ANDROID: vendor_hooks:vendor hook for madvise_cold_or_pageout_pte_range.

add vendor hook in madvise_cold_or_pageout_pte_range to control the
pages to be reclaimed more fine-grained.

Bug: 284808098
Signed-off-by: zhouwenhao <zhouwenhao@xiaomi.com>
Change-Id: I298fde436df192cea9b1541d857f3a46808e06f2
Signed-off-by: xiaofeng <xiaofeng5@xiaomi.com>

drivers/android/vendor_hooks.c

@@ -521,3 +521,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mm_direct_reclaim_enter);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mm_direct_reclaim_exit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mm_may_oom_exit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_calculate_totalreserve_pages);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_madvise_cold_pageout_skip);

include/trace/hooks/mm.h

@@ -49,6 +49,9 @@ DECLARE_RESTRICTED_HOOK(android_rvh_bitmap_find_best_next_area,
 				bool status),
 			TP_ARGS(bitmap, bitmap_maxno, start, bitmap_count, mask,
 				offset, bitmap_no, status), 1);
+DECLARE_HOOK(android_vh_madvise_cold_pageout_skip,
+	     TP_PROTO(struct vm_area_struct *vma, struct folio *folio, bool pageout, bool *need_skip),
+	     TP_ARGS(vma, folio, pageout, need_skip));
 /*
 
 DECLARE_RESTRICTED_HOOK(android_rvh_set_skip_swapcache_flags,

mm/madvise.c

@@ -447,6 +447,7 @@ restart:
 	flush_tlb_batched_pending(mm);
 	arch_enter_lazy_mmu_mode();
 	for (; addr < end; pte += nr, addr += nr * PAGE_SIZE) {
+		bool need_skip = false;
 		nr = 1;
 		ptent = ptep_get(pte);
 
@@ -470,6 +471,12 @@ restart:
 		if (!folio || folio_is_zone_device(folio))
 			continue;
 
+		trace_android_vh_madvise_cold_pageout_skip(vma, folio, pageout,
+			&need_skip);
+
+		if (need_skip)
+			continue;
+
 		/*
 		 * If we encounter a large folio, only split it if it is not
 		 * fully mapped within the range we are operating on. Otherwise