From 42daba316557e597a90a730f61c762602b7f0e0c Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Tue, 16 Oct 2007 01:26:47 -0700 Subject: uml: stop saving process FP state Throw out a lot of code dealing with saving and restoring floating-point state. In skas mode, where processes run in a restoring floating-point state on kernel entry and exit is pointless. This eliminates most of arch/um/os-Linux/sys-{i386,x86_64}/registers.c. Most of what remained is now arch-indpendent, and can be moved up to arch/um/os-Linux/registers.c. Both arches need the jmp_buf accessor get_thread_reg, and i386 needs {save,restore}_fp_regs because it cheats during sigreturn by getting the fp state using ptrace rather than copying it out of the process sigcontext. After this, it turns out that arch/um/include/skas/mode-skas.h is almost completely unneeded. The declarations in it are variables which either don't exist or which don't have global scope. The one exception is kill_off_processes_skas. If that's removed, this header can be deleted. This uncovered a bug in user.h, which wasn't correctly making sure that a size_t definition was available to both userspace and kernelspace files. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/include/os.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/um/include/os.h') diff --git a/arch/um/include/os.h b/arch/um/include/os.h index bb6b7d9e188..c0803e67fc6 100644 --- a/arch/um/include/os.h +++ b/arch/um/include/os.h @@ -307,6 +307,8 @@ extern int protect(struct mm_id * mm_idp, unsigned long addr, extern int is_skas_winch(int pid, int fd, void *data); extern int start_userspace(unsigned long stub_stack); extern int copy_context_skas0(unsigned long stack, int pid); +extern void save_registers(int pid, union uml_pt_regs *regs); +extern void restore_registers(int pid, union uml_pt_regs *regs); extern void userspace(union uml_pt_regs *regs); extern void map_stub_pages(int fd, unsigned long code, unsigned long data, unsigned long stack); -- cgit v1.2.3-70-g09d2