linux/arch/x86/include/asm/hw_breakpoint.h
Marco Elver be3f152568 perf/hw_breakpoint: Optimize constant number of breakpoint slots
Optimize internal hw_breakpoint state if the architecture's number of
breakpoint slots is constant. This avoids several kmalloc() calls and
potentially unnecessary failures if the allocations fail, as well as
subtly improves code generation and cache locality.

The protocol is that if an architecture defines hw_breakpoint_slots via
the preprocessor, it must be constant and the same for all types.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20220829124719.675715-7-elver@google.com
2022-08-30 10:56:22 +02:00

78 lines
2.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _I386_HW_BREAKPOINT_H
#define _I386_HW_BREAKPOINT_H
#include <uapi/asm/hw_breakpoint.h>
#define __ARCH_HW_BREAKPOINT_H
/*
* The name should probably be something dealt in
* a higher level. While dealing with the user
* (display/resolving)
*/
struct arch_hw_breakpoint {
unsigned long address;
unsigned long mask;
u8 len;
u8 type;
};
#include <linux/kdebug.h>
#include <linux/percpu.h>
#include <linux/list.h>
/* Available HW breakpoint length encodings */
#define X86_BREAKPOINT_LEN_X 0x40
#define X86_BREAKPOINT_LEN_1 0x40
#define X86_BREAKPOINT_LEN_2 0x44
#define X86_BREAKPOINT_LEN_4 0x4c
#ifdef CONFIG_X86_64
#define X86_BREAKPOINT_LEN_8 0x48
#endif
/* Available HW breakpoint type encodings */
/* trigger on instruction execute */
#define X86_BREAKPOINT_EXECUTE 0x80
/* trigger on memory write */
#define X86_BREAKPOINT_WRITE 0x81
/* trigger on memory read or write */
#define X86_BREAKPOINT_RW 0x83
/* Total number of available HW breakpoint registers */
#define HBP_NUM 4
#define hw_breakpoint_slots(type) (HBP_NUM)
struct perf_event_attr;
struct perf_event;
struct pmu;
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);
void hw_breakpoint_pmu_unthrottle(struct perf_event *bp);
extern void
arch_fill_perf_breakpoint(struct perf_event *bp);
unsigned long encode_dr7(int drnum, unsigned int len, unsigned int type);
int decode_dr7(unsigned long dr7, int bpnum, unsigned *len, unsigned *type);
extern int arch_bp_generic_fields(int x86_len, int x86_type,
int *gen_len, int *gen_type);
extern struct pmu perf_ops_bp;
#endif /* _I386_HW_BREAKPOINT_H */