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4 commits

Author SHA1 Message Date
Elliott Hughes
4c62e59fe6 Add epoll_pwait2().
I've also added doc comments for everything in <sys/epoll.h>.

I've also broken up the old "smoke" test (which was taking 2s on my
riscv64 qemu) to keep the total runtime for all the tests down to 200ms.

Test: treehugger
Change-Id: Icd939af51886fdf21432653a07373c1a0f26e422
2023-08-23 15:59:12 -07:00
Elliott Hughes
215baed16f De-pessimize SigSetConverter usage.
While looking at the disassembly for the epoll stuff I noticed that this
expands to quite a lot of code that the compiler can't optimize out for
LP64 (because it doesn't know that the "copy the argument into a local
and then use the local" bit isn't important).

There are two obvious options here. Something like this:
```
  int signalfd64(int fd, const sigset64_t* mask, int flags) {
    return __signalfd4(fd, mask, sizeof(*mask), flags);
  }

  int signalfd(int fd, const sigset_t* mask, int flags) {
  #if defined(__LP64__)
    return signalfd64(fd, mask, flags);
  #else
    SigSetConverter set = {.sigset = *mask};
    return signalfd64(fd, &set.sigset64, flags);
  #endif
  }
```
Or something like this:
```
  int signalfd64(int fd, const sigset64_t* mask, int flags) {
    return __signalfd4(fd, mask, sizeof(*mask), flags);
  }

  #if defined(__LP64__)
  __strong_alias(signalfd, signalfd64);
  #else
  int signalfd(int fd, const sigset_t* mask, int flags) {
    SigSetConverter set = {};
    set.sigset = *mask;
    return signalfd64(fd, &set.sigset64, flags);
  }
  #endif
```
The former is slightly more verbose, but seems a bit more obvious, so I
initially went with that. (The former is more verbose in the generated
code too, given that the latter expands to _no_ code, just another symbol
pointing to the same code address.)

Having done that, I realized that slight changes to the interface would
let clang optimize away most/all of the overhead for LP64 with the only
preprocessor hackery being in SigSetConverter itself.

I also pulled out the legacy bsd `int` conversions since they're only
used in two (secret!) functions, so it's clearer to just have a separate
union for them. While doing so, I suppressed those functions for
riscv64, since there's no reason to keep carrying that mistake forward.

posix_spawn() is another simple case that doesn't actually benefit from
SigSetConverter, so I've given that its own anonymous union too.

Test: treehugger
Change-Id: Iaf67486da40d40fc53ec69717c3492ab7ab81ad6
2023-07-19 12:20:07 -07:00
Josh Gao
a38331d833 fdtrack: add wrappers for epoll_create, epoll_create1.
Bug: https://issuetracker.google.com/154450436
Test: bionic-unit-tests
Change-Id: I6c881e5d67596c543526536541d5b8086e21d9e9
2020-04-29 17:21:16 -07:00
Elliott Hughes
5905d6f879 Add sigset64_t and accompanying functions.
This doesn't address `struct sigaction` and `sigaction`. That will
come later.

Bug: http://b/72493232
Test: ran tests
Change-Id: I4134346757ce3a4dac6feae413361cec16223386
2018-01-30 18:47:16 -08:00
Renamed from libc/bionic/epoll_pwait.cpp (Browse further)