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Date:   Fri, 16 Aug 2019 10:25:29 -0700
From:   "Paul E. McKenney" <paulmck@linux.ibm.com>
To:     "Joel Fernandes (Google)" <joel@joelfernandes.org>
Cc:     linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
        frederic@kernel.org
Subject: Re: [PATCH -rcu dev 1/3] rcu/tree: tick_dep_set/clear_cpu should
 accept bits instead of masks
Reply-To: paulmck@linux.ibm.com
References: <20190816025311.241257-1-joel@joelfernandes.org>
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On Thu, Aug 15, 2019 at 10:53:09PM -0400, Joel Fernandes (Google) wrote:
> This commit fixes the issue.
> 
> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>

And I am squashing these into their respective commits with attribution.
Good eyes, thank you very much!!!

							Thanx, Paul

> ---
>  kernel/rcu/tree.c | 29 +++++++++++++++++------------
>  1 file changed, 17 insertions(+), 12 deletions(-)
> 
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index 0512de9ead20..322b1b57967c 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -829,7 +829,7 @@ static __always_inline void rcu_nmi_enter_common(bool irq)
>  		   !rdp->dynticks_nmi_nesting &&
>  		   rdp->rcu_urgent_qs && !rdp->rcu_forced_tick) {
>  		rdp->rcu_forced_tick = true;
> -		tick_dep_set_cpu(rdp->cpu, TICK_DEP_MASK_RCU);
> +		tick_dep_set_cpu(rdp->cpu, TICK_DEP_BIT_RCU);
>  	}
>  	trace_rcu_dyntick(incby == 1 ? TPS("Endirq") : TPS("++="),
>  			  rdp->dynticks_nmi_nesting,
> @@ -898,7 +898,7 @@ void rcu_irq_enter_irqson(void)
>  void rcu_disable_tick_upon_qs(struct rcu_data *rdp)
>  {
>  	if (tick_nohz_full_cpu(rdp->cpu) && rdp->rcu_forced_tick) {
> -		tick_dep_clear_cpu(rdp->cpu, TICK_DEP_MASK_RCU);
> +		tick_dep_clear_cpu(rdp->cpu, TICK_DEP_BIT_RCU);
>  		rdp->rcu_forced_tick = false;
>  	}
>  }
> @@ -2123,8 +2123,9 @@ int rcutree_dead_cpu(unsigned int cpu)
>  	do_nocb_deferred_wakeup(per_cpu_ptr(&rcu_data, cpu));
>  
>  	// Stop-machine done, so allow nohz_full to disable tick.
> -	for_each_online_cpu(c)
> -		tick_dep_clear_cpu(c, TICK_DEP_MASK_RCU);
> +	for_each_online_cpu(c) {
> +		tick_dep_clear_cpu(c, TICK_DEP_BIT_RCU);
> +	}
>  	return 0;
>  }
>  
> @@ -2175,8 +2176,9 @@ static void rcu_do_batch(struct rcu_data *rdp)
>  	rcu_nocb_unlock_irqrestore(rdp, flags);
>  
>  	/* Invoke callbacks. */
> -	if (IS_ENABLED(CONFIG_NO_HZ_FULL))
> -		tick_dep_set_task(current, TICK_DEP_MASK_RCU);
> +	if (IS_ENABLED(CONFIG_NO_HZ_FULL)) {
> +		tick_dep_set_task(current, TICK_DEP_BIT_RCU);
> +	}
>  	rhp = rcu_cblist_dequeue(&rcl);
>  	for (; rhp; rhp = rcu_cblist_dequeue(&rcl)) {
>  		debug_rcu_head_unqueue(rhp);
> @@ -2243,8 +2245,9 @@ static void rcu_do_batch(struct rcu_data *rdp)
>  	/* Re-invoke RCU core processing if there are callbacks remaining. */
>  	if (!offloaded && rcu_segcblist_ready_cbs(&rdp->cblist))
>  		invoke_rcu_core();
> -	if (IS_ENABLED(CONFIG_NO_HZ_FULL))
> -		tick_dep_clear_task(current, TICK_DEP_MASK_RCU);
> +	if (IS_ENABLED(CONFIG_NO_HZ_FULL)) {
> +		tick_dep_clear_task(current, TICK_DEP_BIT_RCU);
> +	}
>  }
>  
>  /*
> @@ -3118,8 +3121,9 @@ int rcutree_online_cpu(unsigned int cpu)
>  	rcutree_affinity_setting(cpu, -1);
>  
>  	// Stop-machine done, so allow nohz_full to disable tick.
> -	for_each_online_cpu(c)
> -		tick_dep_clear_cpu(c, TICK_DEP_MASK_RCU);
> +	for_each_online_cpu(c) {
> +		tick_dep_clear_cpu(c, TICK_DEP_BIT_RCU);
> +	}
>  	return 0;
>  }
>  
> @@ -3143,8 +3147,9 @@ int rcutree_offline_cpu(unsigned int cpu)
>  	rcutree_affinity_setting(cpu, cpu);
>  
>  	// nohz_full CPUs need the tick for stop-machine to work quickly
> -	for_each_online_cpu(c)
> -		tick_dep_set_cpu(c, TICK_DEP_MASK_RCU);
> +	for_each_online_cpu(c) {
> +		tick_dep_set_cpu(c, TICK_DEP_BIT_RCU);
> +	}
>  	return 0;
>  }
>  
> -- 
> 2.23.0.rc1.153.gdeed80330f-goog
>