arch/tile: eliminate pt_regs trampolines for syscalls

Using the new current_pt_regs() model, we can remove some trampolines
from assembly code and call directly to the C syscall implementations.
rt_sigreturn() and clone() still need some assembly wrapping, but no
longer are passed a pt_regs pointer.  sigaltstack() and the
tilepro-specific cmpxchg_badaddr() syscalls are now just straight C.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/tile/mm/fault.c b/arch/tile/mm/fault.c
index fe811fa5f1b9..3d2b81c163a6 100644
--- a/arch/tile/mm/fault.c
+++ b/arch/tile/mm/fault.c
@@ -70,9 +70,10 @@ static noinline void force_sig_info_fault(const char *type, int si_signo,
  * Synthesize the fault a PL0 process would get by doing a word-load of
  * an unaligned address or a high kernel address.
  */
-SYSCALL_DEFINE2(cmpxchg_badaddr, unsigned long, address,
-                struct pt_regs *, regs)
+SYSCALL_DEFINE1(cmpxchg_badaddr, unsigned long, address)
 {
+        struct pt_regs *regs = current_pt_regs();
+
         if (address >= PAGE_OFFSET)
                 force_sig_info_fault("atomic segfault", SIGSEGV, SEGV_MAPERR,
                                      address, INT_DTLB_MISS, current, regs);