From: Leonard Crestez <leonard.crestez@nxp.com>
To: Chanwoo Choi <cw00.choi@samsung.com>,
MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: "Kyungmin Park" <kyungmin.park@samsung.com>,
"Rafael J. Wysocki" <rjw@rjwysocki.net>,
"Matthias Kaehlcke" <mka@chromium.org>,
"Artur Świgoń" <a.swigon@partner.samsung.com>,
"Georgi Djakov" <georgi.djakov@linaro.org>,
"Viresh Kumar" <viresh.kumar@linaro.org>,
linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-imx@nxp.com
Subject: [PATCH 5/5] PM / devfreq: Don't take lock in devfreq_add_device
Date: Thu, 14 Nov 2019 01:21:35 +0200 [thread overview]
Message-ID: <683876312e5657ad5405f826d5ab8f09d521883d.1573686315.git.leonard.crestez@nxp.com> (raw)
In-Reply-To: <cover.1573686315.git.leonard.crestez@nxp.com>
In-Reply-To: <cover.1573686315.git.leonard.crestez@nxp.com>
A device usually doesn't need to lock itself during initialization
because it is not yet reachable from other threads.
This simplifies the code and helps avoid recursive lock warnings.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
---
drivers/devfreq/devfreq.c | 13 +------------
1 file changed, 1 insertion(+), 12 deletions(-)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2a035374ae74..e1ce57902391 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -684,11 +684,10 @@ struct devfreq *devfreq_add_device(struct device *dev,
err = -ENOMEM;
goto err_out;
}
mutex_init(&devfreq->lock);
- mutex_lock(&devfreq->lock);
devfreq->dev.parent = dev;
devfreq->dev.class = devfreq_class;
devfreq->dev.release = devfreq_dev_release;
device_initialize(&devfreq->dev);
INIT_LIST_HEAD(&devfreq->node);
@@ -698,28 +697,24 @@ struct devfreq *devfreq_add_device(struct device *dev,
devfreq->last_status.current_frequency = profile->initial_freq;
devfreq->data = data;
devfreq->nb.notifier_call = devfreq_notifier_call;
if (!devfreq->profile->max_state && !devfreq->profile->freq_table) {
- mutex_unlock(&devfreq->lock);
err = set_freq_table(devfreq);
if (err < 0)
goto err_dev;
- mutex_lock(&devfreq->lock);
}
devfreq->scaling_min_freq = find_available_min_freq(devfreq);
if (!devfreq->scaling_min_freq) {
- mutex_unlock(&devfreq->lock);
err = -EINVAL;
goto err_dev;
}
devfreq->min_freq = devfreq->scaling_min_freq;
devfreq->scaling_max_freq = find_available_max_freq(devfreq);
if (!devfreq->scaling_max_freq) {
- mutex_unlock(&devfreq->lock);
err = -EINVAL;
goto err_dev;
}
devfreq->max_freq = devfreq->scaling_max_freq;
@@ -730,21 +725,19 @@ struct devfreq *devfreq_add_device(struct device *dev,
array3_size(sizeof(unsigned int),
devfreq->profile->max_state,
devfreq->profile->max_state),
GFP_KERNEL);
if (!devfreq->trans_table) {
- mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_dev;
}
devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
devfreq->profile->max_state,
sizeof(unsigned long),
GFP_KERNEL);
if (!devfreq->time_in_state) {
- mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_dev;
}
devfreq->last_stat_updated = jiffies;
@@ -752,16 +745,12 @@ struct devfreq *devfreq_add_device(struct device *dev,
srcu_init_notifier_head(&devfreq->transition_notifier_list);
dev_set_name(&devfreq->dev, "devfreq%d",
atomic_inc_return(&devfreq_no));
err = device_add(&devfreq->dev);
- if (err) {
- mutex_unlock(&devfreq->lock);
+ if (err)
goto err_dev;
- }
-
- mutex_unlock(&devfreq->lock);
mutex_lock(&devfreq_list_lock);
governor = try_then_request_governor(devfreq->governor_name);
if (IS_ERR(governor)) {
--
2.17.1
prev parent reply other threads:[~2019-11-13 23:21 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-13 23:21 [PATCH 0/5] PM / devfreq: Don't take lock in devfreq_add_device Leonard Crestez
2019-11-13 23:21 ` [PATCH 1/5] PM / devfreq: Don't fail devfreq_dev_release if not in list Leonard Crestez
2019-12-02 1:07 ` Chanwoo Choi
2019-11-13 23:21 ` [PATCH 2/5] PM / devfreq: Split device_register usage Leonard Crestez
2019-12-02 1:08 ` Chanwoo Choi
2019-12-02 4:45 ` Leonard Crestez
2019-12-02 5:02 ` Chanwoo Choi
2019-11-13 23:21 ` [PATCH 3/5] PM / devfreq: Move more initialization before registration Leonard Crestez
2019-11-13 23:21 ` [PATCH 4/5] PM / devfreq: Don't use devm on parent device Leonard Crestez
2019-11-13 23:21 ` Leonard Crestez [this message]
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