystem has been registered. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
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>
2010-03-23cgroups: net_cls as moduleBen Blum1-9/+27
Allows the net_cls cgroup subsystem to be compiled as a module This patch modifies net/sched/cls_cgroup.c to allow the net_cls subsystem to be optionally compiled as a module instead of builtin. The cgroup_subsys struct is moved around a bit to allow the subsys_id to be either declared as a compile-time constant by the cgroup_subsys.h include in cgroup.h, or, if it's a module, initialized within the struct by cgroup_load_subsys. Signed-off-by: Ben Blum <bblum@andrew.cmu.edu> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-15Merge branch 'master' of ↵David S. Miller1-0/+3
master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/scsi/fcoe/fcoe.c net/core/drop_monitor.c net/core/net-traces.c
2009-06-09cls_cgroup: Fix oops when user send improperly 'tc filter add' requestMinoru Usui1-0/+3
I found a bug in cls_cgroup_change() in cls_cgroup.c. cls_cgroup_change() expected tca[TCA_OPTIONS] was set from user space properly, but tc in iproute2-2.6.29-1 (which I used) didn't set it. In the current source code of tc in git, it set tca[TCA_OPTIONS]. git://git.kernel.org/pub/scm/linux/kernel/git/shemminger/iproute2.git If we always use a newest iproute2 in git when we use cls_cgroup, we don't face this oops probably. But I think, kernel shouldn't panic regardless of use program's behaviour. Signed-off-by: Minoru Usui <usui@mxm.nes.nec.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>