kernel/tools/perf/tests/shell/trace+probe_vfs_getname.sh, branch linux-4.17.y

perf test shell: Fix check open filename arg using 'perf trace'

2017-12-27T15:15:56Z

Commit f231af789b11 ("perf test shell: Fix check open filename arg using 'perf trace' on s390x") added an exception for s390x to use openat() instead of open() in the test that intercepts a open syscall to look for the filename argument as obtained by the vfs_getname 'perf probe' it puts in place at the getname_flags kernel function. Its not just s390x that uses openat() instead of open(), so use 'perf list' to look for the syscall:sys_enter_open(at)? present in the system being tested instead of checking if the system is s390x. In fact Namhyung pointed out that glibc 2.26 changed this behaviour, as described in https://lwn.net/Articles/738694/, so systems where glibc is >= 2.26 will need this patch for this test to work, which already took place in some distros for architectures such as s390x, while Fedora 26 x86_64 is at glibc 2.25, i.e. still uses open(). Signed-off-by: Michael Petlan Tested-by: Arnaldo Carvalho de Melo Tested-by: Thomas Richter Link: https://lkml.kernel.org/r/ab23fe42-1080-a46b-503e-744e097f414f@linux.vnet.ibm.com Cc: Adrian Hunter Cc: David Ahern Cc: Hendrik Brueckner Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan LPU-Reference: 1275675985.12835754.1513095723265.JavaMail.zimbra@redhat.com Link: https://lkml.kernel.org/n/tip-j2wbz9av1rw3thr3t0g4dtuk@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf test shell: Fix check open filename arg using 'perf trace' on s390x

2017-11-16T17:50:00Z

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 the '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 s390x create a platform dependent command line to enable the 'perf probe' call to listen to the 'openat' system call and get the expected output. Signed-off-by: Thomas-Mich Richter Tested-by: Arnaldo Carvalho de Melo Cc: Hendrik Brueckner Cc: Thomas-Mich Richter LPU-Reference: 20171114071847.2381-1-tmricht@linux.vnet.ibm.com Link: http://lkml.kernel.org/n/tip-3qf38jk0prz54rhmhyu871my@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf test shell: Check if 'perf probe' is available, skip tests if not

2017-08-15T13:54:25Z

Add a library function that checks if 'perf probe' is built into the tool being tested, skipping tests that need it. Testing it on a system after removing the library needed to build 'probe' as a perf subcommand: # perf test ping vfs_getname 59: Use vfs_getname probe to get syscall args filenames : Skip 60: probe libc's inet_pton & backtrace it with ping : Skip 61: Check open filename arg using perf trace + vfs_getname: Skip 62: Add vfs_getname probe to get syscall args filenames : Skip # perf probe perf: 'probe' is not a perf-command. See 'perf --help'. # Now reinstalling elfutils-libelf-devel on this Fedora 26 system to rebuild perf and then retest this: # perf test ping vfs_getname 60: Use vfs_getname probe to get syscall args filenames : Ok 61: probe libc's inet_pton & backtrace it with ping : Ok 62: Check open filename arg using perf trace + vfs_getname: Ok 63: Add vfs_getname probe to get syscall args filenames : Ok # Reported-by: Kim Phillips Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Michael Petlan Cc: Namhyung Kim Cc: Thomas Richter Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-ctdck2gzsskqhjzu3ebb62zm@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf test shell: Add test using vfs_getname + 'perf trace'

2017-08-11T19:06:30Z

Uses the 'perf test shell' library to add probe:vfs_getname to the system then use it with 'perf trace' using 'touch' to write to a temp file, then checks that that was captured by the vfs_getname was used by 'perf trace', that already handles "probe:vfs_getname" if present, and used in the "open" syscall "filename" argument beautifier. Testing it: # perf test "trace + vfs_getname" 61: Check open filename arg using perf trace + vfs_getname: Ok # # perf test -v "trace + vfs_getname" 61: Check open filename arg using perf trace + vfs_getname: --- start --- test child forked, pid 30846 Added new event: probe:vfs_getname (on getname_flags:72 with pathname=result->name:string) You can now use it in all perf tools, such as: perf record -e probe:vfs_getname -aR sleep 1 2.237 ( 0.012 ms): touch/30855 open(filename: /tmp/temporary_file.kmoWQ, flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: IRUGO|IWUGO) = 3 test child finished with 0 ---- end ---- Check open filename arg using perf trace + vfs_getname: Ok # Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Michael Petlan Cc: Namhyung Kim Cc: Thomas Richter Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-j02nobfvvn9c7yrphdsnbqx0@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo