diff mbox series

[2/2] check: generate gcov code coverage reports at the end of each section

Message ID 169033661141.3222210.14155623533196891003.stgit@frogsfrogsfrogs (mailing list archive)
State New, archived
Headers show
Series fstests: testing improvements | expand

Commit Message

Darrick J. Wong July 26, 2023, 1:56 a.m. UTC 
From: Darrick J. Wong <djwong@kernel.org>

Support collecting kernel code coverage information as reported in
debugfs.  At the start of each section, we reset the gcov counters;
during the section wrapup, we'll collect the kernel gcov data.

If lcov is installed and the kernel source code is available, it will
also generate a nice html report.  If a CLI web browser is available, it
will also format the html report into text for easy grepping.

This requires the test runner to set REPORT_GCOV=1 explicitly and gcov
to be enabled in the kernel.

Cc: tytso@mit.edu
Cc: kent.overstreet@linux.dev
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
 README      |    3 ++
 check       |   18 ++++++++++++
 common/gcov |   87 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 108 insertions(+)
 create mode 100644 common/gcov

Comments

Zorro Lang July 27, 2023, 2:57 p.m. UTC | #1 
On Tue, Jul 25, 2023 at 06:56:51PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> Support collecting kernel code coverage information as reported in
> debugfs.  At the start of each section, we reset the gcov counters;
> during the section wrapup, we'll collect the kernel gcov data.
> 
> If lcov is installed and the kernel source code is available, it will
> also generate a nice html report.  If a CLI web browser is available, it
> will also format the html report into text for easy grepping.
> 
> This requires the test runner to set REPORT_GCOV=1 explicitly and gcov
> to be enabled in the kernel.
> 
> Cc: tytso@mit.edu
> Cc: kent.overstreet@linux.dev
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---

