diff mbox series

[v7,09/25] trace-cmd library: Move CPU flyrecord trace metadata into the buffer option, for trace file version 7

Message ID 20211210105448.97850-10-tz.stoyanov@gmail.com (mailing list archive)
State Superseded
Headers show
Series Trace file version 7 - sections | expand

Commit Message

Tzvetomir Stoyanov (VMware) Dec. 10, 2021, 10:54 a.m. UTC
Extended the BUFFER trace option in trace file version 7 with CPU
flyrecord trace metadata. In the version 6 of the trace file, this metadata
is located at several places in the file. Part of the metadata is only for
the top trace instance, thus limiting per-instance configuration. Moving
all CPU trace related metadata in the BUFFER option simplifies the parsing
and makes per-instance configuration more flexible. In the new file
structure, the top instance is treated as any other instances.
The format of the extended BUFFER option is:
 - offset of the buffer in the trace file
 - name of the buffer
 - trace clock, used in this buffer for events timestamps
 - count of CPUs with trace data
 - array, describing each CPU with trace data:
   - CPU id
   - offset of CPU trace data in the trace file
   - size of the recorded CPU trace data

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
 lib/trace-cmd/trace-output.c | 191 +++++++++++++++++++++++++----------
 1 file changed, 137 insertions(+), 54 deletions(-)

Comments

Steven Rostedt Jan. 15, 2022, 3:12 p.m. UTC | #1
On Fri, 10 Dec 2021 12:54:32 +0200
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:

I'm going to keep mentioning spacing ;-)

> Extended the BUFFER trace option in trace file version 7 with CPU
> flyrecord trace metadata. In the version 6 of the trace file, this metadata
> is located at several places in the file. Part of the metadata is only for
> the top trace instance, thus limiting per-instance configuration. Moving
> all CPU trace related metadata in the BUFFER option simplifies the parsing
> and makes per-instance configuration more flexible. In the new file
> structure, the top instance is treated as any other instances.

space

> The format of the extended BUFFER option is:
>  - offset of the buffer in the trace file
>  - name of the buffer
>  - trace clock, used in this buffer for events timestamps
>  - count of CPUs with trace data
>  - array, describing each CPU with trace data:
>    - CPU id
>    - offset of CPU trace data in the trace file
>    - size of the recorded CPU trace data
> 
> Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
> ---
>  lib/trace-cmd/trace-output.c | 191 +++++++++++++++++++++++++----------
>  1 file changed, 137 insertions(+), 54 deletions(-)
> 
> diff --git a/lib/trace-cmd/trace-output.c b/lib/trace-cmd/trace-output.c
> index 59093be2..6e40c929 100644
> --- a/lib/trace-cmd/trace-output.c
> +++ b/lib/trace-cmd/trace-output.c
> @@ -1675,7 +1675,7 @@ int tracecmd_append_options(struct tracecmd_output *handle)
>  }
>  
>  static struct tracecmd_option *
> -add_buffer_option(struct tracecmd_output *handle, const char *name, int cpus)
> +add_buffer_option_v6(struct tracecmd_output *handle, const char *name, int cpus)
>  {
>  	struct tracecmd_option *option;
>  	char *buf;
> @@ -1725,8 +1725,11 @@ int tracecmd_write_buffer_info(struct tracecmd_output *handle)
>  	struct tracecmd_option *option;
>  	struct tracecmd_buffer *buf;
>  
> +	if (HAS_SECTIONS(handle))
> +		return 0;
> +
>  	list_for_each_entry(buf, &handle->buffers, list) {
> -		option = add_buffer_option(handle, buf->name, buf->cpus);
> +		option = add_buffer_option_v6(handle, buf->name, buf->cpus);
>  		if (!option)
>  			return -1;
>  		buf->option = option;
> @@ -1777,6 +1780,98 @@ int tracecmd_write_cmdlines(struct tracecmd_output *handle)
>  	return 0;
>  }
>  
> +static char *get_clock(struct tracecmd_output *handle)
> +{
> +	struct tracefs_instance *inst;
> +
> +	if (handle->trace_clock)
> +		return handle->trace_clock;
> +
> +	/*
> +	 * If no clock is set on this handle, get the trace clock of
> +	 * the top instance in the handle's tracing dir
> +	 */
> +	inst = tracefs_instance_alloc(handle->tracing_dir, NULL);
> +	if (!inst)
> +		return NULL;
> +	handle->trace_clock = tracefs_get_clock(inst);

Why allocate an instance, doesn't:

	tracefs_get_clock(NULL);

do the same? (at least the man page says it does).

