energy: use kprobe for __switch_to detecting

Change-Id: I069d8d2427029c6f7452d6d9f198904ebf94ae1e
Signed-off-by: Vyacheslav Cherkashin <v.cherkashin@samsung.com>

diff --git a/modules/energy/energy.c b/modules/energy/energy.c
index e4cf2465f985369168ef0a56d3ae2652b620dae8..67b3da37bf704a093776cd9ee11e28ddb840309a 100644 (file)
--- a/modules/energy/energy.c
+++ b/modules/energy/energy.c
@@ -431,10 +431,7 @@ static void switch_handler_next(struct task_struct *task, int cpu)
        }
 }
 
-#ifdef CONFIG_SWAP_HOOK_SWITCH_TO
-
-static void handler_switch(struct task_struct *prev,
-                          struct task_struct *next)
+static void switch_handler(struct task_struct *prev, struct task_struct *next)
 {
        int cpu = smp_processor_id();
 
@@ -442,8 +439,10 @@ static void handler_switch(struct task_struct *prev,
        switch_handler_next(next, cpu);
 }
 
+#ifdef CONFIG_SWAP_HOOK_SWITCH_TO
+
 static struct swap_hook_ctx switch_to_hook = {
-       .hook = handler_switch
+       .hook = switch_handler
 };
 
 static int switch_to_enable(void)
@@ -458,30 +457,25 @@ static void switch_to_disable(void)
 
 #else /* CONFIG_SWAP_HOOK_SWITCH_TO */
 
-static int ret_handler_switch(struct kretprobe_instance *ri,
-                             struct pt_regs *regs)
+static int kp_switch_handler(struct kprobe *p, struct pt_regs *regs)
 {
-       switch_handler_next(current, smp_processor_id());
-       return 0;
-}
+       struct task_struct *prev = swap_switch_to_prev(regs);
+       struct task_struct *next = swap_switch_to_next(regs);
+
+       switch_handler(prev, next);
 
-static int entry_handler_switch(struct kretprobe_instance *ri,
-                               struct pt_regs *regs)
-{
-       switch_handler_prev(current, smp_processor_id());
        return 0;
 }
 
-static struct kretprobe switch_to_krp = {
-       .entry_handler = entry_handler_switch,
-       .handler = ret_handler_switch,
+static struct kprobe switch_to_kp = {
+       .pre_handler = kp_switch_handler,
 };
 
 static int switch_to_once(void)
 {
        const char *sym = "__switch_to";
-       switch_to_krp.kp.addr = swap_ksyms(sym);
-       if (switch_to_krp.kp.addr == 0) {
+       switch_to_kp.addr = swap_ksyms(sym);
+       if (switch_to_kp.addr == 0) {
                pr_err("ERROR: symbol '%s' not found\n", sym);
                return -ESRCH;
        }
@@ -491,12 +485,12 @@ static int switch_to_once(void)
 
 static int switch_to_enable(void)
 {
-       return swap_register_kretprobe(&switch_to_krp);
+       return swap_register_kprobe(&switch_to_kp);
 }
 
 static void switch_to_disable(void)
 {
-       swap_unregister_kretprobe(&switch_to_krp);
+       swap_unregister_kprobe(&switch_to_kp);
 }
 
 #endif /* !CONFIG_SWAP_HOOK_SWITCH_TO */