This version looks good to me,

Reviewed-by: Zorro Lang <zlang@redhat.com>

>  README      |    3 ++
>  check       |   18 ++++++++++++
>  common/gcov |   87 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 108 insertions(+)
>  create mode 100644 common/gcov
> 
> 
> diff --git a/README b/README
> index d4ec73d10d..966ec48ed6 100644
> --- a/README
> +++ b/README
> @@ -249,6 +249,9 @@ Kernel/Modules related configuration:
>     to "forever" and we'll wait forever until the module is gone.
>   - Set KCONFIG_PATH to specify your preferred location of kernel config
>     file. The config is used by tests to check if kernel feature is enabled.
> + - Set REPORT_GCOV to a directory path to make lcov and genhtml generate
> +   html reports from any gcov code coverage data collected by the kernel.
> +   If REPORT_GCOV is set to 1, the report will be written to $REPORT_DIR/gcov/.
>  
>  Test control:
>   - Set LOAD_FACTOR to a nonzero positive integer to increase the amount of
> diff --git a/check b/check
> index c02e693642..9741be23c4 100755
> --- a/check
> +++ b/check
> @@ -451,6 +451,11 @@ _global_log() {
>  	fi
>  }
>  
> +if [ -n "$REPORT_GCOV" ]; then
> +	. ./common/gcov
> +	_gcov_check_report_gcov
> +fi
> +
>  _wrapup()
>  {
>  	seq="check"
> @@ -527,6 +532,18 @@ _wrapup()
>  					     "${#bad[*]}" "${#notrun[*]}" \
>  					     "$((sect_stop - sect_start))"
>  		fi
> +
> +		# Generate code coverage report
> +		if [ -n "$REPORT_GCOV" ]; then
> +			# don't trigger multiple times if caller hits ^C
> +			local gcov_report_dir="$REPORT_GCOV"
> +			test "$gcov_report_dir" = "1" && \
> +				gcov_report_dir="$REPORT_DIR/gcov"
> +			unset REPORT_GCOV
> +
> +			_gcov_generate_report "$gcov_report_dir"
> +		fi
> +
>  		needwrap=false
>  	fi
>  
> @@ -801,6 +818,7 @@ function run_section()
>  	  echo "MOUNT_OPTIONS -- `_scratch_mount_options`"
>  	fi
>  	echo
> +	test -n "$REPORT_GCOV" && _gcov_reset
>  	needwrap=true
>  
>  	if [ ! -z "$SCRATCH_DEV" ]; then
> diff --git a/common/gcov b/common/gcov
> new file mode 100644
> index 0000000000..b7e3ed5a93
> --- /dev/null
> +++ b/common/gcov
> @@ -0,0 +1,87 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2023 Oracle.  All Rights Reserved.
> +#
> +# Routines for capturing kernel code coverage reports
> +
> +GCOV_DIR=/sys/kernel/debug/gcov
> +
> +# Find the topmost directories of the .gcno directory hierarchy
> +__gcov_find_topdirs() {
> +	find "${GCOV_DIR}/" -name '*.gcno' -printf '%d|%h\n' | \
> +		sort -g -k 1 | \
> +		uniq | \
> +		$AWK_PROG -F '|' 'BEGIN { x = -1 } { if (x < 0) x = $1; if ($1 == x) printf("%s\n", $2);}'
> +}
> +
> +# Generate lcov html report from kernel gcov data if configured
> +_gcov_generate_report() {
> +	local output_dir="$1"
> +	test -n "${output_dir}" || return
> +
> +	# Kernel support built in?
> +	test -d "$GCOV_DIR" || return
> +
> +	readarray -t gcno_dirs < <(__gcov_find_topdirs)
> +	test "${#gcno_dirs[@]}" -gt 0 || return
> +
> +	mkdir -p "${output_dir}/raw/"
> +
> +	# Collect raw coverage data from the kernel
> +	readarray -t source_dirs < <(find "${GCOV_DIR}/" -mindepth 1 -maxdepth 1 -type d)
> +	for dir in "${source_dirs[@]}"; do
> +		cp -p -R -d -u "${dir}" "${output_dir}/raw/"
> +	done
> +
> +	# If lcov is installed, use it to summarize the gcda data.
> +	# If it is not installed, there's no point in going forward
> +	command -v lcov > /dev/null || return
> +	local lcov=(lcov --exclude 'include*' --capture)
> +	lcov+=(--output-file "${output_dir}/gcov.report")
> +	for d in "${gcno_dirs[@]}"; do
> +		lcov+=(--directory "${d}")
> +	done
> +
> +	# Generate a detailed HTML report from the summary
> +	local gcov_start_time="$(date --date="${fstests_start_time:-now}")"
> +	local genhtml=()
> +	if command -v genhtml > /dev/null; then
> +		genhtml+=(genhtml -o "${output_dir}/" "${output_dir}/gcov.report")
> +		genhtml+=(--title "fstests on $(hostname -s) @ ${gcov_start_time}" --legend)
> +	fi
> +
> +	# Try to convert the HTML report summary as text for easier grepping if
> +	# there's an HTML renderer present
> +	local totext=()
> +	test "${#totext[@]}" -eq 0 && \
> +		command -v lynx &>/dev/null && \
> +		totext=(lynx -dump "${output_dir}/index.html" -width 120 -nonumbers -nolist)
> +	test "${#totext[@]}" -eq 0 && \
> +		command -v links &>/dev/null && \
> +		totext=(links -dump "${output_dir}/index.html" -width 120)
> +	test "${#totext[@]}" -eq 0 && \
> +		command -v elinks &>/dev/null && \
> +		totext=(elinks -dump "${output_dir}/index.html" --dump-width 120 --no-numbering --no-references)
> +
> +	# Analyze kernel data
> +	"${lcov[@]}" > "${output_dir}/gcov.stdout" 2> "${output_dir}/gcov.stderr"
> +	test "${#genhtml[@]}" -ne 0 && \
> +		"${genhtml[@]}" >> "${output_dir}/gcov.stdout" 2>> "${output_dir}/gcov.stderr"
> +	test "${#totext[@]}" -ne 0 && \
> +		"${totext[@]}" > "${output_dir}/index.txt" 2>> "${output_dir}/gcov.stderr"
> +}
> +
> +# Reset gcov usage data
> +_gcov_reset() {
> +	echo 1 > "${GCOV_DIR}/reset"
> +}
> +
> +# If the caller wanted us to capture gcov reports but the kernel doesn't
> +# support it, turn it off.
> +_gcov_check_report_gcov() {
> +	test -z "$REPORT_GCOV" && return 0
> +	test -w "${GCOV_DIR}/reset" && return 0
> +
> +	unset REPORT_GCOV
> +	return 1
> +}
>
diff mbox series

Patch

diff --git a/README b/README
index d4ec73d10d..966ec48ed6 100644
--- a/README
+++ b/README
@@ -249,6 +249,9 @@  Kernel/Modules related configuration:
    to "forever" and we'll wait forever until the module is gone.
  - Set KCONFIG_PATH to specify your preferred location of kernel config
    file. The config is used by tests to check if kernel feature is enabled.
+ - Set REPORT_GCOV to a directory path to make lcov and genhtml generate
+   html reports from any gcov code coverage data collected by the kernel.
+   If REPORT_GCOV is set to 1, the report will be written to $REPORT_DIR/gcov/.
 
