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https://gitlab.freedesktop.org/pulseaudio/pulseaudio.git
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d4ff4adce2
The original atomic implementation in pulseaudio based on libatomic stated that the intent was to use full memory barriers. According to [1], the load and store implementation based on gcc builtins matches sequential consistent (i.e. full memory barrier) load and store ordering only for x86. I observed random crashes in client applications using memfd srbchannel transport on an armv8-aarch64 platform (cortex-a57). In all those crashes the first read on the pstream descriptor (the size field) was wrong and looked like it contained old data. I boiled the relevant parts of the srbchannel implementation down to a simple test case and could observe random test failures. So I figured that the atomic implementation was broken for armv8 with respect to cross-cpu memory access ordering consistency. In order to come up with a minimal fix, I used the newer __atomic_load_n/__atomic_store_n builtins from gcc. With aarch64-linux-gnu-gcc (Linaro GCC 7.3-2018.05) 7.3.1 20180425 they compile to ldar and stlxr on arm64, which is correct according to [1] and [2]. The other atomic operations based on __sync builtins don't need to be touched since they already are of the full memory barrier variety. [1] https://www.cl.cam.ac.uk/~pes20/cpp/cpp0xmappings.html [2] <https://community.arm.com/developer/ip-products/processors /b/processors-ip-blog/posts/armv8-a-architecture-2016-additions> |
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| m4 | ||
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| scripts | ||
| shell-completion | ||
| src | ||
| vala | ||
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| .mailmap | ||
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| autogen.sh | ||
| bootstrap.sh | ||
| CODE_OF_CONDUCT.md | ||
| configure.ac | ||
| git-version-gen | ||
| GPL | ||
| LGPL | ||
| libpulse-mainloop-glib.pc.in | ||
| libpulse-simple.pc.in | ||
| libpulse.pc.in | ||
| LICENSE | ||
| Makefile.am | ||
| meson.build | ||
| meson_options.txt | ||
| NEWS | ||
| orc.mak | ||
| PROTOCOL | ||
| pulseaudio-text.svg | ||
| pulseaudio.supp | ||
| pulseaudio.svg | ||
| PulseAudioConfig.cmake.in | ||
| PulseAudioConfigVersion.cmake.in | ||
| README | ||
| todo | ||
PULSEAUDIO SOUND SERVER
WEB SITE:
http://pulseaudio.org/
GIT:
https://gitlab.freedesktop.org/pulseaudio/pulseaudio.git
GitLab:
https://gitlab.freedesktop.org/pulseaudio/pulseaudio
MAILING LIST:
http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss
GIT COMMITS MAILING LIST:
http://lists.freedesktop.org/mailman/listinfo/pulseaudio-commits
TRAC/BUGZILLA TICKET CHANGES MAILING LIST:
http://lists.freedesktop.org/mailman/listinfo/pulseaudio-bugs
IRC:
#pulseaudio on irc.freenode.org
FRESHMEAT:
http://freshmeat.net/projects/pulseaudio/
OHLOH:
http://www.ohloh.net/projects/4038
AUTHORS:
Several
HACKING:
In order to run pulseaudio from the build dir __OPTIMIZE__ should be
disabled (look at src/pulsecore/core-util.h::pa_run_from_build_tree()),
this can be done by passing "CFLAGS=-O0" to the configure script:
./autogen.sh
CFLAGS="-ggdb3 -O0" LDFLAGS="-ggdb3" ./configure
make
./src/pulseaudio -n -F src/default.pa -p $(pwd)/src/
SPELLING:
PulseAudio