Uplock Roller (RG) Warning cam. This module parameter enables CPU stall detection by default, but may be overridden via boot-time parameter or at runtime via sysfs. I already get complaints about RCU CPU stall warnings producing more output than people like. McKenney 0 siblings, 1 reply; 2+ messages in thread From: Zqiang @ 2022-05-18 11:43 UTC (permalink / raw) To: paulmck, frederic; +Cc: rcu, linux-kernel This commit adds a "D" indicator to expedited RCU. I already get complaints about RCU CPU stall warnings producing more output than people like. v4 --> v5: 1. You should be able to get that reproduced under QEMU with the Versatile Express platform emulating a Cortex A15 CPU and the attached files. From the documentation about RCU stall detector: The following problems can result in RCU CPU stall warnings:. v4 --> v5: 1. Finally, this document explains the stall detector’s “splat” format. Nov 15, 2022 · From:: Robert Elliott <elliott-AT-hpe. 25 ກ. Check our new training course. Ivan Babrou Performance @ Cloudflare. Please note that PREEMPT_RCU builds can be stalled by tasks as well as by CPUs, and that the tasks will be indicated by PID, for example, “P3421”. Solution Unverified - Updated December 2 2020 at 2:59 AM - English Issue Soft lockups and RCU sched CPU stalls are detected where many CPUs are looping in a spinlock. Web. Using RCU’s CPU Stall Detector. Debugging rcu stalls. This issue was not present when we used L4. 173525] NMI watchdog: Watchdog detected hard LOCKUP on cpu 10 [ 5653. They have also tried applying: e97a32a5a3bc ("rcu: Do RCU GP kthread self-wakeup from softirq and interrupt") without reverting 016a8fc59d14, but it does not fix the problem. org> Subject: IP27: debugging RCU stalls. This message will normally be followed by stack dumps for each CPU. Aligns the output of the last line of RCU stall. This module parameter enables CPU stall detection by default, but may be overridden via boot-time parameter or at runtime via sysfs. Change "rcu stall" to "RCU stall". more detailed RCU debugging trace which points the finger at kswapd0. Either way, the: system will eventually run out of memory and hang. v5 --> v6: 1. Resolve a git am conflict. Debugging rcu stalls. Using the latest versions of kernels and inits I get the following repeating indefinitely: rcu: INFO: rcu_sched self-detected stall on CPU rcu: 0-. . Debugging rcu stalls. A small debug dump excerpt from the console characterising every stall, copied by hand (in case of any errors and for a detailed trace please consult this image): INFO: rcu_preempt detected stalls on CPUs/tasks: { 0} (detected by 1, t=2102 jiffies, g=50012, c=50011, q=6543) [<8077bd70>] (__schedule) from [<80a7ffa0>] (init_thread_union+0x1fa0. Thanks! Chris Norris. Resolve a git am conflict. Analyze the vmcore for the root cause of RCU stalls. /iwlist wlan0 scan [446. But if you're going to provide the > > > RCU-flavor integers, they should be in RCU itself and refer to RCU > > > flavors, rather than being in rcutorture and refering to test types. Sometimes we observe RCU stall warnings immediately after device boots up and sometimes we observe after running the device for longs hours (> 12 hours). We had tried many methods like remove drivers, run memtester, or make CPU busy. This will prevent RCU callbacks from ever being invoked, and in a CONFIG_PREEMPT_RCU kernel will further prevent: RCU grace periods from ever completing. On more esoteric configurations, it may be necessary to use other commands to access the output of the printk() s used by the RCU torture test. IP27: debugging RCU stalls under newer code. Paul E. Sep 12, 2017 · Decoding Those Inscrutable RCU CPU Stall Warnings, September 12, 2017 Example RCU CPU Stall Warning Splat (First Format) INFO: rcu_sched detected stalls on CPUs/tasks: 0-. IP27: debugging RCU stalls under newer code. Fine-Tuning the RCU CPU Stall Detector The rcuupdate. debug | 13 +++ kernel/rcu/rcu. RCU stall warnings and hence system hangs after seeing crashes. > > > > Fair enough, will take that approach! > > > > I am thinking in terms of something like the following: > > > > RCU_FLAVOR > > RCU_BH_FLAVOR > > RCU_SCHED. LKML Archive on lore. This parameter defines the period of time that RCU will wait from the beginning of an expedited grace period until it issues an RCU CPU stall warning. Change "rcu stall" to "RCU stall". It has NFS/SMB and MDADM installed. Anyway, your thread seems to have been held up for 59 seconds (assuming a 250 hertz kernel). v2 --> v3: 1. v5 --> v6: 1. The issue occurrence is random but exists. rcu_sched stall OR kernel panic on PowerEdge R640. Hi, We are doing thermal testing for our custom boards at -20 degree Celsius temperature. 