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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
/* SPDX-License-Identifier: GPL-2.0 */
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
#undef TRACE_SYSTEM
#define TRACE_SYSTEM cgroup
#if !defined(_TRACE_CGROUP_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_CGROUP_H
#include <linux/cgroup.h>
#include <linux/tracepoint.h>
DECLARE_EVENT_CLASS(cgroup_root,
TP_PROTO(struct cgroup_root *root),
TP_ARGS(root),
TP_STRUCT__entry(
__field( int, root )
__field( u16, ss_mask )
__string( name, root->name )
),
TP_fast_assign(
__entry->root = root->hierarchy_id;
__entry->ss_mask = root->subsys_mask;
tracing/treewide: Remove second parameter of __assign_str() With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts. Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> # xfs Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-17 01:34:54 +08:00
__assign_str(name);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
),
TP_printk("root=%d ss_mask=%#x name=%s",
__entry->root, __entry->ss_mask, __get_str(name))
);
DEFINE_EVENT(cgroup_root, cgroup_setup_root,
TP_PROTO(struct cgroup_root *root),
TP_ARGS(root)
);
DEFINE_EVENT(cgroup_root, cgroup_destroy_root,
TP_PROTO(struct cgroup_root *root),
TP_ARGS(root)
);
DEFINE_EVENT(cgroup_root, cgroup_remount,
TP_PROTO(struct cgroup_root *root),
TP_ARGS(root)
);
DECLARE_EVENT_CLASS(cgroup,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *cgrp, const char *path),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(cgrp, path),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
TP_STRUCT__entry(
__field( int, root )
__field( int, level )
cgroup: Trace event cgroup id fields should be u64 Various trace event fields that store cgroup IDs were declared as ints, but cgroup_id(() returns a u64 and the structures and associated TP_printk() calls were not updated to reflect this. Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID") Signed-off-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-12-02 00:56:58 +08:00
__field( u64, id )
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
__string( path, path )
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
),
TP_fast_assign(
__entry->root = cgrp->root->hierarchy_id;
cgroup: use cgrp->kn->id as the cgroup ID cgroup ID is currently allocated using a dedicated per-hierarchy idr and used internally and exposed through tracepoints and bpf. This is confusing because there are tracepoints and other interfaces which use the cgroupfs ino as IDs. The preceding changes made kn->id exposed as ino as 64bit ino on supported archs or ino+gen (low 32bits as ino, high gen). There's no reason for cgroup to use different IDs. The kernfs IDs are unique and userland can easily discover them and map them back to paths using standard file operations. This patch replaces cgroup IDs with kernfs IDs. * cgroup_id() is added and all cgroup ID users are converted to use it. * kernfs_node creation is moved to earlier during cgroup init so that cgroup_id() is available during init. * While at it, s/cgroup/cgrp/ in psi helpers for consistency. * Fallback ID value is changed to 1 to be consistent with root cgroup ID. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-05 07:54:30 +08:00
__entry->id = cgroup_id(cgrp);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__entry->level = cgrp->level;
tracing/treewide: Remove second parameter of __assign_str() With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts. Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> # xfs Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-17 01:34:54 +08:00
__assign_str(path);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
),
cgroup: Trace event cgroup id fields should be u64 Various trace event fields that store cgroup IDs were declared as ints, but cgroup_id(() returns a u64 and the structures and associated TP_printk() calls were not updated to reflect this. Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID") Signed-off-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-12-02 00:56:58 +08:00
TP_printk("root=%d id=%llu level=%d path=%s",
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__entry->root, __entry->id, __entry->level, __get_str(path))
);
DEFINE_EVENT(cgroup, cgroup_mkdir,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *cgrp, const char *path),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(cgrp, path)
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
);
DEFINE_EVENT(cgroup, cgroup_rmdir,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *cgrp, const char *path),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(cgrp, path)
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
);
