On Wed, Jun 25, 2014 at 02:55:23PM -0400, Steven Rostedt wrote: > > function_trace_stop is becoming obsolete and archs should no longer be > checking if it is zero or not to perform function tracing. I was able > to figure out how to remove this from all the archs BUT s390, which is > why I'm posting this "Request For Help" email. > > All I want to do is remove any checks to function_trace_stop in the > mcount code. I haven't the foggiest idea on how to change the s390 code > to do this. I made a horrible attempt (attached below) and I now would > like someone to do it right for me :-) > > If you can send me a patch (author it and add your sign off by), I'll > add it to my queue of patches to remove this variable. > > Thanks! Hi Steven, the patch below should do what you want: >From f48d886b7ac0e5eb09c69aafc1f7ba18f6920d5d Mon Sep 17 00:00:00 2001 From: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Date: Thu, 26 Jun 2014 10:43:25 +0200 Subject: [PATCH] s390/ftrace: remove check of obsolete variable function_trace_stop Remove check of obsolete variable function_trace_stop as requested by Steven Rostedt. Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx> --- arch/s390/Kconfig | 1 - arch/s390/kernel/mcount.S | 10 +++------- arch/s390/kernel/mcount64.S | 3 --- 3 files changed, 3 insertions(+), 11 deletions(-) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index bb63499fc5d3..f5af5f6ef0f4 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -116,7 +116,6 @@ config S390 select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER - select HAVE_FUNCTION_TRACE_MCOUNT_TEST select HAVE_FUTEX_CMPXCHG if FUTEX select HAVE_KERNEL_BZIP2 select HAVE_KERNEL_GZIP diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S index 08dcf21cb8df..433c6dbfa442 100644 --- a/arch/s390/kernel/mcount.S +++ b/arch/s390/kernel/mcount.S @@ -21,13 +21,9 @@ ENTRY(_mcount) ENTRY(ftrace_caller) #endif stm %r2,%r5,16(%r15) - bras %r1,2f + bras %r1,1f 0: .long ftrace_trace_function -1: .long function_trace_stop -2: l %r2,1b-0b(%r1) - icm %r2,0xf,0(%r2) - jnz 3f - st %r14,56(%r15) +1: st %r14,56(%r15) lr %r0,%r15 ahi %r15,-96 l %r3,100(%r15) @@ -50,7 +46,7 @@ ENTRY(ftrace_graph_caller) #endif ahi %r15,96 l %r14,56(%r15) -3: lm %r2,%r5,16(%r15) + lm %r2,%r5,16(%r15) br %r14 #ifdef CONFIG_FUNCTION_GRAPH_TRACER diff --git a/arch/s390/kernel/mcount64.S b/arch/s390/kernel/mcount64.S index 1c52eae3396a..c67a8bf0fd9a 100644 --- a/arch/s390/kernel/mcount64.S +++ b/arch/s390/kernel/mcount64.S @@ -20,9 +20,6 @@ ENTRY(_mcount) ENTRY(ftrace_caller) #endif - larl %r1,function_trace_stop - icm %r1,0xf,0(%r1) - bnzr %r14 stmg %r2,%r5,32(%r15) stg %r14,112(%r15) lgr %r1,%r15 -- 1.8.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