457729] 3-. McKenney" <paulmck@kernel. v4 --> v5: 1. RCU stalls in dmesg [ 4923. Both causes are likely on Virtual Machines. Using RCU’s CPU Stall Detector. What Causes RCU CPU Stall. If your goal is to debug kernel problems, this is great because it . BTW, the 20 for CONFIG_RCU_EXP_STALL_TIMEOUT wasn't my invention, but it comes from generic Ubuntu stock kernel (but without KASAN or KMEMLEAK config options):. 413326] all qses seen, last rcu_sched kthread activity 6233 (4295220632-4295214399), jiffies_till_next_fqs=2, root ->qsmask 0x0. Change "rcu stall" to "RCU stall". For a 250 hz kernel a jiffi is 4 milliseconds, and for a 1000 hertz kernel a jiffi is 1 millisecond. 4 (known good, but no allocation stall logging) Investigate without affecting customers Bisection pointed at OS upgrade, kernel was not responsible. Booting with 38400bps, plus enabling CONFIG_RCU_FAST_NO_HZ and CONFIG_RCU_NOCB_CPU. 123, recently we ran into rcd preempt CPU stall issue and kernel hangs, while running overnight, as part of debugging , I removed the non used . Web. Fix the return type of kstat_cpu_irqs_sum () > > 2. rcu_assign_pointer () acts like an assignment statement, but does debug checking and enforces ordering on both compiler and CPU as needed. Web. This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. > > v4 --> v5: > 1. Change "rcu stall" to "RCU stall". Rename rcu_cpu_stall_deep_debug to rcu_cpu_stall_cputime. Web. panic_on_rcu_stall parameter added to sysctl to debug RCU stalls on a vmcore. When there are more than two continuous RCU stallings, correctly handle the value of the second and subsequent sampling periods. Web. v5 --> v6: 1. 000000] Kernel command line: earlycon console=ttyPS0,115200 clk_ignore_unused root=/dev/mmcblk1p2 rw rootwait [ 0. 123 with Imx6Q processor, we are getting rcu_preempt error and cpu hangs, The HW doesnt have HDMI or any on screen dispay, however the device had configurations and device tree for, GPU and HDMI enabled. Move the start point of statistics from rcu_stall_kick_kthreads() to rcu_implicit_dynticks_qs(), removing the dependency on irq_work. Resolve a git am conflict. This message indicates that CPU 32 detected that CPUs 2 and 16 were both causing stalls, and that the stall was affecting RCU-sched. 929662] rcu: INFO: rcu_preempt detected stalls on. McKenney wrote: > > > And here is a patch. The RCU callbacks are responsible for performing the necessary RCU work to achieve the end of a grace period. . The following problems can result in RCU CPU stall warnings: o A CPU looping in an RCU read-side critical section. Please note that PREEMPT_RCU builds can be stalled by tasks as well as by CPUs, and that the tasks will be indicated by PID, for example, “P3421”. 413326] all qses seen, last rcu_sched kthread activity 6233 (4295220632-4295214399), jiffies_till_next_fqs=2, root ->qsmask 0x0. Debugging rcu stalls. Aligns the output of the last line of RCU stall. 173525] NMI watchdog: Watchdog detected hard LOCKUP on cpu 10 [ 5653. System logs: Jul 28 04:24:10 kernel: INFO: rcu_sched self-detected stall on CPU Jul 28 04:24:10 kernel: INFO: rcu_sched det. org> In-Reply-To: <20210906012052. Update comments and document. For each stalled CPU that is aware of the current RCU grace period, print out additional . 900000 PCI: Using ACPI for IRQ routing 61. Web. Soft lockups and RCU sched CPU stalls are detected where many CPUs are looping in a spinlock. 