powerpc/perf: Add support for sampling interrupt register state

The perf infrastructure uses a bit mask to find out valid registers to
display. Define a register mask for supported registers defined in
uapi/asm/perf_regs.h. The bit positions also correspond to register IDs
which is used by perf infrastructure to fetch the register values.
CONFIG_HAVE_PERF_REGS enables sampling of the interrupted machine state.

Signed-off-by: Anju T <anju@linux.vnet.ibm.com>
[mpe: Add license, use CONFIG_PPC64, fix 32-bit build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Anju T 2016-02-20 10:32:46 +05:30 committed by Michael Ellerman
parent 1bfadabfeb
commit ed4a4ef85c
3 changed files with 106 additions and 1 deletions

View File

@ -116,6 +116,7 @@ config PPC
select GENERIC_ATOMIC64 if PPC32
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_HW_BREAKPOINT if PERF_EVENTS && PPC_BOOK3S_64
select ARCH_WANT_IPC_PARSE_VERSION

View File

@ -1,6 +1,6 @@
subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
obj-$(CONFIG_PERF_EVENTS) += callchain.o
obj-$(CONFIG_PERF_EVENTS) += callchain.o perf_regs.o
obj-$(CONFIG_PPC_PERF_CTRS) += core-book3s.o bhrb.o
obj64-$(CONFIG_PPC_PERF_CTRS) += power4-pmu.o ppc970-pmu.o power5-pmu.o \

View File

@ -0,0 +1,104 @@
/*
* Copyright 2016 Anju T, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/perf_event.h>
#include <linux/bug.h>
#include <linux/stddef.h>
#include <asm/ptrace.h>
#include <asm/perf_regs.h>
#define PT_REGS_OFFSET(id, r) [id] = offsetof(struct pt_regs, r)
#define REG_RESERVED (~((1ULL << PERF_REG_POWERPC_MAX) - 1))
static unsigned int pt_regs_offset[PERF_REG_POWERPC_MAX] = {
PT_REGS_OFFSET(PERF_REG_POWERPC_R0, gpr[0]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R1, gpr[1]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R2, gpr[2]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R3, gpr[3]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R4, gpr[4]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R5, gpr[5]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R6, gpr[6]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R7, gpr[7]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R8, gpr[8]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R9, gpr[9]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R10, gpr[10]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R11, gpr[11]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R12, gpr[12]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R13, gpr[13]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R14, gpr[14]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R15, gpr[15]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R16, gpr[16]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R17, gpr[17]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R18, gpr[18]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R19, gpr[19]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R20, gpr[20]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R21, gpr[21]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R22, gpr[22]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R23, gpr[23]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R24, gpr[24]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R25, gpr[25]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R26, gpr[26]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R27, gpr[27]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R28, gpr[28]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R29, gpr[29]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R30, gpr[30]),
PT_REGS_OFFSET(PERF_REG_POWERPC_R31, gpr[31]),
PT_REGS_OFFSET(PERF_REG_POWERPC_NIP, nip),
PT_REGS_OFFSET(PERF_REG_POWERPC_MSR, msr),
PT_REGS_OFFSET(PERF_REG_POWERPC_ORIG_R3, orig_gpr3),
PT_REGS_OFFSET(PERF_REG_POWERPC_CTR, ctr),
PT_REGS_OFFSET(PERF_REG_POWERPC_LINK, link),
PT_REGS_OFFSET(PERF_REG_POWERPC_XER, xer),
PT_REGS_OFFSET(PERF_REG_POWERPC_CCR, ccr),
#ifdef CONFIG_PPC64
PT_REGS_OFFSET(PERF_REG_POWERPC_SOFTE, softe),
#else
PT_REGS_OFFSET(PERF_REG_POWERPC_SOFTE, mq),
#endif
PT_REGS_OFFSET(PERF_REG_POWERPC_TRAP, trap),
PT_REGS_OFFSET(PERF_REG_POWERPC_DAR, dar),
PT_REGS_OFFSET(PERF_REG_POWERPC_DSISR, dsisr),
};
u64 perf_reg_value(struct pt_regs *regs, int idx)
{
if (WARN_ON_ONCE(idx >= PERF_REG_POWERPC_MAX))
return 0;
return regs_get_register(regs, pt_regs_offset[idx]);
}
int perf_reg_validate(u64 mask)
{
if (!mask || mask & REG_RESERVED)
return -EINVAL;
return 0;
}
u64 perf_reg_abi(struct task_struct *task)
{
#ifdef CONFIG_PPC64
if (!test_tsk_thread_flag(task, TIF_32BIT))
return PERF_SAMPLE_REGS_ABI_64;
else
#endif
return PERF_SAMPLE_REGS_ABI_32;
}
void perf_get_regs_user(struct perf_regs *regs_user,
struct pt_regs *regs,
struct pt_regs *regs_user_copy)
{
regs_user->regs = task_pt_regs(current);
regs_user->abi = perf_reg_abi(current);
}