[MIPS] Use conditional traps for BUG_ON on MIPS II and better.

This shaves of around 4kB and a few cycles for the average kernel that
has CONFIG_BUG enabled.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 10 insertions, 4 deletions

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 0ae19e1fa867..2a932cada244 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -669,8 +669,6 @@ asmlinkage void do_bp(struct pt_regs *regs)
         unsigned int opcode, bcode;
         siginfo_t info;
 
-        die_if_kernel("Break instruction in kernel code", regs);
-
         if (get_user(opcode, (unsigned int __user *) exception_epc(regs)))
                 goto out_sigsegv;
 
@@ -693,6 +691,7 @@ asmlinkage void do_bp(struct pt_regs *regs)
         switch (bcode) {
         case BRK_OVERFLOW << 10:
         case BRK_DIVZERO << 10:
+                die_if_kernel("Break instruction in kernel code", regs);
                 if (bcode == (BRK_DIVZERO << 10))
                         info.si_code = FPE_INTDIV;
                 else
@@ -702,7 +701,11 @@ asmlinkage void do_bp(struct pt_regs *regs)
                 info.si_addr = (void __user *) regs->cp0_epc;
                 force_sig_info(SIGFPE, &info, current);
                 break;
+        case BRK_BUG:
+                die("Kernel bug detected", regs);
+                break;
         default:
+                die_if_kernel("Break instruction in kernel code", regs);
                 force_sig(SIGTRAP, current);
         }
 
@@ -715,8 +718,6 @@ asmlinkage void do_tr(struct pt_regs *regs)
         unsigned int opcode, tcode = 0;
         siginfo_t info;
 
-        die_if_kernel("Trap instruction in kernel code", regs);
-
         if (get_user(opcode, (unsigned int __user *) exception_epc(regs)))
                 goto out_sigsegv;
 
@@ -733,6 +734,7 @@ asmlinkage void do_tr(struct pt_regs *regs)
         switch (tcode) {
         case BRK_OVERFLOW:
         case BRK_DIVZERO:
+                die_if_kernel("Trap instruction in kernel code", regs);
                 if (tcode == BRK_DIVZERO)
                         info.si_code = FPE_INTDIV;
                 else
@@ -742,7 +744,11 @@ asmlinkage void do_tr(struct pt_regs *regs)
                 info.si_addr = (void __user *) regs->cp0_epc;
                 force_sig_info(SIGFPE, &info, current);
                 break;
+        case BRK_BUG:
+                die("Kernel bug detected", regs);
+                break;
         default:
+                die_if_kernel("Trap instruction in kernel code", regs);
                 force_sig(SIGTRAP, current);
         }