workqueue: Fix type of cpu in trace event

The trace event "workqueue_queue_work" use unsigned int type for
req_cpu, cpu. This casue confusing cpu number like below log.

$ cat /sys/kernel/debug/tracing/trace
cat-317 [001] ...: workqueue_queue_work: ... req_cpu=8192 cpu=4294967295

So, change unsigned type to signed type in the trace event. After
applying this patch, cpu number will be printed as -1 instead of
4294967295 as folllows.

$ cat /sys/kernel/debug/tracing/trace
cat-1338 [002] ...: workqueue_queue_work: ... req_cpu=8192 cpu=-1

Cc: Baik Song An <bsahn@etri.re.kr>
Cc: Hong Yeon Kim <kimhy@etri.re.kr>
Cc: Taeung Song <taeung@reallinux.co.kr>
Cc: linuxgeek@linuxgeek.io
Signed-off-by: Wonhyuk Yang <vvghjk1234@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

workqueue/tracing: Copy workqueue name to buffer in trace event

The trace event "workqueue_queue_work" references an unsafe string in
dereferencing the name of the workqueue. As the name is allocated, it
could later be freed, and the pointer to that string could stay on the
tracing buffer. If the trace buffer is read after the string is freed, it
will reference an unsafe pointer.

I added a new verifier to make sure that all strings referenced in the
output of the trace buffer is safe to read and this triggered on the
workqueue_queue_work trace event:

workqueue_queue_work: work struct=00000000b2b235c7 function=gc_worker workqueue=(0xffff888100051160:events_power_efficient)[UNSAFE-MEMORY] req_cpu=256 cpu=1
workqueue_queue_work: work struct=00000000c344caec function=flush_to_ldisc workqueue=(0xffff888100054d60:events_unbound)[UNSAFE-MEMORY] req_cpu=256 cpu=4294967295
workqueue_queue_work: work struct=00000000b2b235c7 function=gc_worker workqueue=(0xffff888100051160:events_power_efficient)[UNSAFE-MEMORY] req_cpu=256 cpu=1
workqueue_queue_work: work struct=000000000b238b3f function=vmstat_update workqueue=(0xffff8881000c3760:mm_percpu_wq)[UNSAFE-MEMORY] req_cpu=1 cpu=1

Also, if this event is read via a user space application like perf or
trace-cmd, the name would only be an address and useless information:

workqueue_queue_work: work struct=0xffff953f80b4b918 function=disk_events_workfn workqueue=ffff953f8005d378 req_cpu=8192 cpu=5

Cc: Zqiang <qiang.zhang@windriver.com>
Cc: Tejun Heo <tj@kernel.org>
Fixes: 7bf9c4a88e3e3 ("workqueue: tracing the name of the workqueue instead of it's address")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

workqueue: tracing the name of the workqueue instead of it's address

This patch tracing workqueue name instead of it's address, the
new format is as follows.

workqueue_queue_work: work struct=0000000084e3df56 function=
drm_fb_helper_dirty_work workqueue=events req_cpu=256 cpu=1

This tell us to know which workqueue our work is queued.

Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

workqueue: remove workqueue_work event class

The trace event class workqueue_work now has only one consumer, so get
rid of it. No functional change.

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>

workqueue: add worker function to workqueue_execute_end tracepoint

It's surprising that workqueue_execute_end includes only the work when
its counterpart workqueue_execute_start has both the work and the worker
function.

You can't set a tracing filter or trigger based on the function, and
postprocessing scripts interested in specific functions are harder to
write since they have to remember the work from _start and match it up
with the same field in _end.

Add the function name, taking care to use the copy stashed in the
worker since the work is no longer safe to touch.

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>

treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively

%pF and %pf are functionally equivalent to %pS and %ps conversion
specifiers. The former are deprecated, therefore switch the current users
to use the preferred variant.

The changes have been produced by the following command:

git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done

And verifying the result.

Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
Cc: linux-pci@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-mm@kvack.org
Cc: ceph-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: David Sterba <dsterba@suse.com> (for btrfs)
Acked-by: Mike Rapoport <rppt@linux.ibm.com> (for mm/memblock.c)
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (for drivers/pci)
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>

tracing: Add missing forward declaration

Without this forward declaration compile may fail if this header is
included only for registering other probe event without struct
pool_workqueue.

Link: http://lkml.kernel.org/r/20180416023626.139915-1-cwahbong@google.com

Reviewed-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Ahbong Chang <cwahbong@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

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>

workqueue: rename cpu_workqueue to pool_workqueue

workqueue has moved away from global_cwqs to worker_pools and with the
scheduled custom worker pools, wforkqueues will be associated with
pools which don't have anything to do with CPUs. The workqueue code
went through significant amount of changes recently and mass renaming
isn't likely to hurt much additionally. Let's replace 'cpu' with
'pool' so that it reflects the current design.

