b92675f4a9
While tracing a program that calls isatty(3), I noticed that strace
reported TCGETS for the request argument of the underlying ioctl(2)
syscall while perf trace reported TCSETS. strace is corrrect. The bug in
perf was due to the tty ioctl beauty table starting at 0x5400 rather
than 0x5401.
Committer testing:
Using augmented_raw_syscalls.o and settings to make 'perf trace'
use strace formatting, i.e. with this in ~/.perfconfig
# cat ~/.perfconfig
[trace]
add_events = /home/acme/git/linux/tools/perf/examples/bpf/augmented_raw_syscalls.c
show_zeros = yes
show_duration = no
no_inherit = yes
show_timestamp = no
show_arg_names = no
args_alignment = 40
show_prefix = yes
# strace -e ioctl stty > /dev/null
ioctl(0, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TIOCGWINSZ, 0x7fff8a9b0860) = -1 ENOTTY (Inappropriate ioctl for device)
ioctl(1, TCGETS, 0x7fff8a9b0540) = -1 ENOTTY (Inappropriate ioctl for device)
+++ exited with 0 +++
#
Before:
# perf trace -e ioctl stty > /dev/null
ioctl(0, TCSETS, 0x7fff2cf79f20) = 0
ioctl(1, TIOCSWINSZ, 0x7fff2cf79f40) = -1 ENOTTY (Inappropriate ioctl for device)
ioctl(1, TCSETS, 0x7fff2cf79c20) = -1 ENOTTY (Inappropriate ioctl for device)
#
After:
# perf trace -e ioctl stty > /dev/null
ioctl(0, TCGETS, 0x7ffed0763920) = 0
ioctl(1, TIOCGWINSZ, 0x7ffed0763940) = -1 ENOTTY (Inappropriate ioctl for device)
ioctl(1, TCGETS, 0x7ffed0763620) = -1 ENOTTY (Inappropriate ioctl for device)
#
Signed-off-by: Benjamin Peterson <benjamin@python.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes:
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.