900000 PCI: Using ACPI for IRQ routing 61. When there are more than two continuous RCU stallings, correctly handle the value of the second and subsequent sampling periods. The stalls are bad enough to cause hard drives to get kicked out of MD. 4844dec36bddb48 100644 > --- a/kernel/rcu/rcu. As a result, if NVDIMMs are present in the system, they are exposed through the /dev/pmem* device nodes and can be configured by using the ndctl utility. Resolve a git am conflict. org help / color / mirror / Atom feed * [PATCH] rcu: Add cpu-exp indicator to expedited RCU CPU stall warnings @ 2022-05-18 11:43 Zqiang 2022-05-18 18:14 ` Paul E. > > > > Fair enough, will take that approach! > > > > I am thinking in terms of something like the following: > > > > RCU_FLAVOR > > RCU_BH_FLAVOR > > RCU_SCHED. with Creative Commons CC-BY-SA. Add Kconfig option CONFIG_RCU_CPU_STALL_DEEP_DEBUG and boot parameter rcupdate. In the process of debugging the RCU_preempt issue , I disabled the no used peripherals + HDMI and GPU, after disabling I am not seeing the RCU_preempt issue. We have seen a recent uptick in reports of rcu_sched stalls with kernel panics Maybe we are running into this issue more often as the core counts go up on these processors. The RCU callbacks are responsible for performing the necessary RCU work to achieve the end of a grace period. 979162] NMI watchdog: BUG: soft lockup - CPU#26 stuck for 23s! [ptlrpcd_00_00:12056] [56376. Add comments and normalize local variable name v1 --> v2: 1. └─> Print additional diagnostics on RCU CPU stall. v5 --> v6: 1. INFO: rcu detected stall in corrupted rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { P4085 } 2680 jiffies s: 2529 root: 0x0/T rcu: blocking rcu_node structures (internal RCU debug): Tested on: commit: 55be6084 Merge tag 'timers-core-2022-10-05' of git://g. 3. A modified kernel module with printk() enabled calls has been loaded for debugging purposes. Web. 000000] software IO TLB: mapped [mem 0x7bfff000. Web. Update comments and document. 000000] Kernel command line: earlycon console=ttyPS0,115200 clk_ignore_unused root=/dev/mmcblk1p2 rw rootwait [ 0. 0: (1 GPs behind) idle=bf2/140000000000000/0 softirq=554/555 fqs=6754 (detected by 1, t=21003 jiffies, g=-154, c=-155, q=120339) Sending NMI from CPU 1 to CPUs 0:. In computer science, read-copy-update (RCU) is a synchronization mechanism that avoids the use of lock primitives while multiple threads concurrently read . Finally, this document explains the stall detector’s “splat” format. > > > > Fair enough, will take that approach! > > > > I am thinking in terms of something like the following: > > > > RCU_FLAVOR > > RCU_BH_FLAVOR > > RCU_SCHED. Change "rcu stall" to "RCU stall". Add comments and normalize local variable name > > > > v1 --> v2: > > 1. Update comments and document. The panic_on_rcu_stall interface is useful for defining the root cause of RCU stalls when using a vmcore. This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. When CPU idle<10%, RCU stall warnings occurs after >24hour. > 2. Update comments and > document. v4 --> v5: 1. Finally, this document explains the stall detector’s “splat” format. Anyway, your thread seems to have been held up for 59 seconds (assuming a 250 hertz kernel). Thanks!-- Florian #include <stdlib. 16 ມ. When there are more than two continuous RCU stallings, correctly handle the value of the second and subsequent sampling periods. Thanks to Elliott, Robert for the test. 5 ກ. RCU stall warnings and hence system hangs after seeing crashes. random rcu stalls and soft cpu lockups when running jobs on the cluster. soft lockups:. The stalls are bad enough to cause hard drives to get kicked out of MD. This condition can result in RCU-sched stalls and, if ksoftirqd is in use, RCU-bh stalls. In the vast majority of cases, real-time users face RCU stalls due to the delay of RCU callbacks execution. Resolve a git am conflict. If the rcu stall is detected by another CPU, >> kcpustat_this_cpu cannot be used. . Update comments and document. Using RCU’s CPU Stall Detector. ub with mkimage from. Most recently Seen. 733084] rcu: blocking rcu_node structures (internal RCU debug): [ 29. McKenney 0 siblings, 1 reply; 2+ messages in thread