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New attempt at adding an disassembler to perf

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  New attempt at adding an disassembler to perf Andi Kleen <andi@firstfloor.org> - 2017-01-03 10:10 +0100
    [PATCH 4/4] perf, tools, script: Add brstackasm output for branch stacks Andi Kleen <andi@firstfloor.org> - 2017-01-03 10:10 +0100
      Re: [PATCH 4/4] perf, tools, script: Add brstackasm output for  branch stacks Jiri Olsa <jolsa@redhat.com> - 2017-01-08 15:30 +0100
        Re: [PATCH 4/4] perf, tools, script: Add brstackasm output for  branch stacks Andi Kleen <ak@linux.intel.com> - 2017-01-09 20:20 +0100
      Re: [PATCH 4/4] perf, tools, script: Add brstackasm output for  branch stacks Jiri Olsa <jolsa@redhat.com> - 2017-01-08 15:30 +0100
    [PATCH 3/4] perf, tools, script: Add support for printing assembler Andi Kleen <andi@firstfloor.org> - 2017-01-03 10:10 +0100
    Re: New attempt at adding an disassembler to perf Jiri Olsa <jolsa@redhat.com> - 2017-01-08 15:30 +0100

#1549626 — New attempt at adding an disassembler to perf

A native disassembler in perf is very useful, in particular with perf script to trace 
instruction streams, but also for other analysis. Previously I attempted
to do this using the udis86 library, but that was rejected because:
- udis86 was not maintained anymore and lacking recent instructions
- udis86 is dynamically linked and gives a runtime dependency.
Doing this needs a full disassembler, not just a decoder, so the existing
instruction decoder cannot be used without major changes.

This patchkit addresses these issues.  Intel recently released an open source version
of the XED disassembler library, which is used in many other Intel software.
It is very well maintained, uptodate, and supports static linking, so there is no
runtime dependency. This version adds XED support to perf, and uses it to implement
assembler output in perf script. It also fixes a range of issues in the previous
version, see the individual change logs.

Available in 
git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-misc.git perf/xed-3

v1: First post of XED version

-Andi

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#1549627 — [PATCH 4/4] perf, tools, script: Add brstackasm output for branch stacks

From: Andi Kleen <ak@linux.intel.com>

Implement printing full disassembled sequences for branch stacks in perf
script. This allows to directly print hot paths for individual samples,
together with branch misprediction and cycle count / IPC information if
available (on Skylake systems)

% perf record -b ...
% perf script -F brstackasm
...
        000055b55d1147d0        pushq  %rbp
        000055b55d1147d1        pushq  %r15
        000055b55d1147d3        pushq  %r14
        000055b55d1147d5        pushq  %r13
        000055b55d1147d7        pushq  %r12
        000055b55d1147d9        pushq  %rbx
        000055b55d1147da        sub $0x18, %rsp
        000055b55d1147de        mov %r8, %r13
        000055b55d1147e1        mov %rcx, %rbp
        000055b55d1147e4        mov %rdx, %r14
        000055b55d1147e7        mov %rsi, %r15
        000055b55d1147ea        mov %rdi, %rbx
        000055b55d1147ed        movl  $0x0, 0xc(%rsp)
        000055b55d1147f5        movq  (%rbp), %rax
        000055b55d1147f9        test $0x1, %al
        000055b55d1147fb        jnz 0x55b55d114890              # PRED 4 cycles 3.75 IPC
        000055b55d114890        mov %eax, %ecx
        000055b55d114892        and $0x3, %ecx
        000055b55d114895        cmp $0x1, %rcx
        000055b55d114899        jnz 0x55b55d1148f8
        000055b55d11489b        movq  -0x1(%rax), %rcx
        000055b55d11489f        cmpb  $0x81, 0xb(%rcx)
        000055b55d1148a3        jnz 0x55b55d1148fe              # PRED 1 cycles 6.00 IPC
...

