[GIT PULL 0/6] perf/core improvements and fixes

[GIT PULL 0/6] perf/core improvements and fixes

[Arnaldo Carvalho de Melo]

Hi Ingo,

	Please consider pulling,

- Arnaldo

The following changes since commit bac2e4a96d1c0bcce5e9654dcc902f75576b9b03:

  Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core (2015-08-31 10:25:46 +0200)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-core-for-mingo

for you to fetch changes up to bcc84ec65ad1bd9f777a1fade6f8e5e0c5808fa5:

  perf record: Add ability to name registers to record (2015-08-31 18:01:33 -0300)

----------------------------------------------------------------
perf/core improvements and fixes:

User visible:

- Add ability to specify to select which registers to record,
  to reduce the size of perf.data files, and also allow printing
  the registers in 'perf script': (Stephane Eranian)

    # perf record --intr-regs=AX,SP usleep 1
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.016 MB perf.data (8 samples) ]
    # perf script -F ip,sym,iregs | tail -5
     ffffffff8105f42a native_write_msr_safe   AX:0xf    SP:0xffff8802629c3c00
     ffffffff8105f42a native_write_msr_safe   AX:0xf    SP:0xffff8802629c3c00
     ffffffff81761ac0 _raw_spin_lock   AX:0xffff8801bfcf8020    SP:0xffff8802629c3ce8
     ffffffff81202bf8 __vma_adjust_trans_huge   AX:0x7ffc75200000    SP:0xffff8802629c3b30
     ffffffff8122b089 dput   AX:0x101    SP:0xffff8802629c3c78
    #

Infrastructure:

- Open event on evsel cpus and threads (Kan Liang)

- New bpf API to get name from a BPF object (Wang Nan)

Build fixes:

- Fix build on powerpc broken by pt/bts (Adrian Hunter)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

----------------------------------------------------------------
Adrian Hunter (1):
      perf tools: Fix build on powerpc broken by pt/bts

Kan Liang (1):
      perf evlist: Open event on evsel cpus and threads

Stephane Eranian (3):
      perf script: Enable printing of interrupted machine state
      perf/x86: Add list of register names
      perf record: Add ability to name registers to record

Wang Nan (1):
      bpf tools: New API to get name from a BPF object

 tools/lib/bpf/libbpf.c                             | 25 +++++++-
 tools/lib/bpf/libbpf.h                             |  4 +-
 tools/perf/Documentation/perf-record.txt           |  6 +-
 tools/perf/Documentation/perf-script.txt           |  2 +-
 tools/perf/arch/x86/util/Build                     |  1 +
 tools/perf/arch/x86/util/perf_regs.c               | 30 +++++++++
 tools/perf/builtin-record.c                        |  9 ++-
 tools/perf/builtin-script.c                        | 31 +++++++++-
 tools/perf/perf.h                                  |  2 +-
 tools/perf/tests/llvm.c                            |  2 +-
 tools/perf/util/Build                              |  2 +
 tools/perf/util/evlist.c                           |  4 ++
 tools/perf/util/evsel.c                            |  2 +-
 .../util/intel-pt-decoder/intel-pt-insn-decoder.c  |  3 +
 tools/perf/util/parse-regs-options.c               | 71 ++++++++++++++++++++++
 tools/perf/util/parse-regs-options.h               |  5 ++
 tools/perf/util/perf_regs.h                        |  7 +++
 17 files changed, 193 insertions(+), 13 deletions(-)
 create mode 100644 tools/perf/arch/x86/util/perf_regs.c
 create mode 100644 tools/perf/util/parse-regs-options.c
 create mode 100644 tools/perf/util/parse-regs-options.h

[PATCH 1/6] perf tools: Fix build on powerpc broken by pt/bts

[Arnaldo Carvalho de Melo]

From: Adrian Hunter <adrian.hunter@intel.com>

It is theoretically possible to process perf.data files created on x86
and that contain Intel PT or Intel BTS data, on any other architecture,
which is why it is possible for there to be build errors on powerpc
caused by pt/bts.

The errors were:

	util/intel-pt-decoder/intel-pt-insn-decoder.c: In function ‘intel_pt_insn_decoder’:
	util/intel-pt-decoder/intel-pt-insn-decoder.c:138:3: error: switch missing default case [-Werror=switch-default]
	   switch (insn->immediate.nbytes) {
	   ^
	cc1: all warnings being treated as errors

	linux-acme.git/tools/perf/perf-obj/libperf.a(libperf-in.o): In function `intel_pt_synth_branch_sample':
	sources/linux-acme.git/tools/perf/util/intel-pt.c:871: undefined reference to `tsc_to_perf_time'
	linux-acme.git/tools/perf/perf-obj/libperf.a(libperf-in.o): In function `intel_pt_sample':
	sources/linux-acme.git/tools/perf/util/intel-pt.c:915: undefined reference to `tsc_to_perf_time'
	sources/linux-acme.git/tools/perf/util/intel-pt.c:962: undefined reference to `tsc_to_perf_time'
	linux-acme.git/tools/perf/perf-obj/libperf.a(libperf-in.o): In function `intel_pt_process_event':
	sources/linux-acme.git/tools/perf/util/intel-pt.c:1454: undefined reference to `perf_time_to_tsc'

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441046384-28663-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/Build                                    | 1 +
 tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index e912856cc4e5..e79e4522368a 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -75,6 +75,7 @@ libperf-y += record.o
 libperf-y += srcline.o
 libperf-y += data.o
 libperf-$(CONFIG_X86) += tsc.o
+libperf-$(CONFIG_AUXTRACE) += tsc.o
 libperf-y += cloexec.o
 libperf-y += thread-stack.o
 libperf-$(CONFIG_AUXTRACE) += auxtrace.o
diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c
index 9e4eb8fcd559..d23138c06665 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c
@@ -146,6 +146,9 @@ static void intel_pt_insn_decoder(struct insn *insn,
 		case 4:
 			intel_pt_insn->rel = bswap_32(insn->immediate.value);
 			break;
+		default:
+			intel_pt_insn->rel = 0;
+			break;
 		}
 #else
 		intel_pt_insn->rel = insn->immediate.value;
-- 
2.1.0

[PATCH 2/6] bpf tools: New API to get name from a BPF object

[Arnaldo Carvalho de Melo]

From: Wang Nan <wangnan0@huawei.com>

Before this patch there's no way to connect a loaded bpf object
to its source file. However, during applying perf's '--filter' to BPF
object, without this connection makes things harder, because perf loads
all programs together, but '--filter' setting is for each object.

The API of bpf_object__open_buffer() is changed to allow passing a name.
Fortunately, at this time there's only one user of it (perf test LLVM),
so we change it together.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440742821-44548-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/bpf/libbpf.c  | 25 ++++++++++++++++++++++---
 tools/lib/bpf/libbpf.h  |  4 +++-
 tools/perf/tests/llvm.c |  2 +-
 3 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4fa4bc4505f5..4252fc22f78f 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -880,15 +880,26 @@ struct bpf_object *bpf_object__open(const char *path)
 }
 
 struct bpf_object *bpf_object__open_buffer(void *obj_buf,
-					   size_t obj_buf_sz)
+					   size_t obj_buf_sz,
+					   const char *name)
 {
+	char tmp_name[64];
+
 	/* param validation */
 	if (!obj_buf || obj_buf_sz <= 0)
 		return NULL;
 
-	pr_debug("loading object from buffer\n");
+	if (!name) {
+		snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx",
+			 (unsigned long)obj_buf,
+			 (unsigned long)obj_buf_sz);
+		tmp_name[sizeof(tmp_name) - 1] = '\0';
+		name = tmp_name;
+	}
+	pr_debug("loading object '%s' from buffer\n",
+		 name);
 
-	return __bpf_object__open("[buffer]", obj_buf, obj_buf_sz);
+	return __bpf_object__open(name, obj_buf, obj_buf_sz);
 }
 
 int bpf_object__unload(struct bpf_object *obj)
@@ -975,6 +986,14 @@ bpf_object__next(struct bpf_object *prev)
 	return next;
 }
 
+const char *
+bpf_object__get_name(struct bpf_object *obj)
+{
+	if (!obj)
+		return NULL;
+	return obj->path;
+}
+
 struct bpf_program *
 bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
 {
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index ea8adc206b62..f16170c95ffd 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -28,12 +28,14 @@ struct bpf_object;
 
 struct bpf_object *bpf_object__open(const char *path);
 struct bpf_object *bpf_object__open_buffer(void *obj_buf,
-					   size_t obj_buf_sz);
+					   size_t obj_buf_sz,
+					   const char *name);
 void bpf_object__close(struct bpf_object *object);
 
