arch/powerpc/include/asm/hw_breakpoint.h

Source file repositories/reference/linux-study-clean/arch/powerpc/include/asm/hw_breakpoint.h

File Facts

System
Linux kernel
Corpus path
arch/powerpc/include/asm/hw_breakpoint.h
Extension
.h
Size
3781 bytes
Lines
129
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct arch_hw_breakpoint {
	unsigned long	address;
	u16		type;
	u16		len; /* length of the target data symbol */
	u16		hw_len; /* length programmed in hw */
	u8		flags;
	bool		perf_single_step; /* temporarily uninstalled for a perf single step */
};

/* Note: Don't change the first 6 bits below as they are in the same order
 * as the dabr and dabrx.
 */
#define HW_BRK_TYPE_READ		0x01
#define HW_BRK_TYPE_WRITE		0x02
#define HW_BRK_TYPE_TRANSLATE		0x04
#define HW_BRK_TYPE_USER		0x08
#define HW_BRK_TYPE_KERNEL		0x10
#define HW_BRK_TYPE_HYP			0x20
#define HW_BRK_TYPE_EXTRANEOUS_IRQ	0x80

/* bits that overlap with the bottom 3 bits of the dabr */
#define HW_BRK_TYPE_RDWR	(HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)
#define HW_BRK_TYPE_DABR	(HW_BRK_TYPE_RDWR | HW_BRK_TYPE_TRANSLATE)
#define HW_BRK_TYPE_PRIV_ALL	(HW_BRK_TYPE_USER | HW_BRK_TYPE_KERNEL | \
				 HW_BRK_TYPE_HYP)

#define HW_BRK_FLAG_DISABLED	0x1

/* Minimum granularity */
#ifdef CONFIG_PPC_8xx
#define HW_BREAKPOINT_SIZE  0x4
#else
#define HW_BREAKPOINT_SIZE  0x8
#endif
#define HW_BREAKPOINT_SIZE_QUADWORD	0x10

#define DABR_MAX_LEN	8
#define DAWR_MAX_LEN	512

static inline int nr_wp_slots(void)
{
	return cpu_has_feature(CPU_FTR_DAWR1) ? 2 : 1;
}

bool wp_check_constraints(struct pt_regs *regs, ppc_inst_t instr,
			  unsigned long ea, int type, int size,
			  struct arch_hw_breakpoint *info);

void wp_get_instr_detail(struct pt_regs *regs, ppc_inst_t *instr,
			 int *type, int *size, unsigned long *ea);

#ifdef CONFIG_HAVE_HW_BREAKPOINT
#include <linux/kdebug.h>
#include <asm/reg.h>
#include <asm/debug.h>

struct perf_event_attr;
struct perf_event;
struct pmu;
struct perf_sample_data;
struct task_struct;

extern int hw_breakpoint_slots(int type);
extern int arch_bp_generic_fields(int type, int *gen_bp_type);
extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
extern int hw_breakpoint_arch_parse(struct perf_event *bp,
				    const struct perf_event_attr *attr,
				    struct arch_hw_breakpoint *hw);
extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
						unsigned long val, void *data);
int arch_install_hw_breakpoint(struct perf_event *bp);
void arch_uninstall_hw_breakpoint(struct perf_event *bp);
void hw_breakpoint_pmu_read(struct perf_event *bp);
extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);

extern struct pmu perf_ops_bp;
extern void ptrace_triggered(struct perf_event *bp,
			struct perf_sample_data *data, struct pt_regs *regs);
static inline void hw_breakpoint_disable(void)
{
	int i;
	struct arch_hw_breakpoint null_brk = {0};

	if (!ppc_breakpoint_available())
		return;

	for (i = 0; i < nr_wp_slots(); i++)
		__set_breakpoint(i, &null_brk);
}
extern void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs);

Annotation

Implementation Notes