[PATCH] Add some comments to entry.S

 * - partial stack frame: partially saved registers upto R11.

 * - full stack frame: Like partial stack frame, but all register saved. 

 *

 * TODO:	 

 * - schedule it carefully for the final hardware.

 * Some macro usage:

 * - CFI macros are used to generate dwarf2 unwind information for better

 * backtraces. They don't change any code.

 * - SAVE_ALL/RESTORE_ALL - Save/restore all registers

 * - SAVE_ARGS/RESTORE_ARGS - Save/restore registers that C functions modify.

 * There are unfortunately lots of special cases where some registers

 * not touched. The macro is a big mess that should be cleaned up.

 * - SAVE_REST/RESTORE_REST - Handle the registers not saved by SAVE_ARGS.

 * Gives a full stack frame.

 * - ENTRY/END Define functions in the symbol table.

 * - FIXUP_TOP_OF_STACK/RESTORE_TOP_OF_STACK - Fix up the hardware stack

 * frame that is otherwise undefined after a SYSCALL

 * - TRACE_IRQ_* - Trace hard interrupt state for lock debugging.

 * - errorentry/paranoidentry/zeroentry - Define exception entry points.

 */

#include <linux/linkage.h>