linux-kernel - [PATCH] ACPI: platform_profile: Optimize _aggregate

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Message-Id: <20250322-pprof-opt-v1-1-105455879a82@gmail.com>
Date: Sat, 22 Mar 2025 18:03:37 -0300
From: Kurt Borja <kuurtb@...il.com>
To: "Rafael J. Wysocki" <rafael@...nel.org>, 
 Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>, 
 Mark Pearson <mpearson-lenovo@...ebb.ca>
Cc: Mario Limonciello <mario.limonciello@....com>, 
 Armin Wolf <W_Armin@....de>, Len Brown <lenb@...nel.org>, 
 linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Kurt Borja <kuurtb@...il.com>
Subject: [PATCH] ACPI: platform_profile: Optimize _aggregate_choices()

Choices aggregates passed to _aggregate_choices() are already filled
with ones, therefore we can avoid copying a new bitmap on the first
iteration.

This makes setting the PLATFORM_PROFILE_LAST bit on aggregates
unnecessary, so drop it as well.

While at it, add a couple empty lines to improve style.

Signed-off-by: Kurt Borja <kuurtb@...il.com>
---
 drivers/acpi/platform_profile.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
index ef9444482db1982b19d2a17884e1c3ab0e5cb55c..b5b24b075af6dfa612d56eb95342c6af87a60d3e 100644
--- a/drivers/acpi/platform_profile.c
+++ b/drivers/acpi/platform_profile.c
@@ -256,12 +256,10 @@ static int _aggregate_choices(struct device *dev, void *arg)
 	struct platform_profile_handler *handler;
 
 	lockdep_assert_held(&profile_lock);
+
 	handler = to_pprof_handler(dev);
 	bitmap_or(tmp, handler->choices, handler->hidden_choices, PLATFORM_PROFILE_LAST);
-	if (test_bit(PLATFORM_PROFILE_LAST, data->aggregate))
-		bitmap_copy(data->aggregate, tmp, PLATFORM_PROFILE_LAST);
-	else
-		bitmap_and(data->aggregate, tmp, data->aggregate, PLATFORM_PROFILE_LAST);
+	bitmap_and(data->aggregate, tmp, data->aggregate, PLATFORM_PROFILE_LAST);
 	data->count++;
 
 	return 0;
@@ -305,7 +303,6 @@ static ssize_t platform_profile_choices_show(struct device *dev,
 	};
 	int err;
 
-	set_bit(PLATFORM_PROFILE_LAST, data.aggregate);
 	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) {
 		err = class_for_each_device(&platform_profile_class, NULL,
 					    &data, _aggregate_choices);
@@ -422,7 +419,7 @@ static ssize_t platform_profile_store(struct device *dev,
 	i = sysfs_match_string(profile_names, buf);
 	if (i < 0 || i == PLATFORM_PROFILE_CUSTOM)
 		return -EINVAL;
-	set_bit(PLATFORM_PROFILE_LAST, data.aggregate);
+
 	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) {
 		ret = class_for_each_device(&platform_profile_class, NULL,
 					    &data, _aggregate_choices);
@@ -502,7 +499,6 @@ int platform_profile_cycle(void)
 	enum platform_profile_option profile = PLATFORM_PROFILE_LAST;
 	int err;
 
-	set_bit(PLATFORM_PROFILE_LAST, data.aggregate);
 	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) {
 		err = class_for_each_device(&platform_profile_class, NULL,
 					    &profile, _aggregate_profiles);

---
base-commit: 9a43102daf64dd0d172d8b39836dbc1dba4da1ea
change-id: 20250322-pprof-opt-caa7f7f349b8

Best regards,
-- 
Kurt Borja <kuurtb@...il.com>