linux-kernel - [PATCH] arm64: topology: Drop the useless update to per-cpu cycles

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Date:   Thu, 10 Dec 2020 11:17:40 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>,
        Sudeep Holla <sudeep.holla@....com>,
        Ionela Voinescu <ionela.voinescu@....com>
Cc:     Viresh Kumar <viresh.kumar@...aro.org>,
        Vincent Guittot <vincent.guittot@...aro.org>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH] arm64: topology: Drop the useless update to per-cpu cycles

The previous call to update_freq_counters_refs() has already updated the
per-cpu variables, don't overwrite them with the same value again.

Fixes: 4b9cf23c179a ("arm64: wrap and generalise counter read functions")
Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
 arch/arm64/kernel/topology.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index c8308befdb1e..f6faa697e83e 100644
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -314,7 +314,7 @@ void topology_scale_freq_tick(void)
 
 	if (unlikely(core_cnt <= prev_core_cnt ||
 		     const_cnt <= prev_const_cnt))
-		goto store_and_exit;
+		return;
 
 	/*
 	 *	    /\core    arch_max_freq_scale
@@ -331,10 +331,6 @@ void topology_scale_freq_tick(void)
 
 	scale = min_t(unsigned long, scale, SCHED_CAPACITY_SCALE);
 	this_cpu_write(freq_scale, (unsigned long)scale);
-
-store_and_exit:
-	this_cpu_write(arch_core_cycles_prev, core_cnt);
-	this_cpu_write(arch_const_cycles_prev, const_cnt);
 }
 
 #ifdef CONFIG_ACPI_CPPC_LIB
-- 
2.25.0.rc1.19.g042ed3e048af