[SPARC64]: Kill all %pstate changes in context switch code.

They are totally unnecessary because:

1) Interrupts are already disabled when switch_to()
   runs.

2) We don't use hard-coded alternate globals any longer.

This found a case in rtrap, which still assumed alternate
global %g6 was current_thread_info(), and that is fixed
by this changeset as well.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 6 deletions

diff --git a/arch/sparc64/kernel/rtrap.S b/arch/sparc64/kernel/rtrap.S
index e6130956307f..a2fa277da62b 100644
--- a/arch/sparc64/kernel/rtrap.S
+++ b/arch/sparc64/kernel/rtrap.S
@@ -224,7 +224,8 @@ rt_continue:	ldx			[%sp + PTREGS_OFF + PT_V9_G1], %g1
                 ldx                     [%sp + PTREGS_OFF + PT_V9_G4], %g4
                 ldx                     [%sp + PTREGS_OFF + PT_V9_G5], %g5
                 brz,pt                  %l3, 1f
-                 nop
+                mov                     %g6, %l2
+
                 /* Must do this before thread reg is clobbered below.  */
                 LOAD_PER_CPU_BASE(%g5, %g6, %i0, %i1, %i2)
 1:
@@ -238,6 +239,8 @@ rt_continue:	ldx			[%sp + PTREGS_OFF + PT_V9_G1], %g1
                 SET_GL(1)
                 .previous
 
+                mov                     %l2, %g6
+
                 ldx                     [%sp + PTREGS_OFF + PT_V9_I0], %i0
                 ldx                     [%sp + PTREGS_OFF + PT_V9_I1], %i1
 
diff --git a/include/asm-sparc64/system.h b/include/asm-sparc64/system.h
index 26c0807af3e4..a18ec87a52c1 100644
--- a/include/asm-sparc64/system.h
+++ b/include/asm-sparc64/system.h
@@ -213,7 +213,6 @@ do {	if (test_thread_flag(TIF_PERFCTR)) {				\
                 task_thread_info(next);                                 \
         __asm__ __volatile__(                                           \
         "mov    %%g4, %%g7\n\t"                                         \
-        "wrpr   %%g0, 0x95, %%pstate\n\t"                               \
         "stx    %%i6, [%%sp + 2047 + 0x70]\n\t"                         \
         "stx    %%i7, [%%sp + 2047 + 0x78]\n\t"                         \
         "rdpr   %%wstate, %%o5\n\t"                                     \
@@ -227,14 +226,10 @@ do {	if (test_thread_flag(TIF_PERFCTR)) {				\
         "ldx    [%%g6 + %3], %%o6\n\t"                                  \
         "ldub   [%%g6 + %2], %%o5\n\t"                                  \
         "ldub   [%%g6 + %4], %%o7\n\t"                                  \
-        "mov    %%g6, %%l2\n\t"                                         \
         "wrpr   %%o5, 0x0, %%wstate\n\t"                                \
         "ldx    [%%sp + 2047 + 0x70], %%i6\n\t"                         \
         "ldx    [%%sp + 2047 + 0x78], %%i7\n\t"                         \
-        "wrpr   %%g0, 0x94, %%pstate\n\t"                               \
-        "mov    %%l2, %%g6\n\t"                                         \
         "ldx    [%%g6 + %6], %%g4\n\t"                                  \
-        "wrpr   %%g0, 0x96, %%pstate\n\t"                               \
         "brz,pt %%o7, 1f\n\t"                                           \
         " mov   %%g7, %0\n\t"                                           \
         "b,a ret_from_syscall\n\t"                                      \