-# From the sched_setaffinity(2)'s man page:
-# ~~~~
-# The CPU affinity system calls were introduced in Linux kernel 2.5.8.
-# The library interfaces were introduced in glibc 2.3. Initially, the
-# glibc interfaces included a cpusetsize argument. In glibc 2.3.3,
-# the cpuset size argument was removed, but this argument was
-# restored in glibc 2.3.4.
-# ~~~~
-
-# In addition to that, some vendors ported the system call to 2.4
-# kernels.
-
-# Furthermore, when the function first appeared, the MASK argument was
-# an unsigned long pointer, while later it was made into a cpu_set_t
-# pointer. Systems that have the cpu_set_t version also should have
-# the CPU_ZERO, CPU_SET, etc. macros.
-
-# All this mess means we have to cater for at least 3 different
-# sched_setaffinity prototypes:
-
-# ~~~~
-# int sched_setaffinity (pid_t pid, unsigned int len, unsigned long *mask);
-# int sched_setaffinity (pid_t __pid, size_t __cpusetsize, const cpu_set_t *__cpuset);
-# int sched_setaffinity (pid_t __pid, const cpu_set_t *__mask);
-# ~~~~
-
-AC_CHECK_TYPES([cpu_set_t],
- [have_cpu_set_t="yes"],
- [have_cpu_set_t="no"],
- [#include <sched.h>])
-
-# Confirm that we have CPU_ZERO, and it actually works.
-AC_MSG_CHECKING([whether CPU_ZERO works])
-AH_TEMPLATE([HAVE_CPU_ZERO], [Defined to 1 if we have CPU_ZERO and it works])
-AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
- #include <sched.h>
- int main()
- {
- cpu_set_t foo; CPU_ZERO(&foo);
- return 0;
- }
- ]])
-],[
- AC_DEFINE(HAVE_CPU_ZERO, 1)
- AC_MSG_RESULT([yes])
-],[
- AC_MSG_RESULT([no])
-])
-
-# Confirm that we have CPU_SET, and it actually works.
-AC_MSG_CHECKING([whether CPU_SET works])
-AH_TEMPLATE([HAVE_CPU_SET], [Defined to 1 if we have CPU_SET and it works])
-AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
- #include <sched.h>
- int main()
- {
- cpu_set_t foo; CPU_SET(0, &foo);
- return 0;
- }
- ]])
-],[
- AC_DEFINE(HAVE_CPU_SET, 1)
- AC_MSG_RESULT([yes])
-],[
- AC_MSG_RESULT([no])
-])
-
-# First check if the function is available at all.
-AC_CHECK_FUNCS([sched_setaffinity],[
- # Okay, we have it. Check if also have cpu_set_t. If we don't,
- # then we have the first version using unsigned long, and no
- # CPU_ZERO, etc. macros. If we do have cpu_set_t, we may have the
- # version with 2 or 3 arguments. In that case, CPU_ZERO, etc.,
- # should also be present, but we confirm nonetheless.
-
- AS_IF([test "x$have_cpu_set_t" = "xyes"], [
- # We do have it.
- # Check how many arguments does sched_setaffinity take.
- # Should be 3 or 2.
- AC_MSG_CHECKING([how many arguments sched_setaffinity takes])
- AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
- #include <sched.h>
- int main()
- {
- cpu_set_t foo;
- sched_setaffinity(0, sizeof (foo), &foo);
- return 0;
- }
- ]])
- ],
- [sched_set_affinity_args=3],
- [sched_set_affinity_args=2])
- AC_DEFINE_UNQUOTED(SCHED_SETAFFINITY_ARGS,
- $sched_set_affinity_args,
- [Defined to sched_setaffinity's number of arguments.])
- AC_MSG_RESULT([$sched_set_affinity_args])
- ],[
- # No cpu_set_t, always 3 args.
- AC_DEFINE(SCHED_SETAFFINITY_ARGS, 3)
- ])
-])
-
-