tracing: Remove __assign_str_len()

Now that __assign_str() gets the length from the __string() (and
__string_len()) macros, there's no reason to have a separate
__assign_str_len() macro as __assign_str() can get the length of the
string needed.

Also remove __assign_rel_str() although it had no users anyway.

Link: https://lore.kernel.org/linux-trace-kernel/20240223152206.0b650659@gandalf.local.home
Cc: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 288a796..1cd2076 100644 (file)
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -104,7 +104,7 @@ TRACE_EVENT(nfsd_compound,
        TP_fast_assign(
                __entry->xid = be32_to_cpu(rqst->rq_xid);
                __entry->opcnt = opcnt;
-               __assign_str_len(tag, tag, taglen);
+               __assign_str(tag, tag);
        ),
        TP_printk("xid=0x%08x opcnt=%u tag=%s",
                __entry->xid, __entry->opcnt, __get_str(tag)
@@ -485,7 +485,7 @@ TRACE_EVENT(nfsd_dirent,
        TP_fast_assign(
                __entry->fh_hash = fhp ? knfsd_fh_hash(&fhp->fh_handle) : 0;
                __entry->ino = ino;
-               __assign_str_len(name, name, namlen)
+               __assign_str(name, name);
        ),
        TP_printk("fh_hash=0x%08x ino=%llu name=%s",
                __entry->fh_hash, __entry->ino, __get_str(name)
@@ -906,7 +906,7 @@ DECLARE_EVENT_CLASS(nfsd_clid_class,
                __entry->flavor = clp->cl_cred.cr_flavor;
                memcpy(__entry->verifier, (void *)&clp->cl_verifier,
                       NFS4_VERIFIER_SIZE);
-               __assign_str_len(name, clp->cl_name.data, clp->cl_name.len);
+               __assign_str(name, clp->cl_name.data);
        ),
        TP_printk("addr=%pISpc name='%s' verifier=0x%s flavor=%s client=%08x:%08x",
                __entry->addr, __get_str(name),
@@ -1976,7 +1976,7 @@ TRACE_EVENT(nfsd_ctl_time,
        TP_fast_assign(
                __entry->netns_ino = net->ns.inum;
                __entry->time = time;
-               __assign_str_len(name, name, namelen);
+               __assign_str(name, name);
        ),
        TP_printk("file=%s time=%d\n",
                __get_str(name), __entry->time

diff --git a/include/trace/stages/stage6_event_callback.h b/include/trace/stages/stage6_event_callback.h
index 2bfd497..0c0f50b 100644 (file)
--- a/include/trace/stages/stage6_event_callback.h
+++ b/include/trace/stages/stage6_event_callback.h
@@ -32,16 +32,13 @@
 
 #undef __assign_str
 #define __assign_str(dst, src)                                         \
-       memcpy(__get_str(dst), __data_offsets.dst##_ptr_ ? : EVENT_NULL_STR, \
-              __get_dynamic_array_len(dst))
-
-#undef __assign_str_len
-#define __assign_str_len(dst, src, len)                                        \
        do {                                                            \
-               memcpy(__get_str(dst),                                  \
-                      __data_offsets.dst##_ptr_ ? : EVENT_NULL_STR, len); \
-               __get_str(dst)[len] = '\0';                             \
-       } while(0)
+               char *__str__ = __get_str(dst);                         \
+               int __len__ = __get_dynamic_array_len(dst) - 1;         \
+               memcpy(__str__, __data_offsets.dst##_ptr_ ? :           \
+                      EVENT_NULL_STR, __len__);                        \
+               __str__[__len__] = '\0';                                \
+       } while (0)
 
 #undef __assign_vstr
 #define __assign_vstr(dst, fmt, va)                                    \
@@ -94,15 +91,12 @@
 
 #undef __assign_rel_str
 #define __assign_rel_str(dst, src)                                     \
-       memcpy(__get_rel_str(dst), __data_offsets.dst##_ptr_ ? : EVENT_NULL_STR, \
-              __get_rel_dynamic_array_len(dst))
-
-#undef __assign_rel_str_len
-#define __assign_rel_str_len(dst, src, len)                            \
        do {                                                            \
-               memcpy(__get_rel_str(dst),                              \
-                      __data_offsets.dst##_ptr_ ? : EVENT_NULL_STR, len); \
-               __get_rel_str(dst)[len] = '\0';                         \
+               char *__str__ = __get_rel_str(dst);                     \
+               int __len__ = __get_rel_dynamic_array_len(dst) - 1;     \
+               memcpy(__str__, __data_offsets.dst##_ptr_ ? :           \
+                      EVENT_NULL_STR, __len__);                        \
+               __str__[__len__] = '\0';                                \
        } while (0)
 
 #undef __rel_bitmask

diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
index 23f923c..f2d2d56 100644 (file)
--- a/samples/trace_events/trace-events-sample.h
+++ b/samples/trace_events/trace-events-sample.h
@@ -163,8 +163,7 @@
  *         __string().
  *
  *   __string_len: This is a helper to a __dynamic_array, but it understands
- *        that the array has characters in it, and with the combined
- *         use of __assign_str_len(), it will allocate 'len' + 1 bytes
+ *        that the array has characters in it, it will allocate 'len' + 1 bytes
  *         in the ring buffer and add a '\0' to the string. This is
  *         useful if the string being saved has no terminating '\0' byte.
  *         It requires that the length of the string is known as it acts
@@ -174,9 +173,11 @@
  *
  *         __string_len(foo, bar, len)
  *
- *         To assign this string, use the helper macro __assign_str_len().
+ *         To assign this string, use the helper macro __assign_str().
+ *         The length is saved via the __string_len() and is retrieved in
+ *         __assign_str().
  *
- *         __assign_str_len(foo, bar, len);
+ *         __assign_str(foo, bar);
  *
  *         Then len + 1 is allocated to the ring buffer, and a nul terminating
  *         byte is added. This is similar to: