[PATCH] perf test fix check open filename arg using perf trace on s390x

[PATCH] perf test fix check open filename arg using perf trace on s390x

[Thomas Richter]

This perf test case fails on s390x. The touch command on s390x uses
the openat system call to open the file named on the command line:

[root@s35lp76 perf]# ./perf probe -l
  probe:vfs_getname    (on getname_flags:72@fs/namei.c with pathname)
[root@s35lp76 perf]# ./perf trace -e open touch /tmp/abc
     0.400 ( 0.015 ms): touch/27542 open(filename:
		/usr/lib/locale/locale-archive, flags: CLOEXEC         ) = 3
[root@s35lp76 perf]#

There is no open system call for file /tmp/abc. Instead openat
system call is used:

[root@s35lp76 perf]# strace touch /tmp/abc
    execve("/usr/bin/touch", ["touch", "/tmp/abc"], 0x3ffd547ec98
			/* 30 vars */) = 0
    [...]
    openat(AT_FDCWD, "/tmp/abc", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3
    [...]

On s390x the egrep command does not find a matching pattern and returns
an error.

Fix this for the s390x platform and create a platform dependend command
line to enable the perf probe to listen to openat system call on s390x
and get the correct perf trace output.

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
---
 tools/perf/tests/shell/trace+probe_vfs_getname.sh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/shell/trace+probe_vfs_getname.sh b/tools/perf/tests/shell/trace+probe_vfs_getname.sh
index 2e68c5f120da..2a9ef080efd0 100755
--- a/tools/perf/tests/shell/trace+probe_vfs_getname.sh
+++ b/tools/perf/tests/shell/trace+probe_vfs_getname.sh
@@ -17,8 +17,10 @@ skip_if_no_perf_probe || exit 2
 file=$(mktemp /tmp/temporary_file.XXXXX)
 
 trace_open_vfs_getname() {
-	perf trace -e open touch $file 2>&1 | \
-	egrep " +[0-9]+\.[0-9]+ +\( +[0-9]+\.[0-9]+ ms\): +touch\/[0-9]+ open\(filename: +${file}, +flags: CREAT\|NOCTTY\|NONBLOCK\|WRONLY, +mode: +IRUGO\|IWUGO\) += +[0-9]+$"
+	test "$(uname -m)" = s390x && { svc="openat"; txt="dfd: +CWD, +"; }
+
+	perf trace -e ${svc:-open} touch $file 2>&1 | \
+	egrep " +[0-9]+\.[0-9]+ +\( +[0-9]+\.[0-9]+ ms\): +touch\/[0-9]+ ${svc:-open}\(${txt}filename: +${file}, +flags: CREAT\|NOCTTY\|NONBLOCK\|WRONLY, +mode: +IRUGO\|IWUGO\) += +[0-9]+$"
 }
 
 
-- 
2.13.4

[PATCH] perf test: fix test case probe libc's inet_pton on s390x

[Thomas Richter]

Perf test case probe libc's inet_pton & backtrace it with ping
fails on s390x. The reason is the 'realpath /lib64/ld*.so.* | uniq'
line which returns 2 libraries:

        root@s35lp76 shell]# realpath /lib64/ld*.so.* | uniq
        /usr/lib64/ld-2.26.so
        /usr/lib64/ld_pre_smc.so.1.0.1
        [root@s35lp76 shell]

This output makes the perf probe command lines invalid.

Use tool ldd to find out the libraries required by the bash and
check if symbol inet_pton is part of the libc library.
Some distros do not have a /lib64 directory.

I have also added a check for the existence of an IPv6
network interface before it is being used.

