ANDROID: vendor hook to control bh_lru and lru_cache_disable

Add vendor hook for bh_lru and lru_cache_disable

Bug: 238728493
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I81bfad317cf6e8633186ebb3238644306d7a102d
Signed-off-by: Richard Chang <richardycc@google.com>
(cherry picked from commit 74e2ea264cd1895c493b9008b62bfea98dacf3f6)

drivers/android/vendor_hooks.c

@@ -30,6 +30,7 @@
 #include <trace/hooks/ftrace_dump.h>
 #include <trace/hooks/ufshcd.h>
 #include <trace/hooks/block.h>
+#include <trace/hooks/buffer.h>
 #include <trace/hooks/cgroup.h>
 #include <trace/hooks/sys.h>
 #include <trace/hooks/iommu.h>
@@ -282,3 +283,5 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_pagevec_drain);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_zap_pte_range_tlb_start);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_zap_pte_range_tlb_force_flush);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_zap_pte_range_tlb_end);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_bh_lru_install);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_skip_lru_disable);

fs/buffer.c

@@ -51,6 +51,8 @@
 
 #include "internal.h"
 
+#include <trace/hooks/buffer.h>
+
 static int fsync_buffers_list(spinlock_t *lock, struct list_head *list);
 static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,
 			 enum rw_hint hint, struct writeback_control *wbc);
@@ -1233,6 +1235,7 @@ static void bh_lru_install(struct buffer_head *bh)
 	struct buffer_head *evictee = bh;
 	struct bh_lru *b;
 	int i;
+	bool skip = false;
 
 	check_irqs_on();
 	bh_lru_lock();
@@ -1248,6 +1251,12 @@ static void bh_lru_install(struct buffer_head *bh)
 		return;
 	}
 
+	trace_android_vh_bh_lru_install(bh->b_page, &skip);
+	if (skip) {
+		bh_lru_unlock();
+		return;
+	}
+
 	b = this_cpu_ptr(&bh_lrus);
 	for (i = 0; i < BH_LRU_SIZE; i++) {
 		swap(evictee, b->bhs[i]);

include/trace/hooks/buffer.h

@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM buffer
+
+#define TRACE_INCLUDE_PATH trace/hooks
+
+#if !defined(_TRACE_HOOK_BUFFER_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HOOK_BUFFER_H
+
+#include <linux/types.h>
+#include <trace/hooks/vendor_hooks.h>
+
+DECLARE_HOOK(android_vh_bh_lru_install,
+	TP_PROTO(struct page *page, bool *flush),
+	TP_ARGS(page, flush));
+
+/* macro versions of hooks are no longer required */
+
+#endif /* _TRACE_HOOK_BUFFER_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>

include/trace/hooks/mm.h

@@ -89,6 +89,9 @@ DECLARE_HOOK(android_vh_zap_pte_range_tlb_force_flush,
 DECLARE_HOOK(android_vh_zap_pte_range_tlb_end,
 	TP_PROTO(void *ret),
 	TP_ARGS(ret));
+DECLARE_HOOK(android_vh_skip_lru_disable,
+	TP_PROTO(bool *skip),
+	TP_ARGS(skip));
 struct mem_cgroup;
 DECLARE_HOOK(android_vh_mem_cgroup_alloc,
 	TP_PROTO(struct mem_cgroup *memcg),

mm/page_alloc.c

@@ -9153,6 +9153,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
 	unsigned int tries = 0;
 	unsigned int max_tries = 5;
 	int ret = 0;
+	bool skip = false;
 	struct page *page;
 	struct migration_target_control mtc = {
 		.nid = zone_to_nid(cc->zone),
@@ -9162,7 +9163,9 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
 	if (cc->alloc_contig && cc->mode == MIGRATE_ASYNC)
 		max_tries = 1;
 
-	lru_cache_disable();
+	trace_android_vh_skip_lru_disable(&skip);
+	if (!skip)
+		lru_cache_disable();
 
 	while (pfn < end || !list_empty(&cc->migratepages)) {
 		if (fatal_signal_pending(current)) {
@@ -9204,7 +9207,8 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
 			break;
 	}
 
-	lru_cache_enable();
+	if (!skip)
+		lru_cache_enable();
 	if (ret < 0) {
 		if (ret == -EBUSY) {
 			struct page *page;