freebsd-dev/sys/dev/hwpmc/hwpmc_mips.c
2018-06-08 17:41:49 +00:00

810 lines
17 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2010, George V. Neville-Neil <gnn@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_hwpmc_hooks.h"
#include <sys/param.h>
#include <sys/pmc.h>
#include <sys/pmckern.h>
#include <sys/systm.h>
#include <machine/pmc_mdep.h>
#include <machine/md_var.h>
#include <machine/mips_opcode.h>
#include <machine/vmparam.h>
int mips_npmcs;
/*
* Per-processor information.
*/
struct mips_cpu {
struct pmc_hw *pc_mipspmcs;
};
static struct mips_cpu **mips_pcpu;
#if defined(__mips_n64)
# define MIPS_IS_VALID_KERNELADDR(reg) ((((reg) & 3) == 0) && \
((vm_offset_t)(reg) >= MIPS_XKPHYS_START))
#else
# define MIPS_IS_VALID_KERNELADDR(reg) ((((reg) & 3) == 0) && \
((vm_offset_t)(reg) >= MIPS_KSEG0_START))
#endif
/*
* We need some reasonable default to prevent backtrace code
* from wandering too far
*/
#define MAX_FUNCTION_SIZE 0x10000
#define MAX_PROLOGUE_SIZE 0x100
static int
mips_allocate_pmc(int cpu, int ri, struct pmc *pm,
const struct pmc_op_pmcallocate *a)
{
enum pmc_event pe;
uint32_t caps, config, counter;
uint32_t event;
int i;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] illegal CPU value %d", __LINE__, cpu));
KASSERT(ri >= 0 && ri < mips_npmcs,
("[mips,%d] illegal row index %d", __LINE__, ri));
caps = a->pm_caps;
if (a->pm_class != mips_pmc_spec.ps_cpuclass)
return (EINVAL);
pe = a->pm_ev;
counter = MIPS_CTR_ALL;
event = 0;
for (i = 0; i < mips_event_codes_size; i++) {
if (mips_event_codes[i].pe_ev == pe) {
event = mips_event_codes[i].pe_code;
counter = mips_event_codes[i].pe_counter;
break;
}
}
if (i == mips_event_codes_size)
return (EINVAL);
if ((counter != MIPS_CTR_ALL) && (counter != ri))
return (EINVAL);
config = mips_get_perfctl(cpu, ri, event, caps);
pm->pm_md.pm_mips_evsel = config;
PMCDBG2(MDP,ALL,2,"mips-allocate ri=%d -> config=0x%x", ri, config);
return 0;
}
static int
mips_read_pmc(int cpu, int ri, pmc_value_t *v)
{
struct pmc *pm;
pmc_value_t tmp;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] illegal CPU value %d", __LINE__, cpu));
KASSERT(ri >= 0 && ri < mips_npmcs,
("[mips,%d] illegal row index %d", __LINE__, ri));
pm = mips_pcpu[cpu]->pc_mipspmcs[ri].phw_pmc;
tmp = mips_pmcn_read(ri);
PMCDBG2(MDP,REA,2,"mips-read id=%d -> %jd", ri, tmp);
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
*v = tmp - (1UL << (mips_pmc_spec.ps_counter_width - 1));
else
*v = tmp;
return 0;
}
static int
mips_write_pmc(int cpu, int ri, pmc_value_t v)
{
struct pmc *pm;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] illegal CPU value %d", __LINE__, cpu));
KASSERT(ri >= 0 && ri < mips_npmcs,
("[mips,%d] illegal row-index %d", __LINE__, ri));
pm = mips_pcpu[cpu]->pc_mipspmcs[ri].phw_pmc;
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
v = (1UL << (mips_pmc_spec.ps_counter_width - 1)) - v;
PMCDBG3(MDP,WRI,1,"mips-write cpu=%d ri=%d v=%jx", cpu, ri, v);
mips_pmcn_write(ri, v);
return 0;
}
static int
mips_config_pmc(int cpu, int ri, struct pmc *pm)
{
struct pmc_hw *phw;
PMCDBG3(MDP,CFG,1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] illegal CPU value %d", __LINE__, cpu));
