Commit cd772904 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Steven Rostedt (VMware)
Browse files

libtraceevent: Add __rel_loc relative location attribute support 

Add '__rel_loc' new dynamic data location attribute which encodes
the data location from the next to the field itself. This is similar
to the '__data_loc' but the location offset is not from the event
entry but from the next of the field.

This patch adds '__rel_loc' decoding support in the libtraceevent.

Link: https://lkml.kernel.org/r/163757343994.510314.13241077597729303802.stgit@devnote2



Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent b466b133

tools/lib/traceevent/event-parse.c

+40 −19
Original line number Diff line number Diff line
@@ -1367,6 +1367,14 @@ static int field_is_dynamic(struct tep_format_field *field) 
	return 0;

}



static int field_is_relative_dynamic(struct tep_format_field *field)

{

	if (strncmp(field->type, "__rel_loc", 9) == 0)

		return 1;



	return 0;

}



static int field_is_long(struct tep_format_field *field)

{

	/* includes long long */
@@ -1622,6 +1630,8 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field ** 
			field->flags |= TEP_FIELD_IS_STRING;

		if (field_is_dynamic(field))

			field->flags |= TEP_FIELD_IS_DYNAMIC;

		if (field_is_relative_dynamic(field))

			field->flags |= TEP_FIELD_IS_DYNAMIC | TEP_FIELD_IS_RELATIVE;

		if (field_is_long(field))

			field->flags |= TEP_FIELD_IS_LONG;
@@ -2928,7 +2938,7 @@ process_str(struct tep_event *event __maybe_unused, struct tep_print_arg *arg, 


	arg->type = TEP_PRINT_STRING;

	arg->string.string = token;

	arg->string.offset = -1;

	arg->string.field = NULL;



	if (read_expected(TEP_EVENT_DELIM, ")") < 0)

		goto out_err;
@@ -2957,7 +2967,7 @@ process_bitmask(struct tep_event *event __maybe_unused, struct tep_print_arg *ar 


	arg->type = TEP_PRINT_BITMASK;

	arg->bitmask.bitmask = token;

	arg->bitmask.offset = -1;

	arg->bitmask.field = NULL;



	if (read_expected(TEP_EVENT_DELIM, ")") < 0)

		goto out_err;
@@ -3123,19 +3133,23 @@ process_function(struct tep_event *event, struct tep_print_arg *arg, 
		free_token(token);

		return process_int_array(event, arg, tok);

	}

	if (strcmp(token, "__get_str") == 0) {

	if (strcmp(token, "__get_str") == 0 ||

	    strcmp(token, "__get_rel_str") == 0) {

		free_token(token);

		return process_str(event, arg, tok);

	}

	if (strcmp(token, "__get_bitmask") == 0) {

	if (strcmp(token, "__get_bitmask") == 0 ||

	    strcmp(token, "__get_rel_bitmask") == 0) {

		free_token(token);

		return process_bitmask(event, arg, tok);

	}

	if (strcmp(token, "__get_dynamic_array") == 0) {

	if (strcmp(token, "__get_dynamic_array") == 0 ||

	    strcmp(token, "__get_rel_dynamic_array") == 0) {

		free_token(token);

		return process_dynamic_array(event, arg, tok);

	}

	if (strcmp(token, "__get_dynamic_array_len") == 0) {

	if (strcmp(token, "__get_dynamic_array_len") == 0 ||

	    strcmp(token, "__get_rel_dynamic_array_len") == 0) {

		free_token(token);

		return process_dynamic_array_len(event, arg, tok);

	}
@@ -4163,14 +4177,16 @@ static void print_str_arg(struct trace_seq *s, void *data, int size, 
	case TEP_PRINT_STRING: {

		int str_offset;



		if (arg->string.offset == -1) {

			struct tep_format_field *f;

		if (!arg->string.field)

			arg->string.field = tep_find_any_field(event, arg->string.string);

		if (!arg->string.field)

			break;



			f = tep_find_any_field(event, arg->string.string);

			arg->string.offset = f->offset;