From: Zqiang @ 2022-05-18 11:43 UTC (permalink / raw) To: paulmck, frederic; +Cc: rcu, linux-kernel This commit adds a "D" indicator to expedited RCU. The kernel actually doesn't get to run on a CPU time within a certain timespan, either caused by timer not executed or different expectation of a timer speed. Fixed a bug in the code. Web. The panic_on_rcu_stall interface is useful for defining the root cause of RCU . Web. Gwangbokdong Food Street was a great local experience. Please note that PREEMPT_RCU builds can be stalled by tasks as well as by CPUs, and that the tasks will be indicated by PID, for example, “P3421”. We have seen a recent uptick in reports of rcu_sched stalls with kernel panics Maybe we are running into this issue more often as the core counts go up on these processors. 5 ກ. You get this warning if you stop the program execution longer than the RCU timeout (CONFIG_RCU_CPU_STALL_TIMEOUT). 62 Beta BSP. Accelleration: VT-x/AMD-V, Nested Paging, KVM Paravirtualization. > (2) Do you mean to suppress such new debugging information that I added? > or the whole RCU stall information? Only the new debugging information. This module parameter enables CPU stall detection by default, but may be overridden via boot-time parameter or at runtime via sysfs. Update comments and document. Web. Thanks to Elliott, Robert for the test. v4 --> v5: 1. Kernel hard LOCKUP and rcu_sched stalls caused by a slow responding serial console interface. Thanks to Elliott, Robert for the test. arm, arm64: rcu_preempt self-detected stall. Using RCU’s CPU Stall Detector. rcu_cpu_stall_suppress module parameter disables RCU’s CPU stall detector, which detects conditions that unduly delay RCU grace periods. In the vast majority of cases, real-time users face RCU stalls due to the delay of RCU callbacks execution. In the vast majority of cases, real-time users face RCU stalls due to the delay of RCU callbacks execution. Add Kconfig option CONFIG_RCU_CPU_STALL_DEEP_DEBUG and boot parameter rcupdate. 18 ພ. This feature can detect looping CPUs in !PREEMPT builds and looping CPUs with preemption disabled in PREEMPT builds. A small debug dump excerpt from the console characterising every stall, copied by hand (in case of any errors and for a detailed trace please consult this image): INFO: rcu_preempt detected stalls on CPUs/tasks: { 0} (detected by 1, t=2102 jiffies, g=50012, c=50011, q=6543) [<8077bd70>] (__schedule) from [<80a7ffa0>] (init_thread_union+0x1fa0. BTW, the 20 for CONFIG_RCU_EXP_STALL_TIMEOUT wasn't my invention, but it comes from generic Ubuntu stock kernel (but without KASAN or KMEMLEAK config options):. Web. org help / color / mirror / Atom feed * [PATCH] rcu: Add cpu-exp indicator to expedited RCU CPU stall warnings @ 2022-05-18 11:43 Zqiang 2022-05-18 18:14 ` Paul E. v5 --> v6: 1. Resolve a git am conflict. This module parameter enables CPU stall detection by default, but may be overridden via boot-time parameter or at runtime via sysfs. Web. Nov 11, 2022 · 3. This issue was not present when we used L4. v3 --> v4: 1. com> To:: herbert-AT-gondor. If I hit F5 and then the 'Get Feed' button, the UI becomes. The following log will be printed repeatedly。 How to debug this issue?This problem is inevitable. h> #include <string. No code change. Kernel hard LOCKUP and rcu_sched stalls caused by a slow responding serial console interface This document (000020516) is provided subject to the disclaimer at the end of this document. When there are more than two continuous RCU stallings, correctly handle the value of the second and subsequent sampling periods. , the issue occurrence is still random but exists. 