45e31869cc
When tracepoints use __print_symbolic to print textual representation of
a value that comes from an ENUM each enum value needs to be exported
to user space so that user space tools can convert the binary value
data to the trings as user space does not know what those enums are
about.
Doing a trace-cmd record && trace-cmd report currently results in:
kworker/u8:1-61 [000] 66.299527:
btrfs_flush_space: 5302ee13-c65e-45bb-98ef-8fe3835bd943:
state=3(0x3) flags=4(METADATA) num_bytes=2621440 ret=0
I.e state is not translated to its symbolic counterpart. With this patch
applied the output is:
fio-370 [002] 56.762402: btrfs_trigger_flush: d04cd7ac-38e2-452f-a7f5-8157529fd5f0:
preempt: flush=3(BTRFS_RESERVE_FLUSH_ALL) flags=4(METADATA) bytes=655360
See also 190f0b76ca ("mm: tracing: Export enums in tracepoints to user
space").
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.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.