[v5,1/1] devtools: add tracepoint check in checkpatch

Message ID 20230307120514.2774917-2-adwivedi@marvell.com (mailing list archive)
State Superseded
Delegated to: Thomas Monjalon
Headers
Series devtools: add tracepoint check in checkpatch |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/loongarch-compilation success Compilation OK
ci/loongarch-unit-testing success Unit Testing PASS
ci/Intel-compilation success Compilation OK
ci/intel-Testing success Testing PASS
ci/github-robot: build success github build: passed
ci/intel-Functional success Functional PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-aarch64-unit-testing success Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-aarch64-compile-testing success Testing PASS
ci/iol-x86_64-compile-testing success Testing PASS
ci/iol-testing success Testing PASS
ci/iol-x86_64-unit-testing success Testing PASS
ci/iol-abi-testing success Testing PASS

Commit Message

Ankur Dwivedi March 7, 2023, 12:05 p.m. UTC
  This patch adds a validation in checkpatch tool, to check if a
tracepoint is present in any new function added in cryptodev, ethdev,
eventdev and mempool library.

In this patch, the build_map_changes function is copied from
check-symbol-change.sh to check-tracepoint.sh. The check-tracepoint.sh
script uses build_map_changes function to create a map of functions.
In the map, the newly added functions, added in the experimental section
are identified and their definition are checked for the presence of
tracepoint. The checkpatch return error if the tracepoint is not present.

For functions for which trace is not needed, they can be added to
devtools/trace-skiplist.txt file. The above tracepoint check will be
skipped for them.

Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
---
 devtools/check-tracepoint.sh | 223 +++++++++++++++++++++++++++++++++++
 devtools/checkpatches.sh     |   9 ++
 devtools/trace-skiplist.txt  |   0
 3 files changed, 232 insertions(+)
 create mode 100755 devtools/check-tracepoint.sh
 create mode 100644 devtools/trace-skiplist.txt
  

Comments

Ankur Dwivedi May 18, 2023, 1:45 p.m. UTC | #1
Hi Thomas,

Please let me know if there is any feedback on this patch.

