Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

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

Browse source 
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>
This commit is contained in:
Ralf Baechle 2006-10-16 01:38:50 +01:00
parent 005985609f
commit 63dc68a8cf
3 changed files with 22 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
arch/mips/kernel/traps.c
View file

@ -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);
}

12
include/asm-mips/bug.h
View file

@ -1,6 +1,7 @@
#ifndef __ASM_BUG_H
#define __ASM_BUG_H
#include <asm/sgidefs.h>
#ifdef CONFIG_BUG
@ -13,6 +14,17 @@ do { \
#define HAVE_ARCH_BUG
#if (_MIPS_ISA > _MIPS_ISA_MIPS1)
#define BUG_ON(condition) \
do { \
__asm__ __volatile__("tne $0, %0" : : "r" (condition)); \
} while (0)
#define HAVE_ARCH_BUG_ON
#endif /* _MIPS_ISA > _MIPS_ISA_MIPS1 */
#endif
#include <asm-generic/bug.h>

2
include/asm-mips/ptrace.h
View file

@ -80,8 +80,6 @@ struct pt_regs {
#define instruction_pointer(regs) ((regs)->cp0_epc)
#define profile_pc(regs) instruction_pointer(regs)
extern void show_regs(struct pt_regs *);
extern asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit);
#endif