ANDROID: tracing: Add restricted vendor hooks for preemptirq events

We have debug infrastructure built on top of preempt/irq disable/enable
events. This requires modifications to the kernel tracing code. Since
this is not feasible with GKI, we started with registering to the
existing preemptirq trace events. However the performance of wide
variety of use cases are regressed as the rate of preemptirq events
is super high and generic trace events are slow.

Since GKI allows optimized trace events via restricted trace hooks,
add the same for preemptirq event.

This patch reverts commit d94fa9dcf5, which itself was a revert, effectively bringing back the original
change (Ic8d3cdd1c1aa6a9267d0b755694fedffa2ea8e36)

Bug: 174541725
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Sai Harshini Nimmala <quic_snimmala@quicinc.com>
Change-Id: I24a3cdf17abf41e7512438516b2cfe561802c666
[jstultz: Reworked commit message]
Signed-off-by: John Stultz <jstultz@google.com>

drivers/android/vendor_hooks.c

@@ -19,6 +19,7 @@
 #include <trace/hooks/printk.h>
 #include <trace/hooks/epoch.h>
 #include <trace/hooks/cpufreq.h>
+#include <trace/hooks/preemptirq.h>
 #include <trace/hooks/ufshcd.h>
 #include <trace/hooks/cgroup.h>
 #include <trace/hooks/sys.h>
@@ -78,6 +79,10 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_cpufreq_online);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_cpufreq_resolve_freq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_cpufreq_fast_switch);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_cpufreq_target);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_preempt_disable);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_preempt_enable);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_irqs_disable);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_irqs_enable);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_cpu_cgroup_attach);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_cpu_cgroup_online);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_ufs_fill_prdt);

include/trace/hooks/preemptirq.h

@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM preemptirq
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH trace/hooks
+
+#if !defined(_TRACE_HOOK_PREEMPTIRQ_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HOOK_PREEMPTIRQ_H
+
+#include <trace/hooks/vendor_hooks.h>
+
+DECLARE_RESTRICTED_HOOK(android_rvh_preempt_disable,
+	TP_PROTO(unsigned long ip, unsigned long parent_ip),
+	TP_ARGS(ip, parent_ip), 1);
+
+DECLARE_RESTRICTED_HOOK(android_rvh_preempt_enable,
+	TP_PROTO(unsigned long ip, unsigned long parent_ip),
+	TP_ARGS(ip, parent_ip), 1);
+
+DECLARE_RESTRICTED_HOOK(android_rvh_irqs_disable,
+	TP_PROTO(unsigned long ip, unsigned long parent_ip),
+	TP_ARGS(ip, parent_ip), 1);
+
+DECLARE_RESTRICTED_HOOK(android_rvh_irqs_enable,
+	TP_PROTO(unsigned long ip, unsigned long parent_ip),
+	TP_ARGS(ip, parent_ip), 1);
+
+#endif /* _TRACE_HOOK_PREEMPTIRQ_H */
+/* This part must be outside protection */
+#include <trace/define_trace.h>

kernel/trace/trace_preemptirq.c

@@ -14,6 +14,8 @@
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/preemptirq.h>
+#undef CREATE_TRACE_POINTS
+#include <trace/hooks/preemptirq.h>
 
 /*
  * Use regular trace points on architectures that implement noinstr
@@ -43,6 +45,10 @@ void trace_hardirqs_on_prepare(void)
 {
 	if (this_cpu_read(tracing_irq_cpu)) {
 		trace(irq_enable)(CALLER_ADDR0, CALLER_ADDR1);
+		if (!in_nmi()) {
+			trace_android_rvh_irqs_enable(CALLER_ADDR0,
+						      CALLER_ADDR1);
+		}
 		tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1);
 		this_cpu_write(tracing_irq_cpu, 0);
 	}
@@ -54,6 +60,10 @@ void trace_hardirqs_on(void)
 {
 	if (this_cpu_read(tracing_irq_cpu)) {
 		trace(irq_enable)(CALLER_ADDR0, CALLER_ADDR1);
+		if (!in_nmi()) {
+			trace_android_rvh_irqs_enable(CALLER_ADDR0,
+						      CALLER_ADDR1);
+		}
 		tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1);
 		this_cpu_write(tracing_irq_cpu, 0);
 	}
@@ -76,6 +86,10 @@ void trace_hardirqs_off_finish(void)
 		this_cpu_write(tracing_irq_cpu, 1);
 		tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1);
 		trace(irq_disable)(CALLER_ADDR0, CALLER_ADDR1);
+		if (!in_nmi()) {
+			trace_android_rvh_irqs_disable(CALLER_ADDR0,
+						       CALLER_ADDR1);
+		}
 	}
 
 }
@@ -90,6 +104,10 @@ void trace_hardirqs_off(void)
 		this_cpu_write(tracing_irq_cpu, 1);
 		tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1);
 		trace(irq_disable)(CALLER_ADDR0, CALLER_ADDR1);
+		if (!in_nmi()) {
+			trace_android_rvh_irqs_disable(CALLER_ADDR0,
+						       CALLER_ADDR1);
+		}
 	}
 }
 EXPORT_SYMBOL(trace_hardirqs_off);
@@ -101,12 +119,18 @@ NOKPROBE_SYMBOL(trace_hardirqs_off);
 void trace_preempt_on(unsigned long a0, unsigned long a1)
 {
 	trace(preempt_enable)(a0, a1);
+	if (!in_nmi()) {
+		trace_android_rvh_preempt_enable(a0, a1);
+	}
 	tracer_preempt_on(a0, a1);
 }
 
 void trace_preempt_off(unsigned long a0, unsigned long a1)
 {
 	trace(preempt_disable)(a0, a1);
+	if (!in_nmi()) {
+		trace_android_rvh_preempt_disable(a0, a1);
+	}
 	tracer_preempt_off(a0, a1);
 }
 #endif