Rename enum dso_kernel_type to enum dso_space_type, which seems like
better fit.
Committer notes:
This is used with 'struct dso'->kernel, which once was a boolean, so
DSO_SPACE__USER is zero, !zero means some sort of kernel space, be it
the host kernel space or a guest kernel space.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The dso->kernel value is now set to everything that is in
machine->kmaps, but that was being used to decide if vmlinux lookup is
needed, which ended up making that lookup be made for kernel modules,
that now have dso->kernel set, leading to these kinds of warnings when
running on a machine with compressed kernel modules, like fedora:31:
[root@five ~]# perf record -F 10000 -a sleep 2
[ perf record: Woken up 1 times to write data ]
lzma: fopen failed on vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
lzma: fopen failed on vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
lzma: fopen failed on vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
lzma: fopen failed on vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
lzma: fopen failed on vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
[ perf record: Captured and wrote 1.024 MB perf.data (1366 samples) ]
[root@five ~]#
This happens when collecting the buildid, when we find samples for
kernel modules, fix it by checking if the looked up DSO is a kernel
module by other means.
Fixes: 02213cec64 ("perf maps: Mark module DSOs with kernel type")
Tested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200302191007.GD10335@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And pick the shortest name: 'struct maps'.
The split existed because we used to have two groups of maps, one for
functions and one for variables, but that only complicated things,
sometimes we needed to figure out what was at some address and then had
to first try it on the functions group and if that failed, fall back to
the variables one.
That split is long gone, so for quite a while we had only one struct
maps per struct map_groups, simplify things by combining those structs.
First patch is the minimum needed to merge both, follow up patches will
rename 'thread->mg' to 'thread->maps', etc.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are still lots of lookups by name, even if just when loading
vmlinux, till that code is studied to figure out if its possible to do
away with those map lookup by names, provide a way to sort it using
libc's qsort/bsearch.
Doing it at the first lookup defers the sorting a bit, and as the code
stands now, is never done for user maps, just for the kernel ones.
# perf probe -l
# perf probe -x ~/bin/perf -L __map_groups__find_by_name
<__map_groups__find_by_name@/home/acme/git/perf/tools/perf/util/symbol.c:0>
0 static struct map *__map_groups__find_by_name(struct map_groups *mg, const char *name)
1 {
struct map **mapp;
4 if (mg->maps_by_name == NULL &&
5 map__groups__sort_by_name_from_rbtree(mg))
6 return NULL;
8 mapp = bsearch(name, mg->maps_by_name, mg->nr_maps, sizeof(*mapp), map__strcmp_name);
9 if (mapp)
10 return *mapp;
11 return NULL;
12 }
struct map *map_groups__find_by_name(struct map_groups *mg, const char *name)
{
# perf probe -x ~/bin/perf 'found=__map_groups__find_by_name:10 name:string'
Added new event:
probe_perf:found (on __map_groups__find_by_name:10 in /home/acme/bin/perf with name:string)
You can now use it in all perf tools, such as:
perf record -e probe_perf:found -aR sleep 1
#
# perf probe -x ~/bin/perf -L map_groups__find_by_name
<map_groups__find_by_name@/home/acme/git/perf/tools/perf/util/symbol.c:0>
0 struct map *map_groups__find_by_name(struct map_groups *mg, const char *name)
1 {
2 struct maps *maps = &mg->maps;
struct map *map;
5 down_read(&maps->lock);
7 if (mg->last_search_by_name && strcmp(mg->last_search_by_name->dso->short_name, name) == 0) {
8 map = mg->last_search_by_name;
9 goto out_unlock;
}
/*
* If we have mg->maps_by_name, then the name isn't in the rbtree,
* as mg->maps_by_name mirrors the rbtree when lookups by name are
* made.
