Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
The setting and checking of 'done' contains a rare race where the signal handler setting 'done' is run after checking to break the loop, but before waiting in evlist__poll(). In this case, the main loop won't wake up until either another signal is sent, or the perf data fd causes a wake up. The following simple script can trigger this condition (but you might need to run it for several hours): for ((i = 0; i >= 0; i++)) ; do echo "Loop $i" delay=$(echo "scale=4; 0.1 * $RANDOM/32768" | bc) ./perf record -- sleep 30000000 >/dev/null& pid=$! sleep $delay kill -TERM $pid echo "PID $pid" wait $pid done At some point, the loop will stall. Adding logging, even though perf has received the SIGTERM and set 'done = 1', perf will remain sleeping until a second signal is sent. Committer notes: Make this dependent on HAVE_EVENTFD_SUPPORT, so that we continue building on older systems without the eventfd syscall. Signed-off-by: Anand K Mistry <amistry@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20200513122012.v3.1.I4d7421c6bbb1f83ea58419082481082e19097841@changeid Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| 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 | ||
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.