 /* Load/unload object into/from kernel */
 int bpf_object__load(struct bpf_object *obj);
 int bpf_object__unload(struct bpf_object *obj);
+const char *bpf_object__get_name(struct bpf_object *obj);
 
 struct bpf_object *bpf_object__next(struct bpf_object *prev);
 #define bpf_object__for_each_safe(pos, tmp)			\
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index a337356fd979..52d55971f66f 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -26,7 +26,7 @@ static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
 {
 	struct bpf_object *obj;
 
-	obj = bpf_object__open_buffer(obj_buf, obj_buf_sz);
+	obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, NULL);
 	if (!obj)
 		return -1;
 	bpf_object__close(obj);
-- 
2.1.0

[PATCH 3/6] perf evlist: Open event on evsel cpus and threads

[Arnaldo Carvalho de Melo]

From: Kan Liang <kan.liang@intel.com>

An evsel may have different cpus and threads than the evlist it is in.

Use it's own cpus and threads, when opening the evsel in 'perf record'.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1440138194-17001-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-record.c | 2 +-
 tools/perf/util/evlist.c    | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index a660022f2c92..1d14f382f614 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -279,7 +279,7 @@ static int record__open(struct record *rec)
 
 	evlist__for_each(evlist, pos) {
 try_again:
-		if (perf_evsel__open(pos, evlist->cpus, evlist->threads) < 0) {
+		if (perf_evsel__open(pos, pos->cpus, pos->threads) < 0) {
 			if (perf_evsel__fallback(pos, errno, msg, sizeof(msg))) {
 				if (verbose)
 					ui__warning("%s\n", msg);
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 8d00039d6a20..d51a5200c8af 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1181,6 +1181,10 @@ int perf_evlist__apply_filters(struct perf_evlist *evlist, struct perf_evsel **e
 		if (evsel->filter == NULL)
 			continue;
 
+		/*
+		 * filters only work for tracepoint event, which doesn't have cpu limit.
+		 * So evlist and evsel should always be same.
+		 */
 		err = perf_evsel__apply_filter(evsel, ncpus, nthreads, evsel->filter);
 		if (err) {
 			*err_evsel = evsel;
-- 
2.1.0

[PATCH 4/6] perf script: Enable printing of interrupted machine state

[Arnaldo Carvalho de Melo]

From: Stephane Eranian <eranian@google.com>

This patch adds the output of the interrupted machine state (iregs) to
perf script. It presents them  as NAME:VALUE so this is easy to parse
during post processing.

To capture the interrupted machine state:
   $ perf record -I ....

to display iregs, use the -F option:

   $ perf script -F ip,iregs
   40afc2   AX:0x6c5770    BX:0x1e    CX:0x5f4d80a    DX:0x101010101010101    SI:0x1

Signed-off-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1441039273-16260-2-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Documentation/perf-script.txt |  2 +-
 tools/perf/builtin-script.c              | 31 ++++++++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index 614b2c7b0293..dc3ec783b7bd 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, flags.
+	srcline, period, iregs, flags.
         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
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 4430340292c0..eb51325e8ad9 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -6,6 +6,7 @@
 #include "util/exec_cmd.h"
 #include "util/header.h"
 #include "util/parse-options.h"
+#include "util/perf_regs.h"
 #include "util/session.h"
 #include "util/tool.h"
 #include "util/symbol.h"
@@ -46,6 +47,7 @@ enum perf_output_field {
 	PERF_OUTPUT_SYMOFFSET       = 1U << 11,
 	PERF_OUTPUT_SRCLINE         = 1U << 12,
 	PERF_OUTPUT_PERIOD          = 1U << 13,
+	PERF_OUTPUT_IREGS	    = 1U << 14,
 };
 
 struct output_option {
@@ -66,6 +68,7 @@ struct output_option {
 	{.str = "symoff", .field = PERF_OUTPUT_SYMOFFSET},
 	{.str = "srcline", .field = PERF_OUTPUT_SRCLINE},
 	{.str = "period", .field = PERF_OUTPUT_PERIOD},
+	{.str = "iregs", .field = PERF_OUTPUT_IREGS},
 };
 
 /* default set to maintain compatibility with current format */
@@ -255,6 +258,11 @@ static int perf_evsel__check_attr(struct perf_evsel *evsel,
 					PERF_OUTPUT_PERIOD))
 		return -EINVAL;
 