Regards,
Ankur

>-----Original Message-----
>From: Ankur Dwivedi <adwivedi@marvell.com>
>Sent: Tuesday, March 7, 2023 5:35 PM
>To: dev@dpdk.org
>Cc: thomas@monjalon.net; Jerin Jacob Kollanukkaran <jerinj@marvell.com>;
>Ankur Dwivedi <adwivedi@marvell.com>
>Subject: [PATCH v5 1/1] devtools: add tracepoint check in checkpatch
>
>This patch adds a validation in checkpatch tool, to check if a tracepoint is
>present in any new function added in cryptodev, ethdev, eventdev and
>mempool library.
>
>In this patch, the build_map_changes function is copied from check-symbol-
>change.sh to check-tracepoint.sh. The check-tracepoint.sh script uses
>build_map_changes function to create a map of functions.
>In the map, the newly added functions, added in the experimental section are
>identified and their definition are checked for the presence of tracepoint. The
>checkpatch return error if the tracepoint is not present.
>
>For functions for which trace is not needed, they can be added to
>devtools/trace-skiplist.txt file. The above tracepoint check will be skipped for
>them.
>
>Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
>---
> devtools/check-tracepoint.sh | 223 +++++++++++++++++++++++++++++++++++
> devtools/checkpatches.sh     |   9 ++
> devtools/trace-skiplist.txt  |   0
> 3 files changed, 232 insertions(+)
> create mode 100755 devtools/check-tracepoint.sh  create mode 100644
>devtools/trace-skiplist.txt
>
>diff --git a/devtools/check-tracepoint.sh b/devtools/check-tracepoint.sh new
>file mode 100755 index 0000000000..88d6b1fd53
>--- /dev/null
>+++ b/devtools/check-tracepoint.sh
>@@ -0,0 +1,223 @@
>+#!/bin/sh
>+# SPDX-License-Identifier: BSD-3-Clause # Copyright(c) 2018 Neil Horman
>+<nhorman@tuxdriver.com> # Copyright(C) 2023 Marvell.
>+
>+selfdir=$(dirname $(readlink -f $0))
>+
>+# Library for trace check
>+libdir="cryptodev ethdev eventdev mempool"
>+
>+# Functions for which the trace check can be skipped
>+skiplist="$selfdir/trace-skiplist.txt"
>+
>+build_map_changes()
>+{
>+	local fname="$1"
>+	local mapdb="$2"
>+
>+	cat "$fname" | awk '
>+		# Initialize our variables
>+		BEGIN {map="";sym="";ar="";sec=""; in_sec=0; in_map=0}
>+
>+		# Anything that starts with + or -, followed by an a
>+		# and ends in the string .map is the name of our map file
>+		# This may appear multiple times in a patch if multiple
>+		# map files are altered, and all section/symbol names
>+		# appearing between a triggering of this rule and the
>+		# next trigger of this rule are associated with this file
>+		/[-+] [ab]\/.*\.map/ {map=$2; in_map=1; next}
>+
>+		# The previous rule catches all .map files, anything else
>+		# indicates we left the map chunk.
>+		/[-+] [ab]\// {in_map=0}
>+
>+		# Triggering this rule, which starts a line and ends it
>+		# with a { identifies a versioned section.  The section name is
>+		# the rest of the line with the + and { symbols removed.
>+		# Triggering this rule sets in_sec to 1, which actives the
>+		# symbol rule below
>+		/^.*{/ {
>+			gsub("+", "");
>+			if (in_map == 1) {
>+				sec=$(NF-1); in_sec=1;
>+			}
>+		}
>+
>+		# This rule identifies the end of a section, and disables the
>+		# symbol rule
>+		/.*}/ {in_sec=0}
>+
>+		# This rule matches on a + followed by any characters except a
>:
>+		# (which denotes a global vs local segment), and ends with a ;.
>+		# The semicolon is removed and the symbol is printed with its
>+		# association file name and version section, along with an
>+		# indicator that the symbol is a new addition.  Note this rule
>+		# only works if we have found a version section in the rule
>+		# above (hence the in_sec check) And found a map file (the
>+		# in_map check).  If we are not in a map chunk, do nothing.  If
>+		# we are in a map chunk but not a section chunk, record it as
>+		# unknown.
>+		/^+[^}].*[^:*];/ {gsub(";","");sym=$2;
>+			if (in_map == 1) {
>+				if (in_sec == 1) {
>+					print map " " sym " " sec " add"
>+				} else {
>+					print map " " sym " unknown add"
>+				}
>+			}
>+		}
>+
>+		# This is the same rule as above, but the rule matches on a
>+		# leading - rather than a +, denoting that the symbol is being
>+		# removed.
>+		/^-[^}].*[^:*];/ {gsub(";","");sym=$2;
>+			if (in_map == 1) {
>+				if (in_sec == 1) {
>+					print map " " sym " " sec " del"
>+				} else {
>+					print map " " sym " unknown del"
>+				}
>+			}
>+		}' > "$mapdb"
>+
>+		sort -u "$mapdb" > "$mapdb.2"
>+		mv -f "$mapdb.2" "$mapdb"
>+
>+}
>+
>+find_trace_fn()
>+{
>+	local fname="$1"
>+
>+	cat "$fname" | awk -v symname="$2 *\\\(" '
>+		# Initialize the variables.
>+		# The variable symname provides a pattern to match
>+		# "function_name(", zero or more spaces can be present
>+		# between function_name and (.
>+		BEGIN {state=0; ln_pth=0}
>+
>+		# Matches the function name, set state=1.
>+		$0 ~ symname {state=1}
>+
>+		# If closing parentheses with semicolon ");" is found, then it
>+		# is not the function definition.
>+		/) *;/ {
>+			if (state == 1) {
>+				state=0
>+			}
>+		}
>+
>+		/)/ {
>+			if (state == 1) {
>+				state=2
>+				ln_pth=NR
>+				next
>+			}
>+		}
>+
>+		# If closing parentheses and then opening braces is found in
>+		# adjacent line, then this is the start of function
>+		# definition. Check for tracepoint in the function definition.
>+		# The tracepoint has _trace_ in its name.
>+		/{/ {
>+			if (state == 2) {
>+				if (ln_pth != NR - 1) {
>+					state=0
>+					next
>+				}
>+				while (index($0, "}") != 2) {
>+					if (index($0, "_trace_") != 0) {
>+						exit 0
>+					}
>+					if (getline <= 0) {
>+						break
>+					}
>+				}
>+				exit 1
>+			}
>+		}
>+	'
>+}
>+
>+check_for_tracepoint()
>+{
>+	local patch="$1"
>+	local mapdb="$2"
>+	local skip_sym
>+	local libname
>+	local secname
>+	local mname
>+	local ret=0
>+	local pdir
>+	local libp
>+	local libn
>+	local sym
>+	local ar
>+
>+	while read -r mname symname secname ar; do
>+		pdir=$(echo $mname | awk 'BEGIN {FS="/"};{print $2}')
>+		libname=$(echo $mname | awk 'BEGIN {FS="/"};{print $3}')
>+		skip_sym=0
>+		libp=0
>+
>+		if [ "$pdir" != "lib" ]; then
>+			continue
>+		fi
>+
>+		for libn in $libdir; do
>+			if [ $libn = $libname ]; then
>+				libp=1
>+				break
>+			fi
>+		done
>+
>+		if [ $libp -eq 0 ]; then
>+			continue
>+		fi
>+
>+		for sym in $(cat $skiplist); do
>+			if [ $sym = $symname ]; then
>+				skip_sym=1
>+				break
>+			fi
>+		done
>+
>+		if [ $skip_sym -eq 1 ]; then
>+			continue
>+		fi
>+
>+		if [ "$ar" = "add" ] && [ "$secname" = "EXPERIMENTAL" ]; then
>+			# Check if new API is added with tracepoint
>+			find_trace_fn $patch $symname
>+			if [ $? -eq 1 ]; then
>+				ret=1
>+				echo -n "ERROR: New function $symname is
>added "
>+				echo -n "without a tracepoint. Please add a
>tracepoint "
>+				echo -n "or add the function $symname in "
>+				echo "devtools/trace-skiplist.txt to skip this
>error."
>+			fi
>+		fi
>+	done < "$mapdb"
>+
>+	return $ret
>+}
>+
>+trap clean_and_exit_on_sig EXIT
>+
>+mapfile=`mktemp -t dpdk.mapdb.XXXXXX`
>+patch=$1
>+exit_code=1
>+
>+clean_and_exit_on_sig()
>+{
>+	rm -f "$mapfile"
>+	exit $exit_code
>+}
>+
>+build_map_changes "$patch" "$mapfile"
>+check_for_tracepoint "$patch" "$mapfile"
>+exit_code=$?
>+rm -f "$mapfile"
>+
>+exit $exit_code
>diff --git a/devtools/checkpatches.sh b/devtools/checkpatches.sh index
>1dee094c7a..471db1d21b 100755
>--- a/devtools/checkpatches.sh
>+++ b/devtools/checkpatches.sh
>@@ -10,6 +10,7 @@
> . $(dirname $(readlink -f $0))/load-devel-config
>
> VALIDATE_NEW_API=$(dirname $(readlink -f $0))/check-symbol-change.sh
>+VALIDATE_TRACEPOINT=$(dirname $(readlink -f $0))/check-tracepoint.sh
>
> # Enable codespell by default. This can be overwritten from a config file.
> # Codespell can also be enabled by setting DPDK_CHECKPATCH_CODESPELL to
>a valid path @@ -386,6 +387,14 @@ check () { # <patch-file> <commit>
> 		ret=1
> 	fi
>
>+	! $verbose || printf '\nChecking API additions with tracepoint :\n'
>+	report=$($VALIDATE_TRACEPOINT "$tmpinput")
>+	if [ $? -ne 0 ] ; then
>+		$headline_printed || print_headline "$subject"
>+		printf '%s\n' "$report"
>+		ret=1
>+	fi
>+
> 	if [ "$tmpinput" != "$1" ]; then
> 		rm -f "$tmpinput"
> 		trap - INT
>diff --git a/devtools/trace-skiplist.txt b/devtools/trace-skiplist.txt new file
>mode 100644 index 0000000000..e69de29bb2
>--
>2.25.1
  
