2023-05-11 08:00:37

by Yang Jihong

[permalink] [raw]
Subject: [PATCH v2 0/4] perf tools: Add printing perf_event_attr `config` and `id` symbol in perf_event_attr__fprintf()

Add printing perf_event_attr `config` and `id` symbol to improve the readability of debugging information.

Before:

# perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
<SNIP>
------------------------------------------------------------
perf_event_attr:
size 136
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
------------------------------------------------------------
perf_event_attr:
type 1
size 136
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
------------------------------------------------------------
perf_event_attr:
type 2
size 136
config 0x143
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
------------------------------------------------------------
perf_event_attr:
type 3
size 136
config 0x10005
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
------------------------------------------------------------
perf_event_attr:
type 4
size 136
config 0x101
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
------------------------------------------------------------
perf_event_attr:
type 5
size 136
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
bp_type 3
{ bp_len, config2 } 0x4
------------------------------------------------------------
<SNIP>

After:

# perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
<SNIP>
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
size 136
config 0 (PERF_COUNT_HW_CPU_CYCLES)
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 0 (PERF_COUNT_SW_CPU_CLOCK)
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
------------------------------------------------------------
perf_event_attr:
type 2 (PERF_TYPE_TRACEPOINT)
size 136
config 0x143 (sched:sched_switch)
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
------------------------------------------------------------
perf_event_attr:
type 3 (PERF_TYPE_HW_CACHE)
size 136
config 0x10005 (PERF_COUNT_HW_CACHE_RESULT_MISS | PERF_COUNT_HW_CACHE_OP_READ | PERF_COUNT_HW_CACHE_BPU)
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
------------------------------------------------------------
perf_event_attr:
type 4 (PERF_TYPE_RAW)
size 136
config 0x101
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
------------------------------------------------------------
perf_event_attr:
type 5 (PERF_TYPE_BREAKPOINT)
size 136
config 0
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
bp_type 3
{ bp_len, config2 } 0x4
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 11
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 9 (PERF_COUNT_SW_DUMMY)
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
inherit 1
mmap 1
comm 1
freq 1
task 1
sample_id_all 1
mmap2 1
comm_exec 1
ksymbol 1
bpf_event 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 12
<SNIP>

Yang Jihong (4):
perf trace-event-info: Add tracepoint_id_to_name() helper
perf tools: Extend PRINT_ATTRf to support printing of members with a
value of 0
perf tools: Add printing perf_event_attr type symbol in
perf_event_attr__fprintf()
perf tools: Add printing perf_event_attr config symbol in
perf_event_attr__fprintf()

tools/perf/util/perf_event_attr_fprintf.c | 203 +++++++++++++++++++++-
tools/perf/util/trace-event-info.c | 11 ++
tools/perf/util/trace-event.h | 6 +
3 files changed, 211 insertions(+), 9 deletions(-)

--

Changes since v1:
- Modify initialization of path in tracepoint_id_to_path().
- Replace snprintf&strdup with asprintf.
- Use switch/case to get stringified name for type and id.

2.30.GIT



2023-05-11 08:04:49

by Yang Jihong

[permalink] [raw]
Subject: [PATCH v2 3/4] perf tools: Add printing perf_event_attr type symbol in perf_event_attr__fprintf()

When printing perf_event_attr, always display perf_event_attr type and its symbol
to improve the readability of debugging information.

Before:

# perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
<SNIP>
------------------------------------------------------------
perf_event_attr:
size 136
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
------------------------------------------------------------
perf_event_attr:
type 1
size 136
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
------------------------------------------------------------
perf_event_attr:
type 2
size 136
config 0x143
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
------------------------------------------------------------
perf_event_attr:
type 3
size 136
config 0x10005
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
------------------------------------------------------------
perf_event_attr:
type 4
size 136
config 0x101
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
------------------------------------------------------------
perf_event_attr:
type 5
size 136
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
bp_type 3
{ bp_len, config2 } 0x4
------------------------------------------------------------
<SNIP>

After:

# perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
<SNIP>
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
size 136
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
------------------------------------------------------------
perf_event_attr:
type 2 (PERF_TYPE_TRACEPOINT)
size 136
config 0x143
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
------------------------------------------------------------
perf_event_attr:
type 3 (PERF_TYPE_HW_CACHE)
size 136
config 0x10005
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
------------------------------------------------------------
perf_event_attr:
type 4 (PERF_TYPE_RAW)
size 136
config 0x101
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
read_format ID
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
------------------------------------------------------------
perf_event_attr:
type 5 (PERF_TYPE_BREAKPOINT)
size 136
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|IDENTIFIER
read_format ID
disabled 1
inherit 1
sample_id_all 1
exclude_guest 1
bp_type 3
{ bp_len, config2 } 0x4
------------------------------------------------------------
<SNIP>

Signed-off-by: Yang Jihong <[email protected]>
---
tools/perf/util/perf_event_attr_fprintf.c | 30 ++++++++++++++++++++++-
1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
index 433029c6afc5..cd0905d8cb7a 100644
--- a/tools/perf/util/perf_event_attr_fprintf.c
+++ b/tools/perf/util/perf_event_attr_fprintf.c
@@ -71,6 +71,33 @@ static void __p_read_format(char *buf, size_t size, u64 value)
__p_bits(buf, size, value, bits);
}

