linux-kernel - [Patch 1/6] cpufreq: use correct unit when verify cur freq

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Date:   Tue, 18 Apr 2023 17:04:54 +0530
From:   Sumit Gupta <sumitg@...dia.com>
To:     <viresh.kumar@...aro.org>, <rafael@...nel.org>,
        <ionela.voinescu@....com>, <mark.rutland@....com>,
        <sudeep.holla@....com>, <lpieralisi@...nel.org>,
        <catalin.marinas@....com>, <will@...nel.org>
CC:     <linux-pm@...r.kernel.org>, <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <linux-tegra@...r.kernel.org>,
        <treding@...dia.com>, <jonathanh@...dia.com>, <vsethi@...dia.com>,
        <sdonthineni@...dia.com>, <sanjayc@...dia.com>,
        <ksitaraman@...dia.com>, <bbasu@...dia.com>, <sumitg@...dia.com>
Subject: [Patch 1/6] cpufreq: use correct unit when verify cur freq

From: Sanjay Chandrashekara <sanjayc@...dia.com>

cpufreq_verify_current_freq checks if the frequency returned by
the hardware has a slight delta with the valid frequency value
last set and returns "policy->cur" if the delta is within "1 MHz".
In the comparison, "policy->cur" is in "kHz" but it's compared
against HZ_PER_MHZ. So, the comparison range becomes "1 GHz".
Fix this by comparing against KHZ_PER_MHZ instead of HZ_PER_MHZ.

Fixes: f55ae08c8987 ("cpufreq: Avoid unnecessary frequency updates due to mismatch")
Signed-off-by: Sanjay Chandrashekara <sanjayc@...dia.com>
[ sumit gupta: Commit message update ]
Signed-off-by: Sumit Gupta <sumitg@...dia.com>
---
 drivers/cpufreq/cpufreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 8b0509f89f1b..6b52ebe5a890 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1732,7 +1732,7 @@ static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, b
 		 * MHz. In such cases it is better to avoid getting into
 		 * unnecessary frequency updates.
 		 */
-		if (abs(policy->cur - new_freq) < HZ_PER_MHZ)
+		if (abs(policy->cur - new_freq) < KHZ_PER_MHZ)
 			return policy->cur;
 
 		cpufreq_out_of_sync(policy, new_freq);
-- 
2.17.1