kernel/git/stable/linux-stable.git/tools/accounting, branch linux-6.15.y

getdelays: fix error format characters

2025-02-18T06:40:02+00:00

getdelays had a compilation issue because the format string was not updated when the "delay min" was added. For example, after adding the "delay min" in printf, there were 7 strings but only 6 "%s" format specifiers. Similarly, after adding the 't->cpu_delay_total', there were 7 variables but only 6 format characters specifiers, causing compilation issues as follows. This commit fixes these issues to ensure that getdelays compiles correctly. root@xx:~/linux-next/tools/accounting$ make getdelays.c:199:9: warning: format `%llu' expects argument of type `long long unsigned int', but argument 8 has type `char *' [-Wformat=] 199 | printf("\n\nCPU %15s%15s%15s%15s%15s%15s\n" | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ..... 216 | "delay total", "delay average", "delay max", "delay min", | ~~~~~~~~~~~ | | | char * getdelays.c:200:21: note: format string is defined here 200 | " %15llu%15llu%15llu%15llu%15.3fms%13.6fms\n" | ~~~~~^ | | | long long unsigned int | %15s getdelays.c:199:9: warning: format `%f' expects argument of type `double', but argument 12 has type `long long unsigned int' [-Wformat=] 199 | printf("\n\nCPU %15s%15s%15s%15s%15s%15s\n" | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ..... 220 | (unsigned long long)t->cpu_delay_total, | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | | | long long unsigned int ..... Link: https://lkml.kernel.org/r/20250208144400544RduNRhwIpT3m2JyRBqskZ@zte.com.cn Fixes: f65c64f311ee ("delayacct: add delay min to record delay peak") Reviewed-by: xu xin Signed-off-by: Wang Yaxin Signed-off-by: Kun Jiang Cc: Balbir Singh Cc: David Hildenbrand Cc: Fan Yu Cc: Peilin He Cc: Qiang Tu Cc: wangyong Cc: ye xingchen Cc: Yunkai Zhang Signed-off-by: Andrew Morton

delayacct: add delay min to record delay peak

2025-01-13T04:21:16+00:00

Delay accounting can now calculate the average delay of processes, detect the overall system load, and also record the 'delay max' to identify potential abnormal delays. However, 'delay min' can help us identify another useful delay peak. By comparing the difference between 'delay max' and 'delay min', we can understand the optimization space for latency, providing a reference for the optimization of latency performance. Use case ========= bash-4.4# ./getdelays -d -t 242 print delayacct stats ON TGID 242 CPU count real total virtual total delay total delay average delay max delay min 39 156000000 156576579 2111069 0.054ms 0.212296ms 0.031307ms IO count delay total delay average delay max delay min 0 0 0.000ms 0.000000ms 0.000000ms SWAP count delay total delay average delay max delay min 0 0 0.000ms 0.000000ms 0.000000ms RECLAIM count delay total delay average delay max delay min 0 0 0.000ms 0.000000ms 0.000000ms THRASHING count delay total delay average delay max delay min 0 0 0.000ms 0.000000ms 0.000000ms COMPACT count delay total delay average delay max delay min 0 0 0.000ms 0.000000ms 0.000000ms WPCOPY count delay total delay average delay max delay min 156 11215873 0.072ms 0.207403ms 0.033913ms IRQ count delay total delay average delay max delay min 0 0 0.000ms 0.000000ms 0.000000ms Link: https://lkml.kernel.org/r/20241220173105906EOdsPhzjMLYNJJBqgz1ga@zte.com.cn Co-developed-by: Wang Yong Signed-off-by: Wang Yong Co-developed-by: xu xin Signed-off-by: xu xin Signed-off-by: Wang Yaxin Co-developed-by: Kun Jiang Signed-off-by: Kun Jiang Cc: Balbir Singh Cc: David Hildenbrand Cc: Fan Yu Cc: Peilin He Cc: tuqiang Cc: ye xingchen Cc: Yunkai Zhang Signed-off-by: Andrew Morton

tools/accounting/procacct: fix minor errors

2025-01-13T04:20:59+00:00

The logfile option was documented but not working. Add it and optimized the while loop. Link: https://lkml.kernel.org/r/20241203020550.3145-1-zhangjiao2@cmss.chinamobile.com Signed-off-by: zhang jiao Reviewed-by: Dr. Thomas Orgis Signed-off-by: Andrew Morton