+	if (PRINT_FIELD(IREGS) &&
+		perf_evsel__check_stype(evsel, PERF_SAMPLE_REGS_INTR, "IREGS",
+					PERF_OUTPUT_IREGS))
+		return -EINVAL;
+
 	return 0;
 }
 
@@ -352,6 +360,24 @@ out:
 	return 0;
 }
 
+static void print_sample_iregs(union perf_event *event __maybe_unused,
+			  struct perf_sample *sample,
+			  struct thread *thread __maybe_unused,
+			  struct perf_event_attr *attr)
+{
+	struct regs_dump *regs = &sample->intr_regs;
+	uint64_t mask = attr->sample_regs_intr;
+	unsigned i = 0, r;
+
+	if (!regs)
+		return;
+
+	for_each_set_bit(r, (unsigned long *) &mask, sizeof(mask) * 8) {
+		u64 val = regs->regs[i++];
+		printf("%5s:0x%"PRIx64" ", perf_reg_name(r), val);
+	}
+}
+
 static void print_sample_start(struct perf_sample *sample,
 			       struct thread *thread,
 			       struct perf_evsel *evsel)
@@ -525,6 +551,9 @@ static void process_event(union perf_event *event, struct perf_sample *sample,
 				     PERF_MAX_STACK_DEPTH);
 	}
 
+	if (PRINT_FIELD(IREGS))
+		print_sample_iregs(event, sample, thread, attr);
+
 	printf("\n");
 }
 
@@ -1643,7 +1672,7 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 		     "comma separated output fields prepend with 'type:'. "
 		     "Valid types: hw,sw,trace,raw. "
 		     "Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,"
-		     "addr,symoff,period,flags", parse_output_fields),
+		     "addr,symoff,period,iregs,flags", 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...]",
-- 
2.1.0

[PATCH 5/6] perf/x86: Add list of register names

[Arnaldo Carvalho de Melo]

From: Stephane Eranian <eranian@google.com>

This patch adds a way to locate a register identifier (PERF_X86_REG_*)
based on its name, e.g., AX.

This will be used by a subsequent patch to improved flexibility of perf
record.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1441039273-16260-3-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/arch/x86/util/Build       |  1 +
 tools/perf/arch/x86/util/perf_regs.c | 30 ++++++++++++++++++++++++++++++
 tools/perf/util/perf_regs.h          |  7 +++++++
 3 files changed, 38 insertions(+)
 create mode 100644 tools/perf/arch/x86/util/perf_regs.c

diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build
index 2c55e1b336c5..ff63649fa9ac 100644
--- a/tools/perf/arch/x86/util/Build
+++ b/tools/perf/arch/x86/util/Build
@@ -2,6 +2,7 @@ libperf-y += header.o
 libperf-y += tsc.o
 libperf-y += pmu.o
 libperf-y += kvm-stat.o
+libperf-y += perf_regs.o
 
 libperf-$(CONFIG_DWARF) += dwarf-regs.o
 
diff --git a/tools/perf/arch/x86/util/perf_regs.c b/tools/perf/arch/x86/util/perf_regs.c
new file mode 100644
index 000000000000..087c84ef5234
--- /dev/null
+++ b/tools/perf/arch/x86/util/perf_regs.c
@@ -0,0 +1,30 @@
+#include "../../perf.h"
+#include "../../util/perf_regs.h"
+
+#define REG(n, b) { .name = #n, .mask = 1ULL << (b) }
+#define REG_END { .name = NULL }
+const struct sample_reg sample_reg_masks[] = {
+	REG(AX, PERF_REG_X86_AX),
+	REG(BX, PERF_REG_X86_BX),
+	REG(CX, PERF_REG_X86_CX),
+	REG(DX, PERF_REG_X86_DX),
+	REG(SI, PERF_REG_X86_SI),
+	REG(DI, PERF_REG_X86_DI),
+	REG(BP, PERF_REG_X86_BP),
+	REG(SP, PERF_REG_X86_SP),
+	REG(IP, PERF_REG_X86_IP),
+	REG(FLAGS, PERF_REG_X86_FLAGS),
+	REG(CS, PERF_REG_X86_CS),
+	REG(SS, PERF_REG_X86_SS),
+#ifdef HAVE_ARCH_X86_64_SUPPORT
+	REG(R8, PERF_REG_X86_R8),
+	REG(R9, PERF_REG_X86_R9),
+	REG(R10, PERF_REG_X86_R10),
+	REG(R11, PERF_REG_X86_R11),
+	REG(R12, PERF_REG_X86_R12),
+	REG(R13, PERF_REG_X86_R13),
+	REG(R14, PERF_REG_X86_R14),
+	REG(R15, PERF_REG_X86_R15),
+#endif
+	REG_END
+};
diff --git a/tools/perf/util/perf_regs.h b/tools/perf/util/perf_regs.h
index 980dbf76bc98..92c1fff2153e 100644
--- a/tools/perf/util/perf_regs.h
+++ b/tools/perf/util/perf_regs.h
@@ -5,6 +5,13 @@
 
