energy: '__swicth_to' handling refactoring

Change-Id: Id68c9c2fe86197aa6b30517a9cb9a66041896975
Signed-off-by: Vyacheslav Cherkashin <v.cherkashin@samsung.com>

diff --git a/modules/energy/energy.c b/modules/energy/energy.c
index 49ac721d52e727f64753fea7ccaa954144f4adee..e4cf2465f985369168ef0a56d3ae2652b620dae8 100644 (file)
--- a/modules/energy/energy.c
+++ b/modules/energy/energy.c
@@ -391,15 +391,12 @@ static void uninit_data_energy(void)
  * =                             __switch_to                                  =
  * ============================================================================
  */
-static void do_entry_handler_switch(struct task_struct *task)
+static void switch_handler_prev(struct task_struct *task, int cpu)
 {
-       int cpu;
        struct cpus_time *ct;
        struct energy_data *ed;
        unsigned long flags;
 
-       cpu = smp_processor_id();
-
        ct = task->tgid ? &ed_system.ct : &ct_idle;
        cpus_time_lock(ct, flags);
        cpus_time_update_running(ct, cpu, get_ntime(), start_time);
@@ -414,15 +411,12 @@ static void do_entry_handler_switch(struct task_struct *task)
        }
 }
 
-static void do_ret_handler_switch(struct task_struct *task)
+static void switch_handler_next(struct task_struct *task, int cpu)
 {
-       int cpu;
        struct cpus_time *ct;
        struct energy_data *ed;
        unsigned long flags;
 
-       cpu = smp_processor_id();
-
        ct = task->tgid ? &ed_system.ct : &ct_idle;
        cpus_time_lock(ct, flags);
        cpus_time_save_entry(ct, cpu, get_ntime());
@@ -437,18 +431,44 @@ static void do_ret_handler_switch(struct task_struct *task)
        }
 }
 
-#ifndef CONFIG_SWAP_HOOK_SWITCH_TO
+#ifdef CONFIG_SWAP_HOOK_SWITCH_TO
+
+static void handler_switch(struct task_struct *prev,
+                          struct task_struct *next)
+{
+       int cpu = smp_processor_id();
+
+       switch_handler_prev(prev, cpu);
+       switch_handler_next(next, cpu);
+}
+
+static struct swap_hook_ctx switch_to_hook = {
+       .hook = handler_switch
+};
+
+static int switch_to_enable(void)
+{
+       return swap_hook_ctx_reg(&switch_to_hook);
+}
+
+static void switch_to_disable(void)
+{
+       swap_hook_ctx_unreg(&switch_to_hook);
+}
+
+#else /* CONFIG_SWAP_HOOK_SWITCH_TO */
+
 static int ret_handler_switch(struct kretprobe_instance *ri,
                              struct pt_regs *regs)
 {
-       do_ret_handler_switch(current);
+       switch_handler_next(current, smp_processor_id());
        return 0;
 }
 
 static int entry_handler_switch(struct kretprobe_instance *ri,
                                struct pt_regs *regs)
 {
-       do_entry_handler_switch(current);
+       switch_handler_prev(current, smp_processor_id());
        return 0;
 }
 
@@ -456,6 +476,29 @@ static struct kretprobe switch_to_krp = {
        .entry_handler = entry_handler_switch,
        .handler = ret_handler_switch,
 };
+
+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) {
+               pr_err("ERROR: symbol '%s' not found\n", sym);
+               return -ESRCH;
+       }
+
+       return 0;
+}
+
+static int switch_to_enable(void)
+{
+       return swap_register_kretprobe(&switch_to_krp);
+}
+
+static void switch_to_disable(void)
+{
+       swap_unregister_kretprobe(&switch_to_krp);
+}
+
 #endif /* !CONFIG_SWAP_HOOK_SWITCH_TO */
 
 
@@ -1126,26 +1169,13 @@ static struct hook_syscall sys_write_hook = {
 };
 
 
-# ifdef CONFIG_SWAP_HOOK_SWITCH_TO
-static void handler_switch(struct task_struct *prev,
-                          struct task_struct *next)
-{
-       do_entry_handler_switch(prev);
-       do_ret_handler_switch(next);
-}
-
-static struct swap_hook_ctx switch_to_hook = {
-       .hook = handler_switch
-};
-# endif /* CONFIG_SWAP_HOOK_SWITCH_TO */
-
 int do_set_energy(void)
 {
        int ret = 0;
 
        init_data_energy();
 
-       swap_hook_ctx_reg(&switch_to_hook);
+       switch_to_enable();
        ret = swap_td_raw_reg(&sys_call_tdraw, sizeof(struct sys_read_data));
        if (ret)
                return ret;
@@ -1165,7 +1195,7 @@ void do_unset_energy(void)
 {
        /* TODO: uinit lcd */
        swap_hook_energy_unset();
-       swap_hook_ctx_unreg(&switch_to_hook);
+       switch_to_disable();
        hook_syscall_unreg(&sys_write_hook);
        hook_syscall_unreg(&sys_read_hook);
 
@@ -1199,11 +1229,9 @@ int do_set_energy(void)
                goto unregister_sys_read;
        }
 
-       ret = swap_register_kretprobe(&switch_to_krp);
+       ret = switch_to_enable();
        if (ret) {
-               printk(KERN_INFO "swap_register_kretprobe(__switch_to) "
-                      "result=%d!\n",
-                      ret);
+               pr_info("Error __switch_to enable, ret=%d\n", ret);
                goto unregister_sys_write;
        }
 
@@ -1230,7 +1258,7 @@ void do_unset_energy(void)
        energy_xxx_unset(wifi_probes, wifi_probes_cnt, &wifi_flag);
        energy_xxx_unset(bt_probes, bt_probes_cnt, &energy_bt_flag);
 
-       swap_unregister_kretprobe(&switch_to_krp);
+       switch_to_disable();
        swap_unregister_kretprobe(&sys_write_krp);
        swap_unregister_kretprobe(&sys_read_krp);
 
@@ -1239,12 +1267,14 @@ void do_unset_energy(void)
 
 int energy_once(void)
 {
+       int ret;
        const char *sym;
 
-       sym = "__switch_to";
-       switch_to_krp.kp.addr = swap_ksyms(sym);
-       if (switch_to_krp.kp.addr == 0)
-               goto not_found;
+       ret = switch_to_once();
+       if (ret) {
+               pr_err("ERROR: 'switch_to' cannot init, ret=%d\n", ret);
+               return ret;
+       }
 
        sym = "sys_read";
        sys_read_krp.kp.addr = swap_ksyms(sym);