+#define ENUM_ID_TO_STR_CASE(x) case x: return (#x);
+static const char *stringify_perf_type_id(u64 value)
+{
+ /* sync with enum perf_type_id in perf_event.h */
+ switch (value) {
+ ENUM_ID_TO_STR_CASE(PERF_TYPE_HARDWARE)
+ ENUM_ID_TO_STR_CASE(PERF_TYPE_SOFTWARE)
+ ENUM_ID_TO_STR_CASE(PERF_TYPE_TRACEPOINT)
+ ENUM_ID_TO_STR_CASE(PERF_TYPE_HW_CACHE)
+ ENUM_ID_TO_STR_CASE(PERF_TYPE_RAW)
+ ENUM_ID_TO_STR_CASE(PERF_TYPE_BREAKPOINT)
+ default:
+ return NULL;
+ }
+}
+#undef ENUM_ID_TO_STR_CASE
+
+static void __p_type_id(char *buf, size_t size, u64 value)
+{
+ const char *str = stringify_perf_type_id(value);
+
+ if (str == NULL)
+ snprintf(buf, size, "%"PRIu64, value);
+ else
+ snprintf(buf, size, "%"PRIu64" (%s)", value, str);
+}
+
#define BUF_SIZE 1024

#define p_hex(val) snprintf(buf, BUF_SIZE, "%#"PRIx64, (uint64_t)(val))
@@ -79,6 +106,7 @@ static void __p_read_format(char *buf, size_t size, u64 value)
#define p_sample_type(val) __p_sample_type(buf, BUF_SIZE, val)
#define p_branch_sample_type(val) __p_branch_sample_type(buf, BUF_SIZE, val)
#define p_read_format(val) __p_read_format(buf, BUF_SIZE, val)
+#define p_type_id(val) __p_type_id(buf, BUF_SIZE, val)

#define PRINT_ATTRn(_n, _f, _p, _a) \
do { \
@@ -96,7 +124,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
char buf[BUF_SIZE];
int ret = 0;

- PRINT_ATTRf(type, p_unsigned);
+ PRINT_ATTRn("type", type, p_type_id, true);
PRINT_ATTRf(size, p_unsigned);
PRINT_ATTRf(config, p_hex);
PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned, false);
--
2.30.GIT


2023-05-11 08:04:50

by Yang Jihong

[permalink] [raw]
Subject: [PATCH v2 1/4] perf trace-event-info: Add tracepoint_id_to_name() helper

Add tracepoint_id_to_name() helper to search for the trace events directory
by given event id and return the corresponding tracepoint.

Signed-off-by: Yang Jihong <[email protected]>
---
tools/perf/util/trace-event-info.c | 11 +++++++++++
tools/perf/util/trace-event.h | 6 ++++++
2 files changed, 17 insertions(+)

diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index c24b3a15e319..a5c65cb02a28 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -466,6 +466,17 @@ static struct tracepoint_path *tracepoint_id_to_path(u64 config)
return NULL;
}

+char *tracepoint_id_to_name(u64 config)
+{
+ char *buf = NULL;
+ struct tracepoint_path *path = tracepoint_id_to_path(config);
+
+ if ((path != NULL) && (asprintf(&buf, "%s:%s", path->system, path->name) > 0))
+ return buf;
+
+ return NULL;
+}
+
static struct tracepoint_path *tracepoint_name_to_path(const char *name)
{
struct tracepoint_path *path = zalloc(sizeof(*path));
diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h
index a0cff184b1cd..a69ee29419f3 100644
--- a/tools/perf/util/trace-event.h
+++ b/tools/perf/util/trace-event.h
@@ -62,6 +62,12 @@ unsigned long long eval_flag(const char *flag);

int read_tracing_data(int fd, struct list_head *pattrs);

+/*
+ * Return the tracepoint name in the format "subsystem:event_name",
+ * callers should free the returned string.
+ */
+char *tracepoint_id_to_name(u64 config);
+
struct tracing_data {
/* size is only valid if temp is 'true' */
ssize_t size;
--
2.30.GIT


2023-05-11 08:08:40

by Yang Jihong

[permalink] [raw]
Subject: [PATCH v2 2/4] perf tools: Extend PRINT_ATTRf to support printing of members with a value of 0

When printing attr, members whose value is 0 will not be printed, we want
to print the case where attr->type is 0(PERF_TYPE_HARDWARE), add `_a`
param to PRINT_ATTRf macro to always print member when it is true
No functional change.

Signed-off-by: Yang Jihong <[email protected]>
---
tools/perf/util/perf_event_attr_fprintf.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
index 7e5e7b30510d..433029c6afc5 100644
--- a/tools/perf/util/perf_event_attr_fprintf.c
+++ b/tools/perf/util/perf_event_attr_fprintf.c
@@ -80,15 +80,15 @@ static void __p_read_format(char *buf, size_t size, u64 value)
#define p_branch_sample_type(val) __p_branch_sample_type(buf, BUF_SIZE, val)
#define p_read_format(val) __p_read_format(buf, BUF_SIZE, val)

-#define PRINT_ATTRn(_n, _f, _p) \
+#define PRINT_ATTRn(_n, _f, _p, _a) \
do { \
- if (attr->_f) { \
+ if (_a || attr->_f) { \
_p(attr->_f); \
ret += attr__fprintf(fp, _n, buf, priv);\
} \
} while (0)

-#define PRINT_ATTRf(_f, _p) PRINT_ATTRn(#_f, _f, _p)
+#define PRINT_ATTRf(_f, _p) PRINT_ATTRn(#_f, _f, _p, false)

int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
attr__fprintf_f attr__fprintf, void *priv)
@@ -99,7 +99,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
PRINT_ATTRf(type, p_unsigned);
PRINT_ATTRf(size, p_unsigned);
PRINT_ATTRf(config, p_hex);
- PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned);
+ PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned, false);
PRINT_ATTRf(sample_type, p_sample_type);
PRINT_ATTRf(read_format, p_read_format);