Or are you worried that this has to do something with the tracing_dir?
But do we care?

> +	tracefs_instance_free(inst);
> +	return handle->trace_clock;
> +}
> +
> +__hidden struct tracecmd_option *
> +out_add_buffer_option_v7(struct tracecmd_output *handle, const char *name,

Again, I think it's safe to remove all the references to v7, and just
have that be the default.

> +			 unsigned short id, unsigned long long data_offset,
> +			 int cpus, struct data_file_write *cpu_data)
> +{
> +	struct tracecmd_option *option;
> +	int i, j = 0, k = 0;
> +	int *cpu_ids = NULL;
> +	struct iovec *vect;
> +	char *clock;
> +
> +	if (!HAS_SECTIONS(handle))
> +		return NULL;
> +
> +	clock = get_clock(handle);
> +
> +	/* Buffer flyrecord option, v7:

Including here (no need to say "v7")

> +	 *  - trace data offset in the file
> +	 *  - buffer name
> +	 *  - buffer clock
> +	 *  - CPU count
> +	 *  - for each CPU:
> +	 *    - CPU id
> +	 *    - CPU trace data offset in the file
> +	 *    - CPU trace data size
> +	 */
> +
> +	/* Buffer latency option, v7:

and here.

> +	 *  - trace data offset in the file
> +	 *  - buffer name
> +	 *  - buffer clock
> +	 */
> +
> +	vect = calloc(5 + (cpus * 3), sizeof(struct iovec));

What's with the magical 5 and 3 numbers above?

As from the comments above, I only count 4 and 3.

 4 : offset, name, clock, count
 3 : cpu offset, name, clock

Could include the above in a comment too.

-- Steve

> +	if (!vect)
> +		return NULL;
> +	if (cpus) {
> +		cpu_ids = calloc(cpus, sizeof(int));
> +		if (!cpu_ids) {
> +			free(vect);
> +			return NULL;
> +		}
> +	}
> +	vect[j].iov_base = (void *) &data_offset;
> +	vect[j++].iov_len = 8;
> +	vect[j].iov_base = (void *) name;
> +	vect[j++].iov_len = strlen(name) + 1;
> +	vect[j].iov_base = (void *) clock;
> +	vect[j++].iov_len = strlen(clock) + 1;
> +	if (id == TRACECMD_OPTION_BUFFER) {
> +		vect[j].iov_base = (void *) &k;
> +		vect[j++].iov_len = 4;
> +		for (i = 0; i < cpus; i++) {
> +			if (!cpu_data[i].file_size)
> +				continue;
> +			cpu_ids[i] = i;
> +			vect[j].iov_base = &cpu_ids[i];
> +			vect[j++].iov_len = 4;
> +			vect[j].iov_base = &cpu_data[i].data_offset;
> +			vect[j++].iov_len = 8;
> +			vect[j].iov_base = &cpu_data[i].write_size;
> +			vect[j++].iov_len = 8;
> +			k++;
> +		}
> +	}
> +
> +	option = tracecmd_add_option_v(handle, id, vect, j);
> +	free(vect);
> +	free(cpu_ids);
> +
> +	return option;
> +}
> +
>  struct tracecmd_output *tracecmd_create_file_latency(const char *output_file, int cpus)
>  {
>  	struct tracecmd_output *handle;
> @@ -1847,8 +1942,8 @@ out:
>  	return ret;
>  }
Tzvetomir Stoyanov (VMware) Jan. 17, 2022, 1:43 p.m. UTC | #2
On Sat, Jan 15, 2022 at 5:12 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Fri, 10 Dec 2021 12:54:32 +0200
> "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:
>
> I'm going to keep mentioning spacing ;-)
>
> > Extended the BUFFER trace option in trace file version 7 with CPU
> > flyrecord trace metadata. In the version 6 of the trace file, this metadata
> > is located at several places in the file. Part of the metadata is only for
> > the top trace instance, thus limiting per-instance configuration. Moving
> > all CPU trace related metadata in the BUFFER option simplifies the parsing
> > and makes per-instance configuration more flexible. In the new file
> > structure, the top instance is treated as any other instances.
>
> space
>
> > The format of the extended BUFFER option is:
> >  - offset of the buffer in the trace file
> >  - name of the buffer
> >  - trace clock, used in this buffer for events timestamps
> >  - count of CPUs with trace data
> >  - array, describing each CPU with trace data:
> >    - CPU id
> >    - offset of CPU trace data in the trace file
> >    - size of the recorded CPU trace data
> >
> > Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
> > ---
> >  lib/trace-cmd/trace-output.c | 191 +++++++++++++++++++++++++----------
> >  1 file changed, 137 insertions(+), 54 deletions(-)
> >
> > diff --git a/lib/trace-cmd/trace-output.c b/lib/trace-cmd/trace-output.c
> > index 59093be2..6e40c929 100644
> > --- a/lib/trace-cmd/trace-output.c
> > +++ b/lib/trace-cmd/trace-output.c
> > @@ -1675,7 +1675,7 @@ int tracecmd_append_options(struct tracecmd_output *handle)
> >  }
> >
> >  static struct tracecmd_option *
> > -add_buffer_option(struct tracecmd_output *handle, const char *name, int cpus)
> > +add_buffer_option_v6(struct tracecmd_output *handle, const char *name, int cpus)
> >  {
> >       struct tracecmd_option *option;
> >       char *buf;
> > @@ -1725,8 +1725,11 @@ int tracecmd_write_buffer_info(struct tracecmd_output *handle)
> >       struct tracecmd_option *option;
> >       struct tracecmd_buffer *buf;
> >
> > +     if (HAS_SECTIONS(handle))
> > +             return 0;
> > +
> >       list_for_each_entry(buf, &handle->buffers, list) {
> > -             option = add_buffer_option(handle, buf->name, buf->cpus);
> > +             option = add_buffer_option_v6(handle, buf->name, buf->cpus);
> >               if (!option)
> >                       return -1;
> >               buf->option = option;
> > @@ -1777,6 +1780,98 @@ int tracecmd_write_cmdlines(struct tracecmd_output *handle)
> >       return 0;
> >  }
> >
> > +static char *get_clock(struct tracecmd_output *handle)
> > +{
> > +     struct tracefs_instance *inst;
> > +
> > +     if (handle->trace_clock)
> > +             return handle->trace_clock;
> > +
> > +     /*
> > +      * If no clock is set on this handle, get the trace clock of
> > +      * the top instance in the handle's tracing dir
> > +      */
> > +     inst = tracefs_instance_alloc(handle->tracing_dir, NULL);
> > +     if (!inst)
> > +             return NULL;
> > +     handle->trace_clock = tracefs_get_clock(inst);
>
> Why allocate an instance, doesn't:
>
>         tracefs_get_clock(NULL);
>
> do the same? (at least the man page says it does).
>
> Or are you worried that this has to do something with the tracing_dir?
> But do we care?

Yes, because of tracing_dir. I'll add a check:

if (!handle->tracing_dir) {
      handle->trace_clock = tracefs_get_clock(NULL);
      return handle->trace_clock;
}

which is the most common case. If there is tracing_dir associated with
the handle, the old logic should be used - just to be on the safe
side.

