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[PATCH v3 1/2] perf trace: Add tests for BTF general augmentation

Howard Chu posted 2 patches 1 year ago
There is a newer version of this series
[PATCH v3 1/2] perf trace: Add tests for BTF general augmentation
Posted by Howard Chu 1 year ago 
Currently, we only have perf trace augmentation tests for enum
arguments. This patch adds tests for more general syscall arguments,
such as struct pointers, strings, and buffers.

These tests utilize the perf config system to configure the perf trace
output, as suggested by Arnaldo Carvalho de Melo <acme@kernel.org>

Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Howard Chu <howardchu95@gmail.com>
---
 tools/perf/tests/shell/trace_btf_general.sh | 93 +++++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100755 tools/perf/tests/shell/trace_btf_general.sh

diff --git a/tools/perf/tests/shell/trace_btf_general.sh b/tools/perf/tests/shell/trace_btf_general.sh
new file mode 100755
index 000000000000..bef07bad42bb
--- /dev/null
+++ b/tools/perf/tests/shell/trace_btf_general.sh
@@ -0,0 +1,93 @@
+#!/bin/bash
+# perf trace BTF general tests
+# SPDX-License-Identifier: GPL-2.0
+
+err=0
+set -e
+
+. "$(dirname $0)"/lib/probe.sh
+
+file1=$(mktemp /tmp/file1_XXXX)
+file2=$(echo $file1 | sed 's/file1/file2/g')
+
+buffer="buffer content"
+perf_config_tmp=$(mktemp /tmp/.perfconfig_XXXXX)
+
+trap cleanup EXIT TERM INT HUP
+
+check_vmlinux() {
+  echo "Checking if vmlinux BTF exists"
+  if ! ls /sys/kernel/btf/vmlinux 1>/dev/null 2>&1
+  then
+    echo "Skipped due to missing vmlinux BTF"
+    err=2
+  fi
+}
+
+trace_test_string() {
+  echo "Testing perf trace's string augmentation"
+  if ! perf trace -e renameat* --max-events=1 -- mv ${file1} ${file2} 2>&1 | \
+    grep -q -E "^mv/[0-9]+ renameat(2)?\(.*, \"${file1}\", .*, \"${file2}\", .*\) += +[0-9]+$"
+  then
+    echo "String augmentation test failed"
+    err=1
+  fi
+}
+
+trace_test_buffer() {
+  echo "Testing perf trace's buffer augmentation"
+  # echo will insert a newline (\10) at the end of the buffer
+  if ! perf trace -e write --max-events=1 -- echo "${buffer}" 2>&1 | \
+    grep -q -E "^echo/[0-9]+ write\([0-9]+, ${buffer}.*, [0-9]+\) += +[0-9]+$"
+  then
+    echo "Buffer augmentation test failed"
+    err=1
+  fi
+}
+
+trace_test_struct_btf() {
+  echo "Testing perf trace's struct augmentation"
+  if ! perf trace -e clock_nanosleep --force-btf --max-events=1 -- sleep 1 2>&1 | \
+    grep -q -E "^sleep/[0-9]+ clock_nanosleep\(0, 0, \{1,\}, 0x[0-9a-f]+\) += +[0-9]+$"
+  then
+    echo "BTF struct augmentation test failed"
+    err=1
+  fi
+}
+
+cleanup() {
+  rm -rf ${file1} ${file2} ${perf_config_tmp}
+}
+
+trap_cleanup() {
+  echo "Unexpected signal in ${FUNCNAME[1]}"
+  cleanup
+  exit 1
+}
+
+# don't overwrite user's perf config
+trace_config() {
+  export PERF_CONFIG=${perf_config_tmp}
+  perf config trace.show_arg_names=false trace.show_duration=false \
+    trace.show_timestamp=false trace.args_alignment=0
+}
+
+skip_if_no_perf_trace || exit 2
+
+check_vmlinux
+
+trace_config
+
+trace_test_string
+
+if [ $err = 0 ]; then
+  trace_test_buffer
+fi
+
+if [ $err = 0 ]; then
+  trace_test_struct_btf
+fi
+
+cleanup
+
+exit $err
-- 
2.43.0
Re: [PATCH v3 1/2] perf trace: Add tests for BTF general augmentation
Posted by Namhyung Kim 1 year ago 
Hi Howard,

