Another simplification made possible by using a plain char string
instead of string_t, that was only needed in the core as prep work
for CTF encoding.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since we stopped using per-cu obstacks we don't need it. If we ever
want to use it we can do per thread obstacks.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since we stopped using per-cu obstacks we don't need it. If we ever
want to use it we can do per thread obstacks.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since we stopped using per-cu obstacks we don't need it. If we ever
want to use it we can do per thread obstacks.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since we stopped using per-cu obstacks we don't need it. If we ever
want to use it we can do per thread obstacks.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now that we stopped using string indexes, no need for that, just set
namespace->name with the new class name.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the threaded code we want to access strings in tags at the same time
that the string table may grow in another thread making the previous
pointer invalid, so, to avoid excessive locking, use plain strings.
The way the tools work will either consume the just produced CU straight
away or keep just one copy of each data structure when we keep all CUs
in memory, so lets try stopping using strings_t for strings.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the threaded code we want to access strings in tags at the same time
that the string table may grow in another thread making the previous
pointer invalid, so, to avoid excessive locking, use plain strings.
The way the tools work will either consume the just produced CU straight
away or keep just one copy of each data structure when we keep all CUs
in memory, so lets try stopping using strings_t for strings.
For the enumerator->name case we get the bonus of removing the last user
of dwarves__active_loader in the btf_encoder class.
This covers unions, enums, structs and classes.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the threaded code we want to access strings in tags at the same time
that the string table may grow in another thread making the previous
pointer invalid, so, to avoid excessive locking, use plain strings.
The way the tools work will either consume the just produced CU straight
away or keep just one copy of each data structure when we keep all CUs
in memory, so lets try stopping using strings_t for strings.
For the namespace->name case we get the bonus of removing another
user of dwarves__active_loader.
This covers unions, enums, structs and classes.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the threaded code we want to access strings in tags at the same time
that the string table may grow in another thread making the previous
pointer invalid, so, to avoid excessive locking, use plain strings.
The way the tools work will either consume the just produced CU straight
away or keep just one copy of each data structure when we keep all CUs
in memory, so lets try stopping using strings_t for strings.
For the class_member->name case we get the bonus of removing another
user of dwarves__active_loader.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the threaded code we want to access strings in tags at the same time
that the string table may grow in another thread making the previous
pointer invalid, so, to avoid excessive locking, use plain strings.
The way the tools work will either consume the just produced CU straight
away or keep just one copy of each data structure when we keep all CUs
in memory, so lets try stopping using strings_t for strings.
For the base_type->name case we get the bonus of removing some more
functions related base types and a user of dwarves__active_loader.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the threaded code we want to access strings in tags at the same time
that the string table may grow in another thread making the previous
pointer invalid, so, to avoid excessive locking, use plain strings.
The way the tools work will either consume the just produced CU straight
away or keep just one copy of each data structure when we keep all CUs
in memory, so lets try stopping using strings_t for strings.
For the function->name case we get the bonus of removing the need of a
debug_fmt_ops->function() callback receiving the 'cu', just access the
string directly.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This one just allows that to be set, i.e.:
$ pahole -C perf_event_header ~/bin/perf
struct perf_event_header {
__u32 type; /* 0 4 */
__u16 misc; /* 4 2 */
__u16 size; /* 6 2 */
/* size: 8, cachelines: 1, members: 3 */
/* last cacheline: 8 bytes */
};
$ pahole -C 'perf_event_header(sizeof=size)' --seek_bytes=0x348 --count 1 ~/bin/perf < perf.data
{
.type = 0xa,
.misc = 0x2,
.size = 0x68,
},
$
But:
$ pahole -C 'perf_event_header(sizeof=bla)' --seek_bytes=0x348 --count 1 ~/bin/perf < perf.data
pahole: the sizeof member 'bla' not found in the 'perf_event_header' type
$
And:
$ pahole -C 'perf_event_header(size=misc)' --seek_bytes=0x348 --count 1 ~/bin/perf < perf.data
pahole: invalid arg 'size' in 'perf_event_header(size=misc)' (known args: sizeof=member)
$
The next cset will implement sizeof(type) with that modifier, using the
stdin bytes to obtain the size (0x68) in the above case, and then we'll
be able to print a sequence of variable-sized records correctly.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch records for each CU whether it's in little-endian or
big-endian data format. This flag will be used in subsequent commits to
adjust bit offsets where necessary, to make them uniform across
endianness. This patch doesn't have any effect on pahole's output.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Mark Wielaard <mark@klomp.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: dwarves@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
the CTF and BTF loaders come already with the id to use, while the DWARF
loader comes with a Dwarf_Off that needs to be converted into the
ptr_table index.