>
> > +     tracefs_instance_free(inst);
> > +     return handle->trace_clock;
> > +}
> > +
> > +__hidden struct tracecmd_option *
> > +out_add_buffer_option_v7(struct tracecmd_output *handle, const char *name,
>
> Again, I think it's safe to remove all the references to v7, and just
> have that be the default.
>
> > +                      unsigned short id, unsigned long long data_offset,
> > +                      int cpus, struct data_file_write *cpu_data)
> > +{
> > +     struct tracecmd_option *option;
> > +     int i, j = 0, k = 0;
> > +     int *cpu_ids = NULL;
> > +     struct iovec *vect;
> > +     char *clock;
> > +
> > +     if (!HAS_SECTIONS(handle))
> > +             return NULL;
> > +
> > +     clock = get_clock(handle);
> > +
> > +     /* Buffer flyrecord option, v7:
>
> Including here (no need to say "v7")
>
> > +      *  - trace data offset in the file
> > +      *  - buffer name
> > +      *  - buffer clock
> > +      *  - CPU count
> > +      *  - for each CPU:
> > +      *    - CPU id
> > +      *    - CPU trace data offset in the file
> > +      *    - CPU trace data size
> > +      */
> > +
> > +     /* Buffer latency option, v7:
>
> and here.
>
> > +      *  - trace data offset in the file
> > +      *  - buffer name
> > +      *  - buffer clock
> > +      */
> > +
> > +     vect = calloc(5 + (cpus * 3), sizeof(struct iovec));
>
> What's with the magical 5 and 3 numbers above?
>
> As from the comments above, I only count 4 and 3.
>
>  4 : offset, name, clock, count
>  3 : cpu offset, name, clock
>
> Could include the above in a comment too.
>
> -- Steve
>
> > +     if (!vect)
> > +             return NULL;
> > +     if (cpus) {
> > +             cpu_ids = calloc(cpus, sizeof(int));
> > +             if (!cpu_ids) {
> > +                     free(vect);
> > +                     return NULL;
> > +             }
> > +     }
> > +     vect[j].iov_base = (void *) &data_offset;
> > +     vect[j++].iov_len = 8;
> > +     vect[j].iov_base = (void *) name;
> > +     vect[j++].iov_len = strlen(name) + 1;
> > +     vect[j].iov_base = (void *) clock;
> > +     vect[j++].iov_len = strlen(clock) + 1;
> > +     if (id == TRACECMD_OPTION_BUFFER) {
> > +             vect[j].iov_base = (void *) &k;
> > +             vect[j++].iov_len = 4;
> > +             for (i = 0; i < cpus; i++) {
> > +                     if (!cpu_data[i].file_size)
> > +                             continue;
> > +                     cpu_ids[i] = i;
> > +                     vect[j].iov_base = &cpu_ids[i];
> > +                     vect[j++].iov_len = 4;
> > +                     vect[j].iov_base = &cpu_data[i].data_offset;
> > +                     vect[j++].iov_len = 8;
> > +                     vect[j].iov_base = &cpu_data[i].write_size;
> > +                     vect[j++].iov_len = 8;
> > +                     k++;
> > +             }
> > +     }
> > +
> > +     option = tracecmd_add_option_v(handle, id, vect, j);
> > +     free(vect);
> > +     free(cpu_ids);
> > +
> > +     return option;
> > +}
> > +
> >  struct tracecmd_output *tracecmd_create_file_latency(const char *output_file, int cpus)
> >  {
> >       struct tracecmd_output *handle;
> > @@ -1847,8 +1942,8 @@ out:
> >       return ret;
> >  }
diff mbox series

Patch

diff --git a/lib/trace-cmd/trace-output.c b/lib/trace-cmd/trace-output.c
index 59093be2..6e40c929 100644
--- a/lib/trace-cmd/trace-output.c
+++ b/lib/trace-cmd/trace-output.c
@@ -1675,7 +1675,7 @@  int tracecmd_append_options(struct tracecmd_output *handle)
 }
 
 static struct tracecmd_option *
-add_buffer_option(struct tracecmd_output *handle, const char *name, int cpus)
+add_buffer_option_v6(struct tracecmd_output *handle, const char *name, int cpus)
 {
 	struct tracecmd_option *option;
 	char *buf;
@@ -1725,8 +1725,11 @@  int tracecmd_write_buffer_info(struct tracecmd_output *handle)
 	struct tracecmd_option *option;
 	struct tracecmd_buffer *buf;
 
+	if (HAS_SECTIONS(handle))
+		return 0;
+
 	list_for_each_entry(buf, &handle->buffers, list) {
-		option = add_buffer_option(handle, buf->name, buf->cpus);
+		option = add_buffer_option_v6(handle, buf->name, buf->cpus);
 		if (!option)
 			return -1;
 		buf->option = option;
@@ -1777,6 +1780,98 @@  int tracecmd_write_cmdlines(struct tracecmd_output *handle)
 	return 0;
 }
 
