This is based on top of the deferred unwind core patch series:

 https://lore.kernel.org/linux-trace-kernel/20250625225600.555017347@goodmis.org/ 

This series implements the perf interface to use deferred user space stack
tracing. This version fixes a few issues from v10.

Changes since v10: https://lore.kernel.org/linux-trace-kernel/20250614024605.597728558@goodmis.org/

- Rebased on v11 of the core patches

- Added another smp_mb() between the call to perf_event_callchain_deferred()
  and clearing of cpu_unwind->processing.

- Update using the renamed function that was renamed from
  unwind_deferred_trace() to unwind_user_faultable() in the core
  series.

Josh Poimboeuf (5):
      perf: Remove get_perf_callchain() init_nr argument
      perf: Have get_perf_callchain() return NULL if crosstask and user are set
      perf: Simplify get_perf_callchain() user logic
      perf: Skip user unwind if the task is a kernel thread
      perf: Support deferred user callchains

Namhyung Kim (4):
      perf tools: Minimal CALLCHAIN_DEFERRED support
      perf record: Enable defer_callchain for user callchains
      perf script: Display PERF_RECORD_CALLCHAIN_DEFERRED
      perf tools: Merge deferred user callchains

Steven Rostedt (2):
      perf: Use current->flags & PF_KTHREAD instead of current->mm == NULL
      perf: Support deferred user callchains for per CPU events

----
 include/linux/perf_event.h                |  14 +-
 include/uapi/linux/perf_event.h           |  19 +-
 kernel/bpf/stackmap.c                     |   8 +-
 kernel/events/callchain.c                 |  49 ++--
 kernel/events/core.c                      | 426 +++++++++++++++++++++++++++++-
 tools/include/uapi/linux/perf_event.h     |  19 +-
 tools/lib/perf/include/perf/event.h       |   7 +
 tools/perf/Documentation/perf-script.txt  |   5 +
 tools/perf/builtin-script.c               |  92 +++++++
 tools/perf/util/callchain.c               |  24 ++
 tools/perf/util/callchain.h               |   3 +
 tools/perf/util/event.c                   |   1 +
 tools/perf/util/evlist.c                  |   1 +
 tools/perf/util/evlist.h                  |   1 +
 tools/perf/util/evsel.c                   |  39 +++
 tools/perf/util/evsel.h                   |   1 +
 tools/perf/util/machine.c                 |   1 +
 tools/perf/util/perf_event_attr_fprintf.c |   1 +
 tools/perf/util/sample.h                  |   3 +-
 tools/perf/util/session.c                 |  78 ++++++
 tools/perf/util/tool.c                    |   2 +
 tools/perf/util/tool.h                    |   4 +-
 22 files changed, 763 insertions(+), 35 deletions(-)

On Wed, 25 Jun 2025 19:15:41 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> Namhyung Kim (4):
>       perf tools: Minimal CALLCHAIN_DEFERRED support
>       perf record: Enable defer_callchain for user callchains
>       perf script: Display PERF_RECORD_CALLCHAIN_DEFERRED
>       perf tools: Merge deferred user callchains

For some reason, quilt send mail dropped the last two patches.

I'll send them manually.

-- Steve