[PATCH 16/41] perf trace: Beautify 'fsmount' arguments

Arnaldo Carvalho de Melo
2019-05-29T13:37:35Z

From: Arnaldo Carvalho de Melo <acme@redhat.com>

Use existing beautifiers for the first arg, fd, assigned using the
heuristic that looks for syscall arg names and associates SCA_FD with
'fd' named argumes, and wire up the recently introduced fsmount
attr_flags table generator.

Now it should be possible to just use:

perf trace -e fsmount

As root and see all fsmount syscalls with its args beautified.

# cat sys_fsmount.c
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <unistd.h>
#include <sys/syscall.h> /* For SYS_xxx definitions */

#define __NR_fsmount 432

#define MOUNT_ATTR_RDONLY 0x00000001 /* Mount read-only */
#define MOUNT_ATTR_NOSUID 0x00000002 /* Ignore suid and sgid bits */
#define MOUNT_ATTR_NODEV 0x00000004 /* Disallow access to device special files */
#define MOUNT_ATTR_NOEXEC 0x00000008 /* Disallow program execution */
#define MOUNT_ATTR__ATIME 0x00000070 /* Setting on how atime should be updated */
#define MOUNT_ATTR_RELATIME 0x00000000 /* - Update atime relative to mtime/ctime. */
#define MOUNT_ATTR_NOATIME 0x00000010 /* - Do not update access times. */
#define MOUNT_ATTR_STRICTATIME 0x00000020 /* - Always perform atime updates */
#define MOUNT_ATTR_NODIRATIME 0x00000080 /* Do not update directory access times */

static inline int sys_fsmount(int fs_fd, int flags, int attr_flags)
{
syscall(__NR_fsmount, fs_fd, flags, attr_flags);
}

int main(int argc, char *argv[])
{
int attr_flags = 0, fs_fd = 0;

sys_fsmount(fs_fd++, 0, attr_flags);
attr_flags |= MOUNT_ATTR_RDONLY;
sys_fsmount(fs_fd++, 1, attr_flags);
attr_flags |= MOUNT_ATTR_NOSUID;
sys_fsmount(fs_fd++, 0, attr_flags);
attr_flags |= MOUNT_ATTR_NODEV;
sys_fsmount(fs_fd++, 1, attr_flags);
attr_flags |= MOUNT_ATTR_NOEXEC;
sys_fsmount(fs_fd++, 0, attr_flags);
attr_flags |= MOUNT_ATTR_NOATIME;
sys_fsmount(fs_fd++, 1, attr_flags);
attr_flags |= MOUNT_ATTR_STRICTATIME;
sys_fsmount(fs_fd++, 0, attr_flags);
attr_flags |= MOUNT_ATTR_NODIRATIME;
sys_fsmount(fs_fd++, 0, attr_flags);
return 0;
}
#
# perf trace -e fsmount ./sys_fsmount
fsmount(0, 0, MOUNT_ATTR_RELATIME) = -1 EINVAL (Invalid argument)
fsmount(1, FSMOUNT_CLOEXEC, MOUNT_ATTR_RDONLY|MOUNT_ATTR_RELATIME) = -1 EINVAL (Invalid argument)
fsmount(2, 0, MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_RELATIME) = -1 EINVAL (Invalid argument)
fsmount(3, FSMOUNT_CLOEXEC, MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_RELATIME) = -1 EBADF (Bad file descriptor)
fsmount(4, 0, MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_RELATIME) = -1 EBADF (Bad file descriptor)
fsmount(5, FSMOUNT_CLOEXEC, MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_NOATIME) = -1 EBADF (Bad file descriptor)
fsmount(6, 0, MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_NOATIME|MOUNT_ATTR_STRICTATIME) = -1 EINVAL (Invalid argument)
fsmount(7, 0, MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_NOATIME|MOUNT_ATTR_STRICTATIME|MOUNT_ATTR_NODIRATIME) = -1 EINVAL (Invalid argument)
#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-w71uge0sfo6ns9uclhwtthca@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/Makefile.perf | 8 ++++++++
tools/perf/builtin-trace.c | 12 +++++++++++
tools/perf/trace/beauty/Build | 1 +
tools/perf/trace/beauty/beauty.h | 3 +++
tools/perf/trace/beauty/fsmount.c | 34 +++++++++++++++++++++++++++++++
5 files changed, 58 insertions(+)
create mode 100644 tools/perf/trace/beauty/fsmount.c

diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 22e92a9ee871..326ca5d6a7ef 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -419,6 +419,12 @@ fadvise_advice_tbl := $(srctree)/tools/perf/trace/beauty/fadvise.sh
$(fadvise_advice_array): $(linux_uapi_dir)/in.h $(fadvise_advice_tbl)
$(Q)$(SHELL) '$(fadvise_advice_tbl)' $(linux_uapi_dir) > $@

+fsmount_arrays := $(beauty_outdir)/fsmount_arrays.c
+fsmount_tbls := $(srctree)/tools/perf/trace/beauty/fsmount.sh
+
+$(fsmount_arrays): $(linux_uapi_dir)/fs.h $(fsmount_tbls)
+ $(Q)$(SHELL) '$(fsmount_tbls)' $(linux_uapi_dir) > $@
+
fspick_arrays := $(beauty_outdir)/fspick_arrays.c
fspick_tbls := $(srctree)/tools/perf/trace/beauty/fspick.sh

