On 5/11/22 05:33, Roman Gushchin wrote: > On Fri, May 06, 2022 at 10:29:25PM +0300, Vasily Averin wrote: >> TRACE_EVENT(percpu_alloc_percpu, >> >> - TP_PROTO(bool reserved, bool is_atomic, size_t size, >> - size_t align, void *base_addr, int off, void __percpu *ptr), >> + TP_PROTO(unsigned long call_site, >> + bool reserved, bool is_atomic, size_t size, >> + size_t align, void *base_addr, int off, >> + void __percpu *ptr, size_t bytes_alloc, gfp_t gfp_flags), > > Don't we want to preserve the order and add the call_site at the end? > Trace events are not ABI, but if we don't have a strong reason to break it, > I'd preserve the old order. I checked recent trace patches and found that order changes is acceptable. commit 8c39b8bc82aafcc8dd378bd79c76fac8e8a89c8d Author: David Howells <dhowells@xxxxxxxxxx> Date: Fri Jan 14 11:44:54 2022 +0000 cachefiles: Make some tracepoint adjustments - TP_printk("o=%08x i=%lx e=%d", - __entry->obj, __entry->ino, __entry->error) + TP_printk("o=%08x dB=%lx B=%lx e=%d", + __entry->obj, __entry->dino, __entry->ino, __entry->error) On the other hand I'm agree to keep old order by default. that's why I added bytes_alloc and gfp_flags to end of output. However I think call_site is an exception. In all cases found, call_site is output first. For me personally it simplified output parsing. So I would like to know Steven's position on this question. Thank you, Vasily Averin