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Revision 511e19b9e2112463c33a744ecb8a798056074408 authored by Namhyung Kim on 19 December 2022, 20:17:30 UTC, committed by Arnaldo Carvalho de Melo on 21 December 2022, 17:52:39 UTC 
perf lock contention: Add -L/--lock-filter option
 
The -L/--lock-filter option is to filter only given locks.  The locks
can be specified by address or name (if exists).

  $ sudo ./perf lock record -a  sleep 1

  $ sudo ./perf lock con -l
   contended  total wait  max wait  avg wait           address  symbol

          57     1.11 ms  42.83 us  19.54 us  ffff9f4140059000
          15   280.88 us  23.51 us  18.73 us  ffffffff9d007a40  jiffies_lock
           1    20.49 us  20.49 us  20.49 us  ffffffff9d0d50c0  rcu_state
           1     9.02 us   9.02 us   9.02 us  ffff9f41759e9ba0

  $ sudo ./perf lock con -L jiffies_lock,rcu_state
   contended  total wait  max wait  avg wait      type  caller

          15   280.88 us  23.51 us  18.73 us  spinlock  tick_sched_do_timer+0x93
           1    20.49 us  20.49 us  20.49 us  spinlock  __softirqentry_text_start+0xeb

  $ sudo ./perf lock con -L ffff9f4140059000
   contended  total wait  max wait  avg wait      type  caller

          38   779.40 us  42.83 us  20.51 us  spinlock  worker_thread+0x50
          11   216.30 us  39.87 us  19.66 us  spinlock  queue_work_on+0x39
           8   118.13 us  20.51 us  14.77 us  spinlock  kthread+0xe5

Committer testing:

  # uname -a
  Linux quaco 6.0.12-200.fc36.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Dec 8 17:15:53 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
  # perf lock record
  ^C[ perf record: Woken up 1 times to write data ]
  # perf lock con -L jiffies_lock,rcu_state
   contended   total wait     max wait     avg wait         type   caller

  # perf lock con
   contended   total wait     max wait     avg wait         type   caller

           1      9.06 us      9.06 us      9.06 us     spinlock   call_timer_fn+0x24
  # perf lock con -L call
  ignore unknown symbol: call
   contended   total wait     max wait     avg wait         type   caller

           1      9.06 us      9.06 us      9.06 us     spinlock   call_timer_fn+0x24
  #

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221219201732.460111-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1 parent 529772c
Raw File
test_fortify.sh 
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0-only
set -e

# Argument 1: Source file to build.
IN="$1"
shift
# Extract just the filename for error messages below.
FILE="${IN##*/}"
# Extract the function name for error messages below.
FUNC="${FILE#*-}"
FUNC="${FUNC%%-*}"
FUNC="${FUNC%%.*}"
# Extract the symbol to test for in build/symbol test below.
WANT="__${FILE%%-*}"

# Argument 2: Where to write the build log.
OUT="$1"
shift
TMP="${OUT}.tmp"

# Argument 3: Path to "nm" tool.
NM="$1"
shift

# Remaining arguments are: $(CC) $(c_flags)

# Clean up temporary file at exit.
__cleanup() {
	rm -f "$TMP"
}
trap __cleanup EXIT

# Function names in warnings are wrapped in backticks under UTF-8 locales.
# Run the commands with LANG=C so that grep output will not change.
export LANG=C

status=
# Attempt to build a source that is expected to fail with a specific warning.
if "$@" -Werror -c "$IN" -o "$OUT".o 2> "$TMP" ; then
	# If the build succeeds, either the test has failed or the
	# warning may only happen at link time (Clang). In that case,
	# make sure the expected symbol is unresolved in the symbol list.
	# If so, FORTIFY is working for this case.
	if ! $NM -A "$OUT".o | grep -m1 "\bU ${WANT}$" >>"$TMP" ; then
		status="warning: unsafe ${FUNC}() usage lacked '$WANT' symbol in $IN"
	fi
else
	# If the build failed, check for the warning in the stderr.
	# GCC:
	# ./include/linux/fortify-string.h:316:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
	# Clang 14:
	# ./include/linux/fortify-string.h:316:4: error: call to __write_overflow_field declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning]
	if ! grep -Eq -m1 "error: call to .?\b${WANT}\b.?" "$TMP" ; then
		status="warning: unsafe ${FUNC}() usage lacked '$WANT' warning in $IN"
	fi
fi

if [ -n "$status" ]; then
	# Report on failure results, including compilation warnings.
	echo "$status" | tee "$OUT" >&2
else
	# Report on good results, and save any compilation output to log.
	echo "ok: unsafe ${FUNC}() usage correctly detected with '$WANT' in $IN" >"$OUT"
fi
cat "$TMP" >>"$OUT"
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