Commit 35fd219a authored by Suzuki K. Poulose's avatar Suzuki K. Poulose Committed by Benjamin Herrenschmidt
Browse files

powerpc: Move the single step enable code to a generic path 



This patch moves the single step enable code used by kprobe to a generic
routine header so that, it can be re-used by other code, in this case,
uprobes. No functional changes.

Signed-off-by: default avatarSuzuki K. Poulose <suzuki@in.ibm.com>
Cc:	Ananth N Mavinakaynahalli <ananth@in.ibm.com>
Cc:	Kumar Gala <galak@kernel.crashing.org>
Cc:	linuxppc-dev@ozlabs.org
Acked-by: default avatarAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 85f395c5

arch/powerpc/include/asm/probes.h

+25 −0
Original line number Diff line number Diff line
@@ -38,5 +38,30 @@ typedef u32 ppc_opcode_t; 
#define is_trap(instr)		(IS_TW(instr) || IS_TWI(instr))

#endif /* CONFIG_PPC64 */



#ifdef CONFIG_PPC_ADV_DEBUG_REGS

#define MSR_SINGLESTEP	(MSR_DE)

#else

#define MSR_SINGLESTEP	(MSR_SE)

#endif



/* Enable single stepping for the current task */

static inline void enable_single_step(struct pt_regs *regs)

{

	regs->msr |= MSR_SINGLESTEP;

#ifdef CONFIG_PPC_ADV_DEBUG_REGS

	/*

	 * We turn off Critical Input Exception(CE) to ensure that the single

	 * step will be for the instruction we have the probe on; if we don't,

	 * it is possible we'd get the single step reported for CE.

	 */

	regs->msr &= ~MSR_CE;

	mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);

#ifdef CONFIG_PPC_47x

	isync();

#endif

#endif

}





#endif /* __KERNEL__ */

#endif	/* _ASM_POWERPC_PROBES_H */

arch/powerpc/kernel/kprobes.c

+1 −19
Original line number Diff line number Diff line
@@ -36,12 +36,6 @@ 
#include <asm/sstep.h>

#include <asm/uaccess.h>



#ifdef CONFIG_PPC_ADV_DEBUG_REGS

#define MSR_SINGLESTEP	(MSR_DE)

#else

#define MSR_SINGLESTEP	(MSR_SE)

#endif



DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;

DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -104,19 +98,7 @@ void __kprobes arch_remove_kprobe(struct kprobe *p) 


static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs)

{

	regs->msr |= MSR_SINGLESTEP;

#ifdef CONFIG_PPC_ADV_DEBUG_REGS

	/*

	 * We turn off Critical Input Exception(CE) to ensure that the single

	 * step will be for the instruction we have the probe on; if we don't,

	 * it is possible we'd get the single step reported for CE.

	 */

	regs->msr &= ~MSR_CE;

	mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);

#ifdef CONFIG_PPC_47x

	isync();

#endif

#endif

	enable_single_step(regs);



	/*

	 * On powerpc we should single step on the original

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