In pahole we started showing 'union' tags as well, and those are
represented by 'struct type', so be defensive in class__find_holes(),
checking if the tag is represented with a 'struct class'.
Tested-by: Andrii Nakryiko <andriin@fb.com>
Fixes: 31664d60ad ("pahole: Show tagged enums as well when no class is specified")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since tools like 'pahole' now shows unions in addition to structs.
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If we processed at least one file we should return 0 to mean success.
Fixes: 02a456f5f5 ("pahole: Search and use running kernel vmlinux when no file is passed")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Seems like a nice shortcut for kernel hackers, and one that makes sure
the right vmlinux file is used, as it reads the running kernel build id
from /sys/kernel/notes and then searches the well known path for vmlinux
files:
vmlinux
/boot/vmlinux
/boot/vmlinux-4.14.0+
/usr/lib/debug/boot/vmlinux-`uname -r`
/lib/modules/`uname -r`/build/vmlinux
/usr/lib/debug/lib/modules/`uname -r`/vmlinux
/usr/lib/debug/boot/vmlinux-`uname -r`.debug
To find one with a matching build id (.notes ELF section, then
nhdr->n_type == NT_GNU_BUILD_ID), just like the Linux kernel 'perf
tools', where this code comes from, with some minor modifications to
cope with not having symbol_conf, symfs, etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Take 'struct task_struct' in the Linux kernel, these fields:
/* --- cacheline 2 boundary (128 bytes) --- */
struct sched_entity se; /* 128 448 */
/* XXX last struct has 24 bytes of padding */
/* --- cacheline 9 boundary (576 bytes) --- */
struct sched_rt_entity rt; /* 576 48 */
The sched_entity struct has 24 bytes of padding, and that info would
only appear when printing 'struct task_struct' if class__find_holes()
had previously been run on 'struct sched_entity' which wasn't always the
case, make sure that happens.
This results in this extra stat being printed for 'struct task_struct':
/* paddings: 4, sum paddings: 38 */
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Need to read more on http://www.artima.com/cppsource/rvalue.html, but
handling it mostly like DW_TAG_typedef so that at least references to it
are resolved, we can get its byte size, etc.
FIXME: look at the vtable parameters, some are resolving to "(null)".
Reported-by: Benjamin Kosnik <bkoz@redhat.com>
Reported-by: Mark Wieelard <mjw@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=962571
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Silly bug, it was trying to return a negative index stating what file
had problems in the provided array, but if the first had problems it was
return -0, duh, fix it by returning the first as 1, etc.
With this, calling 'pdwtags non-existent-file' would return no errors
via $?.
Next csets will provide proper error messages, using what is in errno
and this index to tell what file has problems.
Reported-by: Eric Blake <eblake@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=949034
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As Thomas Gleixner wisely pointed out, using 'self' is stupid, it
doesn't convey useful information, so use sensible names.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Needed because it uses S_ISDIR. In the past this header probably was
being indirectly included. Noticed while building on RHEL6 Beta.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
[acme@doppio pahole]$ pahole -F ctf /media/tb/debuginfo/usr/lib/debug/usr/bin/greycstoration4integration.debug > /tmp/bla
<ERROR(tag__size:837): detected type loop: type=572, tag=const_type>
<ERROR(tag__size:837): detected type loop: type=572, tag=const_type>
[acme@doppio pahole]$
These type loops are problems in the CTF encoding, that should be fixed, but
should not cause the core code to segfault on an infinite recursion.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That asks dwarf_fprintf to always use "struct" in places where it would
use "class", because CTF doesn't have the "class" concept, so for
'regtest diffctf' sake, we use this.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It doesn't matter when using a traditional malloc/free allocator, but
with obstacks we need to do it in reverse order.
For the usual case where we successfully process an object this doesn't
matter, as when we started using obstacks we don't traverse all the tags
calling their destructors anymore, we just free the whole obstack in one
go.
Noticed when processing object files built from non-supported languages
such as FORTRAN and Pascal, where there are some DWARF tags that are not
supported, which makes the object file load to be prematurely aborted
and that calls destructors for things like classes and functions that in
turn free space for their parameter/member lists, which now have to be
done in reverse order.
We could just stop calling the destructors and then destroying the whole
obstack, but I think that partially processed files are a nice feature,
so keep the interface in a way that both obstacks and traditinal malloc
alocators can be used.
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>
That is used by cus__find_function_by_addr & cu__func_function_by_addr.
First user is pfunct --addr, but this is really for pfunct --annotate, that
will process a perf.data file generated by 'perf report', load the debugging
info and regenerate the functions (pfunct -TVi like) that had hits, using
libdisasm to show the assembly code, etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In the past we did integer testing, and testing against 0 was no problem, but
now they return NULL and we are back using strcmp, oops.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we can more early return if we can't process files for some supported
debugging format and as well release all resources allocated when dwarves__exit
is called.
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>
Instead pass thru cu__strings(cu, i) so that we can figure out if the
underlying debugging format handler can do that more efficiently, such as by
looking up directly the ELF section ".strtab".
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>
ctracer was segfaulting due to this problem.
Reported-by: Breno Leitão <leitao@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And not compare by string_t, as now it may not be on the global strings table,
so we have to give a chance to the underlying debug format to translate that to
a string for us.
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>
There are more things that should be handled differently, such as function
names coming from the .strtab ELF section instead of from the global strings_t
table.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Domenico Andreoli
Yonghong Song
Arnaldo Carvalho de Melo