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| author | Paul E. McKenney <paulmck@kernel.org> | 2022-05-16 17:56:16 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-06-20 09:22:28 -0700 |
| commit | 434c9eefb959c36331a93617ea95df903469b99f (patch) | |
| tree | 4ca98f3c279c7595a906f3a8b9f8e315befd418c /kernel | |
| parent | f90f19da88bfe32dd1fdfd104de4c0526a3be701 (diff) | |
| download | linux-434c9eefb959c36331a93617ea95df903469b99f.tar.gz | |
rcu-tasks: Add data structures for lightweight grace periods
This commit adds fields to task_struct and to rcu_tasks_percpu that will be used to avoid the task-list scan for RCU Tasks Trace grace periods, and also initializes these fields. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <kafai@fb.com> Cc: KP Singh <kpsingh@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/fork.c | 1 | ||||
| -rw-r--r-- | kernel/rcu/tasks.h | 4 |
2 files changed, 5 insertions, 0 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 9d44f2d46c69..1950eb870244 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1814,6 +1814,7 @@ static inline void rcu_copy_process(struct task_struct *p) p->trc_reader_nesting = 0; p->trc_reader_special.s = 0; INIT_LIST_HEAD(&p->trc_holdout_list); + INIT_LIST_HEAD(&p->trc_blkd_node); #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ } diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 64eb4d7b142e..fd4508af055e 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -29,6 +29,7 @@ typedef void (*postgp_func_t)(struct rcu_tasks *rtp); * @rtp_work: Work queue for invoking callbacks. * @rtp_irq_work: IRQ work queue for deferred wakeups. * @barrier_q_head: RCU callback for barrier operation. + * @rtp_blkd_tasks: List of tasks blocked as readers. * @cpu: CPU number corresponding to this entry. * @rtpp: Pointer to the rcu_tasks structure. */ @@ -40,6 +41,7 @@ struct rcu_tasks_percpu { struct work_struct rtp_work; struct irq_work rtp_irq_work; struct rcu_head barrier_q_head; + struct list_head rtp_blkd_tasks; int cpu; struct rcu_tasks *rtpp; }; @@ -256,6 +258,8 @@ static void cblist_init_generic(struct rcu_tasks *rtp) INIT_WORK(&rtpcp->rtp_work, rcu_tasks_invoke_cbs_wq); rtpcp->cpu = cpu; rtpcp->rtpp = rtp; + if (!rtpcp->rtp_blkd_tasks.next) + INIT_LIST_HEAD(&rtpcp->rtp_blkd_tasks); raw_spin_unlock_rcu_node(rtpcp); // irqs remain disabled. } raw_spin_unlock_irqrestore(&rtp->cbs_gbl_lock, flags); |