*/
16 map = __map_groups__find_by_name(mg, name);
17 if (map || mg->maps_by_name != NULL)
18 goto out_unlock;
/* Fallback to traversing the rbtree... */
21 maps__for_each_entry(maps, map)
22 if (strcmp(map->dso->short_name, name) == 0) {
23 mg->last_search_by_name = map;
24 goto out_unlock;
}
27 map = NULL;
out_unlock:
30 up_read(&maps->lock);
31 return map;
32 }
int dso__load_vmlinux(struct dso *dso, struct map *map,
const char *vmlinux, bool vmlinux_allocated)
# perf probe -x ~/bin/perf 'fallback=map_groups__find_by_name:21 name:string'
Added new events:
probe_perf:fallback (on map_groups__find_by_name:21 in /home/acme/bin/perf with name:string)
probe_perf:fallback_1 (on map_groups__find_by_name:21 in /home/acme/bin/perf with name:string)
You can now use it in all perf tools, such as:
perf record -e probe_perf:fallback_1 -aR sleep 1
#
# perf probe -l
probe_perf:fallback (on map_groups__find_by_name:21@util/symbol.c in /home/acme/bin/perf with name_string)
probe_perf:fallback_1 (on map_groups__find_by_name:21@util/symbol.c in /home/acme/bin/perf with name_string)
probe_perf:found (on __map_groups__find_by_name:10@util/symbol.c in /home/acme/bin/perf with name_string)
#
# perf stat -e probe_perf:*
Now run 'perf top' in another term and then, after a while, stop 'perf stat':
Furthermore, if we ask for interval printing, we can see that that is done just
at the start of the workload:
# perf stat -I1000 -e probe_perf:*
# time counts unit events
1.000319513 0 probe_perf:found
1.000319513 0 probe_perf:fallback_1
1.000319513 0 probe_perf:fallback
2.001868092 23,251 probe_perf:found
2.001868092 0 probe_perf:fallback_1
2.001868092 0 probe_perf:fallback
3.002901597 0 probe_perf:found
3.002901597 0 probe_perf:fallback_1
3.002901597 0 probe_perf:fallback
4.003358591 0 probe_perf:found
4.003358591 0 probe_perf:fallback_1
4.003358591 0 probe_perf:fallback
^C
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-c5lmbyr14x448rcfii7y6t3k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Lets see if it helps:
First look at the probeable lines for the function that does lookups by
name in a map_groups struct:
# perf probe -x ~/bin/perf -L map_groups__find_by_name
<map_groups__find_by_name@/home/acme/git/perf/tools/perf/util/symbol.c:0>
0 struct map *map_groups__find_by_name(struct map_groups *mg, const char *name)
1 {
2 struct maps *maps = &mg->maps;
struct map *map;
5 down_read(&maps->lock);
7 if (mg->last_search_by_name && strcmp(mg->last_search_by_name->dso->short_name, name) == 0) {
8 map = mg->last_search_by_name;
9 goto out_unlock;
}
12 maps__for_each_entry(maps, map)
13 if (strcmp(map->dso->short_name, name) == 0) {
14 mg->last_search_by_name = map;
15 goto out_unlock;
}
18 map = NULL;
out_unlock:
21 up_read(&maps->lock);
22 return map;
23 }
int dso__load_vmlinux(struct dso *dso, struct map *map,
const char *vmlinux, bool vmlinux_allocated)
#
Now add a probe to the place where we reuse the last search:
# perf probe -x ~/bin/perf map_groups__find_by_name:8
Added new event:
probe_perf:map_groups__find_by_name (on map_groups__find_by_name:8 in /home/acme/bin/perf)
You can now use it in all perf tools, such as:
perf record -e probe_perf:map_groups__find_by_name -aR sleep 1
#
Now lets do a system wide 'perf stat' counting those events:
# perf stat -e probe_perf:*
Leave it running and lets do a 'perf top', then, after a while, stop the
'perf stat':
# perf stat -e probe_perf:*
^C
Performance counter stats for 'system wide':
3,603 probe_perf:map_groups__find_by_name
44.565253139 seconds time elapsed
#
yeah, good to have.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-tcz37g3nxv3tvxw3q90vga3p@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And then stop using map->groups to achieve that.
To test that that branch is being taken, probe the function that is only
called from there and then run something like 'perf top' in another
xterm:
# perf probe -x ~/bin/perf machine__map_x86_64_entry_trampolines
Added new event:
probe_perf:machine__map_x86_64_entry_trampolines (on machine__map_x86_64_entry_trampolines in /home/acme/bin/perf)
You can now use it in all perf tools, such as:
perf record -e probe_perf:machine__map_x86_64_entry_trampolines -aR sleep 1
# perf trace -e probe_perf:*
0.000 bash/10614 probe_perf:machine__map_x86_64_entry_trampolines(__probe_ip: 5224944)
^C#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-lgrrzdxo2p9liq2keivcg887@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have already implemented some block-info related functions.
