Steven Rostedt (Google) 0a6d7d4541 ftrace: Be more specific about arch impact when function tracer is enabled ... It was brought up that on ARMv7, that because the FUNCTION_TRACER does not use nops to keep function tracing disabled because of the use of a link register, it does have some performance impact. The start of functions when -pg is used to compile the kernel is: push {lr} bl 8010e7c0 <__gnu_mcount_nc> When function tracing is tuned off, it becomes: push {lr} add sp, sp, #4 Which just puts the stack back to its normal location. But these two instructions at the start of every function does incur some overhead. Be more honest in the Kconfig FUNCTION_TRACER description and specify that the overhead being in the noise was x86 specific, but other architectures may vary. Link: https://lore.kernel.org/all/20220705105416.GE5208@pengutronix.de/ Link: https://lkml.kernel.org/r/20220706161231.085a83da@gandalf.local.home Reported-by: Sascha Hauer <sha@pengutronix.de> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>		2022-07-12 16:36:34 -04:00
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Kconfig	ftrace: Be more specific about arch impact when function tracer is enabled	2022-07-12 16:36:34 -04:00
Makefile	tracing: Disable kcov on trace_preemptirq.c	2022-05-26 21:13:00 -04:00
blktrace.c	block: serialize all debugfs operations using q->debugfs_mutex	2022-06-17 07:31:05 -06:00
bpf_trace.c	bpf: Force cookies array to follow symbols sorting	2022-06-16 19:42:21 -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: Resolve symbols with ftrace_lookup_symbols	2022-05-10 14:42:06 -07:00
ftrace.c	ftrace: Keep address offset in ftrace_lookup_symbols	2022-06-16 19:42:21 -07:00
ftrace_internal.h	…
kprobe_event_gen_test.c	…
pid_list.c	tracing: Cleanup double word in comment	2022-04-26 17:58:50 -04:00
pid_list.h	tracing: Create a sparse bitmask for pid filtering	2021-10-05 17:38:45 -04:00
power-traces.c	…
preemptirq_delay_test.c	…
rethook.c	rethook: Reject getting a rethook if RCU is not watching	2022-06-17 21:53:35 +02:00
ring_buffer.c	ring-buffer: Have 32 bit time stamps use all 64 bits	2022-04-27 17:19:30 -04:00
ring_buffer_benchmark.c	…
rpm-traces.c	…
synth_event_gen_test.c	…
trace.c	tracing: Fix sleeping while atomic in kdb ftdump	2022-07-12 16:35:58 -04:00
trace.h	tracing: Have existing event_command.parse() implementations use helpers	2022-04-26 17:58:50 -04:00
trace_benchmark.c	…
trace_benchmark.h	…
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: Use trace_create_file() to simplify creation of tracefs entries	2022-05-26 21:12:52 -04:00
trace_dynevent.h	…
trace_entries.h	…
trace_eprobe.c	tracing: Remove check of list iterator against head past the loop body	2022-04-27 17:19:31 -04:00
trace_event_perf.c	tracing: Show size of requested perf buffer	2021-10-27 12:25:09 -04:00
trace_events.c	tracing updates for 5.19:	2022-05-29 10:31:36 -07:00
trace_events_filter.c	tracing: Fix comments of create_filter()	2022-05-26 21:13:01 -04:00
trace_events_filter_test.h	…
trace_events_hist.c	tracing/histograms: Fix memory leak problem	2022-07-12 16:35:42 -04:00
trace_events_inject.c	tracing: Support __rel_loc relative dynamic data location attribute	2021-12-06 15:37:21 -05:00
trace_events_synth.c	tracing: Fix strncpy warning in trace_events_synth.c	2022-03-11 11:49:24 -05:00
trace_events_trigger.c	tracing: Fix comments for event_trigger_separate_filter()	2022-05-26 22:03:52 -04:00
trace_events_user.c	tracing: mark user_events as BROKEN	2022-04-02 10:32:14 -07:00
trace_export.c	…
trace_functions.c	ftrace: disable preemption when recursion locked	2021-10-27 11:21:49 -04:00
trace_functions_graph.c	tracing: in_irq() cleanup	2021-10-13 18:19:41 -04:00
trace_hwlat.c	trace/hwlat: make use of the helper function kthread_run_on_cpu()	2022-01-15 16:30:24 +02:00
trace_irqsoff.c	…
trace_kdb.c	…
trace_kprobe.c	tracing/kprobes: Check whether get_kretprobe() returns NULL in kretprobe_dispatcher()	2022-06-17 17:40:06 -04:00
trace_kprobe_selftest.c	…
trace_kprobe_selftest.h	…
trace_mmiotrace.c	…
trace_nop.c	…
trace_osnoise.c	tracing updates for 5.19:	2022-05-29 10:31:36 -07:00
trace_output.c	tracing: Remove usage of list iterator after the loop body	2022-04-27 17:19:30 -04:00
trace_output.h	…
trace_preemptirq.c	lockdep: Fix -Wunused-parameter for _THIS_IP_	2022-04-05 10:24:34 +02:00
trace_printk.c	tracing: Disable "other" permission bits in the tracefs files	2021-10-08 18:08:43 -04:00
trace_probe.c	eprobes: Remove redundant event type information	2022-02-25 12:07:01 -05:00
trace_probe.h	eprobes: Remove redundant event type information	2022-02-25 12:07:01 -05:00
trace_probe_tmpl.h	…
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.c	tracing: Reset the function filter after completing trampoline/graph selftest	2022-05-25 16:57:37 -04:00
trace_selftest_dynamic.c	…
trace_seq.c	…
trace_stack.c	tracing: Disable "other" permission bits in the tracefs files	2021-10-08 18:08:43 -04:00
trace_stat.c	tracing: Disable "other" permission bits in the tracefs files	2021-10-08 18:08:43 -04:00
trace_stat.h	…
trace_synth.h	tracing: synth events: increase max fields count	2021-09-08 15:29:16 -04:00
trace_syscalls.c	tracing: Make tp_printk work on syscall tracepoints	2022-04-26 17:58:52 -04:00
trace_uprobe.c	tracing/uprobes: Remove unwanted initialization in __trace_uprobe_create()	2022-06-17 19:12:07 -04:00
tracing_map.c	tracing: Fix tracing_map_sort_entries() kernel-doc comment	2022-04-26 17:58:51 -04:00
tracing_map.h	…