diff mbox

[v8,1/3] perf annotate: Show raw form for jump instruction with indirect target

Message ID 1480953407-7605-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
State New
Headers show

Commit Message

Ravi Bangoria Dec. 5, 2016, 3:56 p.m. UTC
For jump instructions that does not include target address as direct
operand, show the original disassembled line for them. This is needed
for certain powerpc jump instructions that use target address in a
register (such as bctr, btar, ...).

Before:
     ld     r12,32088(r12)
     mtctr  r12
  v  bctr   ffffffffffffca2c
     std    r2,24(r1)
     addis  r12,r2,-1

After:
     ld     r12,32088(r12)
     mtctr  r12
  v  bctr
     std    r2,24(r1)
     addis  r12,r2,-1

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
---
Changes in v8:
  - v7: https://lkml.org/lkml/2016/9/21/436
  - Rebase to acme/perf/core
  - No logical changes. (Cross arch annotate patches are in. This patch
    is for hardening annotate for powerpc.)

 tools/perf/util/annotate.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Arnaldo Carvalho de Melo Dec. 5, 2016, 7:22 p.m. UTC | #1
Em Mon, Dec 05, 2016 at 09:26:45PM +0530, Ravi Bangoria escreveu:
> For jump instructions that does not include target address as direct
> operand, show the original disassembled line for them. This is needed
> for certain powerpc jump instructions that use target address in a
> register (such as bctr, btar, ...).

Please, mention the name of the function where you copy annotated
examples from, so that I can reproduce it here, using the files you
provided (perf.data and vmlinux for powerpc).

Searching one such function now...
 
> Before:
>      ld     r12,32088(r12)
>      mtctr  r12
>   v  bctr   ffffffffffffca2c
>      std    r2,24(r1)
>      addis  r12,r2,-1
> 
> After:
>      ld     r12,32088(r12)
>      mtctr  r12
>   v  bctr
>      std    r2,24(r1)
>      addis  r12,r2,-1
> 
> Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> ---
> Changes in v8:
>   - v7: https://lkml.org/lkml/2016/9/21/436
>   - Rebase to acme/perf/core
>   - No logical changes. (Cross arch annotate patches are in. This patch
>     is for hardening annotate for powerpc.)
> 
>  tools/perf/util/annotate.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 4012b1d..ea7e0de 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -237,6 +237,9 @@ static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *op
>  static int jump__scnprintf(struct ins *ins, char *bf, size_t size,
>  			   struct ins_operands *ops)
>  {
> +	if (!ops->target.addr)
> +		return ins__raw_scnprintf(ins, bf, size, ops);
> +
>  	return scnprintf(bf, size, "%-6.6s %" PRIx64, ins->name, ops->target.offset);
>  }
>  
> -- 
> 2.4.11
Arnaldo Carvalho de Melo Dec. 5, 2016, 8:21 p.m. UTC | #2
Em Mon, Dec 05, 2016 at 09:26:45PM +0530, Ravi Bangoria escreveu:
> For jump instructions that does not include target address as direct
> operand, show the original disassembled line for them. This is needed
> for certain powerpc jump instructions that use target address in a
> register (such as bctr, btar, ...).

Found it, .__bpf_prog_run, that is present in that perf.data file you
sent me, has it, will use it in my committer notes for this patch.

- Arnaldo

> 
> Before:
>      ld     r12,32088(r12)
>      mtctr  r12
>   v  bctr   ffffffffffffca2c
>      std    r2,24(r1)
>      addis  r12,r2,-1
> 
> After:
>      ld     r12,32088(r12)
>      mtctr  r12
>   v  bctr
>      std    r2,24(r1)
>      addis  r12,r2,-1
> 
> Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> ---
> Changes in v8:
>   - v7: https://lkml.org/lkml/2016/9/21/436
>   - Rebase to acme/perf/core
>   - No logical changes. (Cross arch annotate patches are in. This patch
>     is for hardening annotate for powerpc.)
> 
>  tools/perf/util/annotate.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 4012b1d..ea7e0de 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -237,6 +237,9 @@ static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *op
>  static int jump__scnprintf(struct ins *ins, char *bf, size_t size,
>  			   struct ins_operands *ops)
>  {
> +	if (!ops->target.addr)
> +		return ins__raw_scnprintf(ins, bf, size, ops);
> +
>  	return scnprintf(bf, size, "%-6.6s %" PRIx64, ins->name, ops->target.offset);
>  }
>  
> -- 
> 2.4.11
Arnaldo Carvalho de Melo Dec. 5, 2016, 8:31 p.m. UTC | #3
Em Mon, Dec 05, 2016 at 05:21:42PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Dec 05, 2016 at 09:26:45PM +0530, Ravi Bangoria escreveu:
> > For jump instructions that does not include target address as direct
> > operand, show the original disassembled line for them. This is needed
> > for certain powerpc jump instructions that use target address in a
> > register (such as bctr, btar, ...).
> 
> Found it, .__bpf_prog_run, that is present in that perf.data file you
> sent me, has it, will use it in my committer notes for this patch.

So, I've added these committer notes while testing it, will continue
processing your patches later/tomorrow, thanks!

    Committer notes:
    
    Testing it using a perf.data file and vmlinux for powerpc64,
    cross-annotating it on a x86_64 workstation:
    
    Before:
    
      .__bpf_prog_run  vmlinux.powerpc
             │        std    r10,512(r9)                      ▒
             │        lbz    r9,0(r31)                        ▒
             │        rldicr r9,r9,3,60                       ▒
             │        ldx    r9,r30,r9                        ▒
             │        mtctr  r9                               ▒
      100.00 │      ↓ bctr   3fffffffffe01510                 ▒
             │        lwa    r10,4(r31)                       ▒
             │        lwz    r9,0(r31)                        ▒
      <SNIP>
      Invalid jump offset: 3fffffffffe01510
    
    After:
    
      .__bpf_prog_run  vmlinux.powerpc
             │        std    r10,512(r9)                      ▒
             │        lbz    r9,0(r31)                        ▒
             │        rldicr r9,r9,3,60                       ▒
             │        ldx    r9,r30,r9                        ▒
             │        mtctr  r9                               ▒
      100.00 │      ↓ bctr                                    ▒
             │        lwa    r10,4(r31)                       ▒
             │        lwz    r9,0(r31)                        ▒
      <SNIP>
      Invalid jump offset: 3fffffffffe01510
    
    This, in turn, uncovers another problem with jumps without operands, the
    ENTER/-> operation, to jump to the target, still continues using the bogus
    target :-)
    
    BTW, this was the file used for the above tests:
    
      [acme@jouet ravi_bangoria]$ perf report --header-only -i perf.data.f22vm.powerdev
      # ========
      # captured on: Thu Nov 24 12:40:38 2016
      # hostname : pdev-f22-qemu
      # os release : 4.4.10-200.fc22.ppc64
      # perf version : 4.9.rc1.g6298ce
      # arch : ppc64
      # nrcpus online : 48
      # nrcpus avail : 48
      # cpudesc : POWER7 (architected), altivec supported
      # cpuid : 74,513
      # total memory : 4158976 kB
      # cmdline : /home/ravi/Workspace/linux/tools/perf/perf record -a
      # event : name = cycles:ppp, , size = 112, { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|CPU|PERIOD, disabled = 1, inherit = 1, mmap = 1, c
      # HEADER_CPU_TOPOLOGY info available, use -I to display
      # HEADER_NUMA_TOPOLOGY info available, use -I to display
      # pmu mappings: cpu = 4, software = 1, tracepoint = 2, breakpoint = 5
      # missing features: HEADER_TRACING_DATA HEADER_BRANCH_STACK HEADER_GROUP_DESC HEADER_AUXTRACE HEADER_STAT HEADER_CACHE
      # ========
      #
      [acme@jouet ravi_bangoria]$
    
    Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
    Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
    Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 
> - Arnaldo
> 
> > 
> > Before:
> >      ld     r12,32088(r12)
> >      mtctr  r12
> >   v  bctr   ffffffffffffca2c
> >      std    r2,24(r1)
> >      addis  r12,r2,-1
> > 
> > After:
> >      ld     r12,32088(r12)
> >      mtctr  r12
> >   v  bctr
> >      std    r2,24(r1)
> >      addis  r12,r2,-1
> > 
> > Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
> > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> > ---
> > Changes in v8:
> >   - v7: https://lkml.org/lkml/2016/9/21/436
> >   - Rebase to acme/perf/core
> >   - No logical changes. (Cross arch annotate patches are in. This patch
> >     is for hardening annotate for powerpc.)
> > 
> >  tools/perf/util/annotate.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> > index 4012b1d..ea7e0de 100644
> > --- a/tools/perf/util/annotate.c
> > +++ b/tools/perf/util/annotate.c
> > @@ -237,6 +237,9 @@ static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *op
> >  static int jump__scnprintf(struct ins *ins, char *bf, size_t size,
> >  			   struct ins_operands *ops)
> >  {
> > +	if (!ops->target.addr)
> > +		return ins__raw_scnprintf(ins, bf, size, ops);
> > +
> >  	return scnprintf(bf, size, "%-6.6s %" PRIx64, ins->name, ops->target.offset);
> >  }
> >  
> > -- 
> > 2.4.11
Ravi Bangoria Dec. 13, 2016, 4:15 p.m. UTC | #4
Hi Arnaldo,

Can you please review 2nd and 3rd patch.

-Ravi

On Monday 05 December 2016 09:26 PM, Ravi Bangoria wrote:
> For jump instructions that does not include target address as direct
> operand, show the original disassembled line for them. This is needed
> for certain powerpc jump instructions that use target address in a
> register (such as bctr, btar, ...).
>
> Before:
>      ld     r12,32088(r12)
>      mtctr  r12
>   v  bctr   ffffffffffffca2c
>      std    r2,24(r1)
>      addis  r12,r2,-1
>
> After:
>      ld     r12,32088(r12)
>      mtctr  r12
>   v  bctr
>      std    r2,24(r1)
>      addis  r12,r2,-1
>
> Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> ---
> Changes in v8:
>   - v7: https://lkml.org/lkml/2016/9/21/436
>   - Rebase to acme/perf/core
>   - No logical changes. (Cross arch annotate patches are in. This patch
>     is for hardening annotate for powerpc.)
>
>  tools/perf/util/annotate.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 4012b1d..ea7e0de 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -237,6 +237,9 @@ static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *op
>  static int jump__scnprintf(struct ins *ins, char *bf, size_t size,
>  			   struct ins_operands *ops)
>  {
> +	if (!ops->target.addr)
> +		return ins__raw_scnprintf(ins, bf, size, ops);
> +
>  	return scnprintf(bf, size, "%-6.6s %" PRIx64, ins->name, ops->target.offset);
>  }
>
diff mbox

Patch

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 4012b1d..ea7e0de 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -237,6 +237,9 @@  static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *op
 static int jump__scnprintf(struct ins *ins, char *bf, size_t size,
 			   struct ins_operands *ops)
 {
+	if (!ops->target.addr)
+		return ins__raw_scnprintf(ins, bf, size, ops);
+
 	return scnprintf(bf, size, "%-6.6s %" PRIx64, ins->name, ops->target.offset);
 }