 Test control:
  - Set LOAD_FACTOR to a nonzero positive integer to increase the amount of
diff --git a/check b/check
index c02e693642..9741be23c4 100755
--- a/check
+++ b/check
@@ -451,6 +451,11 @@  _global_log() {
 	fi
 }
 
+if [ -n "$REPORT_GCOV" ]; then
+	. ./common/gcov
+	_gcov_check_report_gcov
+fi
+
 _wrapup()
 {
 	seq="check"
@@ -527,6 +532,18 @@  _wrapup()
 					     "${#bad[*]}" "${#notrun[*]}" \
 					     "$((sect_stop - sect_start))"
 		fi
+
+		# Generate code coverage report
+		if [ -n "$REPORT_GCOV" ]; then
+			# don't trigger multiple times if caller hits ^C
+			local gcov_report_dir="$REPORT_GCOV"
+			test "$gcov_report_dir" = "1" && \
+				gcov_report_dir="$REPORT_DIR/gcov"
+			unset REPORT_GCOV
+
+			_gcov_generate_report "$gcov_report_dir"
+		fi
+
 		needwrap=false
 	fi
 
@@ -801,6 +818,7 @@  function run_section()
 	  echo "MOUNT_OPTIONS -- `_scratch_mount_options`"
 	fi
 	echo
+	test -n "$REPORT_GCOV" && _gcov_reset
 	needwrap=true
 
 	if [ ! -z "$SCRATCH_DEV" ]; then
diff --git a/common/gcov b/common/gcov
new file mode 100644
index 0000000000..b7e3ed5a93
--- /dev/null
+++ b/common/gcov
@@ -0,0 +1,87 @@ 
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2023 Oracle.  All Rights Reserved.
+#
+# Routines for capturing kernel code coverage reports
+
+GCOV_DIR=/sys/kernel/debug/gcov
+
+# Find the topmost directories of the .gcno directory hierarchy
+__gcov_find_topdirs() {
+	find "${GCOV_DIR}/" -name '*.gcno' -printf '%d|%h\n' | \
+		sort -g -k 1 | \
+		uniq | \
+		$AWK_PROG -F '|' 'BEGIN { x = -1 } { if (x < 0) x = $1; if ($1 == x) printf("%s\n", $2);}'
+}
+
+# Generate lcov html report from kernel gcov data if configured
+_gcov_generate_report() {
+	local output_dir="$1"
+	test -n "${output_dir}" || return
+
+	# Kernel support built in?
+	test -d "$GCOV_DIR" || return
+
+	readarray -t gcno_dirs < <(__gcov_find_topdirs)
+	test "${#gcno_dirs[@]}" -gt 0 || return
+
+	mkdir -p "${output_dir}/raw/"
+
+	# Collect raw coverage data from the kernel
+	readarray -t source_dirs < <(find "${GCOV_DIR}/" -mindepth 1 -maxdepth 1 -type d)
+	for dir in "${source_dirs[@]}"; do
+		cp -p -R -d -u "${dir}" "${output_dir}/raw/"
+	done
+
+	# If lcov is installed, use it to summarize the gcda data.
+	# If it is not installed, there's no point in going forward
+	command -v lcov > /dev/null || return
+	local lcov=(lcov --exclude 'include*' --capture)
+	lcov+=(--output-file "${output_dir}/gcov.report")
+	for d in "${gcno_dirs[@]}"; do
+		lcov+=(--directory "${d}")
+	done
+
+	# Generate a detailed HTML report from the summary
+	local gcov_start_time="$(date --date="${fstests_start_time:-now}")"
+	local genhtml=()
+	if command -v genhtml > /dev/null; then
+		genhtml+=(genhtml -o "${output_dir}/" "${output_dir}/gcov.report")
+		genhtml+=(--title "fstests on $(hostname -s) @ ${gcov_start_time}" --legend)
+	fi
+
+	# Try to convert the HTML report summary as text for easier grepping if
+	# there's an HTML renderer present
+	local totext=()
+	test "${#totext[@]}" -eq 0 && \
+		command -v lynx &>/dev/null && \
+		totext=(lynx -dump "${output_dir}/index.html" -width 120 -nonumbers -nolist)
+	test "${#totext[@]}" -eq 0 && \
+		command -v links &>/dev/null && \
+		totext=(links -dump "${output_dir}/index.html" -width 120)
+	test "${#totext[@]}" -eq 0 && \
+		command -v elinks &>/dev/null && \
+		totext=(elinks -dump "${output_dir}/index.html" --dump-width 120 --no-numbering --no-references)
+
+	# Analyze kernel data
+	"${lcov[@]}" > "${output_dir}/gcov.stdout" 2> "${output_dir}/gcov.stderr"
+	test "${#genhtml[@]}" -ne 0 && \
+		"${genhtml[@]}" >> "${output_dir}/gcov.stdout" 2>> "${output_dir}/gcov.stderr"
+	test "${#totext[@]}" -ne 0 && \
+		"${totext[@]}" > "${output_dir}/index.txt" 2>> "${output_dir}/gcov.stderr"
+}
+
+# Reset gcov usage data
+_gcov_reset() {
+	echo 1 > "${GCOV_DIR}/reset"
+}
+
+# If the caller wanted us to capture gcov reports but the kernel doesn't
+# support it, turn it off.
+_gcov_check_report_gcov() {
+	test -z "$REPORT_GCOV" && return 0
+	test -w "${GCOV_DIR}/reset" && return 0
+
+	unset REPORT_GCOV
+	return 1
+}