From 447ba88658faa8dbfd29d557daa38b7d88f460ec Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Thu, 25 May 2023 20:54:00 +0800 Subject: mm: compaction: add trace event for fast freepages isolation The fast_isolate_freepages() can also isolate freepages, but we can not know the fast isolation efficiency to understand the fast isolation pressure. So add a trace event to show some numbers to help to understand the efficiency for fast freepages isolation. Link: https://lkml.kernel.org/r/78d2932d0160d122c15372aceb3f2c45460a17fc.1685018752.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang Acked-by: Vlastimil Babka Cc: Mel Gorman Signed-off-by: Andrew Morton --- mm/compaction.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'mm/compaction.c') diff --git a/mm/compaction.c b/mm/compaction.c index 3b09d8d02581..ce6293bf9c4a 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1416,7 +1416,7 @@ static int next_search_order(struct compact_control *cc, int order) static void fast_isolate_freepages(struct compact_control *cc) { unsigned int limit = max(1U, freelist_scan_limit(cc) >> 1); - unsigned int nr_scanned = 0; + unsigned int nr_scanned = 0, total_isolated = 0; unsigned long low_pfn, min_pfn, highest = 0; unsigned long nr_isolated = 0; unsigned long distance; @@ -1515,6 +1515,7 @@ static void fast_isolate_freepages(struct compact_control *cc) set_page_private(page, order); nr_isolated = 1 << order; nr_scanned += nr_isolated - 1; + total_isolated += nr_isolated; cc->nr_freepages += nr_isolated; list_add_tail(&page->lru, &cc->freepages); count_compact_events(COMPACTISOLATED, nr_isolated); @@ -1535,6 +1536,9 @@ static void fast_isolate_freepages(struct compact_control *cc) limit = max(1U, limit >> 1); } + trace_mm_compaction_fast_isolate_freepages(min_pfn, cc->free_pfn, + nr_scanned, total_isolated); + if (!page) { cc->fast_search_fail++; if (scan_start) { -- cgit v1.2.3-58-ga151