This is based on top of the deferred unwind core patch series:
https://lore.kernel.org/linux-trace-kernel/20250708012239.268642741@kernel.org/ (local)
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
unwind/core
This series implements the perf interface to use deferred user space stack
tracing.
The code for this series is located here:
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
unwind/perf
Changes since v12: https://lore.kernel.org/linux-trace-kernel/20250701180410.755491417@goodmis.org/ (local)
- Also check against PF_USER_WORKER as io workers do not have PF_KTHREAD
set.
- Removed deferred_request_nmi() and have NMIs just use the normal
deferred_request() function. As Peter Zijlstra has stated, in_nmi() can
nest because some exceptions set in_nmi() and another NMI could come in.
- Removed use of timestamp. The deferred unwind has gone back to using
cookies, and perf doesn't use the cookie. This means the
struct perf_callchain_deferred_event is not modified.
Head SHA1: 3d88d03d533ede8d2d513942e768607aa9279c4b
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|PF_USER_WORKER instead of current->mm == NULL
perf: Support deferred user callchains for per CPU events
----
include/linux/perf_event.h | 13 +-
include/uapi/linux/perf_event.h | 19 +-
kernel/bpf/stackmap.c | 8 +-
kernel/events/callchain.c | 49 ++--
kernel/events/core.c | 407 +++++++++++++++++++++++++++++-
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, 742 insertions(+), 36 deletions(-)