ngx_log_set_levels  453 core/ngx_log.c     return ngx_log_set_levels(cf, &cf->cycle->new_log);
ngx_log_set_levels  200 core/ngx_log.h char *ngx_log_set_levels(ngx_conf_t *cf, ngx_log_t *log);
ngx_log_set_levels 4299 http/ngx_http_core_module.c     return ngx_log_set_levels(cf, clcf->error_log);