So keep the cu__add_tag(cu, tag, &id) method to ask ask for the index to
be allocated in the ptr_table and the result to come back via the 'id'
parameter, now a uint32_t and introduce a cu__add_tag_with_id(cu, tag, id)
method to indicate that the 'uint32_t id' is the one to use.
With this we can use a uint32_t for the id both on 32-bit and 64-bit
arches.
Reported-by: Andrii Nakryiko <andriin@fb.com>
Tested-by:Andrii Nakryiko <andrii.nakryiko@gmail.com>
Link: https://lore.kernel.org/bpf/CAEf4Bzb0SpvXdDKMMnUof==kp4Y0AP54bKFjeCzX_AsmDm7k7g@mail.gmail.com/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We'll use location in the DWARF sense, i.e. location lists, etc, i.e.
where is this variable? In a register? The stack? etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As Thomas Gleixner wisely pointed out, using 'self' is stupid, it
doesn't convey useful information, so use sensible names.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding an enum so that CTF doesn't have to include dwarf.h and
setting the language to LANG_C in the CTF loader.
Next csets will handle C++ in a different way, because we may need
to find class sizes in a different CU since ancestors sometimes
are only forward declared...
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Next we'll add a new kind of tag, DW_TAG_perf_counter, that will come
from perf.data generated by 'perf report'.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There is still the problem of handing the strings table to the CTF encoder, but
that will be fixed another day.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we can use the strings in ".strtab" directly, without duplicating them
on the global strings table.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Such as signed, etc. This is in preparation for using directly ctf_strings.
Instead of duplicating it in the global strings table.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Temporary hack till I figure out how to do more filtering on the variables on
the symtab that aren't in the DWARF info.
Problem is that if we don't put something on the table at encode time, we won't
find it at decode time, when we don't have DWARF to notice that its not there
because its not in DWARF.
We then discard it at load time, as "void foo;" doesn't make sense.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That is done by adding some new struct debug_fmt_ops methods:
->function__name()
This one, if specified, will be called by function__name(), giving a chance to
formats such as CTF to get this from some other place than the global strings
table. CTF does this by storing GElf_Sym->st_name in function->name, and by
providing a dfops->function__name() that uses function->name as an index into
the .strtab ELF section.
->cu__delete()
This is needed because we can't anymore call ctf__delete at the end of
ctf__load_file, as we will need at least the .strstab ELF section to be
available till we're done with the cu, i.e. till we call cu__delete(), that now
calls dfops->cu__delete() if it is available.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Encoding all the non UNDEF OBJECT entries in the symtab. Some must be filtered
in upcoming patches, but for at least kernel/sched.o it works just fine.
To test it I used DaveM's ctfdump and also pdwtags on a --strip-debug, pahole
-Z CTF encoded object.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And ditch the iterate calling a function interface. I'm trying to get rid of
that in the core (cu__for_each+callback+filter, etc) because doit it
explicitely, like in the kernel, where you have a foo__for_each_bar and do the
filtering directly and process the data, if the processing is simple, right in
the body of the loop, instead of having to go back and forth thru functions.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Moving more CTF only stuff out of the dwarves land and into something that can
be more easily stolen by other projects not interested in funny named stuff
such as pahole.
This also will help with encoding, as we will normally be recoding data from
DWARF, so the ELF file will be available and we will just add a new section to
it.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Kui-Feng Lee
Arnaldo Carvalho de Melo
Andrii Nakryiko