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| author | Dmitry Vyukov <dvyukov@google.com> | 2020-01-31 07:17:35 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-01-31 19:30:41 +0100 |
| commit | 43e76af85fa7e75ac9b71fc2fcc250abb1889bff (patch) | |
| tree | 6358b0f2cc3a12f9eebd30a1aabb527592cac666 /kernel/Makefile | |
| parent | include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_at... (diff) | |
| download | linux-43e76af85fa7e75ac9b71fc2fcc250abb1889bff.tar.xz linux-43e76af85fa7e75ac9b71fc2fcc250abb1889bff.zip | |
kcov: ignore fault-inject and stacktrace
Don't instrument 3 more files that contain debugging facilities and
produce large amounts of uninteresting coverage for every syscall.
The following snippets are sprinkled all over the place in kcov traces
in a debugging kernel. We already try to disable instrumentation of
stack unwinding code and of most debug facilities. I guess we did not
use fault-inject.c at the time, and stacktrace.c was somehow missed (or
something has changed in kernel/configs). This change both speeds up
kcov (kernel doesn't need to store these PCs, user-space doesn't need to
process them) and frees trace buffer capacity for more useful coverage.
should_fail
lib/fault-inject.c:149
fail_dump
lib/fault-inject.c:45
stack_trace_save
kernel/stacktrace.c:124
stack_trace_consume_entry
kernel/stacktrace.c:86
stack_trace_consume_entry
kernel/stacktrace.c:89
... a hundred frames skipped ...
stack_trace_consume_entry
kernel/stacktrace.c:93
stack_trace_consume_entry
kernel/stacktrace.c:86
Link: http://lkml.kernel.org/r/20200116111449.217744-1-dvyukov@gmail.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/Makefile')
| -rw-r--r-- | kernel/Makefile | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index f2cc0d118a0b..4cb4130ced32 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -27,6 +27,7 @@ KCOV_INSTRUMENT_softirq.o := n # and produce insane amounts of uninteresting coverage. KCOV_INSTRUMENT_module.o := n KCOV_INSTRUMENT_extable.o := n +KCOV_INSTRUMENT_stacktrace.o := n # Don't self-instrument. KCOV_INSTRUMENT_kcov.o := n KASAN_SANITIZE_kcov.o := n |