 struct regs_dump;
 
+struct sample_reg {
+	const char *name;
+	uint64_t mask;
+};
+
+extern const struct sample_reg sample_reg_masks[];
+
 #ifdef HAVE_PERF_REGS_SUPPORT
 #include <perf_regs.h>
 
-- 
2.1.0

[PATCH 6/6] perf record: Add ability to name registers to record

[Arnaldo Carvalho de Melo]

From: Stephane Eranian <eranian@google.com>

This patch modifies the -I/--int-regs option to enablepassing the name
of the registers to sample on interrupt. Registers can be specified by
their symbolic names. For instance on x86, --intr-regs=ax,si.

The motivation is to reduce the size of the perf.data file and the
overhead of sampling by only collecting the registers useful to a
specific analysis. For instance, for value profiling, sampling only the
registers used to passed arguements to functions.

With no parameter, the --intr-regs still records all possible registers
based on the architecture.

To name registers, it is necessary to use the long form of the option,
i.e., --intr-regs:

  $ perf record --intr-regs=si,di,r8,r9 .....

To record any possible registers:

  $ perf record -I .....
  $ perf report --intr-regs ...

To display the register, one can use perf report -D

To list the available registers:

  $ perf record --intr-regs=\?
  available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11 R12 R13 R14 R15

Signed-off-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1441039273-16260-4-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Documentation/perf-record.txt |  6 ++-
 tools/perf/builtin-record.c              |  7 +++-
 tools/perf/perf.h                        |  2 +-
 tools/perf/util/Build                    |  1 +
 tools/perf/util/evsel.c                  |  2 +-
 tools/perf/util/parse-regs-options.c     | 71 ++++++++++++++++++++++++++++++++
 tools/perf/util/parse-regs-options.h     |  5 +++
 7 files changed, 89 insertions(+), 5 deletions(-)
 create mode 100644 tools/perf/util/parse-regs-options.c
 create mode 100644 tools/perf/util/parse-regs-options.h

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 347a27322ed8..2e9ce77b5e14 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -276,7 +276,11 @@ filter out the startup phase of the program, which is often very different.
 --intr-regs::
 Capture machine state (registers) at interrupt, i.e., on counter overflows for
 each sample. List of captured registers depends on the architecture. This option
-is off by default.
+is off by default. It is possible to select the registers to sample using their
+symbolic names, e.g. on x86, ax, si. To list the available registers use
+--intr-regs=\?. To name registers, pass a comma separated list such as
+--intr-regs=ax,bx. The list of register is architecture dependent.
+
 
 --running-time::
 Record running and enabled time for read events (:S)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 1d14f382f614..142eeb341b29 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -27,8 +27,10 @@
 #include "util/cpumap.h"
 #include "util/thread_map.h"
 #include "util/data.h"
+#include "util/perf_regs.h"
 #include "util/auxtrace.h"
 #include "util/parse-branch-options.h"
+#include "util/parse-regs-options.h"
 