+static char *get_clock(struct tracecmd_output *handle)
+{
+	struct tracefs_instance *inst;
+
+	if (handle->trace_clock)
+		return handle->trace_clock;
+
+	/*
+	 * If no clock is set on this handle, get the trace clock of
+	 * the top instance in the handle's tracing dir
+	 */
+	inst = tracefs_instance_alloc(handle->tracing_dir, NULL);
+	if (!inst)
+		return NULL;
+	handle->trace_clock = tracefs_get_clock(inst);
+	tracefs_instance_free(inst);
+	return handle->trace_clock;
+}
+
+__hidden struct tracecmd_option *
+out_add_buffer_option_v7(struct tracecmd_output *handle, const char *name,
+			 unsigned short id, unsigned long long data_offset,
+			 int cpus, struct data_file_write *cpu_data)
+{
+	struct tracecmd_option *option;
+	int i, j = 0, k = 0;
+	int *cpu_ids = NULL;
+	struct iovec *vect;
+	char *clock;
+
+	if (!HAS_SECTIONS(handle))
+		return NULL;
+
+	clock = get_clock(handle);
+
+	/* Buffer flyrecord option, v7:
+	 *  - trace data offset in the file
+	 *  - buffer name
+	 *  - buffer clock
+	 *  - CPU count
+	 *  - for each CPU:
+	 *    - CPU id
+	 *    - CPU trace data offset in the file
+	 *    - CPU trace data size
+	 */
+
+	/* Buffer latency option, v7:
+	 *  - trace data offset in the file
+	 *  - buffer name
+	 *  - buffer clock
+	 */
+
+	vect = calloc(5 + (cpus * 3), sizeof(struct iovec));
+	if (!vect)
+		return NULL;
+	if (cpus) {
+		cpu_ids = calloc(cpus, sizeof(int));
+		if (!cpu_ids) {
+			free(vect);
+			return NULL;
+		}
+	}
+	vect[j].iov_base = (void *) &data_offset;
+	vect[j++].iov_len = 8;
+	vect[j].iov_base = (void *) name;
+	vect[j++].iov_len = strlen(name) + 1;
+	vect[j].iov_base = (void *) clock;
+	vect[j++].iov_len = strlen(clock) + 1;
+	if (id == TRACECMD_OPTION_BUFFER) {
+		vect[j].iov_base = (void *) &k;
+		vect[j++].iov_len = 4;
+		for (i = 0; i < cpus; i++) {
+			if (!cpu_data[i].file_size)
+				continue;
+			cpu_ids[i] = i;
+			vect[j].iov_base = &cpu_ids[i];
+			vect[j++].iov_len = 4;
+			vect[j].iov_base = &cpu_data[i].data_offset;
+			vect[j++].iov_len = 8;
+			vect[j].iov_base = &cpu_data[i].write_size;
+			vect[j++].iov_len = 8;
+			k++;
+		}
+	}
+
+	option = tracecmd_add_option_v(handle, id, vect, j);
+	free(vect);
+	free(cpu_ids);
+
+	return option;
+}
+
 struct tracecmd_output *tracecmd_create_file_latency(const char *output_file, int cpus)
 {
 	struct tracecmd_output *handle;
@@ -1847,8 +1942,8 @@  out:
 	return ret;
 }
 
-static int update_buffer_cpu_offset(struct tracecmd_output *handle,
-				    const char *name, tsize_t offset)
+static int update_buffer_cpu_offset_v6(struct tracecmd_output *handle,
+				       const char *name, tsize_t offset)
 {
 	tsize_t b_offset;
 	tsize_t current;
@@ -1881,26 +1976,6 @@  static int update_buffer_cpu_offset(struct tracecmd_output *handle,
 	return 0;
 }
 
-
-static char *get_clock(struct tracecmd_output *handle)
-{
-	struct tracefs_instance *inst;
-
-	if (handle->trace_clock)
-		return handle->trace_clock;
-
-	/*
-	 * If no clock is set on this handle, get the trace clock of
-	 * the top instance in the handle's tracing dir
-	 */
-	inst = tracefs_instance_alloc(handle->tracing_dir, NULL);
-	if (!inst)
-		return NULL;
-	handle->trace_clock = tracefs_get_clock(inst);
-	tracefs_instance_free(inst);
-	return handle->trace_clock;
-}
-
 __hidden int out_write_cpu_data(struct tracecmd_output *handle,
 				int cpus, struct cpu_data_source *data, const char *buff_name)
 {
@@ -1924,7 +1999,7 @@  __hidden int out_write_cpu_data(struct tracecmd_output *handle,
 	}
 
