linux.git/tools/perf/util/dsos.c, branch for-next

perf dso: Constify dso_id

2024-08-19T17:52:13+00:00

The passed dso_id is copied and so is never an out argument. Remove
its mutability.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Anne Macedo 
Cc: Arnd Bergmann 
Cc: Athira Rajeev 
Cc: Casey Chen 
Cc: Chaitanya S Prakash 
Cc: Colin Ian King 
Cc: Dominique Martinet 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jann Horn 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Masahiro Yamada 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Sun Haiyong 
Cc: Weilin Wang 
Cc: Yang Jihong 
Cc: Yunseong Kim 
Cc: Ze Gao 
Link: https://lore.kernel.org/r/20240817064442.2152089-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dsos: When adding a dso into sorted dsos maintain the sort order

2024-07-03T22:02:53+00:00

dsos__add would add at the end of the dso array possibly requiring a
later find to re-sort the array. Patterns of find then add were
becoming O(n*log n) due to the sorts. Change the add routine to be
O(n) rather than O(1) but to maintain the sorted-ness of the dsos
array so that later finds don't need the O(n*log n) sort.

Fixes: 3f4ac23a9908 ("perf dsos: Switch backing storage to array from rbtree/list")
Reported-by: Namhyung Kim 
Signed-off-by: Ian Rogers 
Cc: Steinar Gunderson 
Cc: Athira Rajeev 
Cc: Matt Fleming 
Link: https://lore.kernel.org/r/20240703172117.810918-3-irogers@google.com
Signed-off-by: Namhyung Kim

perf tools: Fix a compiler warning of NULL pointer

2024-06-25T18:06:20+00:00

A compiler warning on the second argument of bsearch() should not be
NULL, but there's a case we might pass it.  Let's return early if we
don't have any DSOs to search in __dsos__find_by_longname_id().

  util/dsos.c:184:8: runtime error: null pointer passed as argument 2, which is declared to never be null

Reported-by: kernel test robot 
Reviewed-by: Kan Liang 
Closes: https://lore.kernel.org/oe-lkp/202406180932.84be448c-oliver.sang@intel.com
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240621170528.608772-4-namhyung@kernel.org

tools/perf: Use is_perf_pid_map_name helper function to check dso's of pattern /tmp/perf-%d.map

2024-06-25T18:01:34+00:00

commit 80d496be89ed ("perf report: Add support for profiling JIT
generated code") added support for profiling JIT generated code.
This patch handles dso's of form "/tmp/perf-$PID.map".

Some of the references doesn't check exactly for same pattern.
some uses "if (!strncmp(dso_name, "/tmp/perf-", 10))". Fix
this by using helper function perf_pid_map_tid and
is_perf_pid_map_name which looks for proper pattern of
form: "/tmp/perf-$PID.map" for these checks.

Signed-off-by: Athira Rajeev 
Reviewed-by: Adrian Hunter 
Cc: akanksha@linux.ibm.com
Cc: kjain@linux.ibm.com
Cc: maddy@linux.ibm.com
Cc: disgoel@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240623064850.83720-2-atrajeev@linux.vnet.ibm.com

perf dso: Add reference count checking and accessor functions

2024-05-06T18:28:49+00:00

Add reference count checking to struct dso, this can help with
implementing correct reference counting discipline. To avoid
RC_CHK_ACCESS everywhere, add accessor functions for the variables in
struct dso.

The majority of the change is mechanical in nature and not easy to
split up.

Committer testing:

'perf test' up to this patch shows no regressions.

But:

  util/symbol.c: In function ‘dso__load_bfd_symbols’:
  util/symbol.c:1683:9: error: too few arguments to function ‘dso__set_adjust_symbols’
   1683 |         dso__set_adjust_symbols(dso);
        |         ^~~~~~~~~~~~~~~~~~~~~~~
  In file included from util/symbol.c:21:
  util/dso.h:268:20: note: declared here
    268 | static inline void dso__set_adjust_symbols(struct dso *dso, bool val)
        |                    ^~~~~~~~~~~~~~~~~~~~~~~
  make[6]: *** [/home/acme/git/perf-tools-next/tools/build/Makefile.build:106: /tmp/tmp.ZWHbQftdN6/util/symbol.o] Error 1
    MKDIR   /tmp/tmp.ZWHbQftdN6/tests/workloads/
  make[6]: *** Waiting for unfinished jobs....

This was updated:

  -       symbols__fixup_end(&dso->symbols, false);
  -       symbols__fixup_duplicate(&dso->symbols);
  -       dso->adjust_symbols = 1;
  +       symbols__fixup_end(dso__symbols(dso), false);
  +       symbols__fixup_duplicate(dso__symbols(dso));
  +       dso__set_adjust_symbols(dso);

But not build tested with BUILD_NONDISTRO and libbfd devel files installed
(binutils-devel on fedora).