Now it's time to do some cleanup, refactoring and move the
functions and structures to new block-info.h/block-info.c.
v4:
---
Move code for skipping column length calculation to patch:
'perf diff: Don't use hack to skip column length calculation'
v3:
---
1. Rename the patch title
2. Rename from block.h/block.c to block-info.h/block-info.c
3. Move more common part to block-info, such as
block_info__process_sym.
4. Remove the nasty hack for skipping calculation of column
length
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20191107074719.26139-3-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
During execution of command 'perf top' the error message:
Not enough memory for annotating '__irf_end' symbol!)
is emitted from this call sequence:
__cmd_top
perf_top__mmap_read
perf_top__mmap_read_idx
perf_event__process_sample
hist_entry_iter__add
hist_iter__top_callback
perf_top__record_precise_ip
hist_entry__inc_addr_samples
symbol__inc_addr_samples
symbol__get_annotation
symbol__alloc_hist
In this function the size of symbol __irf_end is calculated. The size of
a symbol is the difference between its start and end address.
When the symbol was read the first time, its start and end was set to:
symbol__new: __irf_end 0xe954d0-0xe954d0
which is correct and maps with /proc/kallsyms:
root@s8360046:~/linux-4.15.0/tools/perf# fgrep _irf_end /proc/kallsyms
0000000000e954d0 t __irf_end
root@s8360046:~/linux-4.15.0/tools/perf#
In function symbol__alloc_hist() the end of symbol __irf_end is
symbol__alloc_hist sym:__irf_end start:0xe954d0 end:0x3ff80045a8
which is identical with the first module entry in /proc/kallsyms
This results in a symbol size of __irf_req for histogram analyses of
70334140059072 bytes and a malloc() for this requested size fails.
The root cause of this is function
__dso__load_kallsyms()
+-> symbols__fixup_end()
Function symbols__fixup_end() enlarges the last symbol in the kallsyms
map:
# fgrep __irf_end /proc/kallsyms
0000000000e954d0 t __irf_end
#
to the start address of the first module:
# cat /proc/kallsyms | sort | egrep ' [tT] '
....
0000000000e952d0 T __security_initcall_end
0000000000e954d0 T __initramfs_size
0000000000e954d0 t __irf_end
000003ff800045a8 T fc_get_event_number [scsi_transport_fc]
000003ff800045d0 t store_fc_vport_disable [scsi_transport_fc]
000003ff800046a8 T scsi_is_fc_rport [scsi_transport_fc]
000003ff800046d0 t fc_target_setup [scsi_transport_fc]
On s390 the kernel is located around memory address 0x200, 0x10000 or
0x100000, depending on linux version. Modules however start some- where
around 0x3ff xxxx xxxx.
This is different than x86 and produces a large gap for which histogram
allocation fails.
Fix this by detecting the kernel's last symbol and do no adjustment for
it. Introduce a weak function and handle s390 specifics.
Reported-by: Klaus Theurich <klaus.theurich@de.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20190724122703.3996-2-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We got the sane_ctype.h headers from git and kept using it so far, but
since that code originally came from the kernel sources to the git
sources, perhaps its better to just use the one in the kernel, so that
we can leverage tools/perf/check_headers.sh to be notified when our copy
gets out of sync, i.e. when fixes or goodies are added to the code we've
copied.
This will help with things like tools/lib/string.c where we want to have
more things in common with the kernel, such as strim(), skip_spaces(),
etc so as to go on removing the things that we have in tools/perf/util/
and instead using the code in the kernel, indirectly and removing things
like EXPORT_SYMBOL(), etc, getting notified when fixes and improvements
are made to the original code.
Hopefully this also should help with reducing the difference of code
hosted in tools/ to the one in the kernel proper.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-7k9868l713wqtgo01xxygn12@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce a new dso type DSO_BINARY_TYPE__BPF_PROG_INFO for BPF programs. In
symbol__disassemble(), DSO_BINARY_TYPE__BPF_PROG_INFO dso will call into a new
function symbol__disassemble_bpf() in an upcoming patch, where annotation line
information is filled based bpf_prog_info and btf saved in given perf_env.
