linux-toradex.git/include/trace/perf.h, branch v7.0-rc5

tracing: perf: Have perf tracepoint callbacks always disable preemption

2026-01-30T15:43:35+00:00

In preparation to convert protection of tracepoints from being protected
by a preempt disabled section to being protected by SRCU, have all the
perf callbacks disable preemption as perf expects preemption to be
disabled when processing tracepoints.

While at it, convert the perf system call callback preempt_disable() to a
guard(preempt).

Link: https://lore.kernel.org/all/20250613152218.1924093-1-bigeasy@linutronix.de/
Link: https://patch.msgid.link/20260108220550.2f6638f3@fedora

Cc: Masami Hiramatsu 
Cc: Mark Rutland 
Cc: Mathieu Desnoyers 
Cc: Andrew Morton 
Cc: "Paul E. McKenney" 
Cc: Sebastian Andrzej Siewior 
Cc: Alexei Starovoitov 
Link: https://patch.msgid.link/20260126231256.174621257@kernel.org
Signed-off-by: Steven Rostedt (Google)

tracing/perf: Add might_fault check to syscall probes

2024-10-09T21:09:46+00:00

Add a might_fault() check to validate that the perf sys_enter/sys_exit
probe callbacks are indeed called from a context where page faults can
be handled.

Cc: Michael Jeanson 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Alexei Starovoitov 
Cc: Yonghong Song 
Cc: Paul E. McKenney 
Cc: Ingo Molnar 
Cc: Arnaldo Carvalho de Melo 
Cc: Mark Rutland 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Andrii Nakryiko 
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes 
Link: https://lore.kernel.org/20241009010718.2050182-8-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Steven Rostedt (Google)

tracing/perf: disable preemption in syscall probe

2024-10-09T21:07:25+00:00

In preparation for allowing system call enter/exit instrumentation to
handle page faults, make sure that perf can handle this change by
explicitly disabling preemption within the perf system call tracepoint
probes to respect the current expectations within perf ring buffer code.

This change does not yet allow perf to take page faults per se within
its probe, but allows its existing probes to adapt to the upcoming
change.

Cc: Michael Jeanson 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Alexei Starovoitov 
Cc: Yonghong Song 
Cc: Paul E. McKenney 
Cc: Ingo Molnar 
Cc: Arnaldo Carvalho de Melo 
Cc: Mark Rutland 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Andrii Nakryiko 
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes 
Link: https://lore.kernel.org/20241009010718.2050182-4-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Steven Rostedt (Google)

tracing: Declare system call tracepoints with TRACE_EVENT_SYSCALL

2024-10-09T21:05:54+00:00

In preparation for allowing system call tracepoints to handle page
faults, introduce TRACE_EVENT_SYSCALL to declare the sys_enter/sys_exit
tracepoints.

Move the common code between __DECLARE_TRACE and __DECLARE_TRACE_SYSCALL
into __DECLARE_TRACE_COMMON.

This change is not meant to alter the generated code, and only prepares
the following modifications.

Cc: Michael Jeanson 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Alexei Starovoitov 
Cc: Yonghong Song 
Cc: Paul E. McKenney 
Cc: Ingo Molnar 
Cc: Arnaldo Carvalho de Melo 
Cc: Mark Rutland 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Andrii Nakryiko 
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes 
Link: https://lore.kernel.org/20241009010718.2050182-2-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Steven Rostedt (Google)

perf/tracing: Use stage6 of tracing to not duplicate macros

2023-01-25T15:31:24+00:00

The perf events are created by the same macro magic as tracefs trace
events are. But to hook into perf, it has its own code. It duplicates many
of the same macros as the tracefs macros and this is an issue because it
misses bug fixes as well as any new enhancements that come with the other
trace macros.

As the trace macros have been put into their own staging files, have perf
take advantage of this and use the tracefs stage 6 macros that the "fast
assign" portion of the trace event macro uses.

Link: https://lkml.kernel.org/r/20230124202515.716458410@goodmis.org
Link: https://lore.kernel.org/lkml/1671181385-5719-1-git-send-email-quic_linyyuan@quicinc.com/

Cc: Frederic Weisbecker 
Cc: Arnaldo Carvalho de Melo 
Acked-by: Peter Zijlstra (Intel) 
Reported-by: Linyu Yuan 
Signed-off-by: Steven Rostedt (Google)

tracing: Add __cpumask to denote a trace event field that is a cpumask_t

2022-11-24T00:08:30+00:00

The trace events have a __bitmask field that can be used for anything
that requires bitmasks. Although currently it is only used for CPU
masks, it could be used in the future for any type of bitmasks.