Open issues:
- Occasionally the path does not reach up to the sample IP, as the LBRs
may be freezed earlier.

v2:
Use low level abstracted disassembler interface.
Print symbols and source lines as labels.
Print first jump in LBR too.
Patch up blocks with filtered ring transfers.
Show IPC
Lots of cleanups and improvements.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 tools/perf/Documentation/perf-script.txt |  13 +-
 tools/perf/builtin-script.c              | 262 +++++++++++++++++++++++++++++++
 2 files changed, 273 insertions(+), 2 deletions(-)

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index 863579b4d2e2..9b3c0e58f315 100644
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -116,7 +116,7 @@ OPTIONS
 --fields::
         Comma separated list of fields to print. Options are:
         comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff,
-        srcline, period, iregs, brstack, brstacksym, flags, bpf-output, asm.
+	srcline, period, iregs, brstack, brstacksym, flags, bpf-output, asm, brstackasm,
         callindent, insn, insnlen. Field list can be prepended with the type, trace, sw or hw,
         to indicate to which event type the field list applies.
         e.g., -F sw:comm,tid,time,ip,sym  and -F trace:time,cpu,trace
@@ -189,17 +189,22 @@ OPTIONS
 	i.e., -F "" is not allowed.
 
 	The brstack output includes branch related information with raw addresses using the
-	/v/v/v/v/ syntax in the following order:
+	/v/v/v/v/cycles syntax in the following order:
 	FROM: branch source instruction
 	TO  : branch target instruction
         M/P/-: M=branch target mispredicted or branch direction was mispredicted, P=target predicted or direction predicted, -=not supported
 	X/- : X=branch inside a transactional region, -=not in transaction region or not supported
 	A/- : A=TSX abort entry, -=not aborted region or not supported
+	cycles
 
 	The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.
 
 	When asm is specified the assembler instruction of each sample is printed in disassembled form.
 
+	When brstackasm is specified the full assembler sequences of branch sequences for each sample
+	is printed. This is the full execution path leading to the sample. This is only supported when the
+	sample was recorded with perf record -b or -j any.
+
 -k::
 --vmlinux=<file>::
         vmlinux pathname
@@ -301,6 +306,10 @@ include::itrace.txt[]
 	stop time is not given (i.e, time string is 'x.y,') then analysis goes
 	to end of file.
 
+--max-blocks::
+	Set the maximum number of program blocks to print with brstackasm for
+	each sample.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-script-perl[1],
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index e96668b1cc63..b19e207528d2 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -43,6 +43,7 @@ static bool			nanosecs;
 static const char		*cpu_list;
 static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
 static struct perf_stat_config	stat_config;
+static int			max_blocks;
 
 unsigned int scripting_max_stack = PERF_MAX_STACK_DEPTH;
 
@@ -71,6 +72,7 @@ enum perf_output_field {
 	PERF_OUTPUT_INSN	    = 1U << 21,
 	PERF_OUTPUT_INSNLEN	    = 1U << 22,
 	PERF_OUTPUT_ASM		    = 1U << 23,
+	PERF_OUTPUT_BRSTACKASM	    = 1U << 24,
 };
 
 struct output_option {
@@ -101,6 +103,7 @@ struct output_option {
 	{.str = "insn", .field = PERF_OUTPUT_INSN},
 	{.str = "insnlen", .field = PERF_OUTPUT_INSNLEN},
 	{.str = "asm", .field = PERF_OUTPUT_ASM},
+	{.str = "brstackasm", .field = PERF_OUTPUT_BRSTACKASM},
 };
 
