diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-04 15:54:04 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-04 15:54:04 -0700 |
commit | 4057adafb395204af4ff93f3669ecb49eb45b3cf (patch) | |
tree | d6b0abf50ec5cd658fe958f90941c0192486549c /kernel/rcu/tree.h | |
parent | Merge tag 'm68k-for-v4.18-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k (diff) | |
parent | Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu (diff) | |
download | linux-dev-4057adafb395204af4ff93f3669ecb49eb45b3cf.tar.xz linux-dev-4057adafb395204af4ff93f3669ecb49eb45b3cf.zip |
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
- updates to the handling of expedited grace periods
- updates to reduce lock contention in the rcu_node combining tree
[ These are in preparation for the consolidation of RCU-bh,
RCU-preempt, and RCU-sched into a single flavor, which was
requested by Linus in response to a security flaw whose root cause
included confusion between the multiple flavors of RCU ]
- torture-test updates that save their users some time and effort
- miscellaneous fixes
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
rcu/x86: Provide early rcu_cpu_starting() callback
torture: Make kvm-find-errors.sh find build warnings
rcutorture: Abbreviate kvm.sh summary lines
rcutorture: Print end-of-test state in kvm.sh summary
rcutorture: Print end-of-test state
torture: Fold parse-torture.sh into parse-console.sh
torture: Add a script to edit output from failed runs
rcu: Update list of rcu_future_grace_period() trace events
rcu: Drop early GP request check from rcu_gp_kthread()
rcu: Simplify and inline cpu_needs_another_gp()
rcu: The rcu_gp_cleanup() function does not need cpu_needs_another_gp()
rcu: Make rcu_start_this_gp() check for out-of-range requests
rcu: Add funnel locking to rcu_start_this_gp()
rcu: Make rcu_start_future_gp() caller select grace period
rcu: Inline rcu_start_gp_advanced() into rcu_start_future_gp()
rcu: Clear request other than RCU_GP_FLAG_INIT at GP end
rcu: Cleanup, don't put ->completed into an int
rcu: Switch __rcu_process_callbacks() to rcu_accelerate_cbs()
rcu: Avoid __call_rcu_core() root rcu_node ->lock acquisition
rcu: Make rcu_migrate_callbacks wake GP kthread when needed
...
Diffstat (limited to 'kernel/rcu/tree.h')
-rw-r--r-- | kernel/rcu/tree.h | 36 |
1 files changed, 27 insertions, 9 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index f491ab4f2e8e..78e051dffc5b 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -58,6 +58,14 @@ struct rcu_dynticks { #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ }; +/* Communicate arguments to a workqueue handler. */ +struct rcu_exp_work { + smp_call_func_t rew_func; + struct rcu_state *rew_rsp; + unsigned long rew_s; + struct work_struct rew_work; +}; + /* RCU's kthread states for tracing. */ #define RCU_KTHREAD_STOPPED 0 #define RCU_KTHREAD_RUNNING 1 @@ -150,15 +158,32 @@ struct rcu_node { struct swait_queue_head nocb_gp_wq[2]; /* Place for rcu_nocb_kthread() to wait GP. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ - int need_future_gp[2]; - /* Counts of upcoming no-CB GP requests. */ + u8 need_future_gp[4]; /* Counts of upcoming GP requests. */ raw_spinlock_t fqslock ____cacheline_internodealigned_in_smp; spinlock_t exp_lock ____cacheline_internodealigned_in_smp; unsigned long exp_seq_rq; wait_queue_head_t exp_wq[4]; + struct rcu_exp_work rew; + bool exp_need_flush; /* Need to flush workitem? */ } ____cacheline_internodealigned_in_smp; +/* Accessors for ->need_future_gp[] array. */ +#define need_future_gp_mask() \ + (ARRAY_SIZE(((struct rcu_node *)NULL)->need_future_gp) - 1) +#define need_future_gp_element(rnp, c) \ + ((rnp)->need_future_gp[(c) & need_future_gp_mask()]) +#define need_any_future_gp(rnp) \ +({ \ + int __i; \ + bool __nonzero = false; \ + \ + for (__i = 0; __i < ARRAY_SIZE((rnp)->need_future_gp); __i++) \ + __nonzero = __nonzero || \ + READ_ONCE((rnp)->need_future_gp[__i]); \ + __nonzero; \ +}) + /* * Bitmasks in an rcu_node cover the interval [grplo, grphi] of CPU IDs, and * are indexed relative to this interval rather than the global CPU ID space. @@ -224,10 +249,6 @@ struct rcu_data { #ifdef CONFIG_RCU_FAST_NO_HZ struct rcu_head oom_head; #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ - atomic_long_t exp_workdone0; /* # done by workqueue. */ - atomic_long_t exp_workdone1; /* # done by others #1. */ - atomic_long_t exp_workdone2; /* # done by others #2. */ - atomic_long_t exp_workdone3; /* # done by others #3. */ int exp_dynticks_snap; /* Double-check need for IPI. */ /* 6) Callback offloading. */ @@ -408,7 +429,6 @@ extern struct rcu_state rcu_preempt_state; #endif /* #ifdef CONFIG_PREEMPT_RCU */ int rcu_dynticks_snap(struct rcu_dynticks *rdtp); -bool rcu_eqs_special_set(int cpu); #ifdef CONFIG_RCU_BOOST DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status); @@ -438,7 +458,6 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); static void invoke_rcu_callbacks_kthread(void); static bool rcu_is_callbacks_kthread(void); #ifdef CONFIG_RCU_BOOST -static void rcu_preempt_do_callbacks(void); static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp); #endif /* #ifdef CONFIG_RCU_BOOST */ @@ -454,7 +473,6 @@ static void print_cpu_stall_info_end(void); static void zero_cpu_stall_ticks(struct rcu_data *rdp); static void increment_cpu_stall_ticks(void); static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu); -static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq); static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp); static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq); static void rcu_init_one_nocb(struct rcu_node *rnp); |