--- /dev/null
+/*
+ This file is a part of libcds - Concurrent Data Structures library
+
+ (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2017
+
+ Source code repo: http://github.com/khizmax/libcds/
+ Download: http://sourceforge.net/projects/libcds/files/
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef CDSLIB_OS_LINUX_TOPOLOGY_H
+#define CDSLIB_OS_LINUX_TOPOLOGY_H
+
+#ifndef CDSLIB_OS_TOPOLOGY_H
+# error "<cds/os/topology.h> must be included instead"
+#endif
+
+#include <cds/details/defs.h>
+#include <cds/threading/model.h>
+
+#include <sys/syscall.h>
+#include <sched.h>
+
+namespace cds { namespace OS {
+ /// Linux-specific wrappers
+ inline namespace Linux {
+
+ /// System topology
+ /**
+ The implementation assumes that processor IDs are in numerical order
+ from 0 to N - 1, where N - count of processor in the system
+ */
+ struct topology {
+ private:
+ //@cond
+ static unsigned int s_nProcessorCount;
+ //@endcond
+ public:
+
+ /// Logical processor count for the system
+ static unsigned int processor_count()
+ {
+ return s_nProcessorCount;
+ }
+
+ /// Get current processor number
+ /**
+ Caveat: \p current_processor calls system \p sched_getcpu function
+ that may not be defined for target system (\p sched_getcpu is available since glibc 2.6).
+ If \p sched_getcpu is not defined the function emulates "current processor number" using
+ thread-specific data. You may manually disable the \p sched_getcpu usage compiling with
+ <tt>-DCDS_LINUX_NO_sched_getcpu</tt>.
+ */
+ static unsigned int current_processor()
+ {
+ // Compile libcds with -DCDS_LINUX_NO_sched_getcpu if your linux does not have sched_getcpu (glibc version less than 2.6)
+# if !defined(CDS_LINUX_NO_sched_getcpu) && defined(SYS_getcpu)
+ int nProcessor = ::sched_getcpu();
+ return nProcessor == -1 ? 0 : (unsigned int) nProcessor;
+# else
+ // Use fake "current processor number" assigned for current thread
+ return (unsigned int) threading::Manager::fake_current_processor();
+
+ /*
+ Another way (for x86/amd64 only)
+
+ Using cpuid and APIC ID (http://www.scss.tcd.ie/Jeremy.Jones/GetCurrentProcessorNumberXP.htm)
+ for x86 and amd64
+ {
+ _asm {mov eax, 1}
+ _asm {cpuid}
+ _asm {shr ebx, 24}
+ _asm {mov eax, ebx}
+ }
+ However:
+ - cpuid is full sync barrier
+ - it is only for x86/amd64 architecture
+ */
+# endif
+ }
+
+ /// Synonym for \ref current_processor
+ static unsigned int native_current_processor()
+ {
+ return current_processor();
+ }
+
+ //@cond
+ static void init();
+ static void fini();
+ //@endcond
+ };
+ } // namespace Linux
+
+}} // namespace cds::OS
+
+#endif // #ifndef CDSLIB_OS_LINUX_TOPOLOGY_H