 	data_offs = do_lseek(handle, 0, SEEK_CUR);
-	if (do_write_check(handle, "flyrecord", 10))
+	if (!HAS_SECTIONS(handle) && do_write_check(handle, "flyrecord", 10))
 		goto out_free;
 
 	data_files = calloc(cpus, sizeof(*data_files));
@@ -1937,19 +2012,23 @@  __hidden int out_write_cpu_data(struct tracecmd_output *handle,
 		 * Place 0 for the data offset and size, and save the offsets to
 		 * updated them with the correct data later.
 		 */
-		endian8 = 0;
-		data_files[i].file_data_offset = do_lseek(handle, 0, SEEK_CUR);
-		if (do_write_check(handle, &endian8, 8))
-			goto out_free;
-		data_files[i].file_write_size = do_lseek(handle, 0, SEEK_CUR);
-		if (do_write_check(handle, &endian8, 8))
-			goto out_free;
+		if (!HAS_SECTIONS(handle)) {
+			endian8 = 0;
+			data_files[i].file_data_offset = do_lseek(handle, 0, SEEK_CUR);
+			if (do_write_check(handle, &endian8, 8))
+				goto out_free;
+			data_files[i].file_write_size = do_lseek(handle, 0, SEEK_CUR);
+			if (do_write_check(handle, &endian8, 8))
+				goto out_free;
+		}
 	}
 
-	update_buffer_cpu_offset(handle, buff_name, data_offs);
-	clock = get_clock(handle);
-	if (clock && save_clock(handle, clock))
-		goto out_free;
+	if (!HAS_SECTIONS(handle)) {
+		update_buffer_cpu_offset_v6(handle, buff_name, data_offs);
+		clock = get_clock(handle);
+		if (clock && save_clock(handle, clock))
+			goto out_free;
+	}
 
 	for (i = 0; i < cpus; i++) {
 		data_files[i].data_offset = do_lseek(handle, 0, SEEK_CUR);
@@ -1980,29 +2059,33 @@  __hidden int out_write_cpu_data(struct tracecmd_output *handle,
 			data_files[i].write_size = 0;
 		}
 
-		/* Write the real CPU data offset in the file */
-		if (do_lseek(handle, data_files[i].file_data_offset, SEEK_SET) == (off64_t)-1)
-			goto out_free;
-		endian8 = convert_endian_8(handle, data_files[i].data_offset);
-		if (do_write_check(handle, &endian8, 8))
-			goto out_free;
-
-		/* Write the real CPU data size in the file */
-		if (do_lseek(handle, data_files[i].file_write_size, SEEK_SET) == (off64_t)-1)
-			goto out_free;
-		endian8 = convert_endian_8(handle, data_files[i].write_size);
-		if (do_write_check(handle, &endian8, 8))
-			goto out_free;
-
-		offset = data_files[i].data_offset + data_files[i].write_size;
-		if (do_lseek(handle, offset, SEEK_SET) == (off64_t)-1)
-			goto out_free;
-
+		if (!HAS_SECTIONS(handle)) {
+			/* Write the real CPU data offset in the file */
+			if (do_lseek(handle, data_files[i].file_data_offset, SEEK_SET) == (off64_t)-1)
+				goto out_free;
+			endian8 = convert_endian_8(handle, data_files[i].data_offset);
+			if (do_write_check(handle, &endian8, 8))
+				goto out_free;
+			/* Write the real CPU data size in the file */
+			if (do_lseek(handle, data_files[i].file_write_size, SEEK_SET) == (off64_t)-1)
+				goto out_free;
+			endian8 = convert_endian_8(handle, data_files[i].write_size);
+			if (do_write_check(handle, &endian8, 8))
+				goto out_free;
+			offset = data_files[i].data_offset + data_files[i].write_size;
+			if (do_lseek(handle, offset, SEEK_SET) == (off64_t)-1)
+				goto out_free;
+		}
 		if (!tracecmd_get_quiet(handle))
 			fprintf(stderr, "    %llu bytes in size\n",
 				(unsigned long long)data_files[i].write_size);
 	}
 
+	if (HAS_SECTIONS(handle) &&
+	    !out_add_buffer_option_v7(handle, buff_name,
+				      TRACECMD_OPTION_BUFFER, data_offs, cpus, data_files))
+		goto out_free;
+
 	free(data_files);
 	if (do_lseek(handle, 0, SEEK_END) == (off64_t)-1)
 		return -1;