Commit ab1b6423 authored by Michael Ellerman's avatar Michael Ellerman Committed by Sasha Levin

powerpc/powernv: Fix opal_exit tracepoint opcode

[ Upstream commit a7e0fb6c ]

Currently the opal_exit tracepoint usually shows the opcode as 0:

  <idle>-0     [047] d.h.   635.654292: opal_entry: opcode=63
  <idle>-0     [047] d.h.   635.654296: opal_exit: opcode=0 retval=0
  kopald-1209  [019] d...   636.420943: opal_entry: opcode=10
  kopald-1209  [019] d...   636.420959: opal_exit: opcode=0 retval=0

This is because we incorrectly load the opcode into r0 before calling
__trace_opal_exit(), whereas it expects the opcode in r3 (first function
parameter). In fact we are leaving the retval in r3, so opcode and
retval will always show the same value.

Instead load the opcode into r3, resulting in:

  <idle>-0     [040] d.h.   636.618625: opal_entry: opcode=63
  <idle>-0     [040] d.h.   636.618627: opal_exit: opcode=63 retval=0

Fixes: c49f6353 ("powernv: Add OPAL tracepoints")
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: default avatarSasha Levin <alexander.levin@verizon.com>
parent 5d1767ce
...@@ -148,7 +148,7 @@ opal_tracepoint_entry: ...@@ -148,7 +148,7 @@ opal_tracepoint_entry:
opal_tracepoint_return: opal_tracepoint_return:
std r3,STK_REG(R31)(r1) std r3,STK_REG(R31)(r1)
mr r4,r3 mr r4,r3
ld r0,STK_REG(R23)(r1) ld r3,STK_REG(R23)(r1)
bl __trace_opal_exit bl __trace_opal_exit
ld r3,STK_REG(R31)(r1) ld r3,STK_REG(R31)(r1)
addi r1,r1,STACKFRAMESIZE addi r1,r1,STACKFRAMESIZE
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment