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author | Tejun Heo <tj@kernel.org> | 2012-04-01 12:30:01 -0700 |
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committer | Tejun Heo <tj@kernel.org> | 2012-04-01 12:55:00 -0700 |
commit | 959d851caa48829eb85cb85aa949fd6b4c5d5bc6 (patch) | |
tree | 3ba9c94ec346275fb44c4f0d1cd2537cdff8d811 /kernel/rcu.h | |
parent | a5567932fc926739e29e98487128080f40c61710 (diff) | |
parent | 48ddbe194623ae089cc0576e60363f2d2e85662a (diff) | |
download | op-kernel-dev-959d851caa48829eb85cb85aa949fd6b4c5d5bc6.zip op-kernel-dev-959d851caa48829eb85cb85aa949fd6b4c5d5bc6.tar.gz |
Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged
cgroup/for-3.5 contains the following changes which blk-cgroup needs
to proceed with the on-going cleanup.
* Dynamic addition and removal of cftypes to make config/stat file
handling modular for policies.
* cgroup removal update to not wait for css references to drain to fix
blkcg removal hang caused by cfq caching cfqgs.
Pull in cgroup/for-3.5 into block/for-3.5/core. This causes the
following conflicts in block/blk-cgroup.c.
* 761b3ef50e "cgroup: remove cgroup_subsys argument from callbacks"
conflicts with blkiocg_pre_destroy() addition and blkiocg_attach()
removal. Resolved by removing @subsys from all subsys methods.
* 676f7c8f84 "cgroup: relocate cftype and cgroup_subsys definitions in
controllers" conflicts with ->pre_destroy() and ->attach() updates
and removal of modular config. Resolved by dropping forward
declarations of the methods and applying updates to the relocated
blkio_subsys.
* 4baf6e3325 "cgroup: convert all non-memcg controllers to the new
cftype interface" builds upon the previous item. Resolved by adding
->base_cftypes to the relocated blkio_subsys.
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel/rcu.h')
-rw-r--r-- | kernel/rcu.h | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/kernel/rcu.h b/kernel/rcu.h index aa88baa..8ba99cd 100644 --- a/kernel/rcu.h +++ b/kernel/rcu.h @@ -33,8 +33,27 @@ * Process-level increment to ->dynticks_nesting field. This allows for * architectures that use half-interrupts and half-exceptions from * process context. + * + * DYNTICK_TASK_NEST_MASK defines a field of width DYNTICK_TASK_NEST_WIDTH + * that counts the number of process-based reasons why RCU cannot + * consider the corresponding CPU to be idle, and DYNTICK_TASK_NEST_VALUE + * is the value used to increment or decrement this field. + * + * The rest of the bits could in principle be used to count interrupts, + * but this would mean that a negative-one value in the interrupt + * field could incorrectly zero out the DYNTICK_TASK_NEST_MASK field. + * We therefore provide a two-bit guard field defined by DYNTICK_TASK_MASK + * that is set to DYNTICK_TASK_FLAG upon initial exit from idle. + * The DYNTICK_TASK_EXIT_IDLE value is thus the combined value used upon + * initial exit from idle. */ -#define DYNTICK_TASK_NESTING (LLONG_MAX / 2 - 1) +#define DYNTICK_TASK_NEST_WIDTH 7 +#define DYNTICK_TASK_NEST_VALUE ((LLONG_MAX >> DYNTICK_TASK_NEST_WIDTH) + 1) +#define DYNTICK_TASK_NEST_MASK (LLONG_MAX - DYNTICK_TASK_NEST_VALUE + 1) +#define DYNTICK_TASK_FLAG ((DYNTICK_TASK_NEST_VALUE / 8) * 2) +#define DYNTICK_TASK_MASK ((DYNTICK_TASK_NEST_VALUE / 8) * 3) +#define DYNTICK_TASK_EXIT_IDLE (DYNTICK_TASK_NEST_VALUE + \ + DYNTICK_TASK_FLAG) /* * debug_rcu_head_queue()/debug_rcu_head_unqueue() are used internally @@ -50,7 +69,6 @@ extern struct debug_obj_descr rcuhead_debug_descr; static inline void debug_rcu_head_queue(struct rcu_head *head) { - WARN_ON_ONCE((unsigned long)head & 0x3); debug_object_activate(head, &rcuhead_debug_descr); debug_object_active_state(head, &rcuhead_debug_descr, STATE_RCU_HEAD_READY, @@ -76,16 +94,18 @@ static inline void debug_rcu_head_unqueue(struct rcu_head *head) extern void kfree(const void *); -static inline void __rcu_reclaim(char *rn, struct rcu_head *head) +static inline bool __rcu_reclaim(char *rn, struct rcu_head *head) { unsigned long offset = (unsigned long)head->func; if (__is_kfree_rcu_offset(offset)) { RCU_TRACE(trace_rcu_invoke_kfree_callback(rn, head, offset)); kfree((void *)head - offset); + return 1; } else { RCU_TRACE(trace_rcu_invoke_callback(rn, head)); head->func(head); + return 0; } } |