return err;
 }
 
-static int process_tracing_data(struct perf_file_section *section
-                               __maybe_unused,
-                             struct perf_header *ph __maybe_unused,
-                             int feat __maybe_unused, int fd, void *data)
+static int process_tracing_data(struct perf_file_section *section __maybe_unused,
+                               struct perf_header *ph __maybe_unused,
+                               int fd, void *data)
 {
        trace_report(fd, data, false);
        return 0;
 }
 
 static int process_build_id(struct perf_file_section *section,
-                           struct perf_header *ph,
-                           int feat __maybe_unused, int fd,
+                           struct perf_header *ph, int fd,
                            void *data __maybe_unused)
 {
        if (perf_header__read_build_ids(ph, fd, section->offset, section->size))
 }
 
 static int process_hostname(struct perf_file_section *section __maybe_unused,
-                           struct perf_header *ph, int feat __maybe_unused,
-                           int fd, void *data __maybe_unused)
+                           struct perf_header *ph, int fd,
+                           void *data __maybe_unused)
 {
        ph->env.hostname = do_read_string(fd, ph);
        return ph->env.hostname ? 0 : -ENOMEM;
 }
 
 static int process_osrelease(struct perf_file_section *section __maybe_unused,
-                            struct perf_header *ph, int feat __maybe_unused,
-                            int fd, void *data __maybe_unused)
+                            struct perf_header *ph, int fd,
+                            void *data __maybe_unused)
 {
        ph->env.os_release = do_read_string(fd, ph);
        return ph->env.os_release ? 0 : -ENOMEM;
 }
 
 static int process_version(struct perf_file_section *section __maybe_unused,
-                          struct perf_header *ph, int feat __maybe_unused,
-                          int fd, void *data __maybe_unused)
+                          struct perf_header *ph, int fd,
+                          void *data __maybe_unused)
 {
        ph->env.version = do_read_string(fd, ph);
        return ph->env.version ? 0 : -ENOMEM;
 }
 
 static int process_arch(struct perf_file_section *section __maybe_unused,
-                       struct perf_header *ph, int feat __maybe_unused,
-                       int fd, void *data __maybe_unused)
+                       struct perf_header *ph, int fd,
+                       void *data __maybe_unused)
 {
        ph->env.arch = do_read_string(fd, ph);
        return ph->env.arch ? 0 : -ENOMEM;
 }
 
 static int process_nrcpus(struct perf_file_section *section __maybe_unused,
-                         struct perf_header *ph, int feat __maybe_unused,
-                         int fd, void *data __maybe_unused)
+                         struct perf_header *ph, int fd,
+                         void *data __maybe_unused)
 {
        size_t ret;
        u32 nr;
 }
 
 static int process_cpudesc(struct perf_file_section *section __maybe_unused,
-                          struct perf_header *ph, int feat __maybe_unused,
-                          int fd, void *data __maybe_unused)
+                          struct perf_header *ph, int fd,
+                          void *data __maybe_unused)
 {
        ph->env.cpu_desc = do_read_string(fd, ph);
        return ph->env.cpu_desc ? 0 : -ENOMEM;
 }
 
 static int process_cpuid(struct perf_file_section *section __maybe_unused,
-                        struct perf_header *ph, int feat __maybe_unused,
-                        int fd, void *data __maybe_unused)
+                        struct perf_header *ph,  int fd,
+                        void *data __maybe_unused)
 {
        ph->env.cpuid = do_read_string(fd, ph);
        return ph->env.cpuid ? 0 : -ENOMEM;
 }
 
 static int process_total_mem(struct perf_file_section *section __maybe_unused,
-                            struct perf_header *ph, int feat __maybe_unused,
-                            int fd, void *data __maybe_unused)
+                            struct perf_header *ph, int fd,
+                            void *data __maybe_unused)
 {
        uint64_t mem;
        size_t ret;
 }
 
 static void
-perf_evlist__set_event_name(struct perf_evlist *evlist, struct perf_evsel *event)
+perf_evlist__set_event_name(struct perf_evlist *evlist,
+                           struct perf_evsel *event)
 {
        struct perf_evsel *evsel;
 
 
 static int
 process_event_desc(struct perf_file_section *section __maybe_unused,
-                  struct perf_header *header, int feat __maybe_unused, int fd,
+                  struct perf_header *header, int fd,
                   void *data __maybe_unused)
 {
-       struct perf_session *session = container_of(header, struct perf_session, header);
+       struct perf_session *session;
        struct perf_evsel *evsel, *events = read_event_desc(header, fd);
 
        if (!events)
                return 0;
 
+       session = container_of(header, struct perf_session, header);
        for (evsel = events; evsel->attr.size; evsel++)
                perf_evlist__set_event_name(session->evlist, evsel);
 
 }
 
 static int process_cmdline(struct perf_file_section *section __maybe_unused,
-                          struct perf_header *ph, int feat __maybe_unused,
-                          int fd, void *data __maybe_unused)
+                          struct perf_header *ph, int fd,
+                          void *data __maybe_unused)
 {
        size_t ret;
        char *str;
 }
 
 static int process_cpu_topology(struct perf_file_section *section __maybe_unused,
-                               struct perf_header *ph, int feat __maybe_unused,
-                               int fd, void *data __maybe_unused)
+                               struct perf_header *ph, int fd,
+                               void *data __maybe_unused)
 {
        size_t ret;
        u32 nr, i;
 }
 
 static int process_numa_topology(struct perf_file_section *section __maybe_unused,
-                                struct perf_header *ph, int feat __maybe_unused,
-                                int fd, void *data __maybe_unused)
+                                struct perf_header *ph, int fd,
+                                void *data __maybe_unused)
 {
        size_t ret;
        u32 nr, node, i;
 }
 
 static int process_pmu_mappings(struct perf_file_section *section __maybe_unused,
-                               struct perf_header *ph, int feat __maybe_unused,
-                               int fd, void *data __maybe_unused)
+                               struct perf_header *ph, int fd,
+                               void *data __maybe_unused)
 {
        size_t ret;
        char *name;
        void (*print)(struct perf_header *h, int fd, FILE *fp);
        char *(*read)(struct perf_header *h, int fd);
        int (*process)(struct perf_file_section *section,
-                      struct perf_header *h, int feat, int fd, void *data);
+                      struct perf_header *h, int fd, void *data);
        const char *name;
        bool full_only;
 };
        if (!feat_ops[feat].process)
                return 0;
 
-       return feat_ops[feat].process(section, ph, feat, fd, data);
+       return feat_ops[feat].process(section, ph, fd, data);
 }
 
 static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,