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Suggested-by: Hendrik Brückner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brückner <brueckner@linux.vnet.ibm.com>
---
 tools/perf/tests/shell/trace+probe_libc_inet_pton.sh | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
index 7a84d73324e3..b9c913f1a360 100755
--- a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
+++ b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
@@ -10,8 +10,8 @@
 
 . $(dirname $0)/lib/probe.sh
 
-ld=$(realpath /lib64/ld*.so.* | uniq)
-libc=$(echo $ld | sed 's/ld/libc/g')
+libc=$(ldd $(which bash) 2>/dev/null | fgrep libc | awk '{ print $3 }')
+nm -g $libc 2>/dev/null | fgrep -q inet_pton || exit 254
 
 trace_libc_inet_pton_backtrace() {
 	idx=0
@@ -37,6 +37,9 @@ trace_libc_inet_pton_backtrace() {
 	done
 }
 
+# Check for IPv6 interface existence
+ip a sh lo | fgrep -q inet6 || exit 2
+
 skip_if_no_perf_probe && \
 perf probe -q $libc inet_pton && \
 trace_libc_inet_pton_backtrace
-- 
2.13.4

Re: [PATCH] perf test fix check open filename arg using perf trace on s390x

[Arnaldo Carvalho de Melo]

Em Tue, Nov 14, 2017 at 08:18:46AM +0100, Thomas Richter escreveu:
> This perf test case fails on s390x. The touch command on s390x uses
> the openat system call to open the file named on the command line:

Thanks, tested on x86_64 and applied!

- Arnaldo
 
> [root@s35lp76 perf]# ./perf probe -l
>   probe:vfs_getname    (on getname_flags:72@fs/namei.c with pathname)
> [root@s35lp76 perf]# ./perf trace -e open touch /tmp/abc
>      0.400 ( 0.015 ms): touch/27542 open(filename:
> 		/usr/lib/locale/locale-archive, flags: CLOEXEC         ) = 3
> [root@s35lp76 perf]#
> 
> There is no open system call for file /tmp/abc. Instead openat
> system call is used:
> 
> [root@s35lp76 perf]# strace touch /tmp/abc
>     execve("/usr/bin/touch", ["touch", "/tmp/abc"], 0x3ffd547ec98
> 			/* 30 vars */) = 0
>     [...]
>     openat(AT_FDCWD, "/tmp/abc", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3
>     [...]
> 
> On s390x the egrep command does not find a matching pattern and returns
> an error.
> 
> Fix this for the s390x platform and create a platform dependend command
> line to enable the perf probe to listen to openat system call on s390x
> and get the correct perf trace output.
> 
> Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
> ---
>  tools/perf/tests/shell/trace+probe_vfs_getname.sh | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/tests/shell/trace+probe_vfs_getname.sh b/tools/perf/tests/shell/trace+probe_vfs_getname.sh
> index 2e68c5f120da..2a9ef080efd0 100755
> --- a/tools/perf/tests/shell/trace+probe_vfs_getname.sh
> +++ b/tools/perf/tests/shell/trace+probe_vfs_getname.sh
> @@ -17,8 +17,10 @@ skip_if_no_perf_probe || exit 2
>  file=$(mktemp /tmp/temporary_file.XXXXX)
>  
>  trace_open_vfs_getname() {
> -	perf trace -e open touch $file 2>&1 | \
> -	egrep " +[0-9]+\.[0-9]+ +\( +[0-9]+\.[0-9]+ ms\): +touch\/[0-9]+ open\(filename: +${file}, +flags: CREAT\|NOCTTY\|NONBLOCK\|WRONLY, +mode: +IRUGO\|IWUGO\) += +[0-9]+$"
> +	test "$(uname -m)" = s390x && { svc="openat"; txt="dfd: +CWD, +"; }
> +
> +	perf trace -e ${svc:-open} touch $file 2>&1 | \
> +	egrep " +[0-9]+\.[0-9]+ +\( +[0-9]+\.[0-9]+ ms\): +touch\/[0-9]+ ${svc:-open}\(${txt}filename: +${file}, +flags: CREAT\|NOCTTY\|NONBLOCK\|WRONLY, +mode: +IRUGO\|IWUGO\) += +[0-9]+$"
>  }
>  
>  
> -- 
> 2.13.4

Re: [PATCH] perf test: fix test case probe libc's inet_pton on s390x

[Arnaldo Carvalho de Melo]