DEFINE_EVENT(cgroup, cgroup_release,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *cgrp, const char *path),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(cgrp, path)
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
);
DEFINE_EVENT(cgroup, cgroup_rename,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *cgrp, const char *path),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(cgrp, path)
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
);
cgroup: add tracing points for cgroup v2 freezer Add cgroup:cgroup_freeze and cgroup:cgroup_unfreeze events, which are using the existing cgroup tracing infrastructure. Add the cgroup_event event class, which is similar to the cgroup class, but contains an additional integer field to store a new value (the level field is dropped). Also add two tracing events: cgroup_notify_populated and cgroup_notify_frozen, which are raised in a generic way using the TRACE_CGROUP_PATH() macro. This allows to trace cgroup state transitions and is generally helpful for debugging the cgroup freezer code. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-04-20 01:03:08 +08:00
DEFINE_EVENT(cgroup, cgroup_freeze,
TP_PROTO(struct cgroup *cgrp, const char *path),
TP_ARGS(cgrp, path)
);
DEFINE_EVENT(cgroup, cgroup_unfreeze,
TP_PROTO(struct cgroup *cgrp, const char *path),
TP_ARGS(cgrp, path)
);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
DECLARE_EVENT_CLASS(cgroup_migrate,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *dst_cgrp, const char *path,
struct task_struct *task, bool threadgroup),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(dst_cgrp, path, task, threadgroup),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
TP_STRUCT__entry(
__field( int, dst_root )
__field( int, dst_level )
cgroup: Trace event cgroup id fields should be u64 Various trace event fields that store cgroup IDs were declared as ints, but cgroup_id(() returns a u64 and the structures and associated TP_printk() calls were not updated to reflect this. Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID") Signed-off-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-12-02 00:56:58 +08:00
__field( u64, dst_id )
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__field( int, pid )
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
__string( dst_path, path )
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__string( comm, task->comm )
),
TP_fast_assign(
__entry->dst_root = dst_cgrp->root->hierarchy_id;
cgroup: use cgrp->kn->id as the cgroup ID cgroup ID is currently allocated using a dedicated per-hierarchy idr and used internally and exposed through tracepoints and bpf. This is confusing because there are tracepoints and other interfaces which use the cgroupfs ino as IDs. The preceding changes made kn->id exposed as ino as 64bit ino on supported archs or ino+gen (low 32bits as ino, high gen). There's no reason for cgroup to use different IDs. The kernfs IDs are unique and userland can easily discover them and map them back to paths using standard file operations. This patch replaces cgroup IDs with kernfs IDs. * cgroup_id() is added and all cgroup ID users are converted to use it. * kernfs_node creation is moved to earlier during cgroup init so that cgroup_id() is available during init. * While at it, s/cgroup/cgrp/ in psi helpers for consistency. * Fallback ID value is changed to 1 to be consistent with root cgroup ID. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-05 07:54:30 +08:00
__entry->dst_id = cgroup_id(dst_cgrp);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__entry->dst_level = dst_cgrp->level;
tracing/treewide: Remove second parameter of __assign_str() With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts. Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> # xfs Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-17 01:34:54 +08:00
__assign_str(dst_path);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__entry->pid = task->pid;
tracing/treewide: Remove second parameter of __assign_str() With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts. Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> # xfs Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-17 01:34:54 +08:00
__assign_str(comm);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
),
cgroup: Trace event cgroup id fields should be u64 Various trace event fields that store cgroup IDs were declared as ints, but cgroup_id(() returns a u64 and the structures and associated TP_printk() calls were not updated to reflect this. Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID") Signed-off-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-12-02 00:56:58 +08:00
TP_printk("dst_root=%d dst_id=%llu dst_level=%d dst_path=%s pid=%d comm=%s",
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
