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The 'perf kwork' tool is used to trace time properties of kernel work
(such as irq, softirq, and workqueue), including runtime, latency, and
timehist, using the infrastructure in the perf tools to allow tracing
extra targets.
This is the first commit to reuse the 'perf record' framework code to
implement a simple record function, kwork is not supported currently.
Test cases:
# perf
usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]
The most commonly used perf commands are:
<SNIP>
iostat Show I/O performance metrics
kallsyms Searches running kernel for symbols
kmem Tool to trace/measure kernel memory properties
kvm Tool to trace/measure kvm guest os
kwork Tool to trace/measure kernel work properties (latencies)
list List all symbolic event types
lock Analyze lock events
mem Profile memory accesses
record Run a command and record its profile into perf.data
<SNIP>
See 'perf help COMMAND' for more information on a specific command.
# perf kwork
Usage: perf kwork [<options>] {record}
-D, --dump-raw-trace dump raw trace in ASCII
-f, --force don't complain, do it
-k, --kwork <kwork> list of kwork to profile
-v, --verbose be more verbose (show symbol address, etc)
# perf kwork record -- sleep 1
[ perf record: Woken up 0 times to write data ]
[ perf record: Captured and wrote 1.787 MB perf.data ]
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220709015033.38326-2-yangjihong1@huawei.com
[ Add {} for multiline if blocks ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.