[PATCH v5 16/32] cachefiles: Add auxiliary data trace

David Howells
2024-12-16T20:43:46Z

Add a display of the first 8 bytes of the downloaded auxiliary data and of
the on-disk stored auxiliary data as these are used in coherency
management. In the case of afs, this holds the data version number.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
---
fs/cachefiles/xattr.c | 9 ++++++++-
include/trace/events/cachefiles.h | 13 ++++++++++---
2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c
index 7c6f260a3be5..52383b1d0ba6 100644
--- a/fs/cachefiles/xattr.c
+++ b/fs/cachefiles/xattr.c
@@ -77,6 +77,7 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object)
trace_cachefiles_vfs_error(object, file_inode(file), ret,
cachefiles_trace_setxattr_error);
trace_cachefiles_coherency(object, file_inode(file)->i_ino,
+ be64_to_cpup((__be64 *)buf->data),
buf->content,
cachefiles_coherency_set_fail);
if (ret != -ENOMEM)
@@ -85,6 +86,7 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object)
"Failed to set xattr with error %d", ret);
} else {
trace_cachefiles_coherency(object, file_inode(file)->i_ino,
+ be64_to_cpup((__be64 *)buf->data),
buf->content,
cachefiles_coherency_set_ok);
}
@@ -126,7 +128,10 @@ int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file
object,
"Failed to read aux with error %zd", xlen);
why = cachefiles_coherency_check_xattr;
- } else if (buf->type != CACHEFILES_COOKIE_TYPE_DATA) {
+ goto out;
+ }
+
+ if (buf->type != CACHEFILES_COOKIE_TYPE_DATA) {
why = cachefiles_coherency_check_type;
} else if (memcmp(buf->data, p, len) != 0) {
why = cachefiles_coherency_check_aux;
@@ -141,7 +146,9 @@ int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file
ret = 0;
}

+out:
trace_cachefiles_coherency(object, file_inode(file)->i_ino,
+ be64_to_cpup((__be64 *)buf->data),
buf->content, why);
kfree(buf);
return ret;
diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h
index 74114c261bcd..a743b2a35ea7 100644
--- a/include/trace/events/cachefiles.h
+++ b/include/trace/events/cachefiles.h
@@ -380,10 +380,11 @@ TRACE_EVENT(cachefiles_rename,
TRACE_EVENT(cachefiles_coherency,
TP_PROTO(struct cachefiles_object *obj,
ino_t ino,
+ u64 disk_aux,
enum cachefiles_content content,
enum cachefiles_coherency_trace why),

- TP_ARGS(obj, ino, content, why),
+ TP_ARGS(obj, ino, disk_aux, content, why),

/* Note that obj may be NULL */
TP_STRUCT__entry(
@@ -391,6 +392,8 @@ TRACE_EVENT(cachefiles_coherency,
__field(enum cachefiles_coherency_trace, why)
__field(enum cachefiles_content, content)
__field(u64, ino)
+ __field(u64, aux)
+ __field(u64, disk_aux)
),

TP_fast_assign(
@@ -398,13 +401,17 @@ TRACE_EVENT(cachefiles_coherency,
__entry->why = why;
__entry->content = content;
__entry->ino = ino;
+ __entry->aux = be64_to_cpup((__be64 *)obj->cookie->inline_aux);
+ __entry->disk_aux = disk_aux;
),

- TP_printk("o=%08x %s B=%llx c=%u",
+ TP_printk("o=%08x %s B=%llx c=%u aux=%llx dsk=%llx",
__entry->obj,
__print_symbolic(__entry->why, cachefiles_coherency_traces),
__entry->ino,
- __entry->content)
+ __entry->content,
+ __entry->aux,
+ __entry->disk_aux)
);

TRACE_EVENT(cachefiles_vol_coherency,