ANDROID: mm: create vendor hooks for page alloc

Add vendor hook inside of get_page_from_freelist() to check
and modify the watermark in some special situations.
Additional page flag bit will be set for future identification.

Separately, a vendor hook inside of page_add_new_anon_rmap()
is added to set the referenced bit in some situations, e.g.
if the special bit in the page flag mentioned before is set,
we will give this page one more chance before it gets reclaimed.

Bug: 279793368
Bug: 336900791

Change-Id: I363853a050a87201f6f368ccc580485dddd6c6b6
Signed-off-by: Dezhi Huang <huangdezhi@hihonor.com>
Signed-off-by: huzhanyuan <huzhanyuan@oppo.com>
(cherry picked from commit 49fa9c5a7e11922caa132a0d014b46b7a72f10d3)

drivers/android/vendor_hooks.c

@@ -224,6 +224,8 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_binder_special_task);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_binder_buffer_release);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mglru_should_abort_scan);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_do_shrink_slab);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_get_page_wmark);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_page_add_new_anon_rmap);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_check_folio_look_around_ref);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_look_around);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_look_around_migrate_folio);

include/trace/hooks/mm.h

@@ -199,6 +199,13 @@ DECLARE_HOOK(android_vh_show_smap,
 		unsigned long swap_shared, unsigned long writeback,
 		unsigned long same, unsigned long huge),
 	TP_ARGS(m, swap_shared, writeback, same, huge));
+DECLARE_HOOK(android_vh_get_page_wmark,
+	TP_PROTO(unsigned int alloc_flags, unsigned long *page_wmark),
+	TP_ARGS(alloc_flags, page_wmark));
+DECLARE_HOOK(android_vh_page_add_new_anon_rmap,
+	TP_PROTO(struct page *page, struct vm_area_struct *vma,
+		unsigned long address),
+	TP_ARGS(page, vma, address));
 DECLARE_HOOK(android_vh_alloc_pages_slowpath_start,
 	TP_PROTO(u64 *stime),
 	TP_ARGS(stime));

mm/page_alloc.c

@@ -66,6 +66,9 @@
 EXPORT_TRACEPOINT_SYMBOL_GPL(mm_page_alloc);
 EXPORT_TRACEPOINT_SYMBOL_GPL(mm_page_free);
 
+#undef CREATE_TRACE_POINTS
+#include <trace/hooks/mm.h>
+
 /* Free Page Internal flags: for internal, non-pcp variants of free_pages(). */
 typedef int __bitwise fpi_t;
 
@@ -3682,6 +3685,7 @@ retry:
 
 check_alloc_wmark:
 		mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK);
+		trace_android_vh_get_page_wmark(alloc_flags, &mark);
 		if (!zone_watermark_fast(zone, order, mark,
 				       ac->highest_zoneidx, alloc_flags,
 				       gfp_mask)) {

mm/rmap.c

@@ -1470,6 +1470,7 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma,
 
 	__folio_mod_stat(folio, nr, nr_pmdmapped);
 	mod_mthp_stat(folio_order(folio), MTHP_STAT_NR_ANON, 1);
+	trace_android_vh_page_add_new_anon_rmap(&folio->page, vma, address);
 }
 
 static __always_inline void __folio_add_file_rmap(struct folio *folio,