Em Tue, Nov 14, 2017 at 08:18:47AM +0100, Thomas Richter escreveu:
> Perf test case probe libc's inet_pton & backtrace it with ping
> fails on s390x. The reason is the 'realpath /lib64/ld*.so.* | uniq'
> line which returns 2 libraries:
> 
>         root@s35lp76 shell]# realpath /lib64/ld*.so.* | uniq
>         /usr/lib64/ld-2.26.so
>         /usr/lib64/ld_pre_smc.so.1.0.1
>         [root@s35lp76 shell]
> 
> This output makes the perf probe command lines invalid.
> 
> Use tool ldd to find out the libraries required by the bash and
> check if symbol inet_pton is part of the libc library.
> Some distros do not have a /lib64 directory.
> 
> I have also added a check for the existence of an IPv6
> network interface before it is being used.
> 
> Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
> Suggested-by: Hendrik Brückner <brueckner@linux.vnet.ibm.com>
> Reviewed-by: Hendrik Brückner <brueckner@linux.vnet.ibm.com>
> ---
>  tools/perf/tests/shell/trace+probe_libc_inet_pton.sh | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> index 7a84d73324e3..b9c913f1a360 100755
> --- a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> +++ b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> @@ -10,8 +10,8 @@
>  
>  . $(dirname $0)/lib/probe.sh
>  
> -ld=$(realpath /lib64/ld*.so.* | uniq)
> -libc=$(echo $ld | sed 's/ld/libc/g')
> +libc=$(ldd $(which bash) 2>/dev/null | fgrep libc | awk '{ print $3 }')
> +nm -g $libc 2>/dev/null | fgrep -q inet_pton || exit 254
>  
>  trace_libc_inet_pton_backtrace() {
>  	idx=0
> @@ -37,6 +37,9 @@ trace_libc_inet_pton_backtrace() {
>  	done
>  }
>  
> +# Check for IPv6 interface existence
> +ip a sh lo | fgrep -q inet6 || exit 2
> +
>  skip_if_no_perf_probe && \
>  perf probe -q $libc inet_pton && \
>  trace_libc_inet_pton_backtrace

Humm, this one is failing:

[root@jouet linux]# ls -ila /usr/lib64/libc-2.25.so 
3151772 -rwxr-xr-x. 2 root root 2163016 Aug 28 11:48 /usr/lib64/libc-2.25.so
[root@jouet linux]# ls -ila /lib64/libc-2.25.so 
3151772 -rwxr-xr-x. 2 root root 2163016 Aug 28 11:48 /lib64/libc-2.25.so
[root@jouet linux]#

[root@jouet linux]# tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
PING ::1(::1) 56 data bytes
64 bytes from ::1: icmp_seq=1 ttl=64 time=0.068 ms
--- ::1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.068/0.068/0.068/0.000 ms
0.000 probe_libc:inet_pton:(7fa97fac3d80))
__GI___inet_pton (/usr/lib64/libc-2.25.so)
FAIL: expected backtrace entry 6 ".*inet_pton[[:space:]]\(/lib64/libc.so.6\)$" got "__GI___inet_pton (/usr/lib64/libc-2.25.so)"
[root@jouet linux]#

[root@jouet linux]# ldd `which ping6` | grep 'libc\>'
	libc.so.6 => /lib64/libc.so.6 (0x00007f883df4f000)
[root@jouet linux]#

[root@jouet linux]# ps | grep bash
 3112 pts/3    00:00:00 bash
[root@jouet linux]# ldd `which bash` | grep 'libc\>'
	libc.so.6 => /lib64/libc.so.6 (0x00007fdd0a17f000)
[root@jouet linux]# grep -w libc /proc/3112/maps 
7f0d017ee000-7f0d019b5000 r-xp 00000000 fd:00 3151772  /usr/lib64/libc-2.25.so
7f0d019b5000-7f0d01bb5000 ---p 001c7000 fd:00 3151772  /usr/lib64/libc-2.25.so
7f0d01bb5000-7f0d01bb9000 r--p 001c7000 fd:00 3151772  /usr/lib64/libc-2.25.so
7f0d01bb9000-7f0d01bbb000 rw-p 001cb000 fd:00 3151772  /usr/lib64/libc-2.25.so
[root@jouet linux]#

/me scratches head

Different name, same contents, need to look at the inode... ;-\

- Arnaldo

Re: [PATCH] perf test: fix test case probe libc's inet_pton on s390x

[Arnaldo Carvalho de Melo]

Em Tue, Nov 14, 2017 at 10:26:25AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Tue, Nov 14, 2017 at 08:18:47AM +0100, Thomas Richter escreveu:
> > -ld=$(realpath /lib64/ld*.so.* | uniq)
> > -libc=$(echo $ld | sed 's/ld/libc/g')
> > +libc=$(ldd $(which bash) 2>/dev/null | fgrep libc | awk '{ print $3 }')
> 
> Humm, this one is failing:
> 
> [root@jouet linux]# ls -ila /usr/lib64/libc-2.25.so 
> 3151772 -rwxr-xr-x. 2 root root 2163016 Aug 28 11:48 /usr/lib64/libc-2.25.so
> [root@jouet linux]# ls -ila /lib64/libc-2.25.so 
> 3151772 -rwxr-xr-x. 2 root root 2163016 Aug 28 11:48 /lib64/libc-2.25.so
> [root@jouet linux]#
> 
> [root@jouet linux]# tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> PING ::1(::1) 56 data bytes
> 64 bytes from ::1: icmp_seq=1 ttl=64 time=0.068 ms
> --- ::1 ping statistics ---
> 1 packets transmitted, 1 received, 0% packet loss, time 0ms
> rtt min/avg/max/mdev = 0.068/0.068/0.068/0.000 ms
> 0.000 probe_libc:inet_pton:(7fa97fac3d80))
> __GI___inet_pton (/usr/lib64/libc-2.25.so)
> FAIL: expected backtrace entry 6 ".*inet_pton[[:space:]]\(/lib64/libc.so.6\)$" got "__GI___inet_pton (/usr/lib64/libc-2.25.so)"
> [root@jouet linux]#
> 
> [root@jouet linux]# ldd `which ping6` | grep 'libc\>'
> 	libc.so.6 => /lib64/libc.so.6 (0x00007f883df4f000)
> [root@jouet linux]#
> 
> [root@jouet linux]# ps | grep bash
>  3112 pts/3    00:00:00 bash
> [root@jouet linux]# ldd `which bash` | grep 'libc\>'
> 	libc.so.6 => /lib64/libc.so.6 (0x00007fdd0a17f000)
> [root@jouet linux]# grep -w libc /proc/3112/maps 
> 7f0d017ee000-7f0d019b5000 r-xp 00000000 fd:00 3151772  /usr/lib64/libc-2.25.so
> 7f0d019b5000-7f0d01bb5000 ---p 001c7000 fd:00 3151772  /usr/lib64/libc-2.25.so
> 7f0d01bb5000-7f0d01bb9000 r--p 001c7000 fd:00 3151772  /usr/lib64/libc-2.25.so
> 7f0d01bb9000-7f0d01bbb000 rw-p 001cb000 fd:00 3151772  /usr/lib64/libc-2.25.so
> [root@jouet linux]#
> 
> /me scratches head
> 
> Different name, same contents, need to look at the inode... ;-\

Nah, lets ask the kernel how is it that it sees libc, please test the
following, works for me:

diff --git a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
index 7a84d73324e3..8b3da21a08f1 100755
--- a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
+++ b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
@@ -10,8 +10,8 @@
 
 . $(dirname $0)/lib/probe.sh
 
-ld=$(realpath /lib64/ld*.so.* | uniq)
-libc=$(echo $ld | sed 's/ld/libc/g')
+libc=$(grep -w libc /proc/self/maps | head -1 | sed -r 's/.*[[:space:]](\/.*)/\1/g')
+nm -g $libc 2>/dev/null | fgrep -q inet_pton || exit 254
 
 trace_libc_inet_pton_backtrace() {
 	idx=0
@@ -37,6 +37,9 @@ trace_libc_inet_pton_backtrace() {
 	done
 }
 
+# Check for IPv6 interface existence
+ip a sh lo | fgrep -q inet6 || exit 2
+
 skip_if_no_perf_probe && \
 perf probe -q $libc inet_pton && \
 trace_libc_inet_pton_backtrace

Re: [PATCH] perf test: fix test case probe libc's inet_pton on s390x

[Arnaldo Carvalho de Melo]

Em Tue, Nov 14, 2017 at 10:34:09AM -0300, Arnaldo Carvalho de Melo escreveu:
> > Different name, same contents, need to look at the inode... ;-\
> 
> Nah, lets ask the kernel how is it that it sees libc, please test the
> following, works for me:

BTW, this is what I sticked on that cset:

    Committer changes:
    
    We can't really use ldd for libc, as in some systems, such as x86_64, it
    has hardlinks and then ldd sees one and the kernel the other, so grep
    for libc in /proc/self/maps to get the one we'll receive from
    PERF_RECORD_MMAP.