 /* default set to maintain compatibility with current format */
@@ -300,6 +303,13 @@ static int perf_evsel__check_attr(struct perf_evsel *evsel,
 		       "selected.\n");
 		return -EINVAL;
 	}
+	if (PRINT_FIELD(BRSTACKASM) &&
+	    !(perf_evlist__combined_branch_type(session->evlist) &
+	      PERF_SAMPLE_BRANCH_ANY)) {
+		pr_err("Display of branch stack assembler requested, but non all-branch filter set\n");
+		return -EINVAL;
+	}
+
 	if ((PRINT_FIELD(PID) || PRINT_FIELD(TID)) &&
 		perf_evsel__check_stype(evsel, PERF_SAMPLE_TID, "TID",
 					PERF_OUTPUT_TID|PERF_OUTPUT_PID))
@@ -586,6 +596,254 @@ static void print_sample_brstacksym(struct perf_sample *sample,
 	}
 }
 
+#define MAXBB 16384UL
+
+static int grab_bb(u8 *buffer, u64 start, u64 end,
+		    struct machine *machine, struct thread *thread,
+		    bool *is64bit, u8 *cpumode)
+{
+	int offset, len;
+	struct addr_location al;
+	bool kernel;
+
+	if (!start || !end)
+		return 0;
+
+	kernel = machine__kernel_ip(machine, start);
+	if (kernel)
+		*cpumode = PERF_RECORD_MISC_KERNEL;
+	else
+		*cpumode = PERF_RECORD_MISC_USER;
+
+	/*
+	 * Block overlaps between kernel and user.
+	 * This can happen due to ring filtering
+	 * On Intel CPUs the entry into the kernel is filtered,
+	 * but the exit is not. Let the caller patch it up.
+	 */
+	if (kernel != machine__kernel_ip(machine, end)) {
+		printf("\tblock %" PRIx64 "-%" PRIx64 " transfers between kernel and user\n",
+				start, end);
+		return -ENXIO;
+	}
+
+	memset(&al, 0, sizeof(al));
+	if (end - start > MAXBB - MAXINSN) {
+		printf("\tblock %" PRIx64 "-%" PRIx64 " (%ld) too long to dump\n",
+		       start, end, end - start);
+		return 0;
+	}
+
+	thread__find_addr_map(thread, *cpumode, MAP__FUNCTION, start, &al);
+	if (!al.map || !al.map->dso) {
+		printf("\tcannot resolve %" PRIx64 "-%" PRIx64 "\n",
+				start, end);
+		return 0;
+	}
+	if (al.map->dso->data.status == DSO_DATA_STATUS_ERROR) {
+		printf("\tcannot resolve %" PRIx64 "-%" PRIx64 "\n",
+				start, end);
+		return 0;
+	}
+
+	/* Load maps to ensure dso->is_64_bit has been updated */
+	map__load(al.map);
+
+	offset = al.map->map_ip(al.map, start);
+	len = dso__data_read_offset(al.map->dso, machine,
+				    offset, (u8 *)buffer,
+				    end - start + MAXINSN);
+
+	*is64bit = al.map->dso->is_64_bit;
+	if (len <= 0)
+		printf("\tcannot fetch code for block at %" PRIx64 "-%" PRIx64 "\n",
+			start, end);
+	return len;
+}
+
+static void print_jump(uint64_t ip, struct branch_entry *en,
+		       struct perf_dis *x, u8 *inbuf, int len,
+		       int insn)
+{
+	printf("\t%016" PRIx64 "\t%-30s\t#%s%s%s%s",
+	       ip,
+	       disas_inst(x, ip, inbuf, len, NULL),
+	       en->flags.predicted ? " PRED" : "",
+	       en->flags.mispred ? " MISPRED" : "",
+	       en->flags.in_tx ? " INTX" : "",
+	       en->flags.abort ? " ABORT" : "");
+	if (en->flags.cycles) {
+		printf(" %d cycles", en->flags.cycles);
+		if (insn)
+			printf(" %.2f IPC", (float)insn / en->flags.cycles);
+	}
+	putchar('\n');
+}
+
+static void print_ip_sym(struct thread *thread,
+			 u8 cpumode, int cpu,
+			 uint64_t addr,
+			 struct symbol **lastsym,
+			 struct perf_event_attr *attr)
+{
+	struct addr_location al;
+	int off;
+
+	memset(&al, 0, sizeof(struct addr_location));
+
+	thread__find_addr_map(thread, cpumode, MAP__FUNCTION, addr, &al);
+	if (!al.map)
+		thread__find_addr_map(thread, cpumode, MAP__VARIABLE,
+				      addr, &al);
+	if ((*lastsym) && al.addr >= (*lastsym)->start && al.addr < (*lastsym)->end)
+		return;
+
+	al.cpu = cpu;
+	al.sym = NULL;
+	if (al.map)