462841] INFO: rcu_sched self-detected stall on CPU [ 4923. set rcu_cpu_stall_suppress = 1 Helpful Unhelpful. AMD has been working on adding support for GPU compute debugging to GDB. In this case, the printed information about current is not useful. says to use the RCU_CPU_STALL_TIMEOUT value converted from seconds to milliseconds. rcu_cpu_stall_suppress module parameter disables RCU’s CPU stall detector, which detects conditions that unduly delay RCU grace periods. The RCU callbacks are responsible for performing the necessary RCU work to achieve the end of a grace period. A third fix, which works only if this code does > >not use RCU and does not invoke any code that does use RCU, is to tell > >RCU that it should ignore this code (which will require a little work > >on RCU, as it currently does not tolerate this sort of thing aside from > >the idle threads). Change "rcu stall" to "RCU stall". Would you please help us in how we can resolve the issue. Feb 10, 2020 · The issue occurrence is random but exists. v5 --> v6: 1. *kthread starved for”关键字，以及一些额外的debug信息（详细信息后面会有示例）。 （8）在开了CONFIG_PREEMPT的内核中，一个绑核的rt线程可能 . Web. creampie v, belssa porn
: (52300 ticks this GP) idle=439/140000000000001/0 softirq=806264/806264 fqs=52291 INFO:. . Debugging rcu stalls
The stall detector's idea of what constitutes "unduly delayed" is. The issue occurrence is random but exists. org help / color / mirror / Atom feed * [PATCH] rcu: Add cpu-exp indicator to expedited RCU CPU stall warnings @ 2022-05-18 11:43 Zqiang 2022-05-18 18:14 ` Paul E. Finally, this document explains the stall detector’s “splat” format. > > > > Fair enough, will take that approach! > > > > I am thinking in terms of something like the following: > > > > RCU_FLAVOR > > RCU_BH_FLAVOR > > RCU_SCHED. Finally, this document explains the stall detector’s “splat” format. org> In-Reply-To: <20210906012052. IP27: debugging RCU stalls under newer code. rcu: INFO: rcu_preempt self-detected stall on CPU. Add Kconfig option CONFIG_RCU_CPU_STALL_DEEP_DEBUG and boot parameter rcupdate. v4 --> v5: 1. LKML Archive on lore. This message will normally be followed by stack dumps for each CPU. In the: CONFIG_PREEMPT_RCU case, you might see stall-warning. Update comments and document. Using RCU’s CPU Stall Detector. Re: rcu self-detected stall messages on OMAP3. This feature can detect looping CPUs in !PREEMPT builds and looping CPUs with preemption disabled in PREEMPT builds. On my Wildcat_Pass (Haswell) board, the system boot will hang as below. This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. Although a RCU Stall can be a side effect of a kernel BUG, this is not the typical case for the real-time kernel users. This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. It indicates, "Click to perform a search". This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. Web. Although a RCU Stall can be a side effect of a kernel BUG, this is not the typical case for the real-time kernel users. Resolve a git am conflict. from [Joshua Kinard] [Permanent Link] To: Linux/MIPS <linux-mips@linux-mips. Web. Finally, this document explains the stall detector’s “splat” format. Sometimes we observe RCU stall warnings immediately after device boots up and sometimes we observe after running the device for longs hours (> 12 hours). v2 --> v3: 1. 16 ມ. Change "rcu stall" to "RCU stall". RCU stall warnings and hence system hangs after seeing crashes. INFO: rcu_preempt detected stalls on CPUs/tasks: 2021-11-15T09:47:25Z xi-1B-D8-3E user. its file specification with only devicetree and kernel beein in the image. Web. Web. ;-) It -might- be possible to do this automatically, but reliable. It is fully updated. org help / color / mirror / Atom feed * [PATCH] rcu: Add cpu-exp indicator to expedited RCU CPU stall warnings @ 2022-05-18 11:43 Zqiang 2022-05-18 18:14 ` Paul E. h > +++ b/kernel/rcu/rcu. Using RCU’s CPU Stall Detector. Web. TDA4VM: rcu: INFO: rcu_preempt detected stalls on CPUs fengying li Prodigy 170 points Part Number: TDA4VM hi TI When system run long time the system will abnormal, our SDK version is 08. In the vast majority of cases, real-time users face RCU stalls due to the delay of RCU callbacks execution. And as we all know, evolutionary forces are driven by random changes, which absolutely anyone could make. IP27 prints early PROM messages at 9600bps at poweron, thus not changing the baud rate very often. Update comments and document. The panic_on_rcu_stall interface is useful for defining the root cause of RCU stalls when using a vmcore. In the vast majority of cases, real-time users face RCU stalls due to the delay of RCU callbacks execution. rcu_cpu_stall_suppress module parameter disables RCU’s CPU stall detector, which detects conditions that unduly delay RCU grace periods. 