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authorHenning Heinold <heinold@inf.fu-berlin.de>2011-06-04 21:21:41 +0200
committerBernhard Reutner-Fischer <rep.dot.nop@gmail.com>2011-11-07 20:57:02 +0100
commit19dd090a0f68765db87990ef8eda9bf77bb29581 (patch)
treef210bb330d8b3dda2bcc345a80ce476bd41e1a69 /libc/sysdeps/linux/x86_64
parent0c7690f6a5d6e073052ee6487f768289db3a58f7 (diff)
libc: flesh out linux scheduler functions
Most stuff was taken from the eglibc. Signed-off-by: Henning Heinold <heinold@inf.fu-berlin.de> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Diffstat (limited to 'libc/sysdeps/linux/x86_64')
-rw-r--r--libc/sysdeps/linux/x86_64/Makefile.arch7
-rw-r--r--libc/sysdeps/linux/x86_64/sched_getcpu.S72
2 files changed, 79 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/x86_64/Makefile.arch b/libc/sysdeps/linux/x86_64/Makefile.arch
index de7ce7285..0d14650ff 100644
--- a/libc/sysdeps/linux/x86_64/Makefile.arch
+++ b/libc/sysdeps/linux/x86_64/Makefile.arch
@@ -17,3 +17,10 @@ SSRC := \
ifneq ($(UCLIBC_HAS_THREADS_NATIVE),y)
SSRC += vfork.S clone.S
endif
+
+ifeq ($(UCLIBC_LINUX_SPECIFIC),y)
+ARCH_OBJ_FILTEROUT = sched_getcpu.c
+ifeq ($(UCLIBC_HAS_TLS),y)
+SSRC += sched_getcpu.S
+endif
+endif
diff --git a/libc/sysdeps/linux/x86_64/sched_getcpu.S b/libc/sysdeps/linux/x86_64/sched_getcpu.S
new file mode 100644
index 000000000..592bcdbdf
--- /dev/null
+++ b/libc/sysdeps/linux/x86_64/sched_getcpu.S
@@ -0,0 +1,72 @@
+/* Copyright (C) 2007, 2011 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include <tls.h>
+#define _ERRNO_H 1
+#include <bits/errno.h>
+#include <bits/kernel-features.h>
+
+/* For the calculation see asm/vsyscall.h. */
+#define VSYSCALL_ADDR_vgetcpu 0xffffffffff600800
+
+
+ENTRY (sched_getcpu)
+ /* Align stack and create local variable for result. */
+ sub $0x8, %rsp
+ cfi_adjust_cfa_offset(8)
+
+ movq %rsp, %rdi
+ xorl %esi, %esi
+ movl $VGETCPU_CACHE_OFFSET, %edx
+ addq %fs:0, %rdx
+
+#ifdef SHARED
+ movq __vdso_getcpu(%rip), %rax
+ PTR_DEMANGLE (%rax)
+ callq *%rax
+#else
+# ifdef __NR_getcpu
+ movl $__NR_getcpu, %eax
+ syscall
+# ifndef __ASSUME_GETCPU_SYSCALL
+ cmpq $-ENOSYS, %rax
+ jne 1f
+# endif
+# endif
+# ifndef __ASSUME_GETCPU_SYSCALL
+ movq $VSYSCALL_ADDR_vgetcpu, %rax
+ callq *%rax
+1:
+# else
+# ifndef __NR_getcpu
+# error "cannot happen"
+# endif
+# endif
+#endif
+
+ cmpq $-4095, %rax
+ jae SYSCALL_ERROR_LABEL
+
+ movl (%rsp), %eax
+
+L(pseudo_end):
+ add $0x8, %rsp
+ cfi_adjust_cfa_offset(-8)
+ ret
+PSEUDO_END(sched_getcpu)