+		al.sym = map__find_symbol(al.map, al.addr);
+
+	if (!al.sym)
+		return;
+
+	if (al.addr < al.sym->end)
+		off = al.addr - al.sym->start;
+	else
+		off = al.addr - al.map->start - al.sym->start;
+	printf("\t%s", al.sym->name);
+	if (off)
+		printf("%+d", off);
+	putchar(':');
+	if (PRINT_FIELD(SRCLINE))
+		map__fprintf_srcline(al.map, al.addr, "\t", stdout);
+	putchar('\n');
+	*lastsym = al.sym;
+}
+
+static void print_sample_brstackasm(struct perf_sample *sample,
+				    struct thread *thread,
+				    struct perf_event_attr *attr,
+				    struct machine *machine)
+{
+	struct branch_stack *br = sample->branch_stack;
+	u64 start, end;
+	int i, insn;
+	struct perf_dis x;
+	u8 buffer[MAXBB];
+	int len;
+	int nr;
+	unsigned off;
+	int ilen;
+	struct symbol *lastsym = NULL;
+
+	if (!(br && br->nr))
+		return;
+	nr = br->nr;
+	if (max_blocks && nr > max_blocks + 1)
+		nr = max_blocks + 1;
+
+	x.thread = thread;
+	x.cpu = sample->cpu;
+
+	putchar('\n');
+
+	/* Handle first from jump, of which we don't know the entry. */
+	len = grab_bb(buffer, br->entries[nr-1].from,
+			br->entries[nr-1].from,
+			machine, thread, &x.is64bit, &x.cpumode);
+	if (len > 0) {
+		print_ip_sym(thread, x.cpumode, x.cpu,
+			     br->entries[nr - 1].from,
+			     &lastsym, attr);
+		print_jump(br->entries[nr - 1].from, &br->entries[nr - 1],
+			&x, buffer, len, 0);
+	}
+
+	/* Print all blocks */
+	for (i = nr - 2; i >= 0; i--) {
+		if (br->entries[i].from || br->entries[i].to)
+			pr_debug("%d: %" PRIx64 "-%" PRIx64 "\n", i,
+				 br->entries[i].from,
+				 br->entries[i].to);
+		start = br->entries[i + 1].to;
+		end = br->entries[i].from;
+
+		len = grab_bb(buffer, start, end,
+				machine, thread, &x.is64bit,
+				&x.cpumode);
+		/* Patch up missing kernel transfers due to ring filters */
+		if (len == -ENXIO && i > 0) {
+			end = br->entries[--i].from;
+			pr_debug("\tpatching up to %" PRIx64 "-%" PRIx64 "\n",
+					start, end);
+			len = grab_bb(buffer, start, end,
+				      machine, thread, &x.is64bit,
+				      &x.cpumode);
+		}
+		if (len <= 0)
+			continue;
+
+		insn = 0;
+		for (off = 0;; off += ilen) {
+			uint64_t ip = start + off;
+
+			print_ip_sym(thread, x.cpumode, x.cpu,
+				     ip,
+				     &lastsym, attr);
+			if (ip == end) {
+				print_jump(ip, &br->entries[i], &x,
+					   buffer + off,
+					   len - off, insn);
+				break;
+			} else {
+				printf("\t%016" PRIx64 "\t%s\n", ip,
+					disas_inst(&x, ip, buffer + off,
+						   len - off, &ilen));
+				if (ilen == 0)
+					break;
+				insn++;
+			}
+		}
+	}
+
+	/*
+	 * Hit the branch? In this case we are already done, and the target
+	 * has not been executed yet.
+	 */
+	if (br->entries[0].from == sample->ip)
+		return;
+	if (br->entries[0].flags.abort)
+		return;
+
+	/*
+	 * Print final block upto sample
+	 */
+	start = br->entries[0].to;
+	end = sample->ip;
+	len = grab_bb(buffer, start, end, machine, thread, &x.is64bit,
+			&x.cpumode);
+	print_ip_sym(thread, x.cpumode, x.cpu,
+		     start,
+		     &lastsym, attr);
+	if (len <= 0) {
+		/* Print at least last IP if basic block did not work */
+		len = grab_bb(buffer, sample->ip, sample->ip,
+				machine, thread, &x.is64bit, &x.cpumode);
+		if (len <= 0)
+			return;
+
+		printf("\t%016" PRIx64 "\t%s\n", sample->ip,
+			disas_inst(&x, sample->ip, buffer, len, NULL));
+		return;
+	}
+	for (off = 0; off <= end - start; off += ilen) {
+		printf("\t%016" PRIx64 "\t%s\n", start + off,
+				disas_inst(&x, start + off, buffer + off,
+					   len - off, &ilen));
+		if (ilen == 0)
+			break;
+	}
+}
 
