Go to file
Steven Rostedt (VMware) 883b4aee4d tracing: Add trace_event helper macros __string_len() and __assign_str_len()
There's a few cases that a string that is to be recorded in a trace event,
does not have a terminating 'nul' character, and instead, the tracepoint
passes in the length of the string to record.

Add two helper macros to the trace event code that lets this work easier,
than tricks with "%.*s" logic.

  __string_len() which is similar to __string() for declaration, but takes a
                 length argument.

  __assign_str_len() which is similar to __assign_str() for assiging the
                 string, but it too takes a length argument.

Note, the TRACE_EVENT() macro will allocate the location on the ring
buffer to 'len + 1', that will be used to store the string into. It is a
requirement that the 'len' used for this is a most the length of the
string being recorded.

This string can still use __get_str() just like strings created with
__string() can use to retrieve the string.

Link: https://lore.kernel.org/linux-nfs/20210513105018.7539996a@gandalf.local.home/

Tested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-08-17 11:47:52 -04:00
Documentation ARM: 2021-08-15 06:21:30 -10:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
arch powerpc fixes for 5.14 #5 2021-08-15 06:57:43 -10:00
block block-5.14-2021-08-13 2021-08-13 13:36:42 -10:00
certs Kbuild updates for v5.13 (2nd) 2021-05-08 10:00:11 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-07-09 11:00:44 -07:00
drivers A set of fixes for PCI/MSI and x86 interrupt startup: 2021-08-15 06:49:40 -10:00
fs NFSD: Batch release pages during splice read 2021-08-17 11:47:52 -04:00
include tracing: Add trace_event helper macros __string_len() and __assign_str_len() 2021-08-17 11:47:52 -04:00
init Revert "mm/slub: use stackdepot to save stack trace in objects" 2021-07-17 13:27:00 -07:00
ipc Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
kernel A set of fixes for PCI/MSI and x86 interrupt startup: 2021-08-15 06:49:40 -10:00
lib lib: use PFN_PHYS() in devmem_is_allowed() 2021-08-13 14:09:32 -10:00
mm mm/memcg: fix incorrect flushing of lruvec data in obj_stock 2021-08-13 14:09:32 -10:00
net SUNRPC: Add svc_rqst_replace_page() API 2021-08-17 11:47:52 -04:00
samples tracing: Add trace_event helper macros __string_len() and __assign_str_len() 2021-08-17 11:47:52 -04:00
scripts Kbuild fixes for v5.14 (2nd) 2021-08-07 10:03:02 -07:00
security bpf: Add lockdown check for probe_write_user helper 2021-08-10 10:10:10 +02:00
sound sound fixes for 5.14-rc6 2021-08-12 07:06:40 -10:00
tools libnvdimm fixes for v5.14-rc6 2021-08-14 19:46:39 -10:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: Do not leak memory for duplicate debugfs directories 2021-08-04 06:02:03 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap m68k updates for v5.14 2021-06-28 14:01:03 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Networking fixes for 5.14-rc6, including fixes from netfilter, bpf, 2021-08-12 16:24:03 -10:00
Makefile Linux 5.14-rc6 2021-08-15 13:40:53 -10:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

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.