 #include <unistd.h>
 #include <sched.h>
@@ -1080,8 +1082,9 @@ struct option __record_options[] = {
 		    "sample transaction flags (special events only)"),
 	OPT_BOOLEAN(0, "per-thread", &record.opts.target.per_thread,
 		    "use per-thread mmaps"),
-	OPT_BOOLEAN('I', "intr-regs", &record.opts.sample_intr_regs,
-		    "Sample machine registers on interrupt"),
+	OPT_CALLBACK_OPTARG('I', "intr-regs", &record.opts.sample_intr_regs, NULL, "any register",
+		    "sample selected machine registers on interrupt,"
+		    " use -I ? to list register names", parse_regs),
 	OPT_BOOLEAN(0, "running-time", &record.opts.running_time,
 		    "Record running/enabled time of read (:S) events"),
 	OPT_CALLBACK('k', "clockid", &record.opts,
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index cccb4cf575d3..90129accffbe 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -54,7 +54,6 @@ struct record_opts {
 	bool	     sample_time_set;
 	bool	     callgraph_set;
 	bool	     period;
-	bool	     sample_intr_regs;
 	bool	     running_time;
 	bool	     full_auxtrace;
 	bool	     auxtrace_snapshot_mode;
@@ -64,6 +63,7 @@ struct record_opts {
 	unsigned int auxtrace_mmap_pages;
 	unsigned int user_freq;
 	u64          branch_stack;
+	u64	     sample_intr_regs;
 	u64	     default_interval;
 	u64	     user_interval;
 	size_t	     auxtrace_snapshot_size;
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index e79e4522368a..349bc96ca1fe 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -83,6 +83,7 @@ libperf-$(CONFIG_AUXTRACE) += intel-pt-decoder/
 libperf-$(CONFIG_AUXTRACE) += intel-pt.o
 libperf-$(CONFIG_AUXTRACE) += intel-bts.o
 libperf-y += parse-branch-options.o
+libperf-y += parse-regs-options.o
 
 libperf-$(CONFIG_LIBELF) += symbol-elf.o
 libperf-$(CONFIG_LIBELF) += probe-file.o
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index bac25f41a751..c53f79123b37 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -787,7 +787,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 		perf_evsel__config_callgraph(evsel, opts, &callchain_param);
 
 	if (opts->sample_intr_regs) {
-		attr->sample_regs_intr = PERF_REGS_MASK;
+		attr->sample_regs_intr = opts->sample_intr_regs;
 		perf_evsel__set_sample_bit(evsel, REGS_INTR);
 	}
 
diff --git a/tools/perf/util/parse-regs-options.c b/tools/perf/util/parse-regs-options.c
new file mode 100644
index 000000000000..4f2c1c255d81
--- /dev/null
+++ b/tools/perf/util/parse-regs-options.c
@@ -0,0 +1,71 @@
+#include "perf.h"
+#include "util/util.h"
+#include "util/debug.h"
+#include "util/parse-options.h"
+#include "util/parse-regs-options.h"
+
+int
+parse_regs(const struct option *opt, const char *str, int unset)
+{
+	uint64_t *mode = (uint64_t *)opt->value;
+	const struct sample_reg *r;
+	char *s, *os = NULL, *p;
+	int ret = -1;
+
+	if (unset)
+		return 0;
+
+	/*
+	 * cannot set it twice
+	 */
+	if (*mode)
+		return -1;
+
+	/* str may be NULL in case no arg is passed to -I */
+	if (str) {
+		/* because str is read-only */
+		s = os = strdup(str);
+		if (!s)
+			return -1;
+
+		for (;;) {
+			p = strchr(s, ',');
+			if (p)
+				*p = '\0';
+
+			if (!strcmp(s, "?")) {
+				fprintf(stderr, "available registers: ");
+				for (r = sample_reg_masks; r->name; r++) {
+					fprintf(stderr, "%s ", r->name);
+				}
+				fputc('\n', stderr);
+				/* just printing available regs */
+				return -1;
+			}
+			for (r = sample_reg_masks; r->name; r++) {
+				if (!strcasecmp(s, r->name))
+					break;
+			}
+			if (!r->name) {
+				ui__warning("unknown register %s,"
+					    " check man page\n", s);
+				goto error;
+			}
+
+			*mode |= r->mask;
+
+			if (!p)
+				break;
+
+			s = p + 1;
+		}
+	}
+	ret = 0;
+
+	/* default to all possible regs */
+	if (*mode == 0)
+		*mode = PERF_REGS_MASK;
+error:
+	free(os);
+	return ret;
+}
diff --git a/tools/perf/util/parse-regs-options.h b/tools/perf/util/parse-regs-options.h
new file mode 100644
index 000000000000..7d762b188007
--- /dev/null
+++ b/tools/perf/util/parse-regs-options.h
@@ -0,0 +1,5 @@
+#ifndef _PERF_PARSE_REGS_OPTIONS_H
+#define _PERF_PARSE_REGS_OPTIONS_H 1
+struct option;
+int parse_regs(const struct option *opt, const char *str, int unset);
+#endif /* _PERF_PARSE_REGS_OPTIONS_H */
-- 
2.1.0