@@ -141,10 +141,10 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
PRINT_ATTRf(remove_on_exec, p_unsigned);
PRINT_ATTRf(sigtrap, p_unsigned);

- PRINT_ATTRn("{ wakeup_events, wakeup_watermark }", wakeup_events, p_unsigned);
+ PRINT_ATTRn("{ wakeup_events, wakeup_watermark }", wakeup_events, p_unsigned, false);
PRINT_ATTRf(bp_type, p_unsigned);
- PRINT_ATTRn("{ bp_addr, config1 }", bp_addr, p_hex);
- PRINT_ATTRn("{ bp_len, config2 }", bp_len, p_hex);
+ PRINT_ATTRn("{ bp_addr, config1 }", bp_addr, p_hex, false);
+ PRINT_ATTRn("{ bp_len, config2 }", bp_len, p_hex, false);
PRINT_ATTRf(branch_sample_type, p_branch_sample_type);
PRINT_ATTRf(sample_regs_user, p_hex);
PRINT_ATTRf(sample_stack_user, p_unsigned);
--
2.30.GIT


2023-05-12 10:42:49

by Adrian Hunter

[permalink] [raw]
Subject: Re: [PATCH v2 1/4] perf trace-event-info: Add tracepoint_id_to_name() helper

On 11/05/23 10:51, Yang Jihong wrote:
> Add tracepoint_id_to_name() helper to search for the trace events directory
> by given event id and return the corresponding tracepoint.
>
> Signed-off-by: Yang Jihong <[email protected]>
> ---
> tools/perf/util/trace-event-info.c | 11 +++++++++++
> tools/perf/util/trace-event.h | 6 ++++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
> index c24b3a15e319..a5c65cb02a28 100644
> --- a/tools/perf/util/trace-event-info.c
> +++ b/tools/perf/util/trace-event-info.c
> @@ -466,6 +466,17 @@ static struct tracepoint_path *tracepoint_id_to_path(u64 config)
> return NULL;
> }
>
> +char *tracepoint_id_to_name(u64 config)
> +{
> + char *buf = NULL;
> + struct tracepoint_path *path = tracepoint_id_to_path(config);

It is considered slightly nicer to put local declarations
in descending order of line length. i.e.

struct tracepoint_path *path = tracepoint_id_to_path(config);
char *buf = NULL;

> +
> + if ((path != NULL) && (asprintf(&buf, "%s:%s", path->system, path->name) > 0))

The parentheses are unnecessary and kernel style tends to avoid "!= NULL"
i.e.

if (path && asprintf(&buf, "%s:%s", path->system, path->name) > 0)

> + return buf;
> +
> + return NULL;
> +}
> +
> static struct tracepoint_path *tracepoint_name_to_path(const char *name)
> {
> struct tracepoint_path *path = zalloc(sizeof(*path));
> diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h
> index a0cff184b1cd..a69ee29419f3 100644
> --- a/tools/perf/util/trace-event.h
> +++ b/tools/perf/util/trace-event.h
> @@ -62,6 +62,12 @@ unsigned long long eval_flag(const char *flag);
>
> int read_tracing_data(int fd, struct list_head *pattrs);
>
> +/*
> + * Return the tracepoint name in the format "subsystem:event_name",
> + * callers should free the returned string.
> + */
> +char *tracepoint_id_to_name(u64 config);
> +
> struct tracing_data {
> /* size is only valid if temp is 'true' */
> ssize_t size;


2023-05-12 10:49:28

by Adrian Hunter

[permalink] [raw]
Subject: Re: [PATCH v2 3/4] perf tools: Add printing perf_event_attr type symbol in perf_event_attr__fprintf()

On 11/05/23 10:51, Yang Jihong wrote:
> When printing perf_event_attr, always display perf_event_attr type and its symbol
> to improve the readability of debugging information.
>
> Before:
>
> # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
> <SNIP>
> ------------------------------------------------------------
> perf_event_attr:
> size 136
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
> ------------------------------------------------------------
> perf_event_attr:
> type 1
> size 136
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
> ------------------------------------------------------------
> perf_event_attr:
> type 2
> size 136
> config 0x143
> { sample_period, sample_freq } 1
> sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
> ------------------------------------------------------------
> perf_event_attr:
> type 3
> size 136
> config 0x10005
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
> ------------------------------------------------------------
> perf_event_attr:
> type 4
> size 136
> config 0x101
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
> ------------------------------------------------------------
> perf_event_attr:
> type 5
> size 136
> { sample_period, sample_freq } 1
> sample_type IP|TID|TIME|CPU|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> sample_id_all 1
> exclude_guest 1
> bp_type 3
> { bp_len, config2 } 0x4
> ------------------------------------------------------------
> <SNIP>
>
> After:
>
> # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
> <SNIP>
> ------------------------------------------------------------
> perf_event_attr:
> type 0 (PERF_TYPE_HARDWARE)
> size 136
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
> ------------------------------------------------------------
> perf_event_attr:
> type 1 (PERF_TYPE_SOFTWARE)
> size 136
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
> ------------------------------------------------------------
> perf_event_attr:
> type 2 (PERF_TYPE_TRACEPOINT)
> size 136
> config 0x143
> { sample_period, sample_freq } 1
> sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
> ------------------------------------------------------------
> perf_event_attr:
> type 3 (PERF_TYPE_HW_CACHE)
> size 136
> config 0x10005
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
> ------------------------------------------------------------
> perf_event_attr:
> type 4 (PERF_TYPE_RAW)
> size 136
> config 0x101
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
> ------------------------------------------------------------
> perf_event_attr:
> type 5 (PERF_TYPE_BREAKPOINT)
> size 136
> { sample_period, sample_freq } 1
> sample_type IP|TID|TIME|CPU|IDENTIFIER
> read_format ID
> disabled 1
> inherit 1
> sample_id_all 1
> exclude_guest 1
> bp_type 3
> { bp_len, config2 } 0x4
> ------------------------------------------------------------
> <SNIP>
>
> Signed-off-by: Yang Jihong <[email protected]>
> ---
> tools/perf/util/perf_event_attr_fprintf.c | 30 ++++++++++++++++++++++-
> 1 file changed, 29 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
> index 433029c6afc5..cd0905d8cb7a 100644
> --- a/tools/perf/util/perf_event_attr_fprintf.c
> +++ b/tools/perf/util/perf_event_attr_fprintf.c
> @@ -71,6 +71,33 @@ static void __p_read_format(char *buf, size_t size, u64 value)
> __p_bits(buf, size, value, bits);
> }
>
> +#define ENUM_ID_TO_STR_CASE(x) case x: return (#x);
> +static const char *stringify_perf_type_id(u64 value)
> +{
> + /* sync with enum perf_type_id in perf_event.h */