Stephen Hemminger May 18, 2023, 3:33 p.m. UTC | #2
On Thu, 18 May 2023 13:45:29 +0000
Ankur Dwivedi <adwivedi@marvell.com> wrote:

> >-----Original Message-----
> >From: Ankur Dwivedi <adwivedi@marvell.com>
> >Sent: Tuesday, March 7, 2023 5:35 PM
> >To: dev@dpdk.org
> >Cc: thomas@monjalon.net; Jerin Jacob Kollanukkaran <jerinj@marvell.com>;
> >Ankur Dwivedi <adwivedi@marvell.com>
> >Subject: [PATCH v5 1/1] devtools: add tracepoint check in checkpatch
> >
> >This patch adds a validation in checkpatch tool, to check if a tracepoint is
> >present in any new function added in cryptodev, ethdev, eventdev and
> >mempool library.
> >
> >In this patch, the build_map_changes function is copied from check-symbol-
> >change.sh to check-tracepoint.sh. The check-tracepoint.sh script uses
> >build_map_changes function to create a map of functions.
> >In the map, the newly added functions, added in the experimental section are
> >identified and their definition are checked for the presence of tracepoint. The
> >checkpatch return error if the tracepoint is not present.
> >
> >For functions for which trace is not needed, they can be added to
> >devtools/trace-skiplist.txt file. The above tracepoint check will be skipped for
> >them.
> >
> >Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>

Given the amount of string processing, it would be more readable in python.
That is not a show stopper, just a suggestion.
  
Ankur Dwivedi Aug. 21, 2023, 1:53 p.m. UTC | #3
>-----Original Message-----
>From: Stephen Hemminger <stephen@networkplumber.org>
>Sent: Thursday, May 18, 2023 9:04 PM
>To: Ankur Dwivedi <adwivedi@marvell.com>
>Cc: Thomas Monjalon <thomas@monjalon.net>; Jerin Jacob Kollanukkaran
><jerinj@marvell.com>; dev@dpdk.org
>Subject: [EXT] Re: [PATCH v5 1/1] devtools: add tracepoint check in checkpatch
>
>External Email
>
>----------------------------------------------------------------------
>On Thu, 18 May 2023 13:45:29 +0000
>Ankur Dwivedi <adwivedi@marvell.com> wrote:
>
>> >-----Original Message-----
>> >From: Ankur Dwivedi <adwivedi@marvell.com>
>> >Sent: Tuesday, March 7, 2023 5:35 PM
>> >To: dev@dpdk.org
>> >Cc: thomas@monjalon.net; Jerin Jacob Kollanukkaran
>> ><jerinj@marvell.com>; Ankur Dwivedi <adwivedi@marvell.com>
>> >Subject: [PATCH v5 1/1] devtools: add tracepoint check in checkpatch
>> >
>> >This patch adds a validation in checkpatch tool, to check if a
>> >tracepoint is present in any new function added in cryptodev, ethdev,
>> >eventdev and mempool library.
>> >
>> >In this patch, the build_map_changes function is copied from
>> >check-symbol- change.sh to check-tracepoint.sh. The
>> >check-tracepoint.sh script uses build_map_changes function to create a
>map of functions.
>> >In the map, the newly added functions, added in the experimental
>> >section are identified and their definition are checked for the
>> >presence of tracepoint. The checkpatch return error if the tracepoint is not
>present.
>> >
>> >For functions for which trace is not needed, they can be added to
>> >devtools/trace-skiplist.txt file. The above tracepoint check will be
>> >skipped for them.
>> >
>> >Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
>
>Given the amount of string processing, it would be more readable in python.
>That is not a show stopper, just a suggestion.

