kernel-ark/include/asm-um
Jeff Dike 3c91735099 [PATCH] uml: thread creation tidying
fork on UML has always somewhat subtle.  The underlying cause has been the
need to initialize a stack for the new process.  The only portable way to
initialize a new stack is to set it as the alternate signal stack and take a
signal.  The signal handler does whatever initialization is needed and jumps
back to the original stack, where the fork processing is finished.  The basic
context switching mechanism is a jmp_buf for each process.  You switch to a
new process by longjmping to its jmp_buf.

Now that UML has its own implementation of setjmp and longjmp, and I can poke
around inside a jmp_buf without fear that libc will change the structure, a
much simpler mechanism is possible.  The jmpbuf can simply be initialized by
hand.

This eliminates -
	the need to set up and remove the alternate signal stack
	sending and handling a signal
	the signal blocking needed around the stack switching, since
there is no stack switching
	setting up the jmp_buf needed to jump back to the original
stack after the new one is set up

In addition, since jmp_buf is now defined by UML, and not by libc, it can be
embedded in the thread struct.  This makes it unnecessary to have it exist on
the stack, where it used to be.  It also simplifies interfaces, since the
switch jmp_buf used to be a void * inside the thread struct, and functions
which took it as an argument needed to define a jmp_buf variable and assign it
from the void *.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:16 -07:00
..
a.out.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
alternative-asm.i [PATCH] i386: Redo semaphore and rwlock assembly helpers 2006-09-26 10:52:29 +02:00
alternative.h [PATCH] x86: SMP alternatives 2006-03-23 07:38:04 -08:00
apic.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
archparam-i386.h [PATCH] uml: s390 preparation, elf.h 2005-05-05 16:36:37 -07:00
archparam-ppc.h [PATCH] uml: s390 preparation, elf.h 2005-05-05 16:36:37 -07:00
archparam-x86_64.h [PATCH] uml: s390 preparation, elf.h 2005-05-05 16:36:37 -07:00
atomic.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
auxvec.h [PATCH] auxiliary vector cleanups 2005-09-07 16:57:21 -07:00
bitops.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
boot.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
bug.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
bugs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
byteorder.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cache.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
cacheflush.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
calling.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
checksum.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cobalt.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
common.lds.S [PATCH] uml: fix oops related to exception table 2005-05-01 08:58:53 -07:00
cpufeature.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cputime.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
current.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
delay.h [PATCH] uml: s390 preparation, delay moved to arch 2005-05-05 16:36:38 -07:00
desc.h [PATCH] uml: implement {get,set}_thread_area for i386 2006-03-31 12:18:52 -08:00
div64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dma-mapping.h [PATCH] gfp_t: dma-mapping (simple cases) 2005-10-28 08:16:49 -07:00
dma.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dwarf2.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
elf-i386.h [PATCH] uml: small fixes left over from rc4 2005-05-20 15:48:17 -07:00
elf-ppc.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
elf-x86_64.h [PATCH] uml: small fixes left over from rc4 2005-05-20 15:48:17 -07:00
emergency-restart.h [PATCH] Add emergency_restart() 2005-07-26 14:35:41 -07:00
errno.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fcntl.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fixmap.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
floppy.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
frame.i [PATCH] i386: Redo semaphore and rwlock assembly helpers 2006-09-26 10:52:29 +02:00
futex.h [PATCH] consolidate asm/futex.h 2006-01-08 20:13:39 -08:00
hardirq.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
highmem.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
host_ldt-i386.h [PATCH] uml: split ldt.h in arch-independent and arch-dependant code 2006-03-31 12:18:51 -08:00
host_ldt-x86_64.h [PATCH] uml: split ldt.h in arch-independent and arch-dependant code 2006-03-31 12:18:51 -08:00
hw_irq.h [PATCH] genirq: add ->retrigger() irq op to consolidate hw_irq_resend() 2006-06-29 10:26:23 -07:00
ide.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
io.h [PATCH] uml: add __raw_writeq definition 2006-06-30 11:25:38 -07:00
ioctl.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ioctls.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ipc.h [PATCH] uml: obvious compile fixes for x86-64 Subarch and x86 regression fixes 2005-05-05 16:36:32 -07:00
ipcbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
irq_vectors.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
irq.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
irqflags.h [PATCH] uml: add asm/irqflags.h 2006-06-05 12:29:17 -07:00
keyboard.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
kmap_types.h [PATCH] uml: make copy_*_user atomic 2006-07-01 09:56:03 -07:00
ldt.h [PATCH] uml: split ldt.h in arch-independent and arch-dependant code 2006-03-31 12:18:51 -08:00
linkage.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
local.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
locks.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mca_dma.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mman.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mmu_context.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
mmu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
module-generic.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
module-i386.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
module-x86_64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
msgbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mtrr.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mutex.h [PATCH] mutex subsystem, add default include/asm-*/mutex.h files 2006-01-09 15:59:19 -08:00
namei.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
page_offset.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
page.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
param.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pci.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pda.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
percpu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pgalloc.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
pgtable-2level.h [PATCH] Standardize pxx_page macros 2006-09-26 08:48:51 -07:00
pgtable-3level.h [PATCH] Standardize pxx_page macros 2006-09-26 08:48:51 -07:00
pgtable.h [PATCH] Standardize pxx_page macros 2006-09-26 08:48:51 -07:00
poll.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
posix_types.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
prctl.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
processor-generic.h [PATCH] uml: thread creation tidying 2006-09-27 08:26:16 -07:00
processor-i386.h [PATCH] uml: implement {get,set}_thread_area for i386 2006-03-31 12:18:52 -08:00
processor-ppc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
processor-x86_64.h [PATCH] uml: implement {get,set}_thread_area for i386 2006-03-31 12:18:52 -08:00
ptrace-generic.h [PATCH] Make UML use ptrace-abi.h 2006-09-26 08:49:10 -07:00
ptrace-i386.h [PATCH] uml: fix "extern-vs-static" proto conflict in TLS code 2006-04-11 06:18:36 -07:00
ptrace-x86_64.h [PATCH] uml: fix missing x86_64 register definitions 2006-09-27 08:26:16 -07:00
resource.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
rwlock.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
rwsem.h [PATCH] remove gcc-2 checks 2006-01-08 20:14:02 -08:00
scatterlist.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sections.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
segment.h [PATCH] uml: check for differences in host support 2006-03-31 12:18:52 -08:00
semaphore.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sembuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
serial.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
setup.h [PATCH] uml: command line handling cleanup 2005-05-06 22:09:29 -07:00
shmbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
shmparam.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigcontext-generic.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigcontext-i386.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigcontext-ppc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigcontext-x86_64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
siginfo.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
signal.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
smp.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
socket.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sockios.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
spinlock_types.h [PATCH] uml spinlock breakage 2005-09-10 16:50:01 -07:00
spinlock.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
stat.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
statfs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
string.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
suspend.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
system-generic.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
system-i386.h [PATCH] uml: UML/i386 cmpxchg fix 2005-09-17 11:50:01 -07:00
system-ppc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
system-x86_64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
termbits.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
termios.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
thread_info.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
timex.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
tlb.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
tlbflush.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
topology.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
types.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
uaccess.h [PATCH] uml: more __user annotations 2006-06-05 12:29:17 -07:00
ucontext.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
unaligned.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
unistd.h [PATCH] uml: use generic sys_rt_sigsuspend 2006-01-18 19:20:30 -08:00
user.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
vga.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
vm86.h [PATCH] uml: vm86 compile fix 2005-07-28 21:46:03 -07:00
vm-flags-i386.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
vm-flags-x86_64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
xor.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00