delayacct: add delay max to record delay peak

2025-01-13T04:20:59+00:00

Introduce the use cases of delay max, which can help quickly detect potential abnormal delays in the system and record the types and specific details of delay spikes. Problem ======== Delay accounting can track the average delay of processes to show system workload. However, when a process experiences a significant delay, maybe a delay spike, which adversely affects performance, getdelays can only display the average system delay over a period of time. Yet, average delay is unhelpful for diagnosing delay peak. It is not even possible to determine which type of delay has spiked, as this information might be masked by the average delay. Solution ========= the 'delay max' can display delay peak since the system's startup, which can record potential abnormal delays over time, including the type of delay and the maximum delay. This is helpful for quickly identifying crash caused by delay. Use case ========= bash# ./getdelays -d -p 244 print delayacct stats ON PID 244 CPU count real total virtual total delay total delay average delay max 68 192000000 213676651 705643 0.010ms 0.306381ms IO count delay total delay average delay max 0 0 0.000ms 0.000000ms SWAP count delay total delay average delay max 0 0 0.000ms 0.000000ms RECLAIM count delay total delay average delay max 0 0 0.000ms 0.000000ms THRASHING count delay total delay average delay max 0 0 0.000ms 0.000000ms COMPACT count delay total delay average delay max 0 0 0.000ms 0.000000ms WPCOPY count delay total delay average delay max 235 15648284 0.067ms 0.263842ms IRQ count delay total delay average delay max 0 0 0.000ms 0.000000ms [wang.yaxin@zte.com.cn: update docs and fix some spelling errors] Link: https://lkml.kernel.org/r/20241213192700771XKZ8H30OtHSeziGqRVMs0@zte.com.cn Link: https://lkml.kernel.org/r/20241203164848805CS62CQPQWG9GLdQj2_BxS@zte.com.cn Co-developed-by: Wang Yong Signed-off-by: Wang Yong Co-developed-by: xu xin Signed-off-by: xu xin Co-developed-by: Wang Yaxin Signed-off-by: Wang Yaxin Signed-off-by: Kun Jiang Cc: Balbir Singh Cc: David Hildenbrand Cc: Fan Yu Cc: Peilin He Cc: tuqiang Cc: Yang Yang Cc: ye xingchen Cc: Yunkai Zhang Signed-off-by: Andrew Morton

delayacct: track delays from IRQ/SOFTIRQ

2023-04-18T23:39:34+00:00

Delay accounting does not track the delay of IRQ/SOFTIRQ. While IRQ/SOFTIRQ could have obvious impact on some workloads productivity, such as when workloads are running on system which is busy handling network IRQ/SOFTIRQ. Get the delay of IRQ/SOFTIRQ could help users to reduce such delay. Such as setting interrupt affinity or task affinity, using kernel thread for NAPI etc. This is inspired by "sched/psi: Add PSI_IRQ to track IRQ/SOFTIRQ pressure"[1]. Also fix some code indent problems of older code. And update tools/accounting/getdelays.c: / # ./getdelays -p 156 -di print delayacct stats ON printing IO accounting PID 156 CPU count real total virtual total delay total delay average 15 15836008 16218149 275700790 18.380ms IO count delay total delay average 0 0 0.000ms SWAP count delay total delay average 0 0 0.000ms RECLAIM count delay total delay average 0 0 0.000ms THRASHING count delay total delay average 0 0 0.000ms COMPACT count delay total delay average 0 0 0.000ms WPCOPY count delay total delay average 36 7586118 0.211ms IRQ count delay total delay average 42 929161 0.022ms [1] commit 52b1364ba0b1("sched/psi: Add PSI_IRQ to track IRQ/SOFTIRQ pressure") Link: https://lkml.kernel.org/r/202304081728353557233@zte.com.cn Signed-off-by: Yang Yang Cc: Jiang Xuexin Cc: wangyong Cc: junhua huang Cc: Balbir Singh Cc: Ingo Molnar Cc: Jonathan Corbet Cc: Juri Lelli Cc: Peter Zijlstra Signed-off-by: Andrew Morton

delayacct: improve the average delay precision of getdelay tool to microsecond

2023-04-08T20:45:36+00:00

Improve the average delay precision of getdelay tool to microsecond. When using the getdelay tool, it is sometimes found that the average delay except CPU is not 0, but display is 0, because the precison is too low. For example, see delay average of SWAP below when using ZRAM. print delayacct stats ON PID 32915 CPU count real total virtual total delay total delay average 339202 2793871936 9233585504 7951112 0.000ms IO count delay total delay average 41 419296904 10ms SWAP count delay total delay average 242589 1045792384 0ms This wrong display is misleading, so improve the millisecond precision of the average delay to microsecond just like CPU. Then user would get more accurate information of delay time. Link: https://lkml.kernel.org/r/202302131408087983857@zte.com.cn Signed-off-by: Wang Yong Reviewed-by: Yang Yang Cc: David Hildenbrand Signed-off-by: Andrew Morton

