powerpc/kgdb: use DEFINE_PER_CPU to allocate kgdb's thread_info

Use DEFINE_PER_CPU to allocate thread_info statically instead of kmalloc().
This can avoid introducing more memory check codes.

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
[scottwood@freescale.com: wrapped long line]
Signed-off-by: Scott Wood <scottwood@freescale.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index c1eef241017a..83e89d310734 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -151,15 +151,16 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
         return 1;
 }
 
+static DEFINE_PER_CPU(struct thread_info, kgdb_thread_info);
 static int kgdb_singlestep(struct pt_regs *regs)
 {
         struct thread_info *thread_info, *exception_thread_info;
-        struct thread_info *backup_current_thread_info;
+        struct thread_info *backup_current_thread_info =
+                &__get_cpu_var(kgdb_thread_info);
 
         if (user_mode(regs))
                 return 0;
 
-        backup_current_thread_info = kmalloc(sizeof(struct thread_info), GFP_KERNEL);
         /*
          * On Book E and perhaps other processors, singlestep is handled on
          * the critical exception stack.  This causes current_thread_info()
@@ -185,7 +186,6 @@ static int kgdb_singlestep(struct pt_regs *regs)
                 /* Restore current_thread_info lastly. */
                 memcpy(exception_thread_info, backup_current_thread_info, sizeof *thread_info);
 
-        kfree(backup_current_thread_info);
         return 1;
 }