1. 08 Dec, 2015 1 commit
    • Tejun Heo's avatar
      net: wrap sock->sk_cgrp_prioidx and ->sk_classid inside a struct · 2a56a1fe
      Tejun Heo authored
      Introduce sock->sk_cgrp_data which is a struct sock_cgroup_data.
      ->sk_cgroup_prioidx and ->sk_classid are moved into it.  The struct
      and its accessors are defined in cgroup-defs.h.  This is to prepare
      for overloading the fields with a cgroup pointer.
      
      This patch mostly performs equivalent conversions but the followings
      are noteworthy.
      
      * Equality test before updating classid is removed from
        sock_update_classid().  This shouldn't make any noticeable
        difference and a similar test will be implemented on the helper side
        later.
      
      * sock_update_netprioidx() now takes struct sock_cgroup_data and can
        be moved to netprio_cgroup.h without causing include dependency
        loop.  Moved.
      
      * The dummy version of sock_update_netprioidx() converted to a static
        inline function while at it.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2a56a1fe
  2. 08 Feb, 2014 2 commits
    • Tejun Heo's avatar
      cgroup: clean up cgroup_subsys names and initialization · 073219e9
      Tejun Heo authored
      cgroup_subsys is a bit messier than it needs to be.
      
      * The name of a subsys can be different from its internal identifier
        defined in cgroup_subsys.h.  Most subsystems use the matching name
        but three - cpu, memory and perf_event - use different ones.
      
      * cgroup_subsys_id enums are postfixed with _subsys_id and each
        cgroup_subsys is postfixed with _subsys.  cgroup.h is widely
        included throughout various subsystems, it doesn't and shouldn't
        have claim on such generic names which don't have any qualifier
        indicating that they belong to cgroup.
      
      * cgroup_subsys->subsys_id should always equal the matching
        cgroup_subsys_id enum; however, we require each controller to
        initialize it and then BUG if they don't match, which is a bit
        silly.
      
      This patch cleans up cgroup_subsys names and initialization by doing
      the followings.
      
      * cgroup_subsys_id enums are now postfixed with _cgrp_id, and each
        cgroup_subsys with _cgrp_subsys.
      
      * With the above, renaming subsys identifiers to match the userland
        visible names doesn't cause any naming conflicts.  All non-matching
        identifiers are renamed to match the official names.
      
        cpu_cgroup -> cpu
        mem_cgroup -> memory
        perf -> perf_event
      
      * controllers no longer need to initialize ->subsys_id and ->name.
        They're generated in cgroup core and set automatically during boot.
      
      * Redundant cgroup_subsys declarations removed.
      
      * While updating BUG_ON()s in cgroup_init_early(), convert them to
        WARN()s.  BUGging that early during boot is stupid - the kernel
        can't print anything, even through serial console and the trap
        handler doesn't even link stack frame properly for back-tracing.
      
      This patch doesn't introduce any behavior changes.
      
      v2: Rebased on top of fe1217c4 ("net: net_cls: move cgroupfs
          classid handling into core").
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Acked-by: default avatar"David S. Miller" <davem@davemloft.net>
      Acked-by: default avatar"Rafael J. Wysocki" <rjw@rjwysocki.net>
      Acked-by: default avatarMichal Hocko <mhocko@suse.cz>
      Acked-by: default avatarPeter Zijlstra <peterz@infradead.org>
      Acked-by: default avatarAristeu Rozanski <aris@redhat.com>
      Acked-by: default avatarIngo Molnar <mingo@redhat.com>
      Acked-by: default avatarLi Zefan <lizefan@huawei.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Balbir Singh <bsingharora@gmail.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Serge E. Hallyn <serue@us.ibm.com>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: Thomas Graf <tgraf@suug.ch>
      073219e9
    • Tejun Heo's avatar
      cgroup: make CONFIG_CGROUP_NET_PRIO bool and drop unnecessary init_netclassid_cgroup() · af636337
      Tejun Heo authored
      net_prio is the only cgroup which is allowed to be built as a module.
      The savings from allowing one controller to be built as a module are
      tiny especially given that cgroup module support itself adds quite a
      bit of complexity.
      