 static void print_sample_addr(struct perf_sample *sample,
 			  struct thread *thread,
@@ -689,6 +947,8 @@ static void print_insn(union perf_event *event,
 	}
 	if (PRINT_FIELD(ASM))
 		print_sample_asm(event, sample, thread, al, machine);
+	if (PRINT_FIELD(BRSTACKASM))
+		print_sample_brstackasm(sample, thread, attr, machine);
 }
 
 static void print_sample_bts(union perf_event *event,
@@ -2230,6 +2490,8 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 		    "Show the mmap events"),
 	OPT_BOOLEAN('\0', "show-switch-events", &script.show_switch_events,
 		    "Show context switch events (if recorded)"),
+	OPT_INTEGER(0, "max-blocks", &max_blocks,
+		    "Maximum number of code blocks to dump with brstackasm"),
 	OPT_BOOLEAN('f', "force", &file.force, "don't complain, do it"),
 	OPT_BOOLEAN(0, "ns", &nanosecs,
 		    "Use 9 decimal places when displaying time"),
-- 
2.9.3

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#1553880 — Re: [PATCH 4/4] perf, tools, script: Add brstackasm output for branch stacks

On Tue, Jan 03, 2017 at 01:00:29AM -0800, Andi Kleen wrote:

SNIP

> +		len = grab_bb(buffer, start, end,
> +				machine, thread, &x.is64bit,
> +				&x.cpumode);
> +		/* Patch up missing kernel transfers due to ring filters */

could you please provide more details on those ring filters? never heard of..

thanks,
jirka

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#1554624 — Re: [PATCH 4/4] perf, tools, script: Add brstackasm output for branch stacks

On Sun, Jan 08, 2017 at 03:19:49PM +0100, Jiri Olsa wrote:
> On Tue, Jan 03, 2017 at 01:00:29AM -0800, Andi Kleen wrote:
> 
> SNIP
> 
> > +		len = grab_bb(buffer, start, end,
> > +				machine, thread, &x.is64bit,
> > +				&x.cpumode);
> > +		/* Patch up missing kernel transfers due to ring filters */
> 
> could you please provide more details on those ring filters? never heard of..