* s/struct cpu_workqueue_struct/struct pool_workqueue/
* s/cpu_wq/pool_wq/
* s/cwq/pwq/

This patch is purely cosmetic.

Signed-off-by: Tejun Heo <tj@kernel.org>

workqueue: move global_cwq->cpu to worker_pool

Move gcwq->cpu to pool->cpu. This introduces a couple places where
gcwq->pools[0].cpu is used. These will soon go away as gcwq is
further reduced.

This is part of an effort to remove global_cwq and make worker_pool
the top level abstraction, which in turn will help implementing worker
pools with user-specified attributes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>

workqueue: factor out worker_pool from global_cwq

Move worklist and all worker management fields from global_cwq into
the new struct worker_pool. worker_pool points back to the containing
gcwq. worker and cpu_workqueue_struct are updated to point to
worker_pool instead of gcwq too.

This change is mechanical and doesn't introduce any functional
difference other than rearranging of fields and an added level of
indirection in some places. This is to prepare for multiple pools per
gcwq.

v2: Comment typo fixes as suggested by Namhyung.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>

workqueue: Fix workqueue_execute_end() comment

workqueue_execute_end() is called after the callback function,
not before.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

workqueue: add queue_work and activate_work trace points

These two tracepoints allow tracking when and how a work is queued and
activated. This patch is based on Frederic's patch to add queue_work
trace point.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>

workqueue: prepare for more tracepoints

Define workqueue_work event class and use it for workqueue_execute_end
trace point. Also, move trace/events/workqueue.h include downwards
such that all struct definitions are visible to it. This is to
prepare for more tracepoints and doesn't cause any functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>

workqueue: Add basic tracepoints to track workqueue execution

With the introduction of the new unified work queue thread pools,
we lost one feature: It's no longer possible to know which worker
is causing the CPU to wake out of idle. The result is that PowerTOP
now reports a lot of "kworker/a:b" instead of more readable results.

This patch adds a pair of tracepoints to the new workqueue code,
similar in style to the timer/hrtimer tracepoints.

With this pair of tracepoints, the next PowerTOP can correctly
report which work item caused the wakeup (and how long it took):

Interrupt (43) i915 time 3.51ms wakeups 141
Work ieee80211_iface_work time 0.81ms wakeups 29
Work do_dbs_timer time 0.55ms wakeups 24
Process Xorg time 21.36ms wakeups 4
Timer sched_rt_period_timer time 0.01ms wakeups 1

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

workqueue: temporarily remove workqueue tracing

Strip tracing code from workqueue and remove workqueue tracing. This
is temporary measure till concurrency managed workqueue is complete.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>

tracing: Convert some workqueue events to DEFINE_EVENT

Use DECLARE_EVENT_CLASS to remove duplicate code:

text data bss dec hex filename
13171 800 72 14043 36db kernel/workqueue.o.old
12243 800 68 13111 3337 kernel/workqueue.o

Two events are converted:

workqueue: workqueue_insertion, workqueue_execution

No change in functionality.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E289F.5010104@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tracing/workqueue: Use %pf in workqueue trace events

Using %pf instead of %pF supresses printing of the function offset
which will always be 0 in the case of worklet functions.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090922024033.GB31801@kryten>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

tracing/events: Move TRACE_SYSTEM outside of include guard

If TRACE_INCLDUE_FILE is defined, <trace/events/TRACE_INCLUDE_FILE.h>
will be included and compiled, otherwise it will be
<trace/events/TRACE_SYSTEM.h>

So TRACE_SYSTEM should be defined outside of #if proctection,
just like TRACE_INCLUDE_FILE.

Imaging this scenario:

#include <trace/events/foo.h>
-> TRACE_SYSTEM == foo
...
#include <trace/events/bar.h>
-> TRACE_SYSTEM == bar
...
#define CREATE_TRACE_POINTS
#include <trace/events/foo.h>
-> TRACE_SYSTEM == bar !!!

and then bar.h will be included and compiled.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A5A9CF1.2010007@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

ftrace, workqueuetrace: make workqueue tracepoints use TRACE_EVENT macro

v3: zhaolei@cn.fujitsu.com: Change TRACE_EVENT definition to new format
introduced by Steven Rostedt: consolidate trace and trace_event headers
v2: kosaki@jp.fujitsu.com: print the function names instead of addr, and zap
the work addr
v1: zhaolei@cn.fujitsu.com: Make workqueue tracepoints use TRACE_EVENT macro

TRACE_EVENT is a more generic way to define tracepoints.
Doing so adds these new capabilities to the tracepoints:

- zero-copy and per-cpu splice() tracing
- binary tracing without printf overhead
- structured logging records exposed under /debug/tracing/events
- trace events embedded in function tracer output and other plugins
- user-defined, per tracepoint filter expressions

Then, this patch converts DEFINE_TRACE to TRACE_EVENT in workqueue related
tracepoints.

[ Impact: expand workqueue tracer to events tracing ]

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>