Hi Thomas,

Please let me know if the shell script in this patch is fine or would a python implementation would be more preferable.

Regards,
Ankur
  
Morten Brørup Aug. 21, 2023, 2:46 p.m. UTC | #4
> From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
> Sent: Monday, 21 August 2023 15.54
> 
> >From: Stephen Hemminger <stephen@networkplumber.org>
> >Sent: Thursday, May 18, 2023 9:04 PM
> >
> >----------------------------------------------------------------------
> >On Thu, 18 May 2023 13:45:29 +0000
> >Ankur Dwivedi <adwivedi@marvell.com> wrote:
> >
> >> >From: Ankur Dwivedi <adwivedi@marvell.com>
> >> >Sent: Tuesday, March 7, 2023 5:35 PM
> >> >
> >> >This patch adds a validation in checkpatch tool, to check if a
> >> >tracepoint is present in any new function added in cryptodev,
> ethdev,
> >> >eventdev and mempool library.
> >> >
> >> >In this patch, the build_map_changes function is copied from
> >> >check-symbol- change.sh to check-tracepoint.sh. The
> >> >check-tracepoint.sh script uses build_map_changes function to create
> a
> >map of functions.
> >> >In the map, the newly added functions, added in the experimental
> >> >section are identified and their definition are checked for the
> >> >presence of tracepoint. The checkpatch return error if the
> tracepoint is not
> >present.
> >> >
> >> >For functions for which trace is not needed, they can be added to
> >> >devtools/trace-skiplist.txt file. The above tracepoint check will be
> >> >skipped for them.
> >> >
> >> >Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
> >
> >Given the amount of string processing, it would be more readable in
> python.
> >That is not a show stopper, just a suggestion.
> 
> Hi Thomas,
> 
> Please let me know if the shell script in this patch is fine or would a
> python implementation would be more preferable.
> 
> Regards,
> Ankur

The bigger question is: Do we really want to change tracepoints in functions from opt-in to opt-out?

In my opinion, opt-in for trace is more appropriate.

Nonetheless, having a tool to check for tracepoint presence might still be useful for library reviewers and maintainers. And such a tool might be useful for any library, not just the few libraries suggested by this patch.
  
Thomas Monjalon Aug. 30, 2023, 4:23 p.m. UTC | #5
21/08/2023 16:46, Morten Brørup:
> > From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
> > Sent: Monday, 21 August 2023 15.54
> > 
> > >From: Stephen Hemminger <stephen@networkplumber.org>
> > >Sent: Thursday, May 18, 2023 9:04 PM
> > >
> > >----------------------------------------------------------------------
> > >On Thu, 18 May 2023 13:45:29 +0000
> > >Ankur Dwivedi <adwivedi@marvell.com> wrote:
> > >
> > >> >From: Ankur Dwivedi <adwivedi@marvell.com>
> > >> >Sent: Tuesday, March 7, 2023 5:35 PM
> > >> >
> > >> >This patch adds a validation in checkpatch tool, to check if a
> > >> >tracepoint is present in any new function added in cryptodev,
> > ethdev,
> > >> >eventdev and mempool library.
> > >> >
> > >> >In this patch, the build_map_changes function is copied from
> > >> >check-symbol- change.sh to check-tracepoint.sh. The
> > >> >check-tracepoint.sh script uses build_map_changes function to create
> > a
> > >map of functions.
> > >> >In the map, the newly added functions, added in the experimental
> > >> >section are identified and their definition are checked for the
> > >> >presence of tracepoint. The checkpatch return error if the
> > tracepoint is not
> > >present.
> > >> >
> > >> >For functions for which trace is not needed, they can be added to
> > >> >devtools/trace-skiplist.txt file. The above tracepoint check will be
> > >> >skipped for them.
> > >> >
> > >> >Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
> > >
> > >Given the amount of string processing, it would be more readable in
> > python.
> > >That is not a show stopper, just a suggestion.
> > 
> > Hi Thomas,
> > 
> > Please let me know if the shell script in this patch is fine or would a
> > python implementation would be more preferable.

