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: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Masami Hiramatsu 2021-11-22 18:30:40 +09:00 committed by Steven Rostedt (VMware)
parent b466b13321
commit cd7729043b
3 changed files with 47 additions and 22 deletions

View File

@ -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;

View File

@ -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 {

View File

@ -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;
}
/*