它们来自RCU CPU Stall Detector，要了解RCU CPU Stall Detector是. 9 to 4. 0: (1 GPs behind) idle=bf2/140000000000000/0 softirq=554/555 fqs=6754 (detected by 1, t=21003 jiffies, g=-154, c=-155, q=120339) Sending NMI from CPU 1 to CPUs 0:. McKenney 0 siblings, 1 reply; 2+ messages in thread From: Zqiang @ 2022-05-18 11:43 UTC (permalink / raw) To: paulmck, frederic; +Cc: rcu, linux-kernel This commit adds a "D" indicator to expedited RCU. Web. v5 --> v6: 1. Although a RCU Stall can be a side effect of a kernel BUG, this is not the typical case for the real-time kernel users. v5 --> v6: 1. Fixed a bug in the code. Web. v2 --> v3: 1. Finally, this document explains the stall detector’s “splat” format. Web. 14 ສ. 144258] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:. Nov 11, 2022 · 2. When there are more than two continuous RCU stallings, correctly handle the value of the second and subsequent sampling periods. Debugging rcu stalls. Rope trick. Aligns the output of the last line of RCU stall. The command "dmesg | grep torture:" will extract this information on most systems. v3 --> v4: 1. The RCU callbacks are responsible for performing the necessary RCU work to achieve the end of a grace period. Resolve a git am conflict. 22 ມິ. The RCU callbacks are responsible for performing the necessary RCU work to achieve the end of a grace period. Change "rcu stall" to "RCU stall". debugging rcu stalls The ultimate action-packed science and technology magazine bursting with exciting information about the universe Subscribe today for our Black Frida offer - Save up to 50% Engaging articles, amazing illustrations & exclusive interviews Issues delivered straight to your door or device. Web. Although a RCU Stall can be a side effect of a kernel BUG, this is not the typical case for the real-time kernel users. 022193] rcu: INFO: rcu_sched detected stalls on CPUs/tasks:. Thanks to Elliott, Robert for the test. In the vast majority of . from [Joshua Kinard] [Permanent Link] To: Linux/MIPS <linux-mips@linux-mips. Add comments and normalize local variable name > > > > v1 --> v2: > > 1. Web. Most recently Seen. Jun 06, 2022 · Hi, I am getting occasionally kernels hanging (sometimes hours after boot) with the following output occurring and that just goes on until i reboot the machine: INFO: rcu_sched self-detected stall on CPU 1-. net, tim. This module parameter enables CPU stall detection by default, but may be overridden via boot-time parameter or at runtime via sysfs. This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. Nov 11, 2022 · 2. Web. Fine-Tuning the RCU CPU Stall Detector The rcuupdate. Web. Aligns the output of the last line of RCU stall. This message indicates that CPU 32 detected that CPUs 2 and 16 were both causing stalls, and that the stall was affecting RCU-sched. We had tried many methods like remove drivers, run memtester, or make CPU busy. Web. : (20999 ticks this GP) idle=042/1/0x4000000000000002 softirq=8/8 fqs=5248 rcu: (t=21000 jiffies g=-1179 q=18) I tried rolling back just inits to. They have also tried applying: e97a32a5a3bc ("rcu: Do RCU GP kthread self-wakeup from softirq and interrupt") Any suggestions/help are appreciated. rcu_cpu_stall_suppress module parameter disables RCU’s CPU stall detector, which detects conditions that unduly delay RCU grace periods. Finally, this document explains the stall detector’s “splat” format. Change "rcu stall" to "RCU stall". If the rcu stall is detected by another CPU, > kcpustat_this_cpu cannot be used. For a 250 hz kernel a jiffi is 4 milliseconds, and for a 1000 hertz kernel a jiffi is 1 millisecond. Thanks to Elliott, Robert for the test. Finally, this document explains the stall detector’s “splat” format. This document first discusses what sorts of issues RCU’s CPU stall detector can locate, and then discusses kernel parameters and Kconfig options that can be used to fine-tune the detector’s operation. . reality pornography