On Wed, Dec 11, 2024 at 02:49:26PM -0800, Howard Chu wrote:
> Currently, we only have perf trace augmentation tests for enum
> arguments. This patch adds tests for more general syscall arguments,
> such as struct pointers, strings, and buffers.
> 
> These tests utilize the perf config system to configure the perf trace
> output, as suggested by Arnaldo Carvalho de Melo <acme@kernel.org>
> 
> Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Signed-off-by: Howard Chu <howardchu95@gmail.com>
> ---
>  tools/perf/tests/shell/trace_btf_general.sh | 93 +++++++++++++++++++++
>  1 file changed, 93 insertions(+)
>  create mode 100755 tools/perf/tests/shell/trace_btf_general.sh
> 
> diff --git a/tools/perf/tests/shell/trace_btf_general.sh b/tools/perf/tests/shell/trace_btf_general.sh
> new file mode 100755
> index 000000000000..bef07bad42bb
> --- /dev/null
> +++ b/tools/perf/tests/shell/trace_btf_general.sh
> @@ -0,0 +1,93 @@
> +#!/bin/bash
> +# perf trace BTF general tests
> +# SPDX-License-Identifier: GPL-2.0
> +
> +err=0
> +set -e
> +
> +. "$(dirname $0)"/lib/probe.sh
> +
> +file1=$(mktemp /tmp/file1_XXXX)
> +file2=$(echo $file1 | sed 's/file1/file2/g')
> +
> +buffer="buffer content"
> +perf_config_tmp=$(mktemp /tmp/.perfconfig_XXXXX)
> +
> +trap cleanup EXIT TERM INT HUP
> +
> +check_vmlinux() {
> +  echo "Checking if vmlinux BTF exists"
> +  if ! ls /sys/kernel/btf/vmlinux 1>/dev/null 2>&1

Normally we do

  if [ ! -f /sys/kernel/btf/vmlinux ]

> +  then
> +    echo "Skipped due to missing vmlinux BTF"
> +    err=2

This can be overwritten by trace_test_string.


> +  fi
> +}
> +
> +trace_test_string() {
> +  echo "Testing perf trace's string augmentation"
> +  if ! perf trace -e renameat* --max-events=1 -- mv ${file1} ${file2} 2>&1 | \
> +    grep -q -E "^mv/[0-9]+ renameat(2)?\(.*, \"${file1}\", .*, \"${file2}\", .*\) += +[0-9]+$"

Does this work without BTF support?

Thanks
Namhyung


> +  then
> +    echo "String augmentation test failed"
> +    err=1
> +  fi
> +}
> +
> +trace_test_buffer() {
> +  echo "Testing perf trace's buffer augmentation"
> +  # echo will insert a newline (\10) at the end of the buffer
> +  if ! perf trace -e write --max-events=1 -- echo "${buffer}" 2>&1 | \
> +    grep -q -E "^echo/[0-9]+ write\([0-9]+, ${buffer}.*, [0-9]+\) += +[0-9]+$"
> +  then
> +    echo "Buffer augmentation test failed"
> +    err=1
> +  fi
> +}
> +
> +trace_test_struct_btf() {
> +  echo "Testing perf trace's struct augmentation"
> +  if ! perf trace -e clock_nanosleep --force-btf --max-events=1 -- sleep 1 2>&1 | \
> +    grep -q -E "^sleep/[0-9]+ clock_nanosleep\(0, 0, \{1,\}, 0x[0-9a-f]+\) += +[0-9]+$"
> +  then
> +    echo "BTF struct augmentation test failed"
> +    err=1
> +  fi
> +}
> +
> +cleanup() {
> +  rm -rf ${file1} ${file2} ${perf_config_tmp}
> +}
> +
> +trap_cleanup() {
> +  echo "Unexpected signal in ${FUNCNAME[1]}"
> +  cleanup
> +  exit 1
> +}
> +
> +# don't overwrite user's perf config
> +trace_config() {
> +  export PERF_CONFIG=${perf_config_tmp}
> +  perf config trace.show_arg_names=false trace.show_duration=false \
> +    trace.show_timestamp=false trace.args_alignment=0
> +}
> +
> +skip_if_no_perf_trace || exit 2
> +
> +check_vmlinux
> +
> +trace_config
> +
> +trace_test_string
> +
> +if [ $err = 0 ]; then
> +  trace_test_buffer
> +fi
> +
> +if [ $err = 0 ]; then
> +  trace_test_struct_btf
> +fi
> +
> +cleanup
> +
> +exit $err
> -- 
> 2.43.0
>
Re: [PATCH v3 1/2] perf trace: Add tests for BTF general augmentation
Posted by Howard Chu 12 months ago 
Hello Namhyung,

On Fri, Dec 13, 2024 at 4:42 PM Namhyung Kim <namhyung@kernel.org> wrote:
>
> Hi Howard,
>
> On Wed, Dec 11, 2024 at 02:49:26PM -0800, Howard Chu wrote:
> > Currently, we only have perf trace augmentation tests for enum
> > arguments. This patch adds tests for more general syscall arguments,
> > such as struct pointers, strings, and buffers.
> >
> > These tests utilize the perf config system to configure the perf trace
> > output, as suggested by Arnaldo Carvalho de Melo <acme@kernel.org>
> >
> > Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> > Signed-off-by: Howard Chu <howardchu95@gmail.com>
> > ---
> >  tools/perf/tests/shell/trace_btf_general.sh | 93 +++++++++++++++++++++
> >  1 file changed, 93 insertions(+)
> >  create mode 100755 tools/perf/tests/shell/trace_btf_general.sh
> >
> > diff --git a/tools/perf/tests/shell/trace_btf_general.sh b/tools/perf/tests/shell/trace_btf_general.sh
> > new file mode 100755
> > index 000000000000..bef07bad42bb
> > --- /dev/null
> > +++ b/tools/perf/tests/shell/trace_btf_general.sh
> > @@ -0,0 +1,93 @@
> > +#!/bin/bash
> > +# perf trace BTF general tests
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +err=0
> > +set -e
> > +
> > +. "$(dirname $0)"/lib/probe.sh
> > +
> > +file1=$(mktemp /tmp/file1_XXXX)
> > +file2=$(echo $file1 | sed 's/file1/file2/g')
> > +
> > +buffer="buffer content"
> > +perf_config_tmp=$(mktemp /tmp/.perfconfig_XXXXX)
> > +
> > +trap cleanup EXIT TERM INT HUP
> > +
> > +check_vmlinux() {
> > +  echo "Checking if vmlinux BTF exists"
> > +  if ! ls /sys/kernel/btf/vmlinux 1>/dev/null 2>&1
>
> Normally we do
>
>   if [ ! -f /sys/kernel/btf/vmlinux ]

Sure, I'll change the check to this.

>
> > +  then
> > +    echo "Skipped due to missing vmlinux BTF"
> > +    err=2
>
> This can be overwritten by trace_test_string.

Oops my bad sorry.

>
>
> > +  fi
> > +}
> > +
> > +trace_test_string() {
> > +  echo "Testing perf trace's string augmentation"
> > +  if ! perf trace -e renameat* --max-events=1 -- mv ${file1} ${file2} 2>&1 | \
> > +    grep -q -E "^mv/[0-9]+ renameat(2)?\(.*, \"${file1}\", .*, \"${file2}\", .*\) += +[0-9]+$"
>
> Does this work without BTF support?

Yes, this works without BTF with Arnaldo's patch adding
sys_enter_renameat2. Before the patch, it wouldn't work because the
second filename would not be displayed properly. I understand this may
seem redundant, but now in perf trace all the data is collected
through the BTF general collector (if BTF is present), so this
trace_test_string() tests the new code path that uses BTF information
to pretty-print string arguments, since all data collection goes
through it.

Thanks,
Howard

Patchew 2.1-devel-b67e4c2

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