		}

		str_offset = data2host4(tep, *(unsigned int *)(data + arg->string.offset));

		str_offset = data2host4(tep,

				*(unsigned int *)(data + arg->string.field->offset));

		str_offset &= 0xffff;

		if (arg->string.field->flags & TEP_FIELD_IS_RELATIVE)

			str_offset += arg->string.field->offset + arg->string.field->size;

		print_str_to_seq(s, format, len_arg, ((char *)data) + str_offset);

		break;

	}
@@ -4181,15 +4197,16 @@ static void print_str_arg(struct trace_seq *s, void *data, int size, 
		int bitmask_offset;

		int bitmask_size;



		if (arg->bitmask.offset == -1) {

			struct tep_format_field *f;



			f = tep_find_any_field(event, arg->bitmask.bitmask);

			arg->bitmask.offset = f->offset;

		}

		bitmask_offset = data2host4(tep, *(unsigned int *)(data + arg->bitmask.offset));

		if (!arg->bitmask.field)

			arg->bitmask.field = tep_find_any_field(event, arg->bitmask.bitmask);

		if (!arg->bitmask.field)

			break;

		bitmask_offset = data2host4(tep,

				*(unsigned int *)(data + arg->bitmask.field->offset));

		bitmask_size = bitmask_offset >> 16;

		bitmask_offset &= 0xffff;

		if (arg->bitmask.field->flags & TEP_FIELD_IS_RELATIVE)

			bitmask_offset += arg->bitmask.field->offset + arg->bitmask.field->size;

		print_bitmask_to_seq(tep, s, format, len_arg,

				     data + bitmask_offset, bitmask_size);

		break;
@@ -5109,6 +5126,8 @@ void tep_print_field(struct trace_seq *s, void *data, 
			offset = val;

			len = offset >> 16;

			offset &= 0xffff;

			if (field->flags & TEP_FIELD_IS_RELATIVE)

				offset += field->offset + field->size;

		}

		if (field->flags & TEP_FIELD_IS_STRING &&

		    is_printable_array(data + offset, len)) {
@@ -6987,6 +7006,8 @@ void *tep_get_field_raw(struct trace_seq *s, struct tep_event *event, 
					 data + offset, field->size);

		*len = offset >> 16;

		offset &= 0xffff;

		if (field->flags & TEP_FIELD_IS_RELATIVE)

			offset += field->offset + field->size;

	} else

		*len = field->size;

tools/lib/traceevent/event-parse.h

+3 −2
Original line number Diff line number Diff line
@@ -125,6 +125,7 @@ enum tep_format_flags { 
	TEP_FIELD_IS_LONG	= 32,

	TEP_FIELD_IS_FLAG	= 64,

	TEP_FIELD_IS_SYMBOLIC	= 128,

	TEP_FIELD_IS_RELATIVE	= 256,

};



struct tep_format_field {
@@ -153,12 +154,12 @@ struct tep_print_arg_atom { 


struct tep_print_arg_string {

	char			*string;

	int			offset;

	struct tep_format_field *field;

};



struct tep_print_arg_bitmask {

	char			*bitmask;

	int			offset;

	struct tep_format_field *field;

};



struct tep_print_arg_field {

tools/lib/traceevent/parse-filter.c

+4 −1
Original line number Diff line number Diff line
@@ -1712,8 +1712,11 @@ static const char *get_field_str(struct tep_filter_arg *arg, struct tep_record * 


		if (arg->str.field->flags & TEP_FIELD_IS_DYNAMIC) {

			addr = *(unsigned int *)val;

			val = record->data + (addr & 0xffff);

			size = addr >> 16;

			addr &= 0xffff;

			if (arg->str.field->flags & TEP_FIELD_IS_RELATIVE)

				addr += arg->str.field->offset + arg->str.field->size;

			val = record->data + addr;

		}



		/*