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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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+.. |tool| replace:: timerlat top
+
+====================
+rtla-timerlat-top
+====================
+-------------------------------------------
+Measures the operating system timer latency
+-------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla timerlat top** [*OPTIONS*] ...
+
+DESCRIPTION
+===========
+
+.. include:: common_timerlat_description.txt
+
+The **rtla timerlat top** displays a summary of the periodic output
+from the *timerlat* tracer. It also provides information for each
+operating system noise via the **osnoise:** tracepoints that can be
+seen with the option **-T**.
+
+OPTIONS
+=======
+
+.. include:: common_timerlat_options.txt
+
+.. include:: common_top_options.txt
+
+.. include:: common_options.txt
+
+.. include:: common_timerlat_aa.txt
+
+**--aa-only** *us*
+
+ Set stop tracing conditions and run without collecting and displaying statistics.
+ Print the auto-analysis if the system hits the stop tracing condition. This option
+ is useful to reduce rtla timerlat CPU, enabling the debug without the overhead of
+ collecting the statistics.
+
+EXAMPLE
+=======
+
+In the example below, the timerlat tracer is dispatched in cpus *1-23* in the
+automatic trace mode, instructing the tracer to stop if a *40 us* latency or
+higher is found::
+
+ # timerlat -a 40 -c 1-23 -q
+ Timer Latency
+ 0 00:00:12 | IRQ Timer Latency (us) | Thread Timer Latency (us)
+ CPU COUNT | cur min avg max | cur min avg max
+ 1 #12322 | 0 0 1 15 | 10 3 9 31
+ 2 #12322 | 3 0 1 12 | 10 3 9 23
+ 3 #12322 | 1 0 1 21 | 8 2 8 34
+ 4 #12322 | 1 0 1 17 | 10 2 11 33
+ 5 #12322 | 0 0 1 12 | 8 3 8 25
+ 6 #12322 | 1 0 1 14 | 16 3 11 35
+ 7 #12322 | 0 0 1 14 | 9 2 8 29
+ 8 #12322 | 1 0 1 22 | 9 3 9 34
+ 9 #12322 | 0 0 1 14 | 8 2 8 24
+ 10 #12322 | 1 0 0 12 | 9 3 8 24
+ 11 #12322 | 0 0 0 15 | 6 2 7 29
+ 12 #12321 | 1 0 0 13 | 5 3 8 23
+ 13 #12319 | 0 0 1 14 | 9 3 9 26
+ 14 #12321 | 1 0 0 13 | 6 2 8 24
+ 15 #12321 | 1 0 1 15 | 12 3 11 27
+ 16 #12318 | 0 0 1 13 | 7 3 10 24
+ 17 #12319 | 0 0 1 13 | 11 3 9 25
+ 18 #12318 | 0 0 0 12 | 8 2 8 20
+ 19 #12319 | 0 0 1 18 | 10 2 9 28
+ 20 #12317 | 0 0 0 20 | 9 3 8 34
+ 21 #12318 | 0 0 0 13 | 8 3 8 28
+ 22 #12319 | 0 0 1 11 | 8 3 10 22
+ 23 #12320 | 28 0 1 28 | 41 3 11 41
+ rtla timerlat hit stop tracing
+ ## CPU 23 hit stop tracing, analyzing it ##
+ IRQ handler delay: 27.49 us (65.52 %)
+ IRQ latency: 28.13 us
+ Timerlat IRQ duration: 9.59 us (22.85 %)
+ Blocking thread: 3.79 us (9.03 %)
+ objtool:49256 3.79 us
+ Blocking thread stacktrace
+ -> timerlat_irq
+ -> __hrtimer_run_queues
+ -> hrtimer_interrupt
+ -> __sysvec_apic_timer_interrupt
+ -> sysvec_apic_timer_interrupt
+ -> asm_sysvec_apic_timer_interrupt
+ -> _raw_spin_unlock_irqrestore
+ -> cgroup_rstat_flush_locked
+ -> cgroup_rstat_flush_irqsafe
+ -> mem_cgroup_flush_stats
+ -> mem_cgroup_wb_stats
+ -> balance_dirty_pages
+ -> balance_dirty_pages_ratelimited_flags
+ -> btrfs_buffered_write
+ -> btrfs_do_write_iter
+ -> vfs_write
+ -> __x64_sys_pwrite64
+ -> do_syscall_64
+ -> entry_SYSCALL_64_after_hwframe
+ ------------------------------------------------------------------------
+ Thread latency: 41.96 us (100%)
+
+ The system has exit from idle latency!
+ Max timerlat IRQ latency from idle: 17.48 us in cpu 4
+ Saving trace to timerlat_trace.txt
+
+In this case, the major factor was the delay suffered by the *IRQ handler*
+that handles **timerlat** wakeup: *65.52%*. This can be caused by the
+current thread masking interrupts, which can be seen in the blocking
+thread stacktrace: the current thread (*objtool:49256*) disabled interrupts
+via *raw spin lock* operations inside mem cgroup, while doing write
+syscall in a btrfs file system.
+
+The raw trace is saved in the **timerlat_trace.txt** file for further analysis.
+
+Note that **rtla timerlat** was dispatched without changing *timerlat* tracer
+threads' priority. That is generally not needed because these threads have
+priority *FIFO:95* by default, which is a common priority used by real-time
+kernel developers to analyze scheduling delays.
+
+SEE ALSO
+--------
+**rtla-timerlat**\(1), **rtla-timerlat-hist**\(1)
+
+`Timerlat tracer <https://docs.kernel.org/trace/timerlat-tracer.html>`__
+
+AUTHOR
+------
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.txt