tmp_suning_uos_patched/arch/um/include
Jeff Dike 1d7173baf2 [PATCH] uml: implement soft interrupts
This patch implements soft interrupts.  Interrupt enabling and disabling no
longer map to sigprocmask.  Rather, a flag is set indicating whether
interrupts may be handled.  If a signal comes in and interrupts are marked as
OK, then it is handled normally.  If interrupts are marked as off, then the
signal handler simply returns after noting that a signal needs handling.  When
interrupts are enabled later on, this pending signals flag is checked, and the
IRQ handlers are called at that point.

The point of this is to reduce the cost of local_irq_save et al, since they
are very much more common than the signals that they are enabling and
disabling.  Soft interrupts produce a speed-up of ~25% on a kernel build.

Subtleties -

    UML uses sigsetjmp/siglongjmp to switch contexts.  sigsetjmp has been
    wrapped in a save_flags-like macro which remembers the interrupt state at
    setjmp time, and restores it when it is longjmp-ed back to.

    The enable_signals function has to loop because the IRQ handler
    disables interrupts before returning.  enable_signals has to return with
    signals enabled, and signals may come in between the disabling and the
    return to enable_signals.  So, it loops for as long as there are pending
    signals, ensuring that signals are enabled when it finally returns, and
    that there are no pending signals that need to be dealt with.

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>
2006-01-18 19:20:20 -08:00
..
skas [PATCH] uml: move libc-dependent skas process handling 2006-01-18 19:20:19 -08:00
sysdep-i386 return statement cleanup - kill pointless parentheses 2006-01-15 02:37:08 +01:00
sysdep-ia64 [PATCH] uml: S390 preparation, abstract host page fault data 2005-05-05 16:36:36 -07:00
sysdep-ppc [PATCH] uml: S390 preparation, abstract host page fault data 2005-05-05 16:36:36 -07:00
sysdep-x86_64 [PATCH] uml: fix missing KBUILD_BASENAME 2006-01-11 18:42:09 -08:00
tt [PATCH] uml: move headers to arch/um/include 2006-01-18 19:20:19 -08:00
aio.h [PATCH] uml: revert block driver use of host AIO 2005-10-12 08:22:26 -07:00
chan_kern.h [PATCH] uml: Add throttling to console driver 2006-01-06 08:33:46 -08:00
chan_user.h [PATCH] uml console channels: fix the API of console_write 2005-11-13 18:14:14 -08:00
choose-mode.h [PATCH] uml: better diagnostics for broken configs 2006-01-06 08:33:47 -08:00
common-offsets.h [PATCH] uml makefiles sanitized 2005-09-29 08:46:26 -07:00
elf_user.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
frame_kern.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
init.h [PATCH] uml: use host AIO support 2005-09-05 00:06:23 -07:00
initrd.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
irq_kern.h [PATCH] uml: use host AIO support 2005-09-05 00:06:23 -07:00
irq_user.h [PATCH] uml: Simplify console opening/closing and irq registration 2006-01-06 08:33:46 -08:00
kern_util.h [PATCH] uml: move libc-dependent code from trap_user.c 2006-01-08 20:13:39 -08:00
kern.h [PATCH] uml: separate libc-dependent umid code 2006-01-06 08:33:47 -08:00
line.h [PATCH] uml: Add throttling to console driver 2006-01-06 08:33:46 -08:00
longjmp.h [PATCH] uml: implement soft interrupts 2006-01-18 19:20:20 -08:00
mconsole_kern.h [PATCH] uml: hot-unplug code cleanup 2005-06-25 16:24:36 -07:00
mconsole.h [PATCH] uml: add mconsole_reply variant with length param 2006-01-06 08:33:47 -08:00
mem_kern.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mem_user.h [PATCH] uml: big memory fixes 2005-11-07 07:53:31 -08:00
mem.h [PATCH] uml: inline mk_pte and various friends 2005-09-10 12:00:18 -07:00
mode_kern.h [PATCH] uml: move headers to arch/um/include 2006-01-18 19:20:19 -08:00
mode.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
net_kern.h [PATCH] missing platform_device.h includes 2005-11-01 21:50:01 -08:00
net_user.h [PATCH] uml: fix UML network driver endianness bugs 2005-11-07 07:53:30 -08:00
os.h [PATCH] uml: move libc-dependent skas process handling 2006-01-18 19:20:19 -08:00
process.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ptrace_user.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
registers.h [PATCH] uml: Fix sysrq-r support for skas mode 2005-10-04 13:22:01 -07:00
sigcontext.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigio.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
signal_kern.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
skas_ptrace.h [PATCH] uml: header and code cleanup 2005-05-05 16:36:39 -07:00
skas_ptregs.h [PATCH] uml makefiles sanitized 2005-09-29 08:46:26 -07:00
syscall.h [PATCH] uml: system call path cleanup 2005-09-05 00:06:23 -07:00
sysrq.h [PATCH] uml: stack dump fix 2005-05-28 16:46:13 -07:00
task.h [PATCH] uml makefiles sanitized 2005-09-29 08:46:26 -07:00
tempfile.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
tlb.h [PATCH] mm: uml kill unused 2005-10-29 21:40:42 -07:00
ubd_user.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
um_mmu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
um_uaccess.h [PATCH] uml: fix compile error for tt 2005-12-12 08:57:43 -08:00
umid.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
uml_uaccess.h [PATCH] uml: separate libc-dependent uaccess code 2005-11-07 07:53:31 -08:00
user_util.h [PATCH] uml: move libc-dependent utility procedures 2006-01-18 19:20:19 -08:00
user.h [PATCH] strlcat: use for uml umid.c 2005-09-22 22:17:36 -07:00