linux.git/tools/perf/util/dso.c, branch v6.9

perf annotate-data: Add dso->data_types tree

2023-12-24T01:39:42+00:00

To aggregate accesses to the same data type, add 'data_types' tree in
DSO to maintain data types and find it by name and size.

It might have different data types that happen to have the same name,
so it also compares the size of the type.

Even if it doesn't 100% guarantee, it reduces the possibility of
mis-handling of such conflicts.

And I don't think it's common to have different types with the same
name.

Committer notes:

Very few cases on the Linux kernel, but there are some different types
with the same name, unsure if there is a debug mode in libbpf dedup that
warns about such cases, but there are provisions in pahole for that,
see:

  "emit: Notice type shadowing, i.e. multiple types with the same name (enum, struct, union, etc)"
    https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=4f332dbfd02072e4f410db7bdcda8d6e3422974b

  $ pahole --compile > vmlinux.h
  $ rm -f a ; make a
  cc     a.c   -o a
  $ grep __[0-9] vmlinux.h
  union irte__1 {
  struct map_info__1;
  struct map_info__1 {
  	struct map_info__1 *       next;                 /*     0     8 */
  $

  drivers/iommu/amd/amd_iommu_types.h 'union irte'
  include/linux/dmar.h                'struct irte'

  include/linux/device-mapper.h:

    union map_info {
            void *ptr;
    };

  include/linux/mtd/map.h:

    struct map_info {
        const char *name;
        unsigned long size;
        resource_size_t phys;
   

  kernel/events/uprobes.c:

   struct map_info {
        struct map_info *next;
        struct mm_struct *mm;
        unsigned long vaddr;
  };

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools/perf: Add "is_kmod" to struct dso to check if it is kernel module

2023-10-05T05:28:07+00:00

Update "struct dso" to include new member "is_kmod".
This new field will determine if the file is a kernel
module or not.

To resolve the address from a sample, perf looks at the
DSO maps. In case of address from a kernel module, there
were some address found to be not resolved. This was
observed while running perf test for "Object code reading".
Though the ip falls beteen the start address of the loaded
module (perf map->start ) and end address ( perf map->end),
it was unresolved.

This was happening because in some cases for kernel
modules, address from sample points to stub instructions.
To identify if the DSO is a kernel module, the new field
"is_kmod" is added to "struct dso".

Reported-by: Disha Goel 
Signed-off-by: Athira Rajeev 
Acked-by: Namhyung Kim 
Cc: kjain@linux.ibm.com
Cc: maddy@linux.ibm.com
Cc: disgoel@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230928075213.84392-2-atrajeev@linux.vnet.ibm.com
Signed-off-by: Namhyung Kim

perf symbol: Remove symbol_name_rb_node

2023-06-24T04:47:20+00:00

Most perf commands want to sort symbols by name and this is done via
an invasive rbtree that on 64-bit systems costs 24 bytes. Sorting the
symbols in a DSO by name is optional and not done by default, however,
if sorting is requested the 24 bytes is allocated for every
symbol.

This change removes the rbtree and uses a sorted array of symbol
pointers instead (costing 8 bytes per symbol). As the array is created
on demand then there are further memory savings. The complexity of
sorting the array and using the rbtree are the same.

To support going to the next symbol, the index of the current symbol
needs to be passed around as a pair with the current symbol. This
requires some API changes.

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Cc: Carsten Haitzler 
Cc: Mark Rutland 
Cc: Jason Wang 
Cc: Changbin Du 
Cc: Yang Jihong 
Cc: Peter Zijlstra 
Cc: Adrian Hunter 
Cc: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Kan Liang 
Cc: Athira Rajeev 
Cc: Ingo Molnar 
Cc: Christophe JAILLET 
Link: https://lore.kernel.org/r/20230623054520.4118442-3-irogers@google.com
[ minimize change in symbols__sort_by_name() ]
Signed-off-by: Namhyung Kim

perf script: Refine printing of dso offset (dsoff)

2023-05-12T18:21:49+00:00

Print dso offset only for object files, and in those cases force using the
dso->long_name if the dso->name starts with '[' or the dso is kcore, in
order to avoid special names such as [vdso], or mixing up kcore with
vmlinux.

Signed-off-by: Adrian Hunter 
Cc: Changbin Du 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/r/20230424055107.12105-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dso: Add dso__filename_with_chroot() to reduce number of accesses to dso->nsinfo members

2023-04-17T21:47:55+00:00

We'll need to reference count dso->nsinfo, so reduce the number of
direct accesses by having a shorter form of obtaining a filename with
a chroot (namespace one).

Cc: Adrian Hunter 
Cc: Alexey Bayduraev 
Cc: Dmitriy Vyukov 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Riccardo Mancini 
Cc: Stephane Eranian 
Cc: Stephen Brennan 
Link: https://lore.kernel.org/lkml/ZD26ZlqSbgSyH5lX@kernel.org
[ Used nsinfo__pid(dso->nsinfo), as it was already present ]
Signed-off-by: Arnaldo Carvalho de Melo

perf map: Add helper for ->map_ip() and ->unmap_ip()

2023-04-07T01:10:17+00:00

Later changes will add reference count checking for struct map, add a
helper function to invoke the map_ip and unmap_ip function pointers. The
helper allows the reference count check to be in fewer places.

Committer notes:

Add missing conversions to:

  tools/perf/util/map.c
  tools/perf/util/cs-etm.c
  tools/perf/util/annotate.c
  tools/perf/arch/powerpc/util/sym-handling.c
  tools/perf/arch/s390/annotate/instructions.c

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexey Bayduraev 
Cc: Andi Kleen 
Cc: Andrew Morton 
Cc: Andy Shevchenko 
Cc: Darren Hart 
Cc: Davidlohr Bueso 
Cc: Dmitriy Vyukov 
Cc: Eric Dumazet 
Cc: German Gomez 
Cc: Hao Luo 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Miaoqian Lin 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Shunsuke Nakamura 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Stephen Brennan 
Cc: Steven Rostedt (VMware) 
Cc: Thomas Gleixner 
Cc: Thomas Richter 
Cc: Yury Norov 
Link: https://lore.kernel.org/r/20230404205954.2245628-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dso: Hold lock when accessing nsinfo

2022-10-04T11:55:20+00:00

There may be threads racing to update dso->nsinfo:

  https://lore.kernel.org/linux-perf-users/CAP-5=fWZH20L4kv-BwVtGLwR=Em3AOOT+Q4QGivvQuYn5AsPRg@mail.gmail.com/

Holding the dso->lock avoids use-after-free, memory leaks and other such
bugs. Apply the fix in:

  https://lore.kernel.org/linux-perf-users/20211118193714.2293728-1-irogers@google.com/

of there being a missing nsinfo__put now that the accesses are data race
free. Fixes test "Lookup mmap thread" when compiled with address
sanitizer.

Signed-off-by: Ian Rogers 
Reviewed-by: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexandre Truong 
Cc: Alexey Bayduraev 
Cc: Andi Kleen 
Cc: Andres Freund 
Cc: Andrii Nakryiko 
Cc: André Almeida 
Cc: Athira Jajeev 
Cc: Christophe JAILLET 
Cc: Colin Ian King 
Cc: Dario Petrillo 
Cc: Darren Hart 
Cc: Dave Marchevsky 
Cc: Davidlohr Bueso 
Cc: Fangrui Song 
Cc: Hewenliang 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jason Wang 
Cc: Jiri Olsa 
Cc: Kajol Jain 
Cc: Kim Phillips 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Martin Liška 
Cc: Masami Hiramatsu 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Pavithra Gurushankar 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Ravi Bangoria 
Cc: Remi Bernon 
Cc: Riccardo Mancini 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Cc: Thomas Richter 
Cc: Tom Rix 
Cc: Weiguo Li 
Cc: Wenyu Liu 
Cc: William Cohen 
Cc: Zechuan Chen 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: yaowenbin 
Link: https://lore.kernel.org/r/20220826164242.43412-15-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dso: Update use of pthread mutex

2022-10-04T11:55:20+00:00

Switch to the use of mutex wrappers that provide better error checking.

Signed-off-by: Ian Rogers 
Reviewed-by: Adrian Hunter 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Alexandre Truong 
Cc: Alexey Bayduraev 
Cc: Andi Kleen 
Cc: Andres Freund 
Cc: Andrii Nakryiko 
Cc: André Almeida 
Cc: Athira Jajeev 
Cc: Christophe JAILLET 
Cc: Colin Ian King 
Cc: Dario Petrillo 
Cc: Darren Hart 
Cc: Dave Marchevsky 
Cc: Davidlohr Bueso 
Cc: Fangrui Song 
Cc: Hewenliang 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jason Wang 
Cc: Jiri Olsa 
Cc: Kajol Jain 
Cc: Kim Phillips 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Martin Liška 
Cc: Masami Hiramatsu 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Pavithra Gurushankar 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Ravi Bangoria 
Cc: Remi Bernon 
Cc: Riccardo Mancini 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Cc: Thomas Richter 
Cc: Tom Rix 
Cc: Weiguo Li 
Cc: Wenyu Liu 
Cc: William Cohen 
Cc: Zechuan Chen 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: yaowenbin 
Link: https://lore.kernel.org/r/20220826164242.43412-12-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Try chroot'ed filename when opening dso/symbol

2022-02-10T18:32:25+00:00

Currently it doesn't handle tasks in chroot properly.  As filenames in
MMAP records base on their root directory, it's different than what perf
tool can see from outside.

Add filename_with_chroot() helper to deal with those cases.  The
function returns a new filename only if it's in a different root
directory.  Since it needs to access /proc for the process, it only
works until the task exits.

With this change, I can see symbols in my program like below.

  # perf record -o- chroot myroot myprog 3 | perf report -i-
  ...
  #
  # Overhead  Command  Shared Object      Symbol
  # ........  .......  .................  .............................
  #
      99.83%  myprog   myprog             [.] loop
       0.04%  chroot   [kernel.kallsyms]  [k] fxregs_fixup
       0.04%  chroot   [kernel.kallsyms]  [k] rsm_load_seg_32
  ...

Signed-off-by: Namhyung Kim 
Acked-by: Jiri Olsa 
Cc: Andi Kleen 
Cc: Ian Rogers 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20220202070828.143303-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Pull in bpf_program__get_prog_info_linear()

2021-11-01T21:16:40+00:00

To prepare for impending deprecation of libbpf's bpf_program__get_prog_info_linear(),
pull in the function and associated helpers into the perf codebase and migrate
existing uses to the perf copy.

Since libbpf's deprecated definitions will still be visible to perf, it is necessary
to rename perf's definitions.

Signed-off-by: Dave Marchevsky 
Acked-by: Andrii Nakryiko 
Acked-by: Song Liu 
Cc: Alexei Starovoitov 
Cc: Daniel Borkmann 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20211011082031.4148337-4-davemarchevsky@fb.com
Signed-off-by: Arnaldo Carvalho de Melo