Everything in this file syncs with perf_event.h, so the comment
does not seem very useful.

> + switch (value) {
> + ENUM_ID_TO_STR_CASE(PERF_TYPE_HARDWARE)
> + ENUM_ID_TO_STR_CASE(PERF_TYPE_SOFTWARE)
> + ENUM_ID_TO_STR_CASE(PERF_TYPE_TRACEPOINT)
> + ENUM_ID_TO_STR_CASE(PERF_TYPE_HW_CACHE)
> + ENUM_ID_TO_STR_CASE(PERF_TYPE_RAW)
> + ENUM_ID_TO_STR_CASE(PERF_TYPE_BREAKPOINT)
> + default:
> + return NULL;
> + }
> +}
> +#undef ENUM_ID_TO_STR_CASE
> +
> +static void __p_type_id(char *buf, size_t size, u64 value)
> +{
> + const char *str = stringify_perf_type_id(value);
> +
> + if (str == NULL)
> + snprintf(buf, size, "%"PRIu64, value);
> + else
> + snprintf(buf, size, "%"PRIu64" (%s)", value, str);

These 4 lines end up getting used again about 3 times in the next
patch, so might as well be a separate function e.g.

print_id(buf, size, value, stringify_perf_type_id(value));

where:

static void print_id(char *buf, size_t size, u64 value, const char *str)
{
if (str == NULL)
snprintf(buf, size, "%"PRIu64, value);
else
snprintf(buf, size, "%"PRIu64" (%s)", value, str);
}

> +}
> +
> #define BUF_SIZE 1024
>
> #define p_hex(val) snprintf(buf, BUF_SIZE, "%#"PRIx64, (uint64_t)(val))
> @@ -79,6 +106,7 @@ static void __p_read_format(char *buf, size_t size, u64 value)
> #define p_sample_type(val) __p_sample_type(buf, BUF_SIZE, val)
> #define p_branch_sample_type(val) __p_branch_sample_type(buf, BUF_SIZE, val)
> #define p_read_format(val) __p_read_format(buf, BUF_SIZE, val)
> +#define p_type_id(val) __p_type_id(buf, BUF_SIZE, val)
>
> #define PRINT_ATTRn(_n, _f, _p, _a) \
> do { \
> @@ -96,7 +124,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
> char buf[BUF_SIZE];
> int ret = 0;
>
> - PRINT_ATTRf(type, p_unsigned);
> + PRINT_ATTRn("type", type, p_type_id, true);
> PRINT_ATTRf(size, p_unsigned);
> PRINT_ATTRf(config, p_hex);
> PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned, false);


2023-05-15 08:53:33

by Yang Jihong

[permalink] [raw]
Subject: Re: [PATCH v2 1/4] perf trace-event-info: Add tracepoint_id_to_name() helper

Hello,

On 2023/5/12 18:33, Adrian Hunter wrote:
> On 11/05/23 10:51, Yang Jihong wrote:
>> Add tracepoint_id_to_name() helper to search for the trace events directory
>> by given event id and return the corresponding tracepoint.
>>
>> Signed-off-by: Yang Jihong <[email protected]>
>> ---
>> tools/perf/util/trace-event-info.c | 11 +++++++++++
>> tools/perf/util/trace-event.h | 6 ++++++
>> 2 files changed, 17 insertions(+)
>>
>> diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
>> index c24b3a15e319..a5c65cb02a28 100644
>> --- a/tools/perf/util/trace-event-info.c
>> +++ b/tools/perf/util/trace-event-info.c
>> @@ -466,6 +466,17 @@ static struct tracepoint_path *tracepoint_id_to_path(u64 config)
>> return NULL;
>> }
>>
>> +char *tracepoint_id_to_name(u64 config)
>> +{
>> + char *buf = NULL;
>> + struct tracepoint_path *path = tracepoint_id_to_path(config);
>
> It is considered slightly nicer to put local declarations
> in descending order of line length. i.e.
OK, will fix in v3.
>
> struct tracepoint_path *path = tracepoint_id_to_path(config);
> char *buf = NULL;
>
>> +
>> + if ((path != NULL) && (asprintf(&buf, "%s:%s", path->system, path->name) > 0))
>
> The parentheses are unnecessary and kernel style tends to avoid "!= NULL"
> i.e.
OK, will fix in v3.