In general, I wonder how much the check is useful compared to the complexity.


> The bigger question is: Do we really want to change tracepoints in functions from opt-in to opt-out?

Yes that's the question: should traces be mandatory in some libs?

> In my opinion, opt-in for trace is more appropriate.

There was some work to add traces everywhere in few libs, so why not maintaining this state?
I don't really like adding a skip list as one more burden for future authors.


> Nonetheless, having a tool to check for tracepoint presence might still be useful for library reviewers and maintainers. And such a tool might be useful for any library, not just the few libraries suggested by this patch.
  
Morten Brørup Aug. 30, 2023, 6:38 p.m. UTC | #6
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> Sent: Wednesday, 30 August 2023 18.24
> 
> 21/08/2023 16:46, Morten Brørup:
> > > From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
> > > Sent: Monday, 21 August 2023 15.54
> > >
> > > >From: Stephen Hemminger <stephen@networkplumber.org>
> > > >Sent: Thursday, May 18, 2023 9:04 PM
> > > >
> > > >-------------------------------------------------------------------
> ---
> > > >On Thu, 18 May 2023 13:45:29 +0000
> > > >Ankur Dwivedi <adwivedi@marvell.com> wrote:
> > > >
> > > >> >From: Ankur Dwivedi <adwivedi@marvell.com>
> > > >> >Sent: Tuesday, March 7, 2023 5:35 PM
> > > >> >
> > > >> >This patch adds a validation in checkpatch tool, to check if a
> > > >> >tracepoint is present in any new function added in cryptodev,
> > > ethdev,
> > > >> >eventdev and mempool library.
> > > >> >
> > > >> >In this patch, the build_map_changes function is copied from
> > > >> >check-symbol- change.sh to check-tracepoint.sh. The
> > > >> >check-tracepoint.sh script uses build_map_changes function to
> create
> > > a
> > > >map of functions.
> > > >> >In the map, the newly added functions, added in the experimental
> > > >> >section are identified and their definition are checked for the
> > > >> >presence of tracepoint. The checkpatch return error if the
> > > tracepoint is not
> > > >present.
> > > >> >
> > > >> >For functions for which trace is not needed, they can be added
> to
> > > >> >devtools/trace-skiplist.txt file. The above tracepoint check
> will be
> > > >> >skipped for them.
> > > >> >
> > > >> >Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
> > > >
> > > >Given the amount of string processing, it would be more readable in
> > > python.
> > > >That is not a show stopper, just a suggestion.
> > >
> > > Hi Thomas,
> > >
> > > Please let me know if the shell script in this patch is fine or
> would a
> > > python implementation would be more preferable.
> 
> In general, I wonder how much the check is useful compared to the
> complexity.
> 
> 
> > The bigger question is: Do we really want to change tracepoints in
> functions from opt-in to opt-out?
> 
> Yes that's the question: should traces be mandatory in some libs?
> 
> > In my opinion, opt-in for trace is more appropriate.
> 
> There was some work to add traces everywhere in few libs, so why not
> maintaining this state?

I still think it's a silly and burdening requirement, but I'm not against it for the libs where it is already a de facto standard.

<irony>
I can imagine similar requirements regarding logging, telemetry and dump functions being imposed on select libs.

Perhaps we should also require that new libs implement all four types of instrumentation, to ensure that only high quality (i.e. fully instrumented) libs are accepted into DPDK.
</irony>

> I don't really like adding a skip list as one more burden for future
> authors.

If the warning omitted from checkpatches refers to the skip list and its location, it is relatively easy for developers to manage.

And reviewers will notice if new functions have been added to the skip list, indicating that trace has been omitted. So there are also advantages to the skip list.

> 
> 
> > Nonetheless, having a tool to check for tracepoint presence might
> still be useful for library reviewers and maintainers. And such a tool
> might be useful for any library, not just the few libraries suggested by
> this patch.
> 
> 
>
  
Jerin Jacob Sept. 1, 2023, 2:32 a.m. UTC | #7
On Thu, Aug 31, 2023 at 12:08 AM Morten Brørup <mb@smartsharesystems.com> wrote:
>
> > From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > Sent: Wednesday, 30 August 2023 18.24
> >
> > 21/08/2023 16:46, Morten Brørup:
> > > > From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
> > > > Sent: Monday, 21 August 2023 15.54

> >
> > In general, I wonder how much the check is useful compared to the
> > complexity.
> >
> >
> > > The bigger question is: Do we really want to change tracepoints in
> > functions from opt-in to opt-out?
> >
> > Yes that's the question: should traces be mandatory in some libs?
> >
> > > In my opinion, opt-in for trace is more appropriate.
> >
> > There was some work to add traces everywhere in few libs, so why not
> > maintaining this state?
>
> I still think it's a silly and burdening requirement, but I'm not against it for the libs where it is already a de facto standard.
>
> <irony>
> I can imagine similar requirements regarding logging, telemetry and dump functions being imposed on select libs.
>
> Perhaps we should also require that new libs implement all four types of instrumentation, to ensure that only high quality (i.e. fully instrumented) libs are accepted into DPDK.

