ANDROID: vendor_hooks: FPSIMD save/restore by using vendor_hooks

- To use fpsimd in kernel task, vendor_hook call is needed to
  save/restore fpsimd at scheduling time.
- ANDROID_VENDOR_DATA added to thread_struct.
- Vendor_hooks is called when thread is switching for save/restore
  fpsimd states.
  (trace_android_vh_is_fpsimd_save(prev, next))

This patch was previously in android-mainline, but was reverted
due to conflicts in the 6.2-rc1 merge (aosp/2365029). Adding back.

Bug: 149632552
Bug: 313805669

Change-Id: Ibaa13484d1251fc53c304972f46e8e8a2c1df7fa
Signed-off-by: Wooyeon Kim <wooy88.kim@samsung.com>
Signed-off-by: Jing-Ting Wu <Jing-Ting.Wu@mediatek.com>

arch/arm64/include/asm/processor.h

@@ -31,6 +31,7 @@
 #include <linux/stddef.h>
 #include <linux/string.h>
 #include <linux/thread_info.h>
+#include <linux/android_vendor.h>
 
 #include <vdso/processor.h>
 
@@ -184,6 +185,7 @@ struct thread_struct {
 	u64			sctlr_user;
 	u64			svcr;
 	u64			tpidr2_el0;
+	ANDROID_VENDOR_DATA(1);
 };
 
 static inline unsigned int thread_get_vl(struct thread_struct *thread,

arch/arm64/kernel/process.c

@@ -42,6 +42,7 @@
 #include <linux/prctl.h>
 #include <linux/stacktrace.h>
 #include <trace/hooks/mpam.h>
+#include <trace/hooks/fpsimd.h>
 
 #include <asm/alternative.h>
 #include <asm/compat.h>
@@ -557,6 +558,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
 	if (prev->thread.sctlr_user != next->thread.sctlr_user)
 		update_sctlr_el1(next->thread.sctlr_user);
 
+	trace_android_vh_is_fpsimd_save(prev, next);
+
 	/* the actual thread switch */
 	last = cpu_switch_to(prev, next);
 

drivers/android/vendor_hooks.c

@@ -34,6 +34,7 @@
 #include <trace/hooks/gic_v3.h>
 #include <trace/hooks/remoteproc.h>
 #include <trace/hooks/timer.h>
+#include <trace/hooks/fpsimd.h>
 
 /*
  * Export tracepoints that act as a bare tracehook (ie: have no trace event
@@ -90,3 +91,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_check_bpf_syscall);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_rproc_recovery);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_rproc_recovery_set);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_timer_calc_index);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_is_fpsimd_save);

include/trace/hooks/fpsimd.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM fpsimd
+
+#define TRACE_INCLUDE_PATH trace/hooks
+
+#if !defined(_TRACE_HOOK_FPSIMD_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HOOK_FPSIMD_H
+
+#include <trace/hooks/vendor_hooks.h>
+
+struct task_struct;
+
+DECLARE_HOOK(android_vh_is_fpsimd_save,
+	TP_PROTO(struct task_struct *prev, struct task_struct *next),
+	TP_ARGS(prev, next))
+
+#endif /* _TRACE_HOOK_FPSIMD_H */
+/* This part must be outside protection */
+#include <trace/define_trace.h>