Revert "ANDROID: vendor_hooks:vendor hook for pidfd_open"

This reverts commit 242b11e574.

The hook android_vh_pidfd_open is not used by any vendor, so remove it
to help with merge issues with future LTS releases.

If this is needed by any real user, it can easily be reverted to add it
back and then the symbol should be added to the abi list at the same
time to prevent it from being removed again later.

Bug: 203756332
Bug: 238725692
Cc: xiaofeng <xiaofeng5@xiaomi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I77afe002bebc3b3e97ea7a28faae74e9cb8a6718

drivers/android/vendor_hooks.c

@@ -445,5 +445,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_account_swap_pages);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_unuse_swap_page);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_si_swapinfo);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_set_shmem_page_flag);
-EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_pidfd_open);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_sched_pelt_multiplier);

include/trace/hooks/sched.h

@@ -391,10 +391,6 @@ DECLARE_HOOK(android_vh_setscheduler_uclamp,
 	TP_PROTO(struct task_struct *tsk, int clamp_id, unsigned int value),
 	TP_ARGS(tsk, clamp_id, value));
 
-DECLARE_HOOK(android_vh_pidfd_open,
-	TP_PROTO(struct pid *p),
-	TP_ARGS(p));
-
 DECLARE_HOOK(android_vh_sched_pelt_multiplier,
 	TP_PROTO(unsigned int old, unsigned int cur, int *ret),
 	TP_ARGS(old, cur, ret));

kernel/pid.c

@@ -45,9 +45,6 @@
 #include <net/sock.h>
 #include <uapi/linux/pidfd.h>
 
-#undef CREATE_TRACE_POINTS
-#include <trace/hooks/sched.h>
-
 struct pid init_struct_pid = {
 	.count		= REFCOUNT_INIT(1),
 	.tasks		= {
@@ -605,7 +602,6 @@ SYSCALL_DEFINE2(pidfd_open, pid_t, pid, unsigned int, flags)
 	else
 		fd = -EINVAL;
 
-	trace_android_vh_pidfd_open(p);
 	put_pid(p);
 	return fd;
 }