From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx> 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. Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> --- Changes since v2: https://lore.kernel.org/linux-trace-kernel/20240223144840.563660e1@xxxxxxxxxxxxxxxxxx/ - I just realized that __assign_str_len() makes sure that the string ends with a '\0'. To use __assign_str(), it too must write a '\0' at the end of the string. fs/nfsd/trace.h | 8 +++--- include/trace/stages/stage6_event_callback.h | 28 ++++++++------------ samples/trace_events/trace-events-sample.h | 9 ++++--- 3 files changed, 20 insertions(+), 25 deletions(-) diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h index 2cd57033791f..98b14f30d772 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -102,7 +102,7 @@ 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) @@ -483,7 +483,7 @@ 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) @@ -853,7 +853,7 @@ 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), @@ -1800,7 +1800,7 @@ 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 2bfd49713b42..0c0f50bcdc56 100644 --- 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 23f923ccd529..f2d2d56ce8e2 100644 --- 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: -- 2.43.0