- Arnaldo
 
> diff --git a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> index 7a84d73324e3..8b3da21a08f1 100755
> --- a/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> +++ b/tools/perf/tests/shell/trace+probe_libc_inet_pton.sh
> @@ -10,8 +10,8 @@
>  
>  . $(dirname $0)/lib/probe.sh
>  
> -ld=$(realpath /lib64/ld*.so.* | uniq)
> -libc=$(echo $ld | sed 's/ld/libc/g')
> +libc=$(grep -w libc /proc/self/maps | head -1 | sed -r 's/.*[[:space:]](\/.*)/\1/g')
> +nm -g $libc 2>/dev/null | fgrep -q inet_pton || exit 254
>  
>  trace_libc_inet_pton_backtrace() {
>  	idx=0
> @@ -37,6 +37,9 @@ trace_libc_inet_pton_backtrace() {
>  	done
>  }
>  
> +# Check for IPv6 interface existence
> +ip a sh lo | fgrep -q inet6 || exit 2
> +
>  skip_if_no_perf_probe && \
>  perf probe -q $libc inet_pton && \
>  trace_libc_inet_pton_backtrace

Re: [PATCH] perf test: fix test case probe libc's inet_pton on s390x

[Thomas-Mich Richter]

On 11/14/2017 02:47 PM, Arnaldo Carvalho de Melo wrote:
> Em Tue, Nov 14, 2017 at 10:34:09AM -0300, Arnaldo Carvalho de Melo escreveu:
>>> Different name, same contents, need to look at the inode... ;-\
>>
>> Nah, lets ask the kernel how is it that it sees libc, please test the
>> following, works for me:

works for me too.

> 
> BTW, this is what I sticked on that cset:
> 
>     Committer changes:
>     
>     We can't really use ldd for libc, as in some systems, such as x86_64, it
>     has hardlinks and then ldd sees one and the kernel the other, so grep
>     for libc in /proc/self/maps to get the one we'll receive from
>     PERF_RECORD_MMAP.
> 
> - Arnaldo
> 

Yes I am fine with this changes.
Go ahead.

-- 
Thomas Richter, Dept 3303, IBM LTC Boeblingen Germany
--
Vorsitzende des Aufsichtsrats: Martina Koederitz 
Geschäftsführung: Dirk Wittkopp
Sitz der Gesellschaft: Böblingen / Registergericht: Amtsgericht Stuttgart, HRB 243294

Re: [PATCH] perf test: fix test case probe libc's inet_pton on s390x

[Arnaldo Carvalho de Melo]

Em Tue, Nov 14, 2017 at 02:55:48PM +0100, Thomas-Mich Richter escreveu:
> On 11/14/2017 02:47 PM, Arnaldo Carvalho de Melo wrote:
> > Em Tue, Nov 14, 2017 at 10:34:09AM -0300, Arnaldo Carvalho de Melo escreveu:
> >>> Different name, same contents, need to look at the inode... ;-\
> >>
> >> Nah, lets ask the kernel how is it that it sees libc, please test the
> >> following, works for me:
> 
> works for me too.
> 
> > 
> > BTW, this is what I sticked on that cset:
> > 
> >     Committer changes:
> >     
> >     We can't really use ldd for libc, as in some systems, such as x86_64, it
> >     has hardlinks and then ldd sees one and the kernel the other, so grep
> >     for libc in /proc/self/maps to get the one we'll receive from
> >     PERF_RECORD_MMAP.
> > 
> > - Arnaldo
> > 
> 
> Yes I am fine with this changes.
> Go ahead.

Thanks for checking, committed.

- Arnaldo