Committer notes:
Removed the unnamed union with 'bpf_prog' and 'cache' in 'struct dso',
to fix this bug when exiting 'perf top':
# perf top
perf: Segmentation fault
-------- backtrace --------
perf[0x5a785a]
/lib64/libc.so.6(+0x385bf)[0x7fd68443c5bf]
perf(rb_first+0x2b)[0x4d6eeb]
perf(dso__delete+0xb7)[0x4dffb7]
perf[0x4f9e37]
perf(perf_session__delete+0x64)[0x504df4]
perf(cmd_top+0x1957)[0x454467]
perf[0x4aad18]
perf(main+0x61c)[0x42ec7c]
/lib64/libc.so.6(__libc_start_main+0xf2)[0x7fd684428412]
perf(_start+0x2d)[0x42eead]
#
# addr2line -fe ~/bin/perf 0x4dffb7
dso_cache__free
/home/acme/git/perf/tools/perf/util/dso.c:713
That is trying to access the dso->data.cache, and that is not used with
BPF programs, so we end up accessing what is in bpf_prog.first_member,
b00m.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-13-songliubraving@fb.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now 'perf report' can show whole time periods with 'perf script', but
the user still has to find individual samples of interest manually.
It would be expensive and complicated to search for the right samples in
the whole perf file. Typically users only need to look at a small number
of samples for useful analysis.
Also the full scripts tend to show samples of all CPUs and all threads
mixed up, which can be very confusing on larger systems.
Add a new --samples option to save a small random number of samples per
hist entry.
Use a reservoir sample technique to select a representatve number of
samples.
Then allow browsing the samples using 'perf script' as part of the hist
entry context menu. This automatically adds the right filters, so only
the thread or cpu of the sample is displayed. Then we use less' search
functionality to directly jump the to the time stamp of the selected
sample.
It uses different menus for assembler and source display. Assembler
needs xed installed and source needs debuginfo.
Currently it only supports as many samples as fit on the screen due to
some limitations in the slang ui code.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20190311174605.GA29294@tassilo.jf.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Many workloads change over time. 'perf report' currently aggregates the
whole time range reported in perf.data.
This patch adds an option for a time quantum to quantisize the perf.data
over time.
This just adds the option, will be used in follow on patches for a time
sort key.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20190305144758.12397-6-andi@firstfloor.org
[ Use NSEC_PER_[MU]SEC ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Kallsyms symbols do not have a size, so the size becomes the distance to
the next symbol.
Consequently the recently added trampoline symbols end up with large
sizes because the trampolines are some distance from one another and the
main kernel map.
However, symbols that end outside their map can disrupt the symbol tree
because, after mapping, it can appear incorrectly that they overlap
other symbols.
Add logic to truncate symbol size to the end of the corresponding map.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: stable@vger.kernel.org
Fixes: d83212d5dd ("kallsyms, x86: Export addresses of PTI entry trampolines")
Link: http://lkml.kernel.org/r/20190109091835.5570-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf can take minutes to parse an image when -ffunction-section is used.
This is especially true with the kernel image when it is compiled this
way, which is the arm64 default since the patcheset "Enable deadcode
elimination at link time".
Perf organize maps using a rbtree. Whenever perf finds a new symbols, it
first searches this rbtree for the map it belongs to, by strcmp()'aring
section names. When it finds the map with the right name, it uses it to
add the symbol. With a usual image there aren't so many maps but when
using -ffunction-section there's basically one map per function. With
the kernel image that's north of 40,000 maps. For most symbols perf has
to parses the entire rbtree to eventually create a new map and add it.
Consequently perf spends most of the time browsing a rbtree that keeps
getting larger.
This performance fix introduces a secondary rbtree that indexes maps
based on the section name.
Signed-off-by: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Reviewed-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reviewed-by: David Aldridge <david.aldridge@oracle.com>
Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1542822679-25591-1-git-send-email-eric.saint.etienne@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We were not considering 'B' and 'b' (BSS, uninitialized data objects,
that gets set to zero at program start), do it so that we can resolve
more symbols in tools doing resolution of data operands, like 'perf c2c'.
When using vmlinux, i.e. an ELF symbol table, those were already
considered, as the decision was about STT_FUNC or STT_OBJECT, and the
later covers BSS symbols.
# grep -i ' b ' /proc/kallsyms | head -20 | tail -5
ffffffffa789d030 b execute_command
ffffffffa789d038 b initcall_command_line
ffffffffa789d040 b static_command_line
ffffffffa789d048 B ROOT_DEV
ffffffffa789d050 b once.73786
#
# readelf -s /lib/modules/`uname -r`/build/vmlinux | grep ROOT_DEV
79219: ffffffff8289d048 4 OBJECT GLOBAL DEFAULT 58 ROOT_DEV
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-z960xobig39ca1pmp5brl2fr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
