debug_core,x86,blackfin: Clean up hw debug disable API

The kgdb_disable_hw_debug() was an architecture specific function for
disabling all hardware breakpoints on a per cpu basis when entering
the debug core.

This patch will remove the weak function kdbg_disable_hw_debug() and
change it into a call back which lives with the rest of hw breakpoint
call backs in struct kgdb_arch.

Signed-off-by: Dongdong Deng <dongdong.deng@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

4 files changed, 10 insertions, 25 deletions

diff --git a/arch/blackfin/kernel/kgdb.c b/arch/blackfin/kernel/kgdb.c
index 08bc44ea6883..edae461b1c54 100644
--- a/arch/blackfin/kernel/kgdb.c
+++ b/arch/blackfin/kernel/kgdb.c
@@ -320,7 +320,7 @@ static void bfin_correct_hw_break(void)
         }
 }
 
-void kgdb_disable_hw_debug(struct pt_regs *regs)
+static void bfin_disable_hw_debug(struct pt_regs *regs)
 {
         /* Disable hardware debugging while we are in kgdb */
         bfin_write_WPIACTL(0);
@@ -406,6 +406,7 @@ struct kgdb_arch arch_kgdb_ops = {
 #endif
         .set_hw_breakpoint = bfin_set_hw_break,
         .remove_hw_breakpoint = bfin_remove_hw_break,
+        .disable_hw_break = bfin_disable_hw_debug,
         .remove_all_hw_break = bfin_remove_all_hw_break,
         .correct_hw_break = bfin_correct_hw_break,
 };
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index d81cfebb848f..ec592caac4b4 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -387,7 +387,7 @@ kgdb_set_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
  *      disable hardware debugging while it is processing gdb packets or
  *      handling exception.
  */
-void kgdb_disable_hw_debug(struct pt_regs *regs)
+static void kgdb_disable_hw_debug(struct pt_regs *regs)
 {
         int i;
         int cpu = raw_smp_processor_id();
@@ -724,6 +724,7 @@ struct kgdb_arch arch_kgdb_ops = {
         .flags                  = KGDB_HW_BREAKPOINT,
         .set_hw_breakpoint      = kgdb_set_hw_break,
         .remove_hw_breakpoint   = kgdb_remove_hw_break,
+        .disable_hw_break       = kgdb_disable_hw_debug,
         .remove_all_hw_break    = kgdb_remove_all_hw_break,
         .correct_hw_break       = kgdb_correct_hw_break,
 };
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index cc96f0f23e04..092e4250a458 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -35,16 +35,6 @@ struct pt_regs;
  */
 extern int kgdb_skipexception(int exception, struct pt_regs *regs);
 
-/**
- *      kgdb_disable_hw_debug - (optional) Disable hardware debugging hook
- *      @regs: Current &struct pt_regs.
- *
- *      This function will be called if the particular architecture must
- *      disable hardware debugging while it is processing gdb packets or
- *      handling exception.
- */
-extern void kgdb_disable_hw_debug(struct pt_regs *regs);
-
 struct tasklet_struct;
 struct task_struct;
 struct uart_port;
@@ -243,6 +233,8 @@ extern void kgdb_arch_late(void);
  * breakpoint.
  * @remove_hw_breakpoint: Allow an architecture to specify how to remove a
  * hardware breakpoint.
+ * @disable_hw_break: Allow an architecture to specify how to disable
+ * hardware breakpoints for a single cpu.
  * @remove_all_hw_break: Allow an architecture to specify how to remove all
  * hardware breakpoints.
  * @correct_hw_break: Allow an architecture to specify how to correct the
@@ -256,6 +248,7 @@ struct kgdb_arch {
         int     (*remove_breakpoint)(unsigned long, char *);
         int     (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
         int     (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
+        void    (*disable_hw_break)(struct pt_regs *regs);
         void    (*remove_all_hw_break)(void);
         void    (*correct_hw_break)(void);
 };
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index fec596da9bd0..cefd4a11f6d9 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -209,18 +209,6 @@ int __weak kgdb_skipexception(int exception, struct pt_regs *regs)
         return 0;
 }
 
-/**
- *      kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
- *      @regs: Current &struct pt_regs.
- *
- *      This function will be called if the particular architecture must
- *      disable hardware debugging while it is processing gdb packets or
- *      handling exception.
- */
-void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
-{
-}
-
 /*
  * Some architectures need cache flushes when we set/clear a
  * breakpoint:
@@ -484,7 +472,9 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs,
                 atomic_inc(&masters_in_kgdb);
         else
                 atomic_inc(&slaves_in_kgdb);
-        kgdb_disable_hw_debug(ks->linux_regs);
+
+        if (arch_kgdb_ops.disable_hw_break)
+                arch_kgdb_ops.disable_hw_break(regs);
 
 acquirelock:
         /*