Re: sycall asm inline
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2002-06-19 03:24:00
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2002-06-19 03:24:00
where __syscall_clobbers is just r4-r12. At a later point, some syscalls are instantiated as inline functions: static inline _syscall3(int,read,int,fd,char *,buf,off_t,count) Of course, as long as the syscall reside in a separate function, the ABI guarantees that nothing bad will happen. But when the function is inlined the undeclared side effects could cause problems, or am I missing something?
Probably not missing anything. Now we have to figure the proper set of clobbers, though I'm wondering if we could replace those inline syscalls by direct calls to the proper sys_xxx function. The only advantage I see in doing the syscall from the kernel is that you can "patch" it from a module or whatever, but is this feature used at all ? Ben. ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/