Will be useful to show that the intent is to traverse just the DW_TAG_member
entries in the type list. Right now there are both DW_TAG_inheritance and
DW_TAG_member entries in the ->members type list. But there will be many more
tags, like enumerations, classes, etc, that are defined inside classes, a C++
feature. This will also help with DW_TAG_namespace support.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
First user is pahole, that now has a --contains CLASS_NAME option, that will
show which classes contains CLASS_NAME, i.e.:
struct foo {
struct bar baz;
int i;
};
on an object file called with '--contains bar' will produce:
foo
if --verbose is used it will tell the number of CLASS_NAME members, so, in the
above example:
foo:1
Next thing will be a --recursive flag, that will show all the structs that
contains CLASS_NAME and the ones that contains the ones which contains and...
:-)
Useful to evaluate the impact that increasing or decreasing the size of some
important struct will have on the whole project that uses the struct.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
By default, pahole will display the offsets of the inner struct members from
the top level struct. If the user wants to focus on some inner structs, just
call the tool with the -r option to use relative offset instead of the base
offset.
Signed-off-by: Eugene Teo <eteo@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
So that we can go on adding more config knobs without requiring adding new
parameters to lots of functions.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
1. if the first member is a bitfield, we have to have set current_bitfield_size to 0
prior to entering the loop.
2. If sizeof(last member) == 0, don't try to move it
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Confusing huh? Think about ____cacheline_aligned_in_smp, and you'll get the
idea, look at this patch inline comment to understand the issue.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
E.g. in struct net_device when moving sysfs_groups[3] to after reg_state,
sizeof(sisfs_groups[3]) is 24 and the hole found after some reorganizing after
reg_state is 80 bytes, so align it just after reg_state, not 8 bytes after it.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Now there is a cus__loadfl function that receives the tool argp tables and uses
libdwfl to process the DWARF info, with this RELA objects such as .o and .ko
files in a Linux kernel build are supported, and all the other goodies that
come from using libdwfl, such as separate debuginfo files, etc come as a bonus.
Now to convert the tools, pahole being the first, that already works well using
cus__loadfl().
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
[acme@filo examples]$ pahole -a mpg_audio_frame_t
/* <14f> /home/acme/git/pahole/examples/mpg_audio_frame_t.c:4 */
typedef struct {
uint16_t frame_sync; /* 0 2 */
uint8_t layer; /* 2 1 */
/* WARNING: DWARF offset=0, real offset=3 */
uint32_t mpeg25_bit:1; /* 0 4 */
uint32_t lsf_bit:1; /* 0 4 */
uint32_t bitrate_idx:4; /* 0 4 */
<SNIP>
So gcc combined a uint16_t + a uint8_t + the first entries in the uint32_t
bitfield that could fit in the 8 bits after the first two fields but haven't
updated the size of the bitfield (4) and wrote 0 as the offset, warn about such
inconsistencies.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
So that we print the boundary after the last member in a bitfield.
Spotted by Matthew Wilcox.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
[acme@mica pahole]$ pahole lala
pahole: Permission denied
[acme@mica pahole]$ pahole foo
pahole: No such file or directory
[acme@mica pahole]$ pahole ctracer.c
pahole: couldn't load DWARF info from ctracer.c
[acme@mica pahole]$
Thanks to Matthew Wilcox for noticing how lame it was :-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
[acme@filo pahole]$ cat examples/expand_typedefs.c
<SNIP>
typedef struct {
int a, b, c;
} inner;
static struct outer {
int q, b;
inner m;
} foo;
<SNIP>
[acme@filo pahole]$ pahole --expand_types examples/expand_typedefs
/* <158> /home/acme/git/pahole/examples/expand_typedefs.c:7 */
struct outer {
int q; /* 0 4 */
int b; /* 4 4 */
/* typedef inner */ struct {
int a; /* 0 4 */
int b; /* 4 4 */
int c; /* 8 4 */
} m; /* 8 12 */
}; /* size: 20, cachelines: 1 */
/* last cacheline: 20 bytes */
/* definitions: 1 */
[acme@filo pahole]$
For now it does all typedef expansions, which in at least the base types may be
a bit too much, e.g. u32 -> unsigned long int, lets see if somebody complains,
perhaps even myself 8) If that is the case we can add yet another command line
option to specify that such base type expansions should be filtered out, making
the expand_types parameter be flag mask, not just a boolean as it is today.
To see a more complete output look at:
http://oops.ghostprotocols.net:81/acme/dwarves/vmlinux-pahole-expand_types-typedef_unfolding.txt
Suggested by Jeff Muizelaar.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we get rid of all the buffer limits, if we need to format into strings
we can use string streams, like we're doing now in just one case, tag__name for
DW_TAG_subroutine_type, that is bogus as it is, as we need to have the name of
the type inside the type declaration (void (*type_name)(parameters)) and not
after (void (*)(parameters) type_name)), but leave this for an upcoming cset.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And use it in a new tool, pglobal, that shows global variables and functions.
Signed-off-by: Davi Arnaut <davi@haxent.com.br>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>