commit f677efbea129421d02bbba6b5856985f451d08ed
author Suren Baghdasaryan <surenb@google.com> Wed Dec 14 22:08:04 2022 +0000
committer Suren Baghdasaryan <surenb@google.com> Sat Dec 24 12:34:20 2022 -0800
tree d1a14bf2b225de431a08dd3e260799ed699373a7
parent a43cd1f2bb8e2a4b6b1943faccf05198afbbd9e9

Revert "Revert "ANDROID: vendor_hooks:vendor hook for mmput""

This reverts commit 501063ce66dd386c16c47c463c8a3df0e810435f.

Reason for revert: The vendor hook is actually needed by a partner

Bug: 238821038
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I1c19add348792967975369a10ec9cb41fa268236

drivers/android/vendor_hooks.c

diff --git a/drivers/android/vendor_hooks.c b/drivers/android/vendor_hooks.c
index ebcc005..3ff54d2 100644
--- a/drivers/android/vendor_hooks.c
+++ b/drivers/android/vendor_hooks.c
@@ -464,6 +464,7 @@
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_alloc_si);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_free_pages);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_set_shmem_page_flag);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mmput);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_sched_pelt_multiplier);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_alloc_pages_reclaim_bypass);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_alloc_pages_failure_bypass);

include/trace/hooks/sched.h

diff --git a/include/trace/hooks/sched.h b/include/trace/hooks/sched.h
index 6488dee..5f63128 100644
--- a/include/trace/hooks/sched.h
+++ b/include/trace/hooks/sched.h
@@ -391,6 +391,10 @@
 	TP_PROTO(struct task_struct *tsk, int clamp_id, unsigned int value),
 	TP_ARGS(tsk, clamp_id, value));
 
+DECLARE_HOOK(android_vh_mmput,
+	TP_PROTO(void *unused),
+	TP_ARGS(unused));
+
 DECLARE_HOOK(android_vh_sched_pelt_multiplier,
 	TP_PROTO(unsigned int old, unsigned int cur, int *ret),
 	TP_ARGS(old, cur, ret));

kernel/fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index b2ab895..d515aa5 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1150,8 +1150,10 @@
 {
 	might_sleep();
 
-	if (atomic_dec_and_test(&mm->mm_users))
+	if (atomic_dec_and_test(&mm->mm_users)) {
+		trace_android_vh_mmput(NULL);
 		__mmput(mm);
+	}
 }
 EXPORT_SYMBOL_GPL(mmput);