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| author | Sean Bright <sean.bright@gmail.com> | 2017-04-17 20:06:10 -0400 |
|---|---|---|
| committer | Sean Bright <sean.bright@gmail.com> | 2017-04-24 12:46:27 -0400 |
| commit | cea3742c549a3c31621d2d29a1b78b42211e01d0 (patch) | |
| tree | 10d3b39a433741922041fdbe0608d22e1905f1f9 /configure.ac | |
| parent | dac4442cdd787b58035fcd13d51abbf50a4d7cb3 (diff) | |
core: Use eventfd for alert pipes on Linux when possible
The primary win of switching to eventfd when possible is that it only
uses a single file descriptor while pipe() will use two. This means for
each bridge channel we're reducing the number of required file
descriptors by 1, and - if you're using timerfd - we also now have 1
less file descriptor per Asterisk channel.
The API is not ideal (passing int arrays), but this is the cleanest
approach I could come up with to maintain API/ABI.
I've also removed what I believe to be an erroneous code block that
checked the non-blocking flag on the pipe ends for each read. If the
file descriptor is 'losing' its non-blocking mode, it is because of a
bug somewhere else in our code.
In my testing I haven't seen any measurable difference in performance.
Change-Id: Iff0fb1573e7f7a187d5211ddc60aa8f3da3edb1d
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/configure.ac b/configure.ac index 0458ce1a7..bf98ad386 100644 --- a/configure.ac +++ b/configure.ac @@ -1098,6 +1098,15 @@ if test "${ac_cv_have_variable_fdset}x" = "0x"; then AC_DEFINE([CONFIGURE_RAN_AS_ROOT], 1, [Some configure tests will unexpectedly fail if configure is run by a non-root user. These may be able to be tested at runtime.])) fi +AC_MSG_CHECKING([if we have usable eventfd support]) +AC_RUN_IFELSE( + [AC_LANG_PROGRAM([#include <sys/eventfd.h>], + [return eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE) == -1;])], + AC_MSG_RESULT(yes) + AC_DEFINE([HAVE_EVENTFD], 1, [Define to 1 if your system supports eventfd and the EFD_NONBLOCK and EFD_SEMAPHORE flags.]), + AC_MSG_RESULT(no) +) + AST_GCC_ATTRIBUTE(pure) AST_GCC_ATTRIBUTE(malloc) AST_GCC_ATTRIBUTE(const) |