This is the LBR filter exposed with the -j option (-j user or -j kernel) 

-Andi

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#1553882 — Re: [PATCH 4/4] perf, tools, script: Add brstackasm output for branch stacks

On Tue, Jan 03, 2017 at 01:00:29AM -0800, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
> 

SNIP

> ---
>  tools/perf/Documentation/perf-script.txt |  13 +-
>  tools/perf/builtin-script.c              | 262 +++++++++++++++++++++++++++++++
>  2 files changed, 273 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
> index 863579b4d2e2..9b3c0e58f315 100644
> --- a/tools/perf/Documentation/perf-script.txt
> +++ b/tools/perf/Documentation/perf-script.txt
> @@ -116,7 +116,7 @@ OPTIONS
>  --fields::
>          Comma separated list of fields to print. Options are:
>          comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff,
> -        srcline, period, iregs, brstack, brstacksym, flags, bpf-output, asm.
> +	srcline, period, iregs, brstack, brstacksym, flags, bpf-output, asm, brstackasm,

tab / space issue

jirka

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#1549630 — [PATCH 3/4] perf, tools, script: Add support for printing assembler

From: Andi Kleen <ak@linux.intel.com>

When dumping PT traces with perf script it is very useful to see the
assembler for each sample, so that it is easily possible to follow
the control flow.

As using objdump is difficult and inefficient from perf script this
patch uses the Intel xed library to implement assembler output.
The library can be downloaded from http://github.com/intelxed/xed

The previous version of this patch used udis86, but was
rejected because udis86 was unmaintained and a runtime dependency.
Using the recently released xed avoids both of these problems:
- XED is well maintained and used by many Intel tools
- XED is linked statically so there is no runtime dependency.

The library is probed as an external dependency in the usual way. Then perf
script calls into it when needed, and handles callbacks to resolve
symbols.

% perf record -e intel_pt//u true
% perf script -F sym,symoff,ip,asm --itrace=i0ns | head
     7fc7188b4190 _start+0x0	mov %rsp, %rdi
     7fc7188b4193 _start+0x3	call _dl_start
     7fc7188b7710 _dl_start+0x0	push %rbp
     7fc7188b7711 _dl_start+0x1	mov %rsp, %rbp
     7fc7188b7714 _dl_start+0x4	push %r15
     7fc7188b7716 _dl_start+0x6	push %r14
     7fc7188b7718 _dl_start+0x8	push %r13
     7fc7188b771a _dl_start+0xa	push %r12
     7fc7188b771c _dl_start+0xc	mov %rdi, %r12
     7fc7188b771f _dl_start+0xf	push %rbx

v2:
Converted to use XED instead of udis86.
Separate disassembler interface into separate arch specific file.
Lots of cleanups and improvements.

Cc: adrian.hunter@intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 tools/perf/Documentation/perf-script.txt |  4 +-
 tools/perf/builtin-script.c              | 72 +++++++++++++++++++++++++++-----
 2 files changed, 64 insertions(+), 12 deletions(-)

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index 5dc5c6a09ac4..863579b4d2e2 100644
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -116,7 +116,7 @@ OPTIONS
 --fields::
         Comma separated list of fields to print. Options are:
         comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff,
-        srcline, period, iregs, brstack, brstacksym, flags, bpf-output,
+        srcline, period, iregs, brstack, brstacksym, flags, bpf-output, asm.
         callindent, insn, insnlen. Field list can be prepended with the type, trace, sw or hw,
         to indicate to which event type the field list applies.
         e.g., -F sw:comm,tid,time,ip,sym  and -F trace:time,cpu,trace
@@ -198,6 +198,8 @@ OPTIONS
 
 	The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.
 