IMO, There is a lot of effort to put trace points to existing
libraries, without these check, soon the disparity shows up when
someone adds new APIs to library and forget
to add trace points.

It is pretty easy to add trace point and there are a lot of
references, so I don't think there is burden  for a developer
comparing to the effort of adding a new API.

Most of the time, contributors forgets to add trace point because
there is no automatic way to find it.
Also, additional git commits are needs if some decide to add it later.

No strong opinion, If not find not useful, we could mark this patch is
not appliable. Keeping the patch is limbo state is the issue. It is
already reached to v5.
So please decide one way or another.




> </irony>
>
> > I don't really like adding a skip list as one more burden for future
> > authors.
>
> If the warning omitted from checkpatches refers to the skip list and its location, it is relatively easy for developers to manage.
>
> And reviewers will notice if new functions have been added to the skip list, indicating that trace has been omitted. So there are also advantages to the skip list.
>
  
Thomas Monjalon Sept. 1, 2023, 7:28 a.m. UTC | #8
Let's decide in a techboard meeting whether traces are mandatory or not.


01/09/2023 04:32, Jerin Jacob:
> On Thu, Aug 31, 2023 at 12:08 AM Morten Brørup <mb@smartsharesystems.com> wrote:
> >
> > > From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > > Sent: Wednesday, 30 August 2023 18.24
> > >
> > > 21/08/2023 16:46, Morten Brørup:
> > > > > From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
> > > > > Sent: Monday, 21 August 2023 15.54
> 
> > >
> > > In general, I wonder how much the check is useful compared to the
> > > complexity.
> > >
> > >
> > > > The bigger question is: Do we really want to change tracepoints in
> > > functions from opt-in to opt-out?
> > >
> > > Yes that's the question: should traces be mandatory in some libs?
> > >
> > > > In my opinion, opt-in for trace is more appropriate.
> > >
> > > There was some work to add traces everywhere in few libs, so why not
> > > maintaining this state?
> >
> > I still think it's a silly and burdening requirement, but I'm not against it for the libs where it is already a de facto standard.
> >
> > <irony>
> > I can imagine similar requirements regarding logging, telemetry and dump functions being imposed on select libs.
> >
> > Perhaps we should also require that new libs implement all four types of instrumentation, to ensure that only high quality (i.e. fully instrumented) libs are accepted into DPDK.
> 
> IMO, There is a lot of effort to put trace points to existing
> libraries, without these check, soon the disparity shows up when
> someone adds new APIs to library and forget
> to add trace points.
> 
> It is pretty easy to add trace point and there are a lot of
> references, so I don't think there is burden  for a developer
> comparing to the effort of adding a new API.
> 
> Most of the time, contributors forgets to add trace point because
> there is no automatic way to find it.
> Also, additional git commits are needs if some decide to add it later.
> 
> No strong opinion, If not find not useful, we could mark this patch is
> not appliable. Keeping the patch is limbo state is the issue. It is
> already reached to v5.
> So please decide one way or another.
> 
> 
> 
> 
> > </irony>
> >
> > > I don't really like adding a skip list as one more burden for future
> > > authors.
> >
> > If the warning omitted from checkpatches refers to the skip list and its location, it is relatively easy for developers to manage.
> >
> > And reviewers will notice if new functions have been added to the skip list, indicating that trace has been omitted. So there are also advantages to the skip list.
  
Ankur Dwivedi Nov. 14, 2023, 1:15 p.m. UTC | #9
>-----Original Message-----
>From: Thomas Monjalon <thomas@monjalon.net>
>Sent: Friday, September 1, 2023 12:59 PM
>To: Morten Brørup <mb@smartsharesystems.com>; Jerin Jacob
><jerinjacobk@gmail.com>
>Cc: Ankur Dwivedi <adwivedi@marvell.com>; Stephen Hemminger
><stephen@networkplumber.org>; Jerin Jacob Kollanukkaran
><jerinj@marvell.com>; dev@dpdk.org; techboard@dpdk.org
>Subject: Re: [EXT] Re: [PATCH v5 1/1] devtools: add tracepoint check in
>checkpatch
>
>Let's decide in a techboard meeting whether traces are mandatory or not.

