linux/kernel/trace
Steven Rostedt b6fc31b687 tracing: Add "traceoff" flag to boot time tracing instances
Add a "flags" delimiter (^) to the "trace_instance" kernel command line
parameter, and add the "traceoff" flag. The format is:

   trace_instance=<name>[^<flag1>[^<flag2>]][@<memory>][,<events>]

The code allows for more than one flag to be added, but currently only
"traceoff" is done so.

The motivation for this change came from debugging with the persistent
ring buffer and having trace_printk() writing to it. The trace_printk
calls are always enabled, and the boot after the crash was having the
unwanted trace_printks from the current boot inject into the ring buffer
with the trace_printks of the crash kernel, making the output very
confusing.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineeth Pillai <vineeth@bitbyteword.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Aring <aahringo@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Jonathan Corbet" <corbet@lwn.net>
Link: https://lore.kernel.org/20240823014019.053229958@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-08-26 13:54:08 -04:00
..
rv rv: Update rv_en(dis)able_monitor doc to match kernel-doc 2024-05-21 19:03:35 -04:00
blktrace.c blktrace: convert strncpy() to strscpy_pad() 2024-04-25 21:07:08 -07:00
bpf_trace.c bpf: Change bpf_session_cookie return value to __u64 * 2024-06-21 19:32:36 +02:00
bpf_trace.h tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
error_report-traces.c
fgraph.c function_graph: Fix the ret_stack used by ftrace_graph_ret_addr() 2024-08-07 20:20:30 -04:00
fprobe.c fprobe: Fix to allocate entry_data_size buffer with rethook instances 2024-03-01 09:18:24 +09:00
ftrace_internal.h function_graph: Make fgraph_update_pid_func() a stub for !DYNAMIC_FTRACE 2024-06-10 18:08:23 -04:00
ftrace.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
Kconfig tracing: Build event generation tests only as modules 2024-06-12 08:43:12 +09:00
kprobe_event_gen_test.c
Makefile
pid_list.c trace/pid_list: Change gfp flags in pid_list_fill_irq() 2024-07-15 15:07:14 -04:00
pid_list.h
power-traces.c
preemptirq_delay_test.c minmax: make generic MIN() and MAX() macros available everywhere 2024-07-28 15:49:18 -07:00
rethook.c rethook: honor CONFIG_FTRACE_VALIDATE_RCU_IS_WATCHING in rethook_try_get() 2024-05-01 23:18:48 +09:00
ring_buffer_benchmark.c ring-buffer: Read and write to ring buffers with custom sub buffer size 2023-12-20 07:54:56 -05:00
ring_buffer.c ring-buffer: Align meta-page to sub-buffers for improved TLB usage 2024-08-26 13:42:23 -04:00
rpm-traces.c
synth_event_gen_test.c tracing / synthetic: Disable events after testing in synth_event_gen_test_init() 2023-12-21 10:04:45 -05:00
trace_benchmark.c tracing: Improve benchmark test performance by using do_div() 2024-05-13 20:00:57 -04:00
trace_benchmark.h
trace_boot.c tracing: Allow creating instances with specified system events 2023-12-18 23:14:16 -05:00
trace_branch.c
trace_btf.c tracing/probes: Fix to search structure fields correctly 2024-02-17 21:25:42 +09:00
trace_btf.h
trace_clock.c
trace_dynevent.c
trace_dynevent.h
trace_entries.h
trace_eprobe.c tracing/probes: Support $argN in return probe (kprobe and fprobe) 2024-03-07 00:27:34 +09:00
trace_event_perf.c
trace_events_filter_test.h
trace_events_filter.c
trace_events_hist.c tracing: Have format file honor EVENT_FILE_FL_FREED 2024-08-07 18:12:46 -04:00
trace_events_inject.c tracing: Have format file honor EVENT_FILE_FL_FREED 2024-08-07 18:12:46 -04:00
trace_events_synth.c tracing/synthetic: Fix trace_string() return value 2024-02-15 11:40:01 -05:00
trace_events_trigger.c tracing: Have format file honor EVENT_FILE_FL_FREED 2024-08-07 18:12:46 -04:00
trace_events_user.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
trace_events.c tracing: Use refcount for trace_event_file reference counter 2024-08-07 18:12:46 -04:00
trace_export.c
trace_fprobe.c tracing/probes: support '%pd' type for print struct dentry's name 2024-05-01 23:18:47 +09:00
trace_functions_graph.c tracing/fgraph: Have fgraph handle previous boot function addresses 2024-08-15 08:35:48 -04:00
trace_functions.c ftrace: Hide one more entry in stack trace when ftrace_pid is enabled 2024-06-06 15:22:18 -04:00
trace_hwlat.c
trace_irqsoff.c function_graph: Move set_graph_function tests to shadow stack global var 2024-06-04 10:37:35 -04:00
trace_kdb.c
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_kprobe.c tracing/kprobes: Fix build error when find_module() is not available 2024-07-10 09:47:00 +09:00
trace_mmiotrace.c
trace_nop.c
trace_osnoise.c rtla/osnoise: set the default threshold to 1us 2024-07-01 18:54:31 -04:00
trace_output.c tracing: Add last boot delta offset for stack traces 2024-06-14 12:28:22 -04:00
trace_output.h
trace_preemptirq.c
trace_printk.c
trace_probe_kernel.h
trace_probe_tmpl.h tracing/probes: Support $argN in return probe (kprobe and fprobe) 2024-03-07 00:27:34 +09:00
trace_probe.c tracing/probes: fix error check in parse_btf_field() 2024-05-27 21:32:35 +09:00
trace_probe.h tracing/probes: support '%pd' type for print struct dentry's name 2024-05-01 23:18:47 +09:00
trace_recursion_record.c
trace_sched_switch.c tracing: Move saved_cmdline code into trace_sched_switch.c 2024-03-17 07:58:53 -04:00
trace_sched_wakeup.c function_graph: Move set_graph_function tests to shadow stack global var 2024-06-04 10:37:35 -04:00
trace_selftest_dynamic.c
trace_selftest.c fgraph: Use str_plural() in test_graph_storage_single() 2024-07-01 19:57:51 -04:00
trace_seq.c trace_seq: Increase the buffer size to almost two pages 2023-12-18 23:14:16 -05:00
trace_stack.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
trace_stat.c
trace_stat.h
trace_synth.h
trace_syscalls.c
trace_uprobe.c uprobes: prevent mutex_lock() under rcu_read_lock() 2024-05-24 07:44:44 +09:00
trace.c tracing: Add "traceoff" flag to boot time tracing instances 2024-08-26 13:54:08 -04:00
trace.h Linux 6.11-rc3 2024-08-14 16:59:28 -04:00
tracing_map.c tracing: Fix overflow in get_free_elt() 2024-08-07 20:23:12 -04:00
tracing_map.h