@@ -647,6 +653,7 @@ build-dir = $(if $(__build-dir),$(__build-dir),.)
prepare: $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h archheaders $(drm_ioctl_array) \
$(fadvise_advice_array) \
$(fsconfig_arrays) \
+ $(fsmount_arrays) \
$(fspick_arrays) \
$(pkey_alloc_access_rights_array) \
$(sndrv_pcm_ioctl_array) \
@@ -944,6 +951,7 @@ clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clea
$(OUTPUT)pmu-events/pmu-events.c \
$(OUTPUT)$(fadvise_advice_array) \
$(OUTPUT)$(fsconfig_arrays) \
+ $(OUTPUT)$(fsmount_arrays) \
$(OUTPUT)$(fspick_arrays) \
$(OUTPUT)$(madvise_behavior_array) \
$(OUTPUT)$(mmap_flags_array) \
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 16bb8c04c689..3a2ab68a8b85 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -487,6 +487,11 @@ static const char *bpf_cmd[] = {
};
static DEFINE_STRARRAY(bpf_cmd, "BPF_");

+static const char *fsmount_flags[] = {
+ [1] = "CLOEXEC",
+};
+static DEFINE_STRARRAY(fsmount_flags, "FSMOUNT_");
+
#include "trace/beauty/generated/fsconfig_arrays.c"

static DEFINE_STRARRAY(fsconfig_cmds, "FSCONFIG_");
@@ -651,6 +656,10 @@ static size_t syscall_arg__scnprintf_getrandom_flags(char *bf, size_t size,
{ .scnprintf = SCA_STRARRAY, \
.parm = &strarray__##array, }

+#define STRARRAY_FLAGS(name, array) \
+ { .scnprintf = SCA_STRARRAY_FLAGS, \
+ .parm = &strarray__##array, }
+
#include "trace/beauty/arch_errno_names.c"
#include "trace/beauty/eventfd.c"
#include "trace/beauty/futex_op.c"
@@ -724,6 +733,9 @@ static struct syscall_fmt {
.arg = { [1] = { .scnprintf = SCA_FLOCK, /* cmd */ }, }, },
{ .name = "fsconfig",
.arg = { [1] = STRARRAY(cmd, fsconfig_cmds), }, },
+ { .name = "fsmount",
+ .arg = { [1] = STRARRAY_FLAGS(flags, fsmount_flags),
+ [2] = { .scnprintf = SCA_FSMOUNT_ATTR_FLAGS, /* attr_flags */ }, }, },
{ .name = "fspick",
.arg = { [0] = { .scnprintf = SCA_FDAT, /* dfd */ },
[1] = { .scnprintf = SCA_FILENAME, /* path */ },
diff --git a/tools/perf/trace/beauty/Build b/tools/perf/trace/beauty/Build
index c2d38b2b606b..338c61b8ed22 100644
--- a/tools/perf/trace/beauty/Build
+++ b/tools/perf/trace/beauty/Build
@@ -1,6 +1,7 @@
perf-y += clone.o
perf-y += fcntl.o
perf-y += flock.o
+perf-y += fsmount.o
perf-y += fspick.o
ifeq ($(SRCARCH),$(filter $(SRCARCH),x86))
perf-y += ioctl.o
diff --git a/tools/perf/trace/beauty/beauty.h b/tools/perf/trace/beauty/beauty.h
index ad874e0beba5..9385d1cb121a 100644
--- a/tools/perf/trace/beauty/beauty.h
+++ b/tools/perf/trace/beauty/beauty.h
@@ -144,6 +144,9 @@ size_t syscall_arg__scnprintf_fcntl_arg(char *bf, size_t size, struct syscall_ar
size_t syscall_arg__scnprintf_flock(char *bf, size_t size, struct syscall_arg *arg);
#define SCA_FLOCK syscall_arg__scnprintf_flock

+size_t syscall_arg__scnprintf_fsmount_attr_flags(char *bf, size_t size, struct syscall_arg *arg);
+#define SCA_FSMOUNT_ATTR_FLAGS syscall_arg__scnprintf_fsmount_attr_flags
+
size_t syscall_arg__scnprintf_fspick_flags(char *bf, size_t size, struct syscall_arg *arg);
#define SCA_FSPICK_FLAGS syscall_arg__scnprintf_fspick_flags

diff --git a/tools/perf/trace/beauty/fsmount.c b/tools/perf/trace/beauty/fsmount.c
new file mode 100644
index 000000000000..30c8c082a3c3
--- /dev/null
+++ b/tools/perf/trace/beauty/fsmount.c
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * trace/beauty/fsmount.c
+ *
+ * Copyright (C) 2019, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
+ */
+
+#include "trace/beauty/beauty.h"
+#include <linux/log2.h>
+#include <uapi/linux/mount.h>
+
+static size_t fsmount__scnprintf_attr_flags(unsigned long flags, char *bf, size_t size, bool show_prefix)
+{
+#include "trace/beauty/generated/fsmount_arrays.c"
+ static DEFINE_STRARRAY(fsmount_attr_flags, "MOUNT_ATTR_");
+ size_t printed = 0;
+
+ if ((flags & ~MOUNT_ATTR__ATIME) != 0)
+ printed += strarray__scnprintf_flags(&strarray__fsmount_attr_flags, bf, size, show_prefix, flags);
+
+ if ((flags & MOUNT_ATTR__ATIME) == MOUNT_ATTR_RELATIME) {
+ printed += scnprintf(bf + printed, size - printed, "%s%s%s",
+ printed ? "|" : "", show_prefix ? "MOUNT_ATTR_" : "", "RELATIME");
+ }
+
+ return printed;
+}
+
+size_t syscall_arg__scnprintf_fsmount_attr_flags(char *bf, size_t size, struct syscall_arg *arg)
+{
+ unsigned long flags = arg->val;
+
+ return fsmount__scnprintf_attr_flags(flags, bf, size, arg->show_string_prefix);
+}
--
2.20.1