From c56004901fa5dcf55f92318f192ab3c0e87db2d1 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 3 Sep 2005 15:57:36 -0700 Subject: [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 Cc: Paolo Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/include/tlb.h | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-) (limited to 'arch/um/include') diff --git a/arch/um/include/tlb.h b/arch/um/include/tlb.h index c6f9628f39b..2deefb99c63 100644 --- a/arch/um/include/tlb.h +++ b/arch/um/include/tlb.h @@ -9,7 +9,7 @@ #include "um_mmu.h" struct host_vm_op { - enum { MMAP, MUNMAP, MPROTECT } type; + enum { NONE, MMAP, MUNMAP, MPROTECT } type; union { struct { unsigned long addr; @@ -38,24 +38,10 @@ extern void mprotect_kernel_vm(int w); extern void force_flush_all(void); extern void fix_range_common(struct mm_struct *mm, unsigned long start_addr, unsigned long end_addr, int force, - void (*do_ops)(union mm_context *, - struct host_vm_op *, int)); + void *(*do_ops)(union mm_context *, + struct host_vm_op *, int, int, + void *)); extern int flush_tlb_kernel_range_common(unsigned long start, unsigned long end); -extern int add_mmap(unsigned long virt, unsigned long phys, unsigned long len, - int r, int w, int x, struct host_vm_op *ops, int index, - int last_filled, union mm_context *mmu, - void (*do_ops)(union mm_context *, struct host_vm_op *, - int)); -extern int add_munmap(unsigned long addr, unsigned long len, - struct host_vm_op *ops, int index, int last_filled, - union mm_context *mmu, - void (*do_ops)(union mm_context *, struct host_vm_op *, - int)); -extern int add_mprotect(unsigned long addr, unsigned long len, int r, int w, - int x, struct host_vm_op *ops, int index, - int last_filled, union mm_context *mmu, - void (*do_ops)(union mm_context *, struct host_vm_op *, - int)); #endif -- cgit v1.2.3