From 6e02493a7f33ac89e698b980a657d77ab2749eaf Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sun, 5 Feb 2006 20:47:26 -0800 Subject: [PATCH] [SPARC64]: Fill dead cycles on trap entry with real work. As we save trap state onto the stack, the store buffer fills up mid-way through and we stall for several cycles as the store buffer trickles out to the L2 cache. Meanwhile we can do some privileged register reads and other calculations, essentially for free. Signed-off-by: David S. Miller --- arch/sparc64/kernel/etrap.S | 27 +++++++++++++++------------ 1 file changed, 15 insertions(+), 12 deletions(-) diff --git a/arch/sparc64/kernel/etrap.S b/arch/sparc64/kernel/etrap.S index 4a0e01b14044..f2556146a735 100644 --- a/arch/sparc64/kernel/etrap.S +++ b/arch/sparc64/kernel/etrap.S @@ -98,37 +98,40 @@ etrap_save: save %g2, -STACK_BIAS, %sp stxa %g3, [%l4] ASI_DMMU sethi %hi(KERNBASE), %l4 flush %l4 - wr %g0, ASI_AIUS, %asi -2: wrpr %g0, 0x0, %tl - mov %g4, %l4 + mov ASI_AIUS, %l7 +2: mov %g4, %l4 mov %g5, %l5 - - mov %g7, %l2 + add %g7, 4, %l2 wrpr %g0, ETRAP_PSTATE1, %pstate stx %g1, [%sp + PTREGS_OFF + PT_V9_G1] stx %g2, [%sp + PTREGS_OFF + PT_V9_G2] + sllx %l7, 24, %l7 stx %g3, [%sp + PTREGS_OFF + PT_V9_G3] + rdpr %cwp, %l0 stx %g4, [%sp + PTREGS_OFF + PT_V9_G4] stx %g5, [%sp + PTREGS_OFF + PT_V9_G5] stx %g6, [%sp + PTREGS_OFF + PT_V9_G6] - stx %g7, [%sp + PTREGS_OFF + PT_V9_G7] + or %l7, %l0, %l7 + sethi %hi(TSTATE_RMO | TSTATE_PEF), %l0 + or %l7, %l0, %l7 + wrpr %l2, %tnpc + wrpr %l7, (TSTATE_PRIV | TSTATE_IE), %tstate stx %i0, [%sp + PTREGS_OFF + PT_V9_I0] stx %i1, [%sp + PTREGS_OFF + PT_V9_I1] stx %i2, [%sp + PTREGS_OFF + PT_V9_I2] stx %i3, [%sp + PTREGS_OFF + PT_V9_I3] stx %i4, [%sp + PTREGS_OFF + PT_V9_I4] stx %i5, [%sp + PTREGS_OFF + PT_V9_I5] - stx %i6, [%sp + PTREGS_OFF + PT_V9_I6] - stx %i7, [%sp + PTREGS_OFF + PT_V9_I7] - wrpr %g0, ETRAP_PSTATE2, %pstate mov %l6, %g6 + stx %i7, [%sp + PTREGS_OFF + PT_V9_I7] LOAD_PER_CPU_BASE(%g5, %g6, %g4, %g3, %l1) - jmpl %l2 + 0x4, %g0 - ldx [%g6 + TI_TASK], %g4 + ldx [%g6 + TI_TASK], %g4 + done -3: ldub [%l6 + TI_FPDEPTH], %l5 +3: mov ASI_P, %l7 + ldub [%l6 + TI_FPDEPTH], %l5 add %l6, TI_FPSAVED + 1, %l4 srl %l5, 1, %l3 add %l5, 2, %l5 -- 2.30.2