__entry->dst_root, __entry->dst_id, __entry->dst_level,
__get_str(dst_path), __entry->pid, __get_str(comm))
);
DEFINE_EVENT(cgroup_migrate, cgroup_attach_task,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *dst_cgrp, const char *path,
struct task_struct *task, bool threadgroup),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(dst_cgrp, path, task, threadgroup)
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
);
DEFINE_EVENT(cgroup_migrate, cgroup_transfer_tasks,
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_PROTO(struct cgroup *dst_cgrp, const char *path,
struct task_struct *task, bool threadgroup),
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
cgroup/tracing: Move taking of spin lock out of trace event handlers It is unwise to take spin locks from the handlers of trace events. Mainly, because they can introduce lockups, because it introduces locks in places that are normally not tested. Worse yet, because trace events are tucked away in the include/trace/events/ directory, locks that are taken there are forgotten about. As a general rule, I tell people never to take any locks in a trace event handler. Several cgroup trace event handlers call cgroup_path() which eventually takes the kernfs_rename_lock spinlock. This injects the spinlock in the code without people realizing it. It also can cause issues for the PREEMPT_RT patch, as the spinlock becomes a mutex, and the trace event handlers are called with preemption disabled. By moving the calculation of the cgroup_path() out of the trace event handlers and into a macro (surrounded by a trace_cgroup_##type##_enabled()), then we could place the cgroup_path into a string, and pass that to the trace event. Not only does this remove the taking of the spinlock out of the trace event handler, but it also means that the cgroup_path() only needs to be called once (it is currently called twice, once to get the length to reserver the buffer for, and once again to get the path itself. Now it only needs to be done once. Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2018-07-10 05:48:54 +08:00
TP_ARGS(dst_cgrp, path, task, threadgroup)
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
);
cgroup: add tracing points for cgroup v2 freezer Add cgroup:cgroup_freeze and cgroup:cgroup_unfreeze events, which are using the existing cgroup tracing infrastructure. Add the cgroup_event event class, which is similar to the cgroup class, but contains an additional integer field to store a new value (the level field is dropped). Also add two tracing events: cgroup_notify_populated and cgroup_notify_frozen, which are raised in a generic way using the TRACE_CGROUP_PATH() macro. This allows to trace cgroup state transitions and is generally helpful for debugging the cgroup freezer code. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-04-20 01:03:08 +08:00
DECLARE_EVENT_CLASS(cgroup_event,
TP_PROTO(struct cgroup *cgrp, const char *path, int val),
TP_ARGS(cgrp, path, val),
TP_STRUCT__entry(
__field( int, root )
__field( int, level )
cgroup: Trace event cgroup id fields should be u64 Various trace event fields that store cgroup IDs were declared as ints, but cgroup_id(() returns a u64 and the structures and associated TP_printk() calls were not updated to reflect this. Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID") Signed-off-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-12-02 00:56:58 +08:00
__field( u64, id )
cgroup: add tracing points for cgroup v2 freezer Add cgroup:cgroup_freeze and cgroup:cgroup_unfreeze events, which are using the existing cgroup tracing infrastructure. Add the cgroup_event event class, which is similar to the cgroup class, but contains an additional integer field to store a new value (the level field is dropped). Also add two tracing events: cgroup_notify_populated and cgroup_notify_frozen, which are raised in a generic way using the TRACE_CGROUP_PATH() macro. This allows to trace cgroup state transitions and is generally helpful for debugging the cgroup freezer code. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-04-20 01:03:08 +08:00
__string( path, path )
__field( int, val )
),
TP_fast_assign(
__entry->root = cgrp->root->hierarchy_id;
cgroup: use cgrp->kn->id as the cgroup ID cgroup ID is currently allocated using a dedicated per-hierarchy idr and used internally and exposed through tracepoints and bpf. This is confusing because there are tracepoints and other interfaces which use the cgroupfs ino as IDs. The preceding changes made kn->id exposed as ino as 64bit ino on supported archs or ino+gen (low 32bits as ino, high gen). There's no reason for cgroup to use different IDs. The kernfs IDs are unique and userland can easily discover them and map them back to paths using standard file operations. This patch replaces cgroup IDs with kernfs IDs. * cgroup_id() is added and all cgroup ID users are converted to use it. * kernfs_node creation is moved to earlier during cgroup init so that cgroup_id() is available during init. * While at it, s/cgroup/cgrp/ in psi helpers for consistency. * Fallback ID value is changed to 1 to be consistent with root cgroup ID. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-05 07:54:30 +08:00