It was agreed in techboard meeting in September, that tracepoints needs to be present for new public API functions in cryptodev, ethdev, eventdev, mempool. Can this patch which automates the check for presence of tracepoint be reviewed and merged if its fine?
>
>
>01/09/2023 04:32, Jerin Jacob:
>> On Thu, Aug 31, 2023 at 12:08 AM Morten Brørup
><mb@smartsharesystems.com> wrote:
>> >
>> > > From: Thomas Monjalon [mailto:thomas@monjalon.net]
>> > > Sent: Wednesday, 30 August 2023 18.24
>> > >
>> > > 21/08/2023 16:46, Morten Brørup:
>> > > > > From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
>> > > > > Sent: Monday, 21 August 2023 15.54
>>
>> > >
>> > > In general, I wonder how much the check is useful compared to the
>> > > complexity.
>> > >
>> > >
>> > > > The bigger question is: Do we really want to change tracepoints
>> > > > in
>> > > functions from opt-in to opt-out?
>> > >
>> > > Yes that's the question: should traces be mandatory in some libs?
>> > >
>> > > > In my opinion, opt-in for trace is more appropriate.
>> > >
>> > > There was some work to add traces everywhere in few libs, so why
>> > > not maintaining this state?
>> >
>> > I still think it's a silly and burdening requirement, but I'm not against it for
>the libs where it is already a de facto standard.
>> >
>> > <irony>
>> > I can imagine similar requirements regarding logging, telemetry and dump
>functions being imposed on select libs.
>> >
>> > Perhaps we should also require that new libs implement all four types of
>instrumentation, to ensure that only high quality (i.e. fully instrumented) libs
>are accepted into DPDK.
>>
>> IMO, There is a lot of effort to put trace points to existing
>> libraries, without these check, soon the disparity shows up when
>> someone adds new APIs to library and forget to add trace points.
>>
>> It is pretty easy to add trace point and there are a lot of
>> references, so I don't think there is burden  for a developer
>> comparing to the effort of adding a new API.
>>
>> Most of the time, contributors forgets to add trace point because
>> there is no automatic way to find it.
>> Also, additional git commits are needs if some decide to add it later.
>>
>> No strong opinion, If not find not useful, we could mark this patch is
>> not appliable. Keeping the patch is limbo state is the issue. It is
>> already reached to v5.
>> So please decide one way or another.
>>
>>
>>
>>
>> > </irony>
>> >
>> > > I don't really like adding a skip list as one more burden for
>> > > future authors.
>> >
>> > If the warning omitted from checkpatches refers to the skip list and its
>location, it is relatively easy for developers to manage.
>> >
>> > And reviewers will notice if new functions have been added to the skip list,
>indicating that trace has been omitted. So there are also advantages to the
>skip list.
>
>
>
  

Patch

diff --git a/devtools/check-tracepoint.sh b/devtools/check-tracepoint.sh
new file mode 100755
index 0000000000..88d6b1fd53
--- /dev/null
+++ b/devtools/check-tracepoint.sh
@@ -0,0 +1,223 @@ 
+#!/bin/sh
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2018 Neil Horman <nhorman@tuxdriver.com>
+# Copyright(C) 2023 Marvell.
+
+selfdir=$(dirname $(readlink -f $0))
+
+# Library for trace check
+libdir="cryptodev ethdev eventdev mempool"
+
+# Functions for which the trace check can be skipped
+skiplist="$selfdir/trace-skiplist.txt"
+
+build_map_changes()
+{
+	local fname="$1"
+	local mapdb="$2"
+
+	cat "$fname" | awk '
+		# Initialize our variables
+		BEGIN {map="";sym="";ar="";sec=""; in_sec=0; in_map=0}
+
+		# Anything that starts with + or -, followed by an a
+		# and ends in the string .map is the name of our map file
+		# This may appear multiple times in a patch if multiple
+		# map files are altered, and all section/symbol names
+		# appearing between a triggering of this rule and the
+		# next trigger of this rule are associated with this file
+		/[-+] [ab]\/.*\.map/ {map=$2; in_map=1; next}
+
+		# The previous rule catches all .map files, anything else
+		# indicates we left the map chunk.
+		/[-+] [ab]\// {in_map=0}
+
+		# Triggering this rule, which starts a line and ends it
+		# with a { identifies a versioned section.  The section name is
+		# the rest of the line with the + and { symbols removed.
+		# Triggering this rule sets in_sec to 1, which actives the
+		# symbol rule below
+		/^.*{/ {
+			gsub("+", "");
+			if (in_map == 1) {
+				sec=$(NF-1); in_sec=1;
+			}
+		}
+
+		# This rule identifies the end of a section, and disables the
+		# symbol rule
+		/.*}/ {in_sec=0}
+
+		# This rule matches on a + followed by any characters except a :
+		# (which denotes a global vs local segment), and ends with a ;.
+		# The semicolon is removed and the symbol is printed with its
+		# association file name and version section, along with an
+		# indicator that the symbol is a new addition.  Note this rule
+		# only works if we have found a version section in the rule
+		# above (hence the in_sec check) And found a map file (the
+		# in_map check).  If we are not in a map chunk, do nothing.  If
+		# we are in a map chunk but not a section chunk, record it as
+		# unknown.
+		/^+[^}].*[^:*];/ {gsub(";","");sym=$2;
+			if (in_map == 1) {
+				if (in_sec == 1) {
+					print map " " sym " " sec " add"
+				} else {
+					print map " " sym " unknown add"
+				}
+			}
+		}
+
+		# This is the same rule as above, but the rule matches on a
+		# leading - rather than a +, denoting that the symbol is being
+		# removed.
+		/^-[^}].*[^:*];/ {gsub(";","");sym=$2;
+			if (in_map == 1) {
+				if (in_sec == 1) {
+					print map " " sym " " sec " del"
+				} else {
+					print map " " sym " unknown del"
+				}
+			}
+		}' > "$mapdb"
+
+		sort -u "$mapdb" > "$mapdb.2"
+		mv -f "$mapdb.2" "$mapdb"
+
+}
+
+find_trace_fn()
+{
+	local fname="$1"
+
+	cat "$fname" | awk -v symname="$2 *\\\(" '
+		# Initialize the variables.
+		# The variable symname provides a pattern to match
+		# "function_name(", zero or more spaces can be present
+		# between function_name and (.
+		BEGIN {state=0; ln_pth=0}
+
+		# Matches the function name, set state=1.
+		$0 ~ symname {state=1}
+
+		# If closing parentheses with semicolon ");" is found, then it
+		# is not the function definition.
+		/) *;/ {
+			if (state == 1) {
+				state=0
+			}
+		}
+
+		/)/ {
+			if (state == 1) {
+				state=2
+				ln_pth=NR
+				next
+			}
+		}
+
+		# If closing parentheses and then opening braces is found in
+		# adjacent line, then this is the start of function
+		# definition. Check for tracepoint in the function definition.
+		# The tracepoint has _trace_ in its name.
+		/{/ {
+			if (state == 2) {
+				if (ln_pth != NR - 1) {
+					state=0
+					next
+				}
+				while (index($0, "}") != 2) {
+					if (index($0, "_trace_") != 0) {
+						exit 0
+					}
+					if (getline <= 0) {
+						break
+					}
+				}
+				exit 1
+			}
+		}
+	'
+}
+
+check_for_tracepoint()
+{
+	local patch="$1"
+	local mapdb="$2"
+	local skip_sym
+	local libname
+	local secname
+	local mname
+	local ret=0
+	local pdir
+	local libp
+	local libn
+	local sym
+	local ar
+
+	while read -r mname symname secname ar; do
+		pdir=$(echo $mname | awk 'BEGIN {FS="/"};{print $2}')
+		libname=$(echo $mname | awk 'BEGIN {FS="/"};{print $3}')
+		skip_sym=0
+		libp=0
+
+		if [ "$pdir" != "lib" ]; then
+			continue
+		fi
+
+		for libn in $libdir; do
+			if [ $libn = $libname ]; then
+				libp=1
+				break
+			fi
+		done
+
+		if [ $libp -eq 0 ]; then
+			continue
+		fi
+
+		for sym in $(cat $skiplist); do
+			if [ $sym = $symname ]; then
+				skip_sym=1
+				break
+			fi
+		done
+
+		if [ $skip_sym -eq 1 ]; then
+			continue
+		fi
+
+		if [ "$ar" = "add" ] && [ "$secname" = "EXPERIMENTAL" ]; then
+			# Check if new API is added with tracepoint
+			find_trace_fn $patch $symname
+			if [ $? -eq 1 ]; then
+				ret=1
+				echo -n "ERROR: New function $symname is added "
+				echo -n "without a tracepoint. Please add a tracepoint "
+				echo -n "or add the function $symname in "
+				echo "devtools/trace-skiplist.txt to skip this error."
+			fi
+		fi
+	done < "$mapdb"
+
+	return $ret
+}
+
+trap clean_and_exit_on_sig EXIT
+
+mapfile=`mktemp -t dpdk.mapdb.XXXXXX`
+patch=$1
+exit_code=1
+
+clean_and_exit_on_sig()
+{
+	rm -f "$mapfile"
+	exit $exit_code
+}
+
+build_map_changes "$patch" "$mapfile"
+check_for_tracepoint "$patch" "$mapfile"
+exit_code=$?
+rm -f "$mapfile"
+
+exit $exit_code
diff --git a/devtools/checkpatches.sh b/devtools/checkpatches.sh
index 1dee094c7a..471db1d21b 100755
--- a/devtools/checkpatches.sh
+++ b/devtools/checkpatches.sh
@@ -10,6 +10,7 @@ 
 . $(dirname $(readlink -f $0))/load-devel-config
 
 VALIDATE_NEW_API=$(dirname $(readlink -f $0))/check-symbol-change.sh
+VALIDATE_TRACEPOINT=$(dirname $(readlink -f $0))/check-tracepoint.sh
 
 # Enable codespell by default. This can be overwritten from a config file.
 # Codespell can also be enabled by setting DPDK_CHECKPATCH_CODESPELL to a valid path
@@ -386,6 +387,14 @@  check () { # <patch-file> <commit>
 		ret=1
 	fi
 
+	! $verbose || printf '\nChecking API additions with tracepoint :\n'
+	report=$($VALIDATE_TRACEPOINT "$tmpinput")
+	if [ $? -ne 0 ] ; then
+		$headline_printed || print_headline "$subject"
+		printf '%s\n' "$report"
+		ret=1
+	fi
+
 	if [ "$tmpinput" != "$1" ]; then
 		rm -f "$tmpinput"
 		trap - INT
diff --git a/devtools/trace-skiplist.txt b/devtools/trace-skiplist.txt
new file mode 100644
index 0000000000..e69de29bb2