Add the missing argument:

   	symbols__fixup_end(dso__symbols(dso), false);
   	symbols__fixup_duplicate(dso__symbols(dso));
  -	dso__set_adjust_symbols(dso);
  +	dso__set_adjust_symbols(dso, true);

Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ahelenia Ziemiańska 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Ben Gainey 
Cc: Changbin Du 
Cc: Chengen Du 
Cc: Colin Ian King 
Cc: Dima Kogan 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Thomas Richter 
Cc: Tiezhu Yang 
Cc: Yanteng Si 
Cc: zhaimingbing 
Link: https://lore.kernel.org/r/20240504213803.218974-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dsos: Switch hand crafted code to bsearch()

2024-05-06T13:41:32+00:00

Switch to using the bsearch library function rather than having a hand
written binary search. Const-ify some static functions to avoid compiler
warnings.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Ahelenia Ziemiańska 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Ben Gainey 
Cc: Changbin Du 
Cc: Chengen Du 
Cc: Colin Ian King 
Cc: Dima Kogan 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Thomas Richter 
Cc: Tiezhu Yang 
Cc: Yanteng Si 
Cc: zhaimingbing 
Link: https://lore.kernel.org/r/20240504213803.218974-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dsos: Remove dsosfindnew_link_by_longname_id()

2024-05-06T12:33:37+00:00

Function was only called in dsos.c with the dso parameter as
NULL. Remove the function and specialize for the dso being NULL case
removing other unused functions along the way.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Ahelenia Ziemiańska 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Ben Gainey 
Cc: Changbin Du 
Cc: Chengen Du 
Cc: Colin Ian King 
Cc: Dima Kogan 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Thomas Richter 
Cc: Tiezhu Yang 
Cc: Yanteng Si 
Cc: zhaimingbing 
Link: https://lore.kernel.org/r/20240504213803.218974-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dsos: Remove dsosaddnew()

2024-05-06T12:33:05+00:00

Function no longer used so remove.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Ahelenia Ziemiańska 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Ben Gainey 
Cc: Changbin Du 
Cc: Chengen Du 
Cc: Colin Ian King 
Cc: Dima Kogan 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Thomas Richter 
Cc: Tiezhu Yang 
Cc: Yanteng Si 
Cc: zhaimingbing 
Link: https://lore.kernel.org/r/20240504213803.218974-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dsos: Switch backing storage to array from rbtree/list

2024-05-06T12:13:11+00:00

DSOs were held on a list for fast iteration and in an rbtree for fast
finds.

Switch to using a lazily sorted array where iteration is just iterating
through the array and binary searches are the same complexity as
searching the rbtree.

The find may need to sort the array first which does increase the
complexity, but add operations have lower complexity and overall the
complexity should remain about the same.

The set name operations on the dso just records that the array is no
longer sorted, avoiding complexity in rebalancing the rbtree.

Tighter locking discipline is enforced to avoid the array being resorted
while long and short names or ids are changed.

The array is smaller in size, replacing 6 pointers with 2, and so even
with extra allocated space in the array, the array may be 50%
unoccupied, the memory saving should be at least 2x.

Committer testing:

On a previous version of this patchset we were getting a lot of warnings
about deleting a DSO still on a list, now it is ok:

  root@x1:~# perf probe -l
  root@x1:~# perf probe finish_task_switch
  Added new event:
    probe:finish_task_switch (on finish_task_switch)

  You can now use it in all perf tools, such as:

  	perf record -e probe:finish_task_switch -aR sleep 1

  root@x1:~# perf probe -l
    probe:finish_task_switch (on finish_task_switch@kernel/sched/core.c)
  root@x1:~# perf trace -e probe:finish_task_switch/max-stack=8/ --max-events=1
       0.000 migration/0/19 probe:finish_task_switch(__probe_ip: -1894408688)
                                         finish_task_switch.isra.0 ([kernel.kallsyms])
                                         __schedule ([kernel.kallsyms])
                                         schedule ([kernel.kallsyms])
                                         smpboot_thread_fn ([kernel.kallsyms])
                                         kthread ([kernel.kallsyms])
                                         ret_from_fork ([kernel.kallsyms])
                                         ret_from_fork_asm ([kernel.kallsyms])
  root@x1:~#
  root@x1:~# perf probe -d probe:*
  Removed event: probe:finish_task_switch
  root@x1:~# perf probe -l
  root@x1:~#

I also ran the full 'perf test' suite after applying this one, no
regressions.

Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ahelenia Ziemiańska 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Ben Gainey 
Cc: Changbin Du 
Cc: Chengen Du 
Cc: Colin Ian King 
Cc: Dima Kogan 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Thomas Richter 
Cc: Tiezhu Yang 
Cc: Yanteng Si 
Cc: zhaimingbing 
Link: https://lore.kernel.org/r/20240504213803.218974-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf dsos: Switch more loops to dsos__for_each_dso()

2024-04-12T15:04:13+00:00

Switch loops within dsos.c, add a version that isn't locked. Switch
some unlocked loops to hold the read lock.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Anne Macedo 
Cc: Athira Rajeev 
Cc: Ben Gainey 
Cc: Changbin Du 
Cc: Chengen Du 
Cc: Colin Ian King 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Mark Rutland 
Cc: Markus Elfring 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Thomas Richter 
Cc: Yang Jihong 
Cc: Yanteng Si 
Cc: Yicong Yang 
Cc: zhaimingbing 
Link: https://lore.kernel.org/r/20240410064214.2755936-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo