Steven Rostedt (VMware) 726b3d3f14 ftrace: Handle tracing when switching between context ... When an interrupt or NMI comes in and switches the context, there's a delay from when the preempt_count() shows the update. As the preempt_count() is used to detect recursion having each context have its own bit get set when tracing starts, and if that bit is already set, it is considered a recursion and the function exits. But if this happens in that section where context has changed but preempt_count() has not been updated, this will be incorrectly flagged as a recursion. To handle this case, create another bit call TRANSITION and test it if the current context bit is already set. Flag the call as a recursion if the TRANSITION bit is already set, and if not, set it and continue. The TRANSITION bit will be cleared normally on the return of the function that set it, or if the current context bit is clear, set it and clear the TRANSITION bit to allow for another transition between the current context and an even higher one. Cc: stable@vger.kernel.org Fixes: edc15cafcb ("tracing: Avoid unnecessary multiple recursion checks") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>		2020-11-02 08:52:18 -05:00
..
blktrace.c	block: add a bdget_part helper	2020-10-05 10:38:33 -06:00
bpf_trace.c	networking changes for the 5.10 merge window	2020-10-15 18:42:13 -07:00
bpf_trace.h
fgraph.c
ftrace_internal.h
ftrace.c	Updates for tracing and bootconfig:	2020-10-15 15:51:28 -07:00
Kconfig
kprobe_event_gen_test.c
Makefile
power-traces.c
preemptirq_delay_test.c
ring_buffer_benchmark.c
ring_buffer.c	ring-buffer: Update the description for ring_buffer_wait	2020-10-22 11:26:26 -04:00
rpm-traces.c
synth_event_gen_test.c	tracing: Add support for dynamic strings to synthetic events	2020-10-05 19:32:18 -04:00
trace_benchmark.c
trace_benchmark.h
trace_boot.c	tracing/boot: Add ftrace.instance.*.alloc_snapshot option	2020-10-15 12:01:13 -04:00
trace_branch.c
trace_clock.c
trace_dynevent.c
trace_dynevent.h
trace_entries.h
trace_event_perf.c
trace_events_filter_test.h
trace_events_filter.c
trace_events_hist.c	tracing: Check return value of __create_val_fields() before using its result	2020-10-15 12:00:59 -04:00
trace_events_inject.c
trace_events_synth.c	tracing, synthetic events: Replace buggy strcat() with seq_buf operations	2020-10-27 09:25:36 -04:00
trace_events_trigger.c
trace_events.c	Tracing: Fix mismatch section of adding early trace events	2020-10-16 14:56:52 -07:00
trace_export.c	treewide: Convert macro and uses of __section(foo) to __section("foo")	2020-10-25 14:51:49 -07:00
trace_functions_graph.c
trace_functions.c
trace_hwlat.c
trace_irqsoff.c
trace_kdb.c
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_kprobe.c
trace_mmiotrace.c
trace_nop.c
trace_output.c
trace_output.h
trace_preemptirq.c
trace_printk.c	Updates for tracing and bootconfig:	2020-10-15 15:51:28 -07:00
trace_probe_tmpl.h
trace_probe.c
trace_probe.h	tracing: Move is_good_name() from trace_probe.h to trace.h	2020-10-15 12:01:13 -04:00
trace_sched_switch.c
trace_sched_wakeup.c
trace_selftest_dynamic.c
trace_selftest.c	ftrace: Handle tracing when switching between context	2020-11-02 08:52:18 -05:00
trace_seq.c
trace_stack.c
trace_stat.c
trace_stat.h
trace_synth.h	tracing: Add support for dynamic strings to synthetic events	2020-10-05 19:32:18 -04:00
trace_syscalls.c
trace_uprobe.c
trace.c	tracing: Fix out of bounds write in get_trace_buf	2020-11-02 08:52:18 -05:00
trace.h	ftrace: Handle tracing when switching between context	2020-11-02 08:52:18 -05:00
tracing_map.c
tracing_map.h