linux/kernel/trace
Beau Belgrave a65442edb4 tracing/user_events: Add auto cleanup and future persist flag
Currently user events need to be manually deleted via the delete IOCTL
call or via the dynamic_events file. Most operators and processes wish
to have these events auto cleanup when they are no longer used by
anything to prevent them piling without manual maintenance. However,
some operators may not want this, such as pre-registering events via the
dynamic_events tracefs file.

Update user_event_put() to attempt an auto delete of the event if it's
the last reference. The auto delete must run in a work queue to ensure
proper behavior of class->reg() invocations that don't expect the call
to go away from underneath them during the unregister. Add work_struct
to user_event struct to ensure we can do this reliably.

Add a persist flag, that is not yet exposed, to ensure we can toggle
between auto-cleanup and leaving the events existing in the future. When
a non-zero flag is seen during register, return -EINVAL to ensure ABI
is clear for the user processes while we work out the best approach for
persistent events.

Link: https://lkml.kernel.org/r/20230614163336.5797-4-beaub@linux.microsoft.com
Link: https://lore.kernel.org/linux-trace-kernel/20230518093600.3f119d68@rorschach.local.home/

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 13:43:27 -04:00
..
rv tracing/tools: Updates for 6.4 2023-04-28 16:11:26 -07:00
blktrace.c block: remove more NULL checks after bdev_get_queue() 2023-02-21 09:23:22 -07:00
bpf_trace.c tracing updates for 6.4: 2023-04-28 15:57:53 -07:00
bpf_trace.h
error_report-traces.c
fgraph.c arm64 fixes for 5.19-rc1: 2022-06-03 14:05:34 -07:00
fprobe.c fprobe: add recursion detection in fprobe_exit_handler 2023-05-18 07:08:01 +09:00
ftrace_internal.h
ftrace.c Minor tracing updates: 2023-05-05 13:11:02 -07:00
Kconfig tracing: Unbreak user events 2023-03-29 06:52:09 -04:00
kprobe_event_gen_test.c tracing: Fix wrong return in kprobe_event_gen_test.c 2023-03-19 12:20:48 -04:00
Makefile rv: Add Runtime Verification (RV) interface 2022-07-30 14:01:28 -04:00
pid_list.c tracing: Cleanup double word in comment 2022-04-26 17:58:50 -04:00
pid_list.h
power-traces.c
preemptirq_delay_test.c
rethook.c rethook: use preempt_{disable, enable}_notrace in rethook_trampoline_handler 2023-05-18 07:08:01 +09:00
ring_buffer_benchmark.c ring_buffer: Remove unused "event" parameter 2022-11-23 19:08:30 -05:00
ring_buffer.c tracing updates for 6.4: 2023-04-28 15:57:53 -07:00
rpm-traces.c
synth_event_gen_test.c tracing: Always use canonical ftrace path 2023-02-18 14:34:09 -05:00
trace_benchmark.c tracing: Add numeric delta time to the trace event benchmark 2022-09-26 13:01:09 -04:00
trace_benchmark.h tracing: Add numeric delta time to the trace event benchmark 2022-09-26 13:01:09 -04:00
trace_boot.c tracing: Initialize integer variable to prevent garbage return value 2022-05-26 21:13:00 -04:00
trace_branch.c
trace_clock.c
trace_dynevent.c tracing: Free buffers when a used dynamic event is removed 2022-11-23 19:07:12 -05:00
trace_dynevent.h
trace_entries.h
trace_eprobe.c kernel/trace: extract common part in process_fetch_insn 2023-02-24 10:04:13 +09:00
trace_event_perf.c tracing/perf: Use strndup_user instead of kzalloc/strncpy_from_user 2022-11-23 19:08:31 -05:00
trace_events_filter_test.h
trace_events_filter.c tracing: Add a way to filter function addresses to function names 2023-01-25 10:31:11 -05:00
trace_events_hist.c tracing: Rename stacktrace field to common_stacktrace 2023-05-23 23:38:23 -04:00
trace_events_inject.c
trace_events_synth.c tracing/synthetic: Make lastcmd_mutex static 2023-04-06 15:08:18 -04:00
trace_events_trigger.c tracing: Do not synchronize freeing of trigger filter on boot up 2022-12-14 08:50:56 -05:00
trace_events_user.c tracing/user_events: Add auto cleanup and future persist flag 2023-06-14 13:43:27 -04:00
trace_events.c tracing: Rename stacktrace field to common_stacktrace 2023-05-23 23:38:23 -04:00
trace_export.c tracing: Fix TASK_COMM_LEN in trace event format file 2023-02-12 10:23:39 -05:00
trace_functions_graph.c
trace_functions.c
trace_hwlat.c tracing/hwlat: Replace sched_setaffinity with set_cpus_allowed_ptr 2023-03-19 13:23:22 -04:00
trace_irqsoff.c
trace_kdb.c
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_kprobe.c kernel/trace: extract common part in process_fetch_insn 2023-02-24 10:04:13 +09:00
trace_mmiotrace.c
trace_nop.c
trace_osnoise.c tracing/timerlat: Always wakeup the timerlat thread 2023-05-23 11:54:31 -04:00
trace_output.c tracing: Modify print_fields() for fields output order 2023-06-14 12:41:52 -04:00
trace_output.h tracing: Add "fields" option to show raw trace event fields 2023-03-29 06:52:08 -04:00
trace_preemptirq.c cpuidle: tracing, preempt: Squash _rcuidle tracing 2023-01-31 15:01:46 +01:00
trace_printk.c
trace_probe_kernel.h kernel/trace: Provide default impelentations defined in trace_probe_tmpl.h 2023-02-24 09:44:27 +09:00
trace_probe_tmpl.h kernel/trace: extract common part in process_fetch_insn 2023-02-24 10:04:13 +09:00
trace_probe.c tracing: Rename kvfree_rcu() to kvfree_rcu_mightsleep() 2023-04-05 13:48:03 +00:00
trace_probe.h kernel/trace: Introduce trace_probe_print_args and use it in *probes 2023-02-24 09:44:15 +09:00
trace_recursion_record.c tracing: Use trace_create_file() to simplify creation of tracefs entries 2022-05-26 21:12:52 -04:00
trace_sched_switch.c sched/tracing: Append prev_state to tp args instead 2022-05-12 00:37:11 +02:00
trace_sched_wakeup.c sched/tracing: Append prev_state to tp args instead 2022-05-12 00:37:11 +02:00
trace_selftest_dynamic.c
trace_selftest.c tracing: Have function_graph selftest call cond_resched() 2023-05-28 21:15:46 -04:00
trace_seq.c tracing: Acquire buffer from temparary trace sequence 2023-02-07 12:42:54 -05:00
trace_stack.c
trace_stat.c
trace_stat.h
trace_synth.h tracing: Allow synthetic events to pass around stacktraces 2023-01-25 10:31:24 -05:00
trace_syscalls.c tracing: Remove unused __bad_type_size() method 2022-11-17 20:21:06 -05:00
trace_uprobe.c kernel/trace: extract common part in process_fetch_insn 2023-02-24 10:04:13 +09:00
trace.c tracing: Only make selftest conditionals affect the global_trace 2023-05-28 21:15:33 -04:00
trace.h tracing: Add "fields" option to show raw trace event fields 2023-03-29 06:52:08 -04:00
tracing_map.c tracing: Remove unused variable 'dups' 2022-10-03 12:20:31 -04:00
tracing_map.h