There is some user space tooling that wants to know if a field is a CPU
mask and not just some random unsigned long bitmask. Introduce
"__cpumask()" helper functions that work the same as the current
__bitmask() helpers but displays in the format file:

  field:__data_loc cpumask_t *[] mask;    offset:36;      size:4; signed:0;

Instead of:

  field:__data_loc unsigned long[] mask;  offset:32;      size:4; signed:0;

The main difference is the type. Instead of "unsigned long" it is
"cpumask_t *". Note, this type field needs to be a real type in the
__dynamic_array() logic that both __cpumask and__bitmask use, but the
comparison field requires it to be a scalar type whereas cpumask_t is a
structure (non-scalar). But everything works when making it a pointer.

Valentin added changes to remove the need of passing in "nr_bits" and the
__cpumask will always use nr_cpumask_bits as its size.

Link: https://lkml.kernel.org/r/20221014080456.1d32b989@rorschach.local.home

Requested-by: Valentin Schneider 
Reviewed-by: Valentin Schneider 
Signed-off-by: Valentin Schneider 
Signed-off-by: Steven Rostedt (Google)

tracing: Introduce helpers to safely handle dynamic-sized sockaddrs

2022-02-28T15:26:38+00:00

Enable a struct sockaddr to be stored in a trace record as a
dynamically-sized field. The common cases are AF_INET and AF_INET6
which are different sizes, and are vastly smaller than a struct
sockaddr_storage.

These are safer because, when used properly, the size of the
sockaddr destination field in each trace record is now guaranteed
to be the same as the source address that is being copied into it.

Link: https://lore.kernel.org/all/164182978641.8391.8277203495236105391.stgit@bazille.1015granger.net/
Signed-off-by: Chuck Lever

tracing/perf: Avoid -Warray-bounds warning for __rel_loc macro

2022-01-28T00:15:45+00:00

As done for trace_events.h, also fix the __rel_loc macro in perf.h,
which silences the -Warray-bounds warning:

In file included from ./include/linux/string.h:253,
                 from ./include/linux/bitmap.h:11,
                 from ./include/linux/cpumask.h:12,
                 from ./include/linux/mm_types_task.h:14,
                 from ./include/linux/mm_types.h:5,
                 from ./include/linux/buildid.h:5,
                 from ./include/linux/module.h:14,
                 from samples/trace_events/trace-events-sample.c:2:
In function '__fortify_strcpy',
    inlined from 'perf_trace_foo_rel_loc' at samples/trace_events/./trace-events-sample.h:519:1:
./include/linux/fortify-string.h:47:33: warning: '__builtin_strcpy' offset 12 is out of the bounds [
0, 4] [-Warray-bounds]
   47 | #define __underlying_strcpy     __builtin_strcpy
      |                                 ^
./include/linux/fortify-string.h:445:24: note: in expansion of macro '__underlying_strcpy'
  445 |                 return __underlying_strcpy(p, q);
      |                        ^~~~~~~~~~~~~~~~~~~

Also make __data struct member a proper flexible array to avoid future
problems.

Link: https://lkml.kernel.org/r/20220125220037.2738923-1-keescook@chromium.org

Cc: Steven Rostedt 
Cc: Masami Hiramatsu 
Fixes: 55de2c0b5610c ("tracing: Add '__rel_loc' using trace event macros")
Reported-by: Stephen Rothwell 
Signed-off-by: Kees Cook 
Signed-off-by: Steven Rostedt (Google)

tracing: Add '__rel_loc' using trace event macros

2021-12-06T20:37:21+00:00

Add '__rel_loc' using trace event macros. These macros are usually
not used in the kernel, except for testing purpose.
This also add "rel_" variant of macros for dynamic_array string,
and bitmask.

Link: https://lkml.kernel.org/r/163757342119.510314.816029622439099016.stgit@devnote2

Cc: Beau Belgrave 
Cc: Namhyung Kim 
Cc: Tom Zanussi 
Signed-off-by: Masami Hiramatsu 
Signed-off-by: Steven Rostedt (VMware)

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-04T00:26:51+00:00

Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller