Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git...

[cascardo/linux.git] / arch / arm64 / kernel / hw_breakpoint.c

diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index 26a6bf7..948b731 100644 (file)
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -857,7 +857,7 @@ void hw_breakpoint_thread_switch(struct task_struct *next)
 /*
  * CPU initialisation.
  */
-static void hw_breakpoint_reset(void *unused)
+static int hw_breakpoint_reset(unsigned int cpu)
 {
        int i;
        struct perf_event **slots;
@@ -888,28 +888,14 @@ static void hw_breakpoint_reset(void *unused)
                        write_wb_reg(AARCH64_DBG_REG_WVR, i, 0UL);
                }
        }
-}
 
-static int hw_breakpoint_reset_notify(struct notifier_block *self,
-                                               unsigned long action,
-                                               void *hcpu)
-{
-       if ((action & ~CPU_TASKS_FROZEN) == CPU_ONLINE) {
-               local_irq_disable();
-               hw_breakpoint_reset(NULL);
-               local_irq_enable();
-       }
-       return NOTIFY_OK;
+       return 0;
 }
 
-static struct notifier_block hw_breakpoint_reset_nb = {
-       .notifier_call = hw_breakpoint_reset_notify,
-};
-
 #ifdef CONFIG_CPU_PM
-extern void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *));
+extern void cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int));
 #else
-static inline void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
+static inline void cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int))
 {
 }
 #endif
@@ -919,36 +905,34 @@ static inline void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
  */
 static int __init arch_hw_breakpoint_init(void)
 {
+       int ret;
+
        core_num_brps = get_num_brps();
        core_num_wrps = get_num_wrps();
 
        pr_info("found %d breakpoint and %d watchpoint registers.\n",
                core_num_brps, core_num_wrps);
 
-       cpu_notifier_register_begin();
-
-       /*
-        * Reset the breakpoint resources. We assume that a halting
-        * debugger will leave the world in a nice state for us.
-        */
-       smp_call_function(hw_breakpoint_reset, NULL, 1);
-       hw_breakpoint_reset(NULL);
-
        /* Register debug fault handlers. */
        hook_debug_fault_code(DBG_ESR_EVT_HWBP, breakpoint_handler, SIGTRAP,
                              TRAP_HWBKPT, "hw-breakpoint handler");
        hook_debug_fault_code(DBG_ESR_EVT_HWWP, watchpoint_handler, SIGTRAP,
                              TRAP_HWBKPT, "hw-watchpoint handler");
 
-       /* Register hotplug notifier. */
-       __register_cpu_notifier(&hw_breakpoint_reset_nb);
-
-       cpu_notifier_register_done();
+       /*
+        * Reset the breakpoint resources. We assume that a halting
+        * debugger will leave the world in a nice state for us.
+        */
+       ret = cpuhp_setup_state(CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,
+                         "CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING",
+                         hw_breakpoint_reset, NULL);
+       if (ret)
+               pr_err("failed to register CPU hotplug notifier: %d\n", ret);
 
        /* Register cpu_suspend hw breakpoint restore hook */
        cpu_suspend_set_dbg_restorer(hw_breakpoint_reset);
 
-       return 0;
+       return ret;
 }
 arch_initcall(arch_hw_breakpoint_init);