+	When asm is specified the assembler instruction of each sample is printed in disassembled form.
+
 -k::
 --vmlinux=<file>::
         vmlinux pathname
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 2f3ff69fc4e7..e96668b1cc63 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -28,6 +28,7 @@
 #include <linux/time64.h>
 #include "asm/bug.h"
 #include "util/mem-events.h"
+#include "util/dis.h"
 
 static char const		*script_name;
 static char const		*generate_script_lang;
@@ -69,6 +70,7 @@ enum perf_output_field {
 	PERF_OUTPUT_CALLINDENT	    = 1U << 20,
 	PERF_OUTPUT_INSN	    = 1U << 21,
 	PERF_OUTPUT_INSNLEN	    = 1U << 22,
+	PERF_OUTPUT_ASM		    = 1U << 23,
 };
 
 struct output_option {
@@ -98,6 +100,7 @@ struct output_option {
 	{.str = "callindent", .field = PERF_OUTPUT_CALLINDENT},
 	{.str = "insn", .field = PERF_OUTPUT_INSN},
 	{.str = "insnlen", .field = PERF_OUTPUT_INSNLEN},
+	{.str = "asm", .field = PERF_OUTPUT_ASM},
 };
 
 /* default set to maintain compatibility with current format */
@@ -292,7 +295,11 @@ static int perf_evsel__check_attr(struct perf_evsel *evsel,
 		       "selected. Hence, no address to lookup the source line number.\n");
 		return -EINVAL;
 	}
-
+	if (PRINT_FIELD(ASM) && !PRINT_FIELD(IP)) {
+		pr_err("Display of assembler requested but sample IP is not\n"
+		       "selected.\n");
+		return -EINVAL;
+	}
 	if ((PRINT_FIELD(PID) || PRINT_FIELD(TID)) &&
 		perf_evsel__check_stype(evsel, PERF_SAMPLE_TID, "TID",
 					PERF_OUTPUT_TID|PERF_OUTPUT_PID))
@@ -436,6 +443,39 @@ static void print_sample_iregs(struct perf_sample *sample,
 	}
 }
 
+static void print_sample_asm(union perf_event *event,
+			     struct perf_sample *sample,
+			     struct thread *thread,
+			     struct addr_location *al,
+			     struct machine *machine)
+{
+	struct perf_dis x;
+	u8 buffer[32];
+	int len;
+	u64 offset;
+
+	x.thread = thread;
+	x.cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
+	x.cpu = sample->cpu;
+
+	if (!al->map || !al->map->dso)
+		return;
+	if (al->map->dso->data.status == DSO_DATA_STATUS_ERROR)
+		return;
+
+	/* Load maps to ensure dso->is_64_bit has been updated */
+	map__load(al->map);
+	x.is64bit = al->map->dso->is_64_bit;
+
+	offset = al->map->map_ip(al->map, sample->ip);
+	len = dso__data_read_offset(al->map->dso, machine,
+				    offset, buffer, MAXINSN);
+	if (len <= 0)
+		return;
+
+	printf("\t%s", disas_inst(&x, sample->ip, buffer, len, NULL));
+}
+
 static void print_sample_start(struct perf_sample *sample,
 			       struct thread *thread,
 			       struct perf_evsel *evsel)
@@ -631,8 +671,12 @@ static void print_sample_callindent(struct perf_sample *sample,
 		printf("%*s", spacing - len, "");
 }
 
-static void print_insn(struct perf_sample *sample,
-		       struct perf_event_attr *attr)
+static void print_insn(union perf_event *event,
+		       struct perf_sample *sample,
+		       struct perf_event_attr *attr,
+		       struct thread *thread,
+		       struct addr_location *al,
+		       struct machine *machine)
 {
 	if (PRINT_FIELD(INSNLEN))
 		printf(" ilen: %d", sample->insn_len);
@@ -643,12 +687,16 @@ static void print_insn(struct perf_sample *sample,
 		for (i = 0; i < sample->insn_len; i++)
 			printf(" %02x", (unsigned char)sample->insn[i]);
 	}
+	if (PRINT_FIELD(ASM))
+		print_sample_asm(event, sample, thread, al, machine);
 }
 
