linux-kernel - [PATCH v5 3/4] PM / devfreq: passive: Reduce duplicate code when passive

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220517092108.31680-4-cw00.choi@samsung.com>
Date:   Tue, 17 May 2022 18:21:07 +0900
From:   Chanwoo Choi <cw00.choi@...sung.com>
To:     linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     johnson.wang@...iatek.com, mka@...omium.org, wenst@...omium.org,
        jia-wei.chang@...iatek.com, andrew-sh.cheng@...iatek.com,
        hsinyi@...omium.org, m.szyprowski@...sung.com,
        saravanak@...gle.com, cw00.choi@...sung.com,
        myungjoo.ham@...sung.com, kyungmin.park@...sung.com
Subject: [PATCH v5 3/4] PM / devfreq: passive: Reduce duplicate code when
 passive_devfreq case

In order to keep the consistent coding style between passive_devfreq
and passive_cpufreq, use common code for handling required opp property.
Also remove the unneed conditional statement and unify the comment
of both passive_devfreq and passive_cpufreq when getting the target frequency.

Tested-by: Chen-Yu Tsai <wenst@...omium.org>
Tested-by: Johnson Wang <johnson.wang@...iatek.com>
Signed-off-by: Chanwoo Choi <cw00.choi@...sung.com>
---
 drivers/devfreq/governor_passive.c | 66 ++++--------------------------
 1 file changed, 8 insertions(+), 58 deletions(-)

diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 7f30088b500b..ffcce613a48c 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -93,65 +93,16 @@ static int get_target_freq_with_devfreq(struct devfreq *devfreq,
 			= (struct devfreq_passive_data *)devfreq->data;
 	struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
 	unsigned long child_freq = ULONG_MAX;
-	struct dev_pm_opp *opp, *p_opp;
 	int i, count;
 
-	/*
-	 * If the devfreq device with passive governor has the specific method
-	 * to determine the next frequency, should use the get_target_freq()
-	 * of struct devfreq_passive_data.
-	 */
-	if (p_data->get_target_freq)
-		return p_data->get_target_freq(devfreq, freq);
+	/* Get target freq via required opps */
+	child_freq = get_target_freq_by_required_opp(parent_devfreq->dev.parent,
+						parent_devfreq->opp_table,
+						devfreq->opp_table, freq);
+	if (child_freq)
+		goto out;
 
-	/*
-	 * If the parent and passive devfreq device uses the OPP table,
-	 * get the next frequency by using the OPP table.
-	 */
-
-	/*
-	 * - parent devfreq device uses the governors except for passive.
-	 * - passive devfreq device uses the passive governor.
-	 *
-	 * Each devfreq has the OPP table. After deciding the new frequency
-	 * from the governor of parent devfreq device, the passive governor
-	 * need to get the index of new frequency on OPP table of parent
-	 * device. And then the index is used for getting the suitable
-	 * new frequency for passive devfreq device.
-	 */
-	if (!devfreq->profile || !devfreq->profile->freq_table
-		|| devfreq->profile->max_state <= 0)
-		return -EINVAL;
-
-	/*
-	 * The passive governor have to get the correct frequency from OPP
-	 * list of parent device. Because in this case, *freq is temporary
-	 * value which is decided by ondemand governor.
-	 */
-	if (devfreq->opp_table && parent_devfreq->opp_table) {
-		p_opp = devfreq_recommended_opp(parent_devfreq->dev.parent,
-						freq, 0);
-		if (IS_ERR(p_opp))
-			return PTR_ERR(p_opp);
-
-		opp = dev_pm_opp_xlate_required_opp(parent_devfreq->opp_table,
-						    devfreq->opp_table, p_opp);
-		dev_pm_opp_put(p_opp);
-
-		if (IS_ERR(opp))
-			goto no_required_opp;
-
-		*freq = dev_pm_opp_get_freq(opp);
-		dev_pm_opp_put(opp);
-
-		return 0;
-	}
-
-no_required_opp:
-	/*
-	 * Get the OPP table's index of decided frequency by governor
-	 * of parent device.
-	 */
+	/* Use interpolation if required opps is not available */
 	for (i = 0; i < parent_devfreq->profile->max_state; i++)
 		if (parent_devfreq->profile->freq_table[i] == *freq)
 			break;
@@ -159,7 +110,6 @@ static int get_target_freq_with_devfreq(struct devfreq *devfreq,
 	if (i == parent_devfreq->profile->max_state)
 		return -EINVAL;
 
-	/* Get the suitable frequency by using index of parent device. */
 	if (i < devfreq->profile->max_state) {
 		child_freq = devfreq->profile->freq_table[i];
 	} else {
@@ -167,7 +117,7 @@ static int get_target_freq_with_devfreq(struct devfreq *devfreq,
 		child_freq = devfreq->profile->freq_table[count - 1];
 	}
 
-	/* Return the suitable frequency for passive device. */
+out:
 	*freq = child_freq;
 
 	return 0;
-- 
2.17.1