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authorBreno Leitao <leitao@debian.org>2026-08-05 07:52:36 -0700
committerTejun Heo <tj@kernel.org>2026-08-10 11:47:20 -1000
commita5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch)
tree39f5b258386e1127d253d293194e9a2991bf3c34 /Documentation/ABI/testing/rtc-cdev
downloadlinux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz
linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.zip
workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
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+What: /dev/rtcX
+Date: April 2005
+KernelVersion: 2.6.12
+Contact: linux-rtc@vger.kernel.org
+Description:
+ The ioctl interface to drivers for real-time clocks (RTCs).
+ Following actions are supported:
+
+ * RTC_RD_TIME, RTC_SET_TIME: Read or set the RTC time. Time
+ format is a Gregorian calendar date and 24 hour wall clock
+ time.
+
+ * RTC_AIE_ON, RTC_AIE_OFF: Enable or disable the alarm interrupt
+ for RTCs that support alarms
+
+ * RTC_ALM_READ, RTC_ALM_SET: Read or set the alarm time for
+ RTCs that support alarms. Can be set up to 24 hours in the
+ future. Requires a separate RTC_AIE_ON call to enable the
+ alarm interrupt. (Prefer to use RTC_WKALM_*)
+
+ * RTC_WKALM_RD, RTC_WKALM_SET: For RTCs that support a more
+ powerful interface, which can issue alarms beyond 24 hours and
+ enable IRQs in the same request.
+
+ * RTC_PIE_ON, RTC_PIE_OFF: Enable or disable the periodic
+ interrupt for RTCs that support periodic interrupts.
+
+ * RTC_UIE_ON, RTC_UIE_OFF: Enable or disable the update
+ interrupt for RTCs that support it.
+
+ * RTC_IRQP_READ, RTC_IRQP_SET: Read or set the frequency for
+ periodic interrupts for RTCs that support periodic interrupts.
+ Requires a separate RTC_PIE_ON call to enable the periodic
+ interrupts.
+
+ * RTC_VL_READ: Read the voltage inputs status of the RTC when
+ supported. The value is a bit field of RTC_VL_*, giving the
+ status of the main and backup voltages.
+
+ * RTC_VL_CLEAR: Clear the voltage status of the RTC. Some RTCs
+ need user interaction when the backup power provider is
+ replaced or charged to be able to clear the status.
+
+ The ioctl() calls supported by the older /dev/rtc interface are
+ also supported by the newer RTC class framework. However,
+ because the chips and systems are not standardized, some PC/AT
+ functionality might not be provided. And in the same way, some
+ newer features -- including those enabled by ACPI -- are exposed
+ by the RTC class framework, but can't be supported by the older
+ driver.