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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /drivers/leds/trigger/ledtrig-backlight.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'drivers/leds/trigger/ledtrig-backlight.c')
-rw-r--r--drivers/leds/trigger/ledtrig-backlight.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c
new file mode 100644
index 000000000..e67bc7c2a
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-backlight.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Backlight emulation LED trigger
+ *
+ * Copyright 2008 (C) Rodolfo Giometti <giometti@linux.it>
+ * Copyright 2008 (C) Eurotech S.p.A. <info@eurotech.it>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include "../leds.h"
+
+#define BLANK 1
+#define UNBLANK 0
+
+struct bl_trig_notifier {
+ struct led_classdev *led;
+ int brightness;
+ int old_status;
+ unsigned invert;
+
+ struct list_head entry;
+};
+
+static DEFINE_MUTEX(ledtrig_backlight_list_mutex);
+static LIST_HEAD(ledtrig_backlight_list);
+
+static void ledtrig_backlight_notify_blank(struct bl_trig_notifier *n, int new_status)
+{
+ struct led_classdev *led = n->led;
+
+ if (new_status == n->old_status)
+ return;
+
+ if ((n->old_status == UNBLANK) ^ n->invert) {
+ n->brightness = led->brightness;
+ led_set_brightness_nosleep(led, LED_OFF);
+ } else {
+ led_set_brightness_nosleep(led, n->brightness);
+ }
+
+ n->old_status = new_status;
+}
+
+void ledtrig_backlight_blank(bool blank)
+{
+ struct bl_trig_notifier *n;
+ int new_status = blank ? BLANK : UNBLANK;
+
+ guard(mutex)(&ledtrig_backlight_list_mutex);
+
+ list_for_each_entry(n, &ledtrig_backlight_list, entry)
+ ledtrig_backlight_notify_blank(n, new_status);
+}
+EXPORT_SYMBOL(ledtrig_backlight_blank);
+
+static ssize_t bl_trig_invert_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct bl_trig_notifier *n = led_trigger_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", n->invert);
+}
+
+static ssize_t bl_trig_invert_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t num)
+{
+ struct led_classdev *led = led_trigger_get_led(dev);
+ struct bl_trig_notifier *n = led_trigger_get_drvdata(dev);
+ unsigned long invert;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &invert);
+ if (ret < 0)
+ return ret;
+
+ if (invert > 1)
+ return -EINVAL;
+
+ n->invert = invert;
+
+ /* After inverting, we need to update the LED. */
+ if ((n->old_status == BLANK) ^ n->invert)
+ led_set_brightness_nosleep(led, LED_OFF);
+ else
+ led_set_brightness_nosleep(led, n->brightness);
+
+ return num;
+}
+static DEVICE_ATTR(inverted, 0644, bl_trig_invert_show, bl_trig_invert_store);
+
+static struct attribute *bl_trig_attrs[] = {
+ &dev_attr_inverted.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(bl_trig);
+
+static int bl_trig_activate(struct led_classdev *led)
+{
+ struct bl_trig_notifier *n;
+
+ n = kzalloc_obj(struct bl_trig_notifier);
+ if (!n)
+ return -ENOMEM;
+ led_set_trigger_data(led, n);
+
+ n->led = led;
+ n->brightness = led->brightness;
+ n->old_status = UNBLANK;
+
+ guard(mutex)(&ledtrig_backlight_list_mutex);
+ list_add(&n->entry, &ledtrig_backlight_list);
+
+ return 0;
+}
+
+static void bl_trig_deactivate(struct led_classdev *led)
+{
+ struct bl_trig_notifier *n = led_get_trigger_data(led);
+
+ guard(mutex)(&ledtrig_backlight_list_mutex);
+ list_del(&n->entry);
+
+ kfree(n);
+}
+
+static struct led_trigger bl_led_trigger = {
+ .name = "backlight",
+ .activate = bl_trig_activate,
+ .deactivate = bl_trig_deactivate,
+ .groups = bl_trig_groups,
+};
+module_led_trigger(bl_led_trigger);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("Backlight emulation LED trigger");
+MODULE_LICENSE("GPL v2");