perf trace: Add 'string' event alias to select syscalls with string args
Will be used in conjunction with the change to augmented_raw_syscalls.c
in the next cset that adds all syscalls with a first or second arg
string.
With just what we have in the syscall tracepoints we get:
# perf trace -e string ls > /dev/null
? ( ): ls/22382 ... [continued]: execve()) = 0
0.043 ( 0.004 ms): ls/22382 access(filename: 0x51ad420, mode: R) = -1 ENOENT (No such file or directory)
0.051 ( 0.004 ms): ls/22382 openat(dfd: CWD, filename: 0x51aa8b3, flags: RDONLY|CLOEXEC) = 3
0.071 ( 0.004 ms): ls/22382 openat(dfd: CWD, filename: 0x51b4d00, flags: RDONLY|CLOEXEC) = 3
0.138 ( 0.009 ms): ls/22382 openat(dfd: CWD, filename: 0x51684d0, flags: RDONLY|CLOEXEC) = 3
0.192 ( 0.004 ms): ls/22382 openat(dfd: CWD, filename: 0x51689c0, flags: RDONLY|CLOEXEC) = 3
0.255 ( 0.004 ms): ls/22382 openat(dfd: CWD, filename: 0x5168eb0, flags: RDONLY|CLOEXEC) = 3
0.342 ( 0.003 ms): ls/22382 openat(dfd: CWD, filename: 0x51693a0, flags: RDONLY|CLOEXEC) = 3
0.380 ( 0.003 ms): ls/22382 openat(dfd: CWD, filename: 0x5169950, flags: RDONLY|CLOEXEC) = 3
0.670 ( 0.011 ms): ls/22382 statfs(pathname: 0x515c783, buf: 0x7fff54d75b70) = 0
0.683 ( 0.005 ms): ls/22382 statfs(pathname: 0x515c783, buf: 0x7fff54d75a60) = 0
0.725 ( 0.004 ms): ls/22382 access(filename: 0x515c7ab) = 0
0.744 ( 0.005 ms): ls/22382 openat(dfd: CWD, filename: 0x50fba20, flags: RDONLY|CLOEXEC) = 3
0.793 ( 0.004 ms): ls/22382 openat(dfd: CWD, filename: 0x9e3e8390, flags: RDONLY|CLOEXEC|DIRECTORY|NONBLOCK) = 3
0.921 ( 0.006 ms): ls/22382 openat(dfd: CWD, filename: 0x50f7d90) = 3
#
If we put the vfs_getname probe point in place:
# perf probe 'vfs_getname=getname_flags:73 pathname=result->name:string'
Added new events:
probe:vfs_getname (on getname_flags:73 with pathname=result->name:string)
probe:vfs_getname_1 (on getname_flags:73 with pathname=result->name:string)
You can now use it in all perf tools, such as:
perf record -e probe:vfs_getname_1 -aR sleep 1
# perf trace -e string ls > /dev/null
? ( ): ls/22440 ... [continued]: execve()) = 0
0.048 ( 0.008 ms): ls/22440 access(filename: /etc/ld.so.preload, mode: R) = -1 ENOENT (No such file or directory)
0.061 ( 0.007 ms): ls/22440 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: RDONLY|CLOEXEC) = 3
0.092 ( 0.008 ms): ls/22440 openat(dfd: CWD, filename: /lib64/libselinux.so.1, flags: RDONLY|CLOEXEC) = 3
0.165 ( 0.007 ms): ls/22440 openat(dfd: CWD, filename: /lib64/libcap.so.2, flags: RDONLY|CLOEXEC) = 3
0.216 ( 0.007 ms): ls/22440 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: RDONLY|CLOEXEC) = 3
0.282 ( 0.007 ms): ls/22440 openat(dfd: CWD, filename: /lib64/libpcre2-8.so.0, flags: RDONLY|CLOEXEC) = 3
0.340 ( 0.007 ms): ls/22440 openat(dfd: CWD, filename: /lib64/libdl.so.2, flags: RDONLY|CLOEXEC) = 3
0.383 ( 0.007 ms): ls/22440 openat(dfd: CWD, filename: /lib64/libpthread.so.0, flags: RDONLY|CLOEXEC) = 3
0.697 ( 0.021 ms): ls/22440 statfs(pathname: /sys/fs/selinux, buf: 0x7ffee7dc9010) = 0
0.720 ( 0.007 ms): ls/22440 statfs(pathname: /sys/fs/selinux, buf: 0x7ffee7dc8f00) = 0
0.757 ( 0.007 ms): ls/22440 access(filename: /etc/selinux/config) = 0
0.779 ( 0.009 ms): ls/22440 openat(dfd: CWD, filename: /usr/lib/locale/locale-archive, flags: RDONLY|CLOEXEC) = 3
0.830 ( 0.006 ms): ls/22440 openat(dfd: CWD, filename: ., flags: RDONLY|CLOEXEC|DIRECTORY|NONBLOCK) = 3
0.958 ( 0.010 ms): ls/22440 openat(dfd: CWD, filename: /usr/lib64/gconv/gconv-modules.cache) = 3
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-6fh1myvn7ulf4xwq9iz3o776@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2b64b2ed27