      Given that none of other controllers has much chance of being made a
      module and that we're unlikely to add new modular controllers, the
      added complexity is simply not justifiable.
      
      As a first step to drop cgroup module support, this patch changes the
      config option to bool from tristate and drops module related code from
      it.
      
      Also, while an earlier commit fe1217c4 ("net: net_cls: move
      cgroupfs classid handling into core") dropped module support from
      net_cls cgroup, it retained a call to cgroup_load_subsys(), which is
      noop for built-in controllers.  Drop it along with
      init_netclassid_cgroup().
      
      v2: Removed modular version of task_netprioidx() in
          include/net/netprio_cgroup.h as suggested by Li Zefan.
      
      v3: Rebased on top of fe1217c4 ("net: net_cls: move cgroupfs
          classid handling into core").  net_cls cgroup part is mostly
          dropped except for removal of init_netclassid_cgroup().
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Acked-by: default avatar"David S. Miller" <davem@davemloft.net>
      Acked-by: default avatarLi Zefan <lizefan@huawei.com>
      Cc: Thomas Graf <tgraf@suug.ch>
      af636337
  3. 03 Jan, 2014 1 commit
  4. 08 Aug, 2013 2 commits
  5. 31 Jul, 2013 1 commit
  6. 09 Apr, 2013 1 commit
  7. 22 Nov, 2012 1 commit
  8. 14 Sep, 2012 2 commits
    • Daniel Wagner's avatar
      cgroup: Assign subsystem IDs during compile time · 8a8e04df
      Daniel Wagner authored
      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 f8451725
        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: default avatarDaniel Wagner <daniel.wagner@bmw-carit.de>
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarLi Zefan <lizefan@huawei.com>
      Acked-by: default avatarNeil 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
      8a8e04df
    • Daniel Wagner's avatar
      cgroup: net_prio: Do not define task_netpioidx() when not selected · 51e4e7fa
      Daniel Wagner authored
      task_netprioidx() should not be defined in case the configuration is
      CONFIG_NETPRIO_CGROUP=n. The reason is that in a following patch the
      net_prio_subsys_id will only be defined if CONFIG_NETPRIO_CGROUP!=n.
      When net_prio is not built at all any callee should only get an empty
      task_netprioidx() without any references to net_prio_subsys_id.
      Signed-off-by: default avatarDaniel Wagner <daniel.wagner@bmw-carit.de>
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarLi Zefan <lizefan@huawei.com>
      Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Cc: Gao feng <gaofeng@cn.fujitsu.com>
      Cc: Jamal Hadi Salim <jhs@mojatatu.com>
      Cc: John Fastabend <john.r.fastabend@intel.com>
      Cc: netdev@vger.kernel.org
      Cc: cgroups@vger.kernel.org
      51e4e7fa
  9. 22 Jul, 2012 1 commit
    • John Fastabend's avatar
      net: netprio_cgroup: rework update socket logic · 406a3c63
      John Fastabend authored
      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.
      Signed-off-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
      Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      406a3c63
  10. 10 Feb, 2012 1 commit
  11. 24 Jan, 2012 1 commit
  12. 23 Nov, 2011 1 commit
  13. 22 Nov, 2011 1 commit
    • Neil Horman's avatar
      net: add network priority cgroup infrastructure (v4) · 5bc1421e
      Neil Horman authored
      This patch adds in the infrastructure code to create the network priority
      cgroup.  The cgroup, in addition to the standard processes file creates two
      control files:
      
      1) prioidx - This is a read-only file that exports the index of this cgroup.
      This is a value that is both arbitrary and unique to a cgroup in this subsystem,
      and is used to index the per-device priority map
      
      2) priomap - This is a writeable file.  On read it reports a table of 2-tuples
      <name:priority> where name is the name of a network interface and priority is
      indicates the priority assigned to frames egresessing on the named interface and
      originating from a pid in this cgroup
      
      This cgroup allows for skb priority to be set prior to a root qdisc getting
      selected. This is benenficial for DCB enabled systems, in that it allows for any
      application to use dcb configured priorities so without application modification
      Signed-off-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Signed-off-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
      CC: Robert Love <robert.w.love@intel.com>
      CC: "David S. Miller" <davem@davemloft.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      5bc1421e