Thanks,
Yang

2023-05-15 08:59:40

by Adrian Hunter

[permalink] [raw]
Subject: Re: [PATCH v2 3/4] perf tools: Add printing perf_event_attr type symbol in perf_event_attr__fprintf()

On 15/05/23 11:48, Yang Jihong wrote:
> Hello,
>
> On 2023/5/12 18:34, Adrian Hunter wrote:
>> On 11/05/23 10:51, Yang Jihong wrote:
>>> When printing perf_event_attr, always display perf_event_attr type and its symbol
>>> to improve the readability of debugging information.
>>>
>>> Before:
>>>
>>>    # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>>>    <SNIP>
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      size                             136
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             1
>>>      size                             136
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 6
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             2
>>>      size                             136
>>>      config                           0x143
>>>      { sample_period, sample_freq }   1
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             3
>>>      size                             136
>>>      config                           0x10005
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 9
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             4
>>>      size                             136
>>>      config                           0x101
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 10
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             5
>>>      size                             136
>>>      { sample_period, sample_freq }   1
>>>      sample_type                      IP|TID|TIME|CPU|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>      bp_type                          3
>>>      { bp_len, config2 }              0x4
>>>    ------------------------------------------------------------
>>>    <SNIP>
>>>
>>> After:
>>>
>>>    # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>>>    <SNIP>
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             0 (PERF_TYPE_HARDWARE)
>>>      size                             136
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             1 (PERF_TYPE_SOFTWARE)
>>>      size                             136
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 6
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             2 (PERF_TYPE_TRACEPOINT)
>>>      size                             136
>>>      config                           0x143
>>>      { sample_period, sample_freq }   1
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             3 (PERF_TYPE_HW_CACHE)
>>>      size                             136
>>>      config                           0x10005
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 9
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             4 (PERF_TYPE_RAW)
>>>      size                             136
>>>      config                           0x101
>>>      { sample_period, sample_freq }   4000
>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      freq                             1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>    ------------------------------------------------------------
>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 10
>>>    ------------------------------------------------------------
>>>    perf_event_attr:
>>>      type                             5 (PERF_TYPE_BREAKPOINT)
>>>      size                             136
>>>      { sample_period, sample_freq }   1
>>>      sample_type                      IP|TID|TIME|CPU|IDENTIFIER
>>>      read_format                      ID
>>>      disabled                         1
>>>      inherit                          1
>>>      sample_id_all                    1
>>>      exclude_guest                    1
>>>      bp_type                          3
>>>      { bp_len, config2 }              0x4
>>>    ------------------------------------------------------------
>>>    <SNIP>
>>>
>>> Signed-off-by: Yang Jihong <[email protected]>
>>> ---
>>>   tools/perf/util/perf_event_attr_fprintf.c | 30 ++++++++++++++++++++++-
>>>   1 file changed, 29 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
>>> index 433029c6afc5..cd0905d8cb7a 100644
>>> --- a/tools/perf/util/perf_event_attr_fprintf.c
>>> +++ b/tools/perf/util/perf_event_attr_fprintf.c
>>> @@ -71,6 +71,33 @@ static void __p_read_format(char *buf, size_t size, u64 value)
>>>       __p_bits(buf, size, value, bits);
>>>   }
>>>   +#define ENUM_ID_TO_STR_CASE(x) case x: return (#x);
>>> +static const char *stringify_perf_type_id(u64 value)
>>> +{
>>> +    /* sync with enum perf_type_id in perf_event.h */
>>
>> Everything in this file syncs with perf_event.h, so the comment
>> does not seem very useful.
> OK, will fix in v3.
>>
>>> +    switch (value) {
>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_HARDWARE)
>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_SOFTWARE)
>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_TRACEPOINT)
>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_HW_CACHE)
>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_RAW)
>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_BREAKPOINT)
>>> +    default:
>>> +        return NULL;
>>> +    }
>>> +}
>>> +#undef ENUM_ID_TO_STR_CASE
>>> +
>>> +static void __p_type_id(char *buf, size_t size, u64 value)
>>> +{
>>> +    const char *str = stringify_perf_type_id(value);
>>> +
>>> +    if (str == NULL)
>>> +        snprintf(buf, size, "%"PRIu64, value);
>>> +    else
>>> +        snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>>
>> These 4 lines end up getting used again about 3 times in the next
>> patch, so might as well be a separate function e.g.
>>
>>     print_id(buf, size, value, stringify_perf_type_id(value));
>>
>> where:
>>
>> static void print_id(char *buf, size_t size, u64 value, const char *str)
>> {
>>     if (str == NULL)
>>         snprintf(buf, size, "%"PRIu64, value);
>>     else
>>         snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>> }
>>
> OK, will add print_id() helper in v3.
> If print_id() helper is also used to print config id, is printed in the decimal format. In the past, it is printed in the hexadecimal format,
> there may be some changes here.
>
> Before:
>   config                           0x143
>
> After:
>   config                           323 (sched:sched_switch)

Right I didn't notice the difference. Best keep print_id() just for the hex cases.

>
>>> +}
>>> +
>>>   #define BUF_SIZE        1024
>>>     #define p_hex(val)        snprintf(buf, BUF_SIZE, "%#"PRIx64, (uint64_t)(val))
>>> @@ -79,6 +106,7 @@ static void __p_read_format(char *buf, size_t size, u64 value)
>>>   #define p_sample_type(val)    __p_sample_type(buf, BUF_SIZE, val)
>>>   #define p_branch_sample_type(val) __p_branch_sample_type(buf, BUF_SIZE, val)
>>>   #define p_read_format(val)    __p_read_format(buf, BUF_SIZE, val)
>>> +#define p_type_id(val)        __p_type_id(buf, BUF_SIZE, val)
>>>     #define PRINT_ATTRn(_n, _f, _p, _a)            \
>>>   do {                            \
>>> @@ -96,7 +124,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
>>>       char buf[BUF_SIZE];
>>>       int ret = 0;
>>>   -    PRINT_ATTRf(type, p_unsigned);
>>> +    PRINT_ATTRn("type", type, p_type_id, true);
>>>       PRINT_ATTRf(size, p_unsigned);
>>>       PRINT_ATTRf(config, p_hex);
>>>       PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned, false);
>>
>> .
>>