tools/accounting/procacct: remove some unused variables

2022-11-18T21:55:09+00:00

Drop the following unused variables inherited from getdelays.c: 'aggr_len', 'len2', 'cmd_type', 'tid', 'containerset', 'containerpath' and 'sigset'. Link: https://lkml.kernel.org/r/20221031091557.192180-1-wangxiongfeng2@huawei.com Signed-off-by: Xiongfeng Wang Cc: "Dr. Thomas Orgis" Cc: Ismael Luceno Cc: Xiongfeng Wang Cc: Yang Yingliang Signed-off-by: Andrew Morton

delayacct: remove some unused variables

2022-06-17T02:58:21+00:00

Drop the unused variables *done* and *count*. Link: https://lkml.kernel.org/r/20220609144459.86379-1-zhangkkoo@126.com Signed-off-by: cxbing Signed-off-by: Andrew Morton

delayacct: track delays from write-protect copy

2022-06-01T22:55:25+00:00

Delay accounting does not track the delay of write-protect copy. When tasks trigger many write-protect copys(include COW and unsharing of anonymous pages[1]), it may spend a amount of time waiting for them. To get the delay of tasks in write-protect copy, could help users to evaluate the impact of using KSM or fork() or GUP. Also update tools/accounting/getdelays.c: / # ./getdelays -dl -p 231 print delayacct stats ON listen forever PID 231 CPU count real total virtual total delay total delay average 6247 1859000000 2154070021 1674255063 0.268ms IO count delay total delay average 0 0 0ms SWAP count delay total delay average 0 0 0ms RECLAIM count delay total delay average 0 0 0ms THRASHING count delay total delay average 0 0 0ms COMPACT count delay total delay average 3 72758 0ms WPCOPY count delay total delay average 3635 271567604 0ms [1] commit 31cc5bc4af70("mm: support GUP-triggered unsharing of anonymous pages") Link: https://lkml.kernel.org/r/20220409014342.2505532-1-yang.yang29@zte.com.cn Signed-off-by: Yang Yang Reviewed-by: David Hildenbrand Reviewed-by: Jiang Xuexin Reviewed-by: Ran Xiaokai Reviewed-by: wangyong Cc: Jonathan Corbet Cc: Balbir Singh Cc: Mike Kravetz Cc: Stephen Rothwell Signed-off-by: Andrew Morton

taskstats: version 12 with thread group and exe info

2022-04-29T21:38:03+00:00

The task exit struct needs some crucial information to be able to provide an enhanced version of process and thread accounting. This change provides: 1. ac_tgid in additon to ac_pid 2. thread group execution walltime in ac_tgetime 3. flag AGROUP in ac_flag to indicate the last task in a thread group / process 4. device ID and inode of task's /proc/self/exe in ac_exe_dev and ac_exe_inode 5. tools/accounting/procacct as demonstrator When a task exits, taskstats are reported to userspace including the task's pid and ppid, but without the id of the thread group this task is part of. Without the tgid, the stats of single tasks cannot be correlated to each other as a thread group (process). The taskstats documentation suggests that on process exit a data set consisting of accumulated stats for the whole group is produced. But such an additional set of stats is only produced for actually multithreaded processes, not groups that had only one thread, and also those stats only contain data about delay accounting and not the more basic information about CPU and memory resource usage. Adding the AGROUP flag to be set when the last task of a group exited enables determination of process end also for single-threaded processes. My applicaton basically does enhanced process accounting with summed cputime, biggest maxrss, tasks per process. The data is not available with the traditional BSD process accounting (which is not designed to be extensible) and the taskstats interface allows more efficient on-the-fly grouping and summing of the stats, anyway, without intermediate disk writes. Furthermore, I do carry statistics on which exact program binary is used how often with associated resources, getting a picture on how important which parts of a collection of installed scientific software in different versions are, and how well they put load on the machine. This is enabled by providing information on /proc/self/exe for each task. I assume the two 64-bit fields for device ID and inode are more appropriate than the possibly large resolved path to keep the data volume down. Add the tgid to the stats to complete task identification, the flag AGROUP to mark the last task of a group, the group wallclock time, and inode-based identification of the associated executable file. Add tools/accounting/procacct.c as a simplified fork of getdelays.c to demonstrate process and thread accounting. [thomas.orgis@uni-hamburg.de: fix version number in comment] Link: https://lkml.kernel.org/r/20220405003601.7a5f6008@plasteblaster Link: https://lkml.kernel.org/r/20220331004106.64e5616b@plasteblaster Signed-off-by: Dr. Thomas Orgis Reviewed-by: Ismael Luceno Cc: Balbir Singh Cc: Eric W. Biederman Cc: xu xin Cc: Yang Yang Signed-off-by: Andrew Morton