On 10/31/26 at 05:00pm, Ridong Chen wrote: > From: Ridong Chen <[email protected]> > > MGLRU's scan_folios() emits the classic-LRU tracepoint > trace_mm_vmscan_lru_isolate(), which predates MGLRU. It reports the > scan/isolate counts and the LRU type, but carries no generation or > memcg context, so a trace of an MGLRU run cannot tell which memcg a > given scan belongs to, nor how far reclaim has progressed through the > generations. > > Add mm_mglru_scan_folios next to it, reporting the same counters plus > nr_sorted (folios moved to a younger generation by sort_folio()) and > the context the classic tracepoint lacks: the node id and memcg id of > the lruvec, and the max_seq, tier and min_seq of the type being > scanned. > > Now that struct scan_control is visible to the trace header, pass sc, > lruvec, type and tier straight in and derive everything else in > TP_fast_assign(), so nothing is computed at the call site when the > event is disabled. The int fields are grouped at the end of the entry > to avoid padding on 64-bit. > > scan_folios() is the MGLRU-specific layer where folios are actually > scanned, so it has no classic-LRU counterpart. The existing tracepoint > is left unchanged. > > Signed-off-by: Ridong Chen <[email protected]> > --- > mm/trace_vmscan.h | 66 +++++++++++++++++++++++++++++++++++++++++++++++ > mm/vmscan.c | 2 ++ > 2 files changed, 68 insertions(+) > > diff --git a/mm/trace_vmscan.h b/mm/trace_vmscan.h > index b2ad83e5f25e..8148b8224422 100644 > --- a/mm/trace_vmscan.h > +++ b/mm/trace_vmscan.h > @@ -392,6 +392,72 @@ TRACE_EVENT(mm_vmscan_lru_isolate, > __print_symbolic(__entry->lru, LRU_NAMES)) > ); > > +#ifdef CONFIG_LRU_GEN > +TRACE_EVENT(mm_mglru_scan_folios, > + > + TP_PROTO(struct lruvec *lruvec, > + struct scan_control *sc, > + unsigned long nr_requested, > + unsigned long nr_scanned, > + unsigned long nr_sorted, > + unsigned long nr_skipped, > + unsigned long nr_taken, > + int type, > + int tier), > + > + TP_ARGS(lruvec, sc, nr_requested, nr_scanned, nr_sorted, nr_skipped, > + nr_taken, type, tier), > + > + TP_STRUCT__entry( > + __field(u64, memcg_id) > + __field(unsigned long, nr_requested) > + __field(unsigned long, nr_scanned) > + __field(unsigned long, nr_sorted) > + __field(unsigned long, nr_skipped) > + __field(unsigned long, nr_taken) > + __field(unsigned long, max_seq) > + __field(unsigned long, min_seq) > + __field(int, nid)
Now it has nid printed out, it's cool. This patch looks good to me, thanks. Reviewed-by: Baoquan He <[email protected]> > + __field(int, highest_zoneidx) > + __field(int, order) > + __field(int, lru) > + __field(int, tier) > + ), > + > + TP_fast_assign( > + __entry->memcg_id = mem_cgroup_id(lruvec_memcg(lruvec)); > + __entry->nr_requested = nr_requested; > + __entry->nr_scanned = nr_scanned; > + __entry->nr_sorted = nr_sorted; > + __entry->nr_skipped = nr_skipped; > + __entry->nr_taken = nr_taken; > + __entry->max_seq = lruvec->lrugen.max_seq; > + __entry->min_seq = lruvec->lrugen.min_seq[type]; > + __entry->nid = lruvec_pgdat(lruvec)->node_id; > + __entry->highest_zoneidx = sc->reclaim_idx; > + __entry->order = sc->order; > + __entry->lru = type ? LRU_INACTIVE_FILE : LRU_INACTIVE_ANON; > + __entry->tier = tier; > + ), > + > + TP_printk("nid=%d memcg_id=%llu classzone=%d order=%d nr_requested=%lu > nr_scanned=%lu nr_sorted=%lu nr_skipped=%lu nr_taken=%lu lru=%s max_seq=%lu > tier=%d min_seq=%lu", > + __entry->nid, > + __entry->memcg_id, > + __entry->highest_zoneidx, > + __entry->order, > + __entry->nr_requested, > + __entry->nr_scanned, > + __entry->nr_sorted, > + __entry->nr_skipped, > + __entry->nr_taken, > + __print_symbolic(__entry->lru, LRU_NAMES), > + __entry->max_seq, > + __entry->tier, > + __entry->min_seq) > +); > + > +#endif /* CONFIG_LRU_GEN */ > + > TRACE_EVENT(mm_vmscan_write_folio, > > TP_PROTO(struct folio *folio), > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 15e9184a580a..ff51fee872f8 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -4852,6 +4852,8 @@ static int scan_folios(unsigned long nr_to_scan, struct > lruvec *lruvec, > trace_mm_vmscan_lru_isolate(sc, nr_to_scan, > scanned, skipped, isolated, > type ? LRU_INACTIVE_FILE : > LRU_INACTIVE_ANON); > + trace_mm_mglru_scan_folios(lruvec, sc, nr_to_scan, scanned, sorted, > + skipped, isolated, type, tier); > > *isolatedp = isolated; > return scanned; > -- > 2.43.0 >