2023-05-15 09:00:02

by Yang Jihong

[permalink] [raw]
Subject: Re: [PATCH v2 3/4] perf tools: Add printing perf_event_attr type symbol in perf_event_attr__fprintf()

Hello,

On 2023/5/12 18:34, Adrian Hunter wrote:
> On 11/05/23 10:51, Yang Jihong wrote:
>> When printing perf_event_attr, always display perf_event_attr type and its symbol
>> to improve the readability of debugging information.
>>
>> Before:
>>
>> # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>> <SNIP>
>> ------------------------------------------------------------
>> perf_event_attr:
>> size 136
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 1
>> size 136
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 2
>> size 136
>> config 0x143
>> { sample_period, sample_freq } 1
>> sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 3
>> size 136
>> config 0x10005
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 4
>> size 136
>> config 0x101
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 5
>> size 136
>> { sample_period, sample_freq } 1
>> sample_type IP|TID|TIME|CPU|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> sample_id_all 1
>> exclude_guest 1
>> bp_type 3
>> { bp_len, config2 } 0x4
>> ------------------------------------------------------------
>> <SNIP>
>>
>> After:
>>
>> # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>> <SNIP>
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 0 (PERF_TYPE_HARDWARE)
>> size 136
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 1 (PERF_TYPE_SOFTWARE)
>> size 136
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 6
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 2 (PERF_TYPE_TRACEPOINT)
>> size 136
>> config 0x143
>> { sample_period, sample_freq } 1
>> sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 7
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 3 (PERF_TYPE_HW_CACHE)
>> size 136
>> config 0x10005
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 9
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 4 (PERF_TYPE_RAW)
>> size 136
>> config 0x101
>> { sample_period, sample_freq } 4000
>> sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> freq 1
>> sample_id_all 1
>> exclude_guest 1
>> ------------------------------------------------------------
>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 10
>> ------------------------------------------------------------
>> perf_event_attr:
>> type 5 (PERF_TYPE_BREAKPOINT)
>> size 136
>> { sample_period, sample_freq } 1
>> sample_type IP|TID|TIME|CPU|IDENTIFIER
>> read_format ID
>> disabled 1
>> inherit 1
>> sample_id_all 1
>> exclude_guest 1
>> bp_type 3
>> { bp_len, config2 } 0x4
>> ------------------------------------------------------------
>> <SNIP>
>>
>> Signed-off-by: Yang Jihong <[email protected]>
>> ---
>> tools/perf/util/perf_event_attr_fprintf.c | 30 ++++++++++++++++++++++-
>> 1 file changed, 29 insertions(+), 1 deletion(-)
>>
>> diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
>> index 433029c6afc5..cd0905d8cb7a 100644
>> --- a/tools/perf/util/perf_event_attr_fprintf.c
>> +++ b/tools/perf/util/perf_event_attr_fprintf.c
>> @@ -71,6 +71,33 @@ static void __p_read_format(char *buf, size_t size, u64 value)
>> __p_bits(buf, size, value, bits);
>> }
>>
>> +#define ENUM_ID_TO_STR_CASE(x) case x: return (#x);
>> +static const char *stringify_perf_type_id(u64 value)
>> +{
>> + /* sync with enum perf_type_id in perf_event.h */
>
> Everything in this file syncs with perf_event.h, so the comment
> does not seem very useful.
OK, will fix in v3.
>
>> + switch (value) {
>> + ENUM_ID_TO_STR_CASE(PERF_TYPE_HARDWARE)
>> + ENUM_ID_TO_STR_CASE(PERF_TYPE_SOFTWARE)
>> + ENUM_ID_TO_STR_CASE(PERF_TYPE_TRACEPOINT)
>> + ENUM_ID_TO_STR_CASE(PERF_TYPE_HW_CACHE)
>> + ENUM_ID_TO_STR_CASE(PERF_TYPE_RAW)
>> + ENUM_ID_TO_STR_CASE(PERF_TYPE_BREAKPOINT)
>> + default:
>> + return NULL;
>> + }
>> +}
>> +#undef ENUM_ID_TO_STR_CASE
>> +
>> +static void __p_type_id(char *buf, size_t size, u64 value)
>> +{
>> + const char *str = stringify_perf_type_id(value);
>> +
>> + if (str == NULL)
>> + snprintf(buf, size, "%"PRIu64, value);
>> + else
>> + snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>
> These 4 lines end up getting used again about 3 times in the next
> patch, so might as well be a separate function e.g.
>
> print_id(buf, size, value, stringify_perf_type_id(value));
>
> where:
>
> static void print_id(char *buf, size_t size, u64 value, const char *str)
> {
> if (str == NULL)
> snprintf(buf, size, "%"PRIu64, value);
> else
> snprintf(buf, size, "%"PRIu64" (%s)", value, str);
> }
>
OK, will add print_id() helper in v3.
If print_id() helper is also used to print config id, is printed in the
decimal format. In the past, it is printed in the hexadecimal format,
there may be some changes here.

Before:
config 0x143

After:
config 323 (sched:sched_switch)

>> +}
>> +
>> #define BUF_SIZE 1024
>>
>> #define p_hex(val) snprintf(buf, BUF_SIZE, "%#"PRIx64, (uint64_t)(val))
>> @@ -79,6 +106,7 @@ static void __p_read_format(char *buf, size_t size, u64 value)
>> #define p_sample_type(val) __p_sample_type(buf, BUF_SIZE, val)
>> #define p_branch_sample_type(val) __p_branch_sample_type(buf, BUF_SIZE, val)
>> #define p_read_format(val) __p_read_format(buf, BUF_SIZE, val)
>> +#define p_type_id(val) __p_type_id(buf, BUF_SIZE, val)
>>
>> #define PRINT_ATTRn(_n, _f, _p, _a) \
>> do { \
>> @@ -96,7 +124,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
>> char buf[BUF_SIZE];
>> int ret = 0;
>>
>> - PRINT_ATTRf(type, p_unsigned);
>> + PRINT_ATTRn("type", type, p_type_id, true);
>> PRINT_ATTRf(size, p_unsigned);
>> PRINT_ATTRf(config, p_hex);
>> PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned, false);
>
> .
>

2023-05-15 09:54:39

by Yang Jihong

[permalink] [raw]
Subject: Re: [PATCH v2 3/4] perf tools: Add printing perf_event_attr type symbol in perf_event_attr__fprintf()

Hello,

On 2023/5/15 16:56, Adrian Hunter wrote:
> On 15/05/23 11:48, Yang Jihong wrote:
>> Hello,
>>
>> On 2023/5/12 18:34, Adrian Hunter wrote:
>>> On 11/05/23 10:51, Yang Jihong wrote:
>>>> When printing perf_event_attr, always display perf_event_attr type and its symbol
>>>> to improve the readability of debugging information.
>>>>
>>>> Before:
>>>>
>>>>    # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>>>>    <SNIP>
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             1
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 6
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             2
>>>>      size                             136
>>>>      config                           0x143
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             3
>>>>      size                             136
>>>>      config                           0x10005
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 9
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             4
>>>>      size                             136
>>>>      config                           0x101
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 10
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             5
>>>>      size                             136
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>      bp_type                          3
>>>>      { bp_len, config2 }              0x4
>>>>    ------------------------------------------------------------
>>>>    <SNIP>
>>>>
>>>> After:
>>>>
>>>>    # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>>>>    <SNIP>
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             0 (PERF_TYPE_HARDWARE)
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             1 (PERF_TYPE_SOFTWARE)
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 6
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             2 (PERF_TYPE_TRACEPOINT)
>>>>      size                             136
>>>>      config                           0x143
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             3 (PERF_TYPE_HW_CACHE)
>>>>      size                             136
>>>>      config                           0x10005
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 9
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             4 (PERF_TYPE_RAW)
>>>>      size                             136
>>>>      config                           0x101
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 10
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             5 (PERF_TYPE_BREAKPOINT)
>>>>      size                             136
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>      bp_type                          3
>>>>      { bp_len, config2 }              0x4
>>>>    ------------------------------------------------------------
>>>>    <SNIP>
>>>>
>>>> Signed-off-by: Yang Jihong <[email protected]>
>>>> ---
>>>>   tools/perf/util/perf_event_attr_fprintf.c | 30 ++++++++++++++++++++++-
>>>>   1 file changed, 29 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
>>>> index 433029c6afc5..cd0905d8cb7a 100644
>>>> --- a/tools/perf/util/perf_event_attr_fprintf.c
>>>> +++ b/tools/perf/util/perf_event_attr_fprintf.c
>>>> @@ -71,6 +71,33 @@ static void __p_read_format(char *buf, size_t size, u64 value)
>>>>       __p_bits(buf, size, value, bits);
>>>>   }
>>>>   +#define ENUM_ID_TO_STR_CASE(x) case x: return (#x);
>>>> +static const char *stringify_perf_type_id(u64 value)
>>>> +{
>>>> +    /* sync with enum perf_type_id in perf_event.h */
>>>
>>> Everything in this file syncs with perf_event.h, so the comment
>>> does not seem very useful.
>> OK, will fix in v3.
>>>
>>>> +    switch (value) {
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_HARDWARE)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_SOFTWARE)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_TRACEPOINT)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_HW_CACHE)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_RAW)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_BREAKPOINT)
>>>> +    default:
>>>> +        return NULL;
>>>> +    }
>>>> +}
>>>> +#undef ENUM_ID_TO_STR_CASE
>>>> +
>>>> +static void __p_type_id(char *buf, size_t size, u64 value)
>>>> +{
>>>> +    const char *str = stringify_perf_type_id(value);
>>>> +
>>>> +    if (str == NULL)
>>>> +        snprintf(buf, size, "%"PRIu64, value);
>>>> +    else
>>>> +        snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>>>
>>> These 4 lines end up getting used again about 3 times in the next
>>> patch, so might as well be a separate function e.g.
>>>
>>>     print_id(buf, size, value, stringify_perf_type_id(value));
>>>
>>> where:
>>>
>>> static void print_id(char *buf, size_t size, u64 value, const char *str)
>>> {
>>>     if (str == NULL)
>>>         snprintf(buf, size, "%"PRIu64, value);
>>>     else
>>>         snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>>> }
>>>
>> OK, will add print_id() helper in v3.
>> If print_id() helper is also used to print config id, is printed in the decimal format. In the past, it is printed in the hexadecimal format,
>> there may be some changes here.
>>
>> Before:
>>   config                           0x143
>>
>> After:
>>   config                           323 (sched:sched_switch)
>
> Right I didn't notice the difference. Best keep print_id() just for the hex cases.
>
Emm...,Is the type id also printed in hexadecimal format?

static void print_id(char *buf, size_t size, u64 value, const char *str)
{
if (str == NULL)
snprintf(buf, size, "%#"PRIx64, value);
else
snprintf(buf, size, "%#"PRIx64" (%s)", value, str);
}

Output:
perf_event_attr:
type 0x2 (PERF_TYPE_TRACEPOINT)
size 136
config 0x124 (sched:sched_switch)

Because v3 has just been sent out, if need to modify it according to
this, I'll send v4.


