linux-kernel - [PATCH v2 2/3] MIPS: smp: Remove tick_broadcast

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Message-Id: <20191216213125.9536-3-peterx@redhat.com>
Date:   Mon, 16 Dec 2019 16:31:24 -0500
From:   Peter Xu <peterx@...hat.com>
To:     linux-kernel@...r.kernel.org
Cc:     Thomas Gleixner <tglx@...utronix.de>,
        Juri Lelli <juri.lelli@...hat.com>, peterx@...hat.com,
        Marcelo Tosatti <mtosatti@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>
Subject: [PATCH v2 2/3] MIPS: smp: Remove tick_broadcast_count

Now smp_call_function_single_async() provides the protection that
we'll return with -EBUSY if the csd object is still pending, then we
don't need the tick_broadcast_count counter any more.

Signed-off-by: Peter Xu <peterx@...hat.com>
---
 arch/mips/kernel/smp.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index f510c00bda88..0678901c214d 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -696,21 +696,16 @@ EXPORT_SYMBOL(flush_tlb_one);
 
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 
-static DEFINE_PER_CPU(atomic_t, tick_broadcast_count);
 static DEFINE_PER_CPU(call_single_data_t, tick_broadcast_csd);
 
 void tick_broadcast(const struct cpumask *mask)
 {
-	atomic_t *count;
 	call_single_data_t *csd;
 	int cpu;
 
 	for_each_cpu(cpu, mask) {
-		count = &per_cpu(tick_broadcast_count, cpu);
 		csd = &per_cpu(tick_broadcast_csd, cpu);
-
-		if (atomic_inc_return(count) == 1)
-			smp_call_function_single_async(cpu, csd);
+		smp_call_function_single_async(cpu, csd);
 	}
 }
 
@@ -718,7 +713,6 @@ static void tick_broadcast_callee(void *info)
 {
 	int cpu = smp_processor_id();
 	tick_receive_broadcast();
-	atomic_set(&per_cpu(tick_broadcast_count, cpu), 0);
 }
 
 static int __init tick_broadcast_init(void)
-- 
2.23.0