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 <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/include/user.h b/arch/um/include/user.h
index d380e6d..99033ff 100644
--- a/arch/um/include/user.h
+++ b/arch/um/include/user.h
@@ -14,10 +14,12 @@
*/
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-/*
- * This will provide the size_t definition in both kernel and userspace builds
- */
+/* This is to get size_t */
+#ifdef __KERNEL__
#include <linux/types.h>
+#else
+#include <stddef.h>
+#endif
extern void panic(const char *fmt, ...)
__attribute__ ((format (printf, 1, 2)));