-static void print_sample_bts(struct perf_sample *sample,
+static void print_sample_bts(union perf_event *event,
+			     struct perf_sample *sample,
 			     struct perf_evsel *evsel,
 			     struct thread *thread,
-			     struct addr_location *al)
+			     struct addr_location *al,
+			     struct machine *machine)
 {
 	struct perf_event_attr *attr = &evsel->attr;
 	bool print_srcline_last = false;
@@ -689,7 +737,7 @@ static void print_sample_bts(struct perf_sample *sample,
 	if (print_srcline_last)
 		map__fprintf_srcline(al->map, al->addr, "\n  ", stdout);
 
-	print_insn(sample, attr);
+	print_insn(event, sample, attr, thread, al, machine);
 
 	printf("\n");
 }
@@ -871,7 +919,9 @@ static size_t data_src__printf(u64 data_src)
 
 static void process_event(struct perf_script *script,
 			  struct perf_sample *sample, struct perf_evsel *evsel,
-			  struct addr_location *al)
+			  struct addr_location *al,
+			  struct machine *machine,
+			  union perf_event *event)
 {
 	struct thread *thread = al->thread;
 	struct perf_event_attr *attr = &evsel->attr;
@@ -898,7 +948,7 @@ static void process_event(struct perf_script *script,
 		print_sample_flags(sample->flags);
 
 	if (is_bts_event(attr)) {
-		print_sample_bts(sample, evsel, thread, al);
+		print_sample_bts(event, sample, evsel, thread, al, machine);
 		return;
 	}
 
@@ -936,7 +986,7 @@ static void process_event(struct perf_script *script,
 
 	if (perf_evsel__is_bpf_output(evsel) && PRINT_FIELD(BPF_OUTPUT))
 		print_sample_bpf_output(sample);
-	print_insn(sample, attr);
+	print_insn(event, sample, attr, thread, al, machine);
 	printf("\n");
 }
 
@@ -1046,7 +1096,7 @@ static int process_sample_event(struct perf_tool *tool,
 	if (scripting_ops)
 		scripting_ops->process_event(event, sample, evsel, &al);
 	else
-		process_event(scr, sample, evsel, &al);
+		process_event(scr, sample, evsel, &al, machine, event);
 
 out_put:
 	addr_location__put(&al);
@@ -2152,7 +2202,7 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 		     "Valid types: hw,sw,trace,raw. "
 		     "Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,"
 		     "addr,symoff,period,iregs,brstack,brstacksym,flags,"
-		     "bpf-output,callindent,insn,insnlen", parse_output_fields),
+		     "bpf-output,callindent,insn,insnlen,asm", parse_output_fields),
 	OPT_BOOLEAN('a', "all-cpus", &system_wide,
 		    "system-wide collection from all CPUs"),
 	OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
-- 
2.9.3

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#1553886

On Tue, Jan 03, 2017 at 01:00:25AM -0800, Andi Kleen wrote:
> A native disassembler in perf is very useful, in particular with perf script to trace 
> instruction streams, but also for other analysis. Previously I attempted
> to do this using the udis86 library, but that was rejected because:
> - udis86 was not maintained anymore and lacking recent instructions
> - udis86 is dynamically linked and gives a runtime dependency.
> Doing this needs a full disassembler, not just a decoder, so the existing
> instruction decoder cannot be used without major changes.
> 
> This patchkit addresses these issues.  Intel recently released an open source version
> of the XED disassembler library, which is used in many other Intel software.
> It is very well maintained, uptodate, and supports static linking, so there is no
> runtime dependency. This version adds XED support to perf, and uses it to implement
> assembler output in perf script. It also fixes a range of issues in the previous
> version, see the individual change logs.
> 
> Available in 
> git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-misc.git perf/xed-3
> 
> v1: First post of XED version

I tested and it looks ok.. once the xed detection is sorted out
I'd ack it

thanks,
jirka

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