__entry->id = cgroup_id(cgrp);
cgroup: add tracing points for cgroup v2 freezer Add cgroup:cgroup_freeze and cgroup:cgroup_unfreeze events, which are using the existing cgroup tracing infrastructure. Add the cgroup_event event class, which is similar to the cgroup class, but contains an additional integer field to store a new value (the level field is dropped). Also add two tracing events: cgroup_notify_populated and cgroup_notify_frozen, which are raised in a generic way using the TRACE_CGROUP_PATH() macro. This allows to trace cgroup state transitions and is generally helpful for debugging the cgroup freezer code. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-04-20 01:03:08 +08:00
__entry->level = cgrp->level;
tracing/treewide: Remove second parameter of __assign_str() With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts. Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> # xfs Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-17 01:34:54 +08:00
__assign_str(path);
cgroup: add tracing points for cgroup v2 freezer Add cgroup:cgroup_freeze and cgroup:cgroup_unfreeze events, which are using the existing cgroup tracing infrastructure. Add the cgroup_event event class, which is similar to the cgroup class, but contains an additional integer field to store a new value (the level field is dropped). Also add two tracing events: cgroup_notify_populated and cgroup_notify_frozen, which are raised in a generic way using the TRACE_CGROUP_PATH() macro. This allows to trace cgroup state transitions and is generally helpful for debugging the cgroup freezer code. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-04-20 01:03:08 +08:00
__entry->val = val;
),
cgroup: Trace event cgroup id fields should be u64 Various trace event fields that store cgroup IDs were declared as ints, but cgroup_id(() returns a u64 and the structures and associated TP_printk() calls were not updated to reflect this. Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID") Signed-off-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-12-02 00:56:58 +08:00
TP_printk("root=%d id=%llu level=%d path=%s val=%d",
cgroup: add tracing points for cgroup v2 freezer Add cgroup:cgroup_freeze and cgroup:cgroup_unfreeze events, which are using the existing cgroup tracing infrastructure. Add the cgroup_event event class, which is similar to the cgroup class, but contains an additional integer field to store a new value (the level field is dropped). Also add two tracing events: cgroup_notify_populated and cgroup_notify_frozen, which are raised in a generic way using the TRACE_CGROUP_PATH() macro. This allows to trace cgroup state transitions and is generally helpful for debugging the cgroup freezer code. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-04-20 01:03:08 +08:00
__entry->root, __entry->id, __entry->level, __get_str(path),
__entry->val)
);
DEFINE_EVENT(cgroup_event, cgroup_notify_populated,
TP_PROTO(struct cgroup *cgrp, const char *path, int val),
TP_ARGS(cgrp, path, val)
);
DEFINE_EVENT(cgroup_event, cgroup_notify_frozen,
TP_PROTO(struct cgroup *cgrp, const char *path, int val),
TP_ARGS(cgrp, path, val)
);
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
DECLARE_EVENT_CLASS(cgroup_rstat,
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
TP_ARGS(cgrp, cpu, contended),
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
TP_STRUCT__entry(
__field( int, root )
__field( int, level )
__field( u64, id )
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
__field( int, cpu )
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
__field( bool, contended )
),
TP_fast_assign(
__entry->root = cgrp->root->hierarchy_id;
__entry->id = cgroup_id(cgrp);
__entry->level = cgrp->level;
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
__entry->cpu = cpu;
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
__entry->contended = contended;
),
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
TP_printk("root=%d id=%llu level=%d cpu=%d lock contended:%d",
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
__entry->root, __entry->id, __entry->level,
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
__entry->cpu, __entry->contended)
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
);
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
/* Related to global: cgroup_rstat_lock */
cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints This commit enhances the ability to troubleshoot the global cgroup_rstat_lock by introducing wrapper helper functions for the lock along with associated tracepoints. Although global, the cgroup_rstat_lock helper APIs and tracepoints take arguments such as cgroup pointer and cpu_in_loop variable. This adjustment is made because flushing occurs per cgroup despite the lock being global. Hence, when troubleshooting, it's important to identify the relevant cgroup. The cpu_in_loop variable is necessary because the global lock may be released within the main flushing loop that traverses CPUs. In the tracepoints, the cpu_in_loop value is set to -1 when acquiring the main lock; otherwise, it denotes the CPU number processed last. The new feature in this patchset is detecting when lock is contended. The tracepoints are implemented with production in mind. For minimum overhead attach to cgroup:cgroup_rstat_lock_contended, which only gets activated when trylock detects lock is contended. A quick production check for issues could be done via this perf commands: perf record -g -e cgroup:cgroup_rstat_lock_contended Next natural question would be asking how long time do lock contenders wait for obtaining the lock. This can be answered by measuring the time between cgroup:cgroup_rstat_lock_contended and cgroup:cgroup_rstat_locked when args->contended is set. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); }' Extending with time spend holding the lock will be more expensive as this also looks at all the non-contended cases. Like this bpftrace script: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_lock_contended {@start[tid]=nsecs} tracepoint:cgroup:cgroup_rstat_locked { @locked[tid]=nsecs; if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);}} tracepoint:cgroup:cgroup_rstat_unlock { @locked_ns=hist(nsecs-@locked[tid]); delete(@locked[tid]);} interval:s:1 {time("%H:%M:%S "); print(@wait_ns);print(@locked_ns); }' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-17 01:51:26 +08:00
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_lock_contended,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_locked,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_unlock,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
cgroup/rstat: add cgroup_rstat_cpu_lock helpers and tracepoints This closely resembles helpers added for the global cgroup_rstat_lock in commit fc29e04ae1ad ("cgroup/rstat: add cgroup_rstat_lock helpers and tracepoints"). This is for the per CPU lock cgroup_rstat_cpu_lock. Based on production workloads, we observe the fast-path "update" function cgroup_rstat_updated() is invoked around 3 million times per sec, while the "flush" function cgroup_rstat_flush_locked(), walking each possible CPU, can see periodic spikes of 700 invocations/sec. For this reason, the tracepoints are split into normal and fastpath versions for this per-CPU lock. Making it feasible for production to continuously monitor the non-fastpath tracepoint to detect lock contention issues. The reason for monitoring is that lock disables IRQs which can disturb e.g. softirq processing on the local CPUs involved. When the global cgroup_rstat_lock stops disabling IRQs (e.g converted to a mutex), this per CPU lock becomes the next bottleneck that can introduce latency variations. A practical bpftrace script for monitoring contention latency: bpftrace -e ' tracepoint:cgroup:cgroup_rstat_cpu_lock_contended { @start[tid]=nsecs; @cnt[probe]=count()} tracepoint:cgroup:cgroup_rstat_cpu_locked { if (args->contended) { @wait_ns=hist(nsecs-@start[tid]); delete(@start[tid]);} @cnt[probe]=count()} interval:s:1 {time("%H:%M:%S "); print(@wait_ns); print(@cnt); clear(@cnt);}' Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-05-01 22:04:11 +08:00
/* Related to per CPU: cgroup_rstat_cpu_lock */
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_lock_contended,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_lock_contended_fastpath,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_locked,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_locked_fastpath,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_unlock,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_unlock_fastpath,
TP_PROTO(struct cgroup *cgrp, int cpu, bool contended),
TP_ARGS(cgrp, cpu, contended)
);
cgroup: add tracepoints for basic operations Debugging what goes wrong with cgroup setup can get hairy. Add tracepoints for cgroup hierarchy mount, cgroup creation/destruction and task migration operations for better visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2016-08-10 23:23:44 +08:00
#endif /* _TRACE_CGROUP_H */
/* This part must be outside protection */
#include <trace/define_trace.h>
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