From ea08eeccae9297f7aabd2ef7f0c2517ac4549acc Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:18:26 +0000
Subject: [PATCH] write in 30M
---
kernel/kernel/context_tracking.c | 23 ++++++++++++++---------
1 files changed, 14 insertions(+), 9 deletions(-)
diff --git a/kernel/kernel/context_tracking.c b/kernel/kernel/context_tracking.c
index 9ad37b9..36a98c4 100644
--- a/kernel/kernel/context_tracking.c
+++ b/kernel/kernel/context_tracking.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Context tracking: Probe on high level context boundaries such as kernel
* and userspace. This includes syscalls and exceptions entry/exit.
@@ -24,13 +25,13 @@
#define CREATE_TRACE_POINTS
#include <trace/events/context_tracking.h>
-DEFINE_STATIC_KEY_FALSE(context_tracking_enabled);
-EXPORT_SYMBOL_GPL(context_tracking_enabled);
+DEFINE_STATIC_KEY_FALSE(context_tracking_key);
+EXPORT_SYMBOL_GPL(context_tracking_key);
DEFINE_PER_CPU(struct context_tracking, context_tracking);
EXPORT_SYMBOL_GPL(context_tracking);
-static bool context_tracking_recursion_enter(void)
+static noinstr bool context_tracking_recursion_enter(void)
{
int recursion;
@@ -44,7 +45,7 @@
return false;
}
-static void context_tracking_recursion_exit(void)
+static __always_inline void context_tracking_recursion_exit(void)
{
__this_cpu_dec(context_tracking.recursion);
}
@@ -58,7 +59,7 @@
* instructions to execute won't use any RCU read side critical section
* because this function sets RCU in extended quiescent state.
*/
-void __context_tracking_enter(enum ctx_state state)
+void noinstr __context_tracking_enter(enum ctx_state state)
{
/* Kernel threads aren't supposed to go to userspace */
WARN_ON_ONCE(!current->mm);
@@ -76,8 +77,10 @@
* on the tick.
*/
if (state == CONTEXT_USER) {
+ instrumentation_begin();
trace_user_enter(0);
vtime_user_enter(current);
+ instrumentation_end();
}
rcu_user_enter();
}
@@ -98,7 +101,6 @@
}
context_tracking_recursion_exit();
}
-NOKPROBE_SYMBOL(__context_tracking_enter);
EXPORT_SYMBOL_GPL(__context_tracking_enter);
void context_tracking_enter(enum ctx_state state)
@@ -141,7 +143,7 @@
* This call supports re-entrancy. This way it can be called from any exception
* handler without needing to know if we came from userspace or not.
*/
-void __context_tracking_exit(enum ctx_state state)
+void noinstr __context_tracking_exit(enum ctx_state state)
{
if (!context_tracking_recursion_enter())
return;
@@ -154,15 +156,16 @@
*/
rcu_user_exit();
if (state == CONTEXT_USER) {
+ instrumentation_begin();
vtime_user_exit(current);
trace_user_exit(0);
+ instrumentation_end();
}
}
__this_cpu_write(context_tracking.state, CONTEXT_KERNEL);
}
context_tracking_recursion_exit();
}
-NOKPROBE_SYMBOL(__context_tracking_exit);
EXPORT_SYMBOL_GPL(__context_tracking_exit);
void context_tracking_exit(enum ctx_state state)
@@ -191,17 +194,19 @@
if (!per_cpu(context_tracking.active, cpu)) {
per_cpu(context_tracking.active, cpu) = true;
- static_branch_inc(&context_tracking_enabled);
+ static_branch_inc(&context_tracking_key);
}
if (initialized)
return;
+#ifdef CONFIG_HAVE_TIF_NOHZ
/*
* Set TIF_NOHZ to init/0 and let it propagate to all tasks through fork
* This assumes that init is the only task at this early boot stage.
*/
set_tsk_thread_flag(&init_task, TIF_NOHZ);
+#endif
WARN_ON_ONCE(!tasklist_empty());
initialized = true;
--
Gitblit v1.6.2