Re: [GIT PULL 0/6] perf/core improvements and fixes

[Ingo Molnar]

* Arnaldo Carvalho de Melo <acme@kernel.org> wrote:

> Hi Ingo,
> 
> 	Please consider pulling,
> 
> - Arnaldo
> 
> The following changes since commit bac2e4a96d1c0bcce5e9654dcc902f75576b9b03:
> 
>   Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core (2015-08-31 10:25:46 +0200)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-core-for-mingo
> 
> for you to fetch changes up to bcc84ec65ad1bd9f777a1fade6f8e5e0c5808fa5:
> 
>   perf record: Add ability to name registers to record (2015-08-31 18:01:33 -0300)
> 
> ----------------------------------------------------------------
> perf/core improvements and fixes:
> 
> User visible:
> 
> - Add ability to specify to select which registers to record,
>   to reduce the size of perf.data files, and also allow printing
>   the registers in 'perf script': (Stephane Eranian)
> 
>     # perf record --intr-regs=AX,SP usleep 1
>     [ perf record: Woken up 1 times to write data ]
>     [ perf record: Captured and wrote 0.016 MB perf.data (8 samples) ]
>     # perf script -F ip,sym,iregs | tail -5
>      ffffffff8105f42a native_write_msr_safe   AX:0xf    SP:0xffff8802629c3c00
>      ffffffff8105f42a native_write_msr_safe   AX:0xf    SP:0xffff8802629c3c00
>      ffffffff81761ac0 _raw_spin_lock   AX:0xffff8801bfcf8020    SP:0xffff8802629c3ce8
>      ffffffff81202bf8 __vma_adjust_trans_huge   AX:0x7ffc75200000    SP:0xffff8802629c3b30
>      ffffffff8122b089 dput   AX:0x101    SP:0xffff8802629c3c78
>     #
> 
> Infrastructure:
> 
> - Open event on evsel cpus and threads (Kan Liang)
> 
> - New bpf API to get name from a BPF object (Wang Nan)
> 
> Build fixes:
> 
> - Fix build on powerpc broken by pt/bts (Adrian Hunter)
> 
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> 
> ----------------------------------------------------------------
> Adrian Hunter (1):
>       perf tools: Fix build on powerpc broken by pt/bts
> 
> Kan Liang (1):
>       perf evlist: Open event on evsel cpus and threads
> 
> Stephane Eranian (3):
>       perf script: Enable printing of interrupted machine state
>       perf/x86: Add list of register names
>       perf record: Add ability to name registers to record
> 
> Wang Nan (1):
>       bpf tools: New API to get name from a BPF object
> 
>  tools/lib/bpf/libbpf.c                             | 25 +++++++-
>  tools/lib/bpf/libbpf.h                             |  4 +-
>  tools/perf/Documentation/perf-record.txt           |  6 +-
>  tools/perf/Documentation/perf-script.txt           |  2 +-
>  tools/perf/arch/x86/util/Build                     |  1 +
>  tools/perf/arch/x86/util/perf_regs.c               | 30 +++++++++
>  tools/perf/builtin-record.c                        |  9 ++-
>  tools/perf/builtin-script.c                        | 31 +++++++++-
>  tools/perf/perf.h                                  |  2 +-
>  tools/perf/tests/llvm.c                            |  2 +-
>  tools/perf/util/Build                              |  2 +
>  tools/perf/util/evlist.c                           |  4 ++
>  tools/perf/util/evsel.c                            |  2 +-
>  .../util/intel-pt-decoder/intel-pt-insn-decoder.c  |  3 +
>  tools/perf/util/parse-regs-options.c               | 71 ++++++++++++++++++++++
>  tools/perf/util/parse-regs-options.h               |  5 ++
>  tools/perf/util/perf_regs.h                        |  7 +++
>  17 files changed, 193 insertions(+), 13 deletions(-)
>  create mode 100644 tools/perf/arch/x86/util/perf_regs.c
>  create mode 100644 tools/perf/util/parse-regs-options.c
>  create mode 100644 tools/perf/util/parse-regs-options.h

Pulled into tip:perf/urgent, thanks a lot Arnaldo!

	Ingo