Thanks,
Yang

2023-05-16 07:11:57

by Yang Jihong

[permalink] [raw]
Subject: Re: [PATCH v2 3/4] perf tools: Add printing perf_event_attr type symbol in perf_event_attr__fprintf()

Hello,

On 2023/5/15 16:56, Adrian Hunter wrote:
> On 15/05/23 11:48, Yang Jihong wrote:
>> Hello,
>>
>> On 2023/5/12 18:34, Adrian Hunter wrote:
>>> On 11/05/23 10:51, Yang Jihong wrote:
>>>> When printing perf_event_attr, always display perf_event_attr type and its symbol
>>>> to improve the readability of debugging information.
>>>>
>>>> Before:
>>>>
>>>>    # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>>>>    <SNIP>
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             1
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 6
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             2
>>>>      size                             136
>>>>      config                           0x143
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             3
>>>>      size                             136
>>>>      config                           0x10005
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 9
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             4
>>>>      size                             136
>>>>      config                           0x101
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 10
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             5
>>>>      size                             136
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>      bp_type                          3
>>>>      { bp_len, config2 }              0x4
>>>>    ------------------------------------------------------------
>>>>    <SNIP>
>>>>
>>>> After:
>>>>
>>>>    # perf --debug verbose=2 record -e cycles,cpu-clock,sched:sched_switch,branch-load-misses,r101,mem:0x0 -C 0 true
>>>>    <SNIP>
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             0 (PERF_TYPE_HARDWARE)
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             1 (PERF_TYPE_SOFTWARE)
>>>>      size                             136
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 6
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             2 (PERF_TYPE_TRACEPOINT)
>>>>      size                             136
>>>>      config                           0x143
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             3 (PERF_TYPE_HW_CACHE)
>>>>      size                             136
>>>>      config                           0x10005
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 9
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             4 (PERF_TYPE_RAW)
>>>>      size                             136
>>>>      config                           0x101
>>>>      { sample_period, sample_freq }   4000
>>>>      sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      freq                             1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>    ------------------------------------------------------------
>>>>    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 10
>>>>    ------------------------------------------------------------
>>>>    perf_event_attr:
>>>>      type                             5 (PERF_TYPE_BREAKPOINT)
>>>>      size                             136
>>>>      { sample_period, sample_freq }   1
>>>>      sample_type                      IP|TID|TIME|CPU|IDENTIFIER
>>>>      read_format                      ID
>>>>      disabled                         1
>>>>      inherit                          1
>>>>      sample_id_all                    1
>>>>      exclude_guest                    1
>>>>      bp_type                          3
>>>>      { bp_len, config2 }              0x4
>>>>    ------------------------------------------------------------
>>>>    <SNIP>
>>>>
>>>> Signed-off-by: Yang Jihong <[email protected]>
>>>> ---
>>>>   tools/perf/util/perf_event_attr_fprintf.c | 30 ++++++++++++++++++++++-
>>>>   1 file changed, 29 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
>>>> index 433029c6afc5..cd0905d8cb7a 100644
>>>> --- a/tools/perf/util/perf_event_attr_fprintf.c
>>>> +++ b/tools/perf/util/perf_event_attr_fprintf.c
>>>> @@ -71,6 +71,33 @@ static void __p_read_format(char *buf, size_t size, u64 value)
>>>>       __p_bits(buf, size, value, bits);
>>>>   }
>>>>   +#define ENUM_ID_TO_STR_CASE(x) case x: return (#x);
>>>> +static const char *stringify_perf_type_id(u64 value)
>>>> +{
>>>> +    /* sync with enum perf_type_id in perf_event.h */
>>>
>>> Everything in this file syncs with perf_event.h, so the comment
>>> does not seem very useful.
>> OK, will fix in v3.
>>>
>>>> +    switch (value) {
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_HARDWARE)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_SOFTWARE)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_TRACEPOINT)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_HW_CACHE)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_RAW)
>>>> +    ENUM_ID_TO_STR_CASE(PERF_TYPE_BREAKPOINT)
>>>> +    default:
>>>> +        return NULL;
>>>> +    }
>>>> +}
>>>> +#undef ENUM_ID_TO_STR_CASE
>>>> +
>>>> +static void __p_type_id(char *buf, size_t size, u64 value)
>>>> +{
>>>> +    const char *str = stringify_perf_type_id(value);
>>>> +
>>>> +    if (str == NULL)
>>>> +        snprintf(buf, size, "%"PRIu64, value);
>>>> +    else
>>>> +        snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>>>
>>> These 4 lines end up getting used again about 3 times in the next
>>> patch, so might as well be a separate function e.g.
>>>
>>>     print_id(buf, size, value, stringify_perf_type_id(value));
>>>
>>> where:
>>>
>>> static void print_id(char *buf, size_t size, u64 value, const char *str)
>>> {
>>>     if (str == NULL)
>>>         snprintf(buf, size, "%"PRIu64, value);
>>>     else
>>>         snprintf(buf, size, "%"PRIu64" (%s)", value, str);
>>> }
>>>
>> OK, will add print_id() helper in v3.
>> If print_id() helper is also used to print config id, is printed in the decimal format. In the past, it is printed in the hexadecimal format,
>> there may be some changes here.
>>
>> Before:
>>   config                           0x143
>>
>> After:
>>   config                           323 (sched:sched_switch)
>
> Right I didn't notice the difference. Best keep print_id() just for the hex cases.
>
v4 has been sent, print_id() helper is changed to a macro function to
support printing of both 'hex' and 'unsigned' formats.
Please see if it's OK.

Thanks,
Yang