diff options
| author | Jeff Dike <jdike@addtoit.com> | 2005-09-03 15:57:36 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@evo.osdl.org> | 2005-09-05 00:06:22 -0700 |
| commit | c56004901fa5dcf55f92318f192ab3c0e87db2d1 (patch) | |
| tree | ac53ded16ab9886ce05d4b2d424dfed80dce9e57 /arch/um/sys-i386/stub.S | |
| parent | 77fa5adcda6d686d2f45a2b55dcb9a03e7d33fa1 (diff) | |
[PATCH] uml: TLB operation batching
This adds VM op batching to skas0. Rather than having a context switch to and
from the userspace stub for each address space change, we write a number of
operations to the stub data page and invoke a different stub which loops over
them and executes them all in one go.
The operations are stored as [ system call number, arg1, arg2, ... ] tuples.
The set is terminated by a system call number of 0. Single operations, i.e.
page faults, are handled in the old way, since that is slightly more
efficient.
For a kernel build, a minority (~1/4) of the operations are part of a set.
These sets averaged ~100 in length, so for this quarter, the context switching
overhead is greatly reduced.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/um/sys-i386/stub.S')
| -rw-r--r-- | arch/um/sys-i386/stub.S | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/arch/um/sys-i386/stub.S b/arch/um/sys-i386/stub.S index 2f2c70a8f04..a0f9506312d 100644 --- a/arch/um/sys-i386/stub.S +++ b/arch/um/sys-i386/stub.S @@ -6,3 +6,20 @@ syscall_stub: int $0x80 mov %eax, UML_CONFIG_STUB_DATA int3 + + .globl batch_syscall_stub +batch_syscall_stub: + mov $UML_CONFIG_STUB_DATA, %esp +again: pop %eax + cmpl $0, %eax + jz done + pop %ebx + pop %ecx + pop %edx + pop %esi + pop %edi + pop %ebp + int $0x80 + mov %eax, UML_CONFIG_STUB_DATA + jmp again +done: int3 |