KASSERT(ri >= 0 && ri < mips_npmcs,
("[mips,%d] illegal row-index %d", __LINE__, ri));
phw = &mips_pcpu[cpu]->pc_mipspmcs[ri];
KASSERT(pm == NULL || phw->phw_pmc == NULL,
("[mips,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
__LINE__, pm, phw->phw_pmc));
phw->phw_pmc = pm;
return 0;
}
static int
mips_start_pmc(int cpu, int ri)
{
uint32_t config;
struct pmc *pm;
struct pmc_hw *phw;
phw = &mips_pcpu[cpu]->pc_mipspmcs[ri];
pm = phw->phw_pmc;
config = pm->pm_md.pm_mips_evsel;
/* Enable the PMC. */
switch (ri) {
case 0:
mips_wr_perfcnt0(config);
break;
case 1:
mips_wr_perfcnt2(config);
break;
default:
break;
}
return 0;
}
static int
mips_stop_pmc(int cpu, int ri)
{
struct pmc *pm;
struct pmc_hw *phw;
phw = &mips_pcpu[cpu]->pc_mipspmcs[ri];
pm = phw->phw_pmc;
/*
* Disable the PMCs.
*
* Clearing the entire register turns the counter off as well
* as removes the previously sampled event.
*/
switch (ri) {
case 0:
mips_wr_perfcnt0(0);
break;
case 1:
mips_wr_perfcnt2(0);
break;
default:
break;
}
return 0;
}
static int
mips_release_pmc(int cpu, int ri, struct pmc *pmc)
{
struct pmc_hw *phw;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] illegal CPU value %d", __LINE__, cpu));
KASSERT(ri >= 0 && ri < mips_npmcs,
("[mips,%d] illegal row-index %d", __LINE__, ri));
phw = &mips_pcpu[cpu]->pc_mipspmcs[ri];
KASSERT(phw->phw_pmc == NULL,
("[mips,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
return 0;
}
static int
mips_pmc_intr(struct trapframe *tf)
{
int error;
int retval, ri, cpu;
struct pmc *pm;
struct mips_cpu *pc;
uint32_t r0, r2;
pmc_value_t r;
cpu = curcpu;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] CPU %d out of range", __LINE__, cpu));
retval = 0;
pc = mips_pcpu[cpu];
/* Stop PMCs without clearing the counter */
r0 = mips_rd_perfcnt0();
mips_wr_perfcnt0(r0 & ~(0x1f));
r2 = mips_rd_perfcnt2();
mips_wr_perfcnt2(r2 & ~(0x1f));
for (ri = 0; ri < mips_npmcs; ri++) {
pm = mips_pcpu[cpu]->pc_mipspmcs[ri].phw_pmc;
if (pm == NULL)
continue;
if (! PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
continue;
r = mips_pmcn_read(ri);
/* If bit 31 is set, the counter has overflowed */
if ((r & (1UL << (mips_pmc_spec.ps_counter_width - 1))) == 0)
continue;
retval = 1;
if (pm->pm_state != PMC_STATE_RUNNING)
continue;
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error) {
/* Clear/disable the relevant counter */
if (ri == 0)
r0 = 0;
else if (ri == 1)
r2 = 0;
mips_stop_pmc(cpu, ri);
}
/* Reload sampling count */
mips_write_pmc(cpu, ri, pm->pm_sc.pm_reloadcount);
}
/*
* Re-enable the PMC counters where they left off.
*
* Any counter which overflowed will have its sample count
* reloaded in the loop above.
*/
mips_wr_perfcnt0(r0);
mips_wr_perfcnt2(r2);
return retval;
}
static int
mips_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
{
int error;
struct pmc_hw *phw;
char mips_name[PMC_NAME_MAX];
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d], illegal CPU %d", __LINE__, cpu));
KASSERT(ri >= 0 && ri < mips_npmcs,
("[mips,%d] row-index %d out of range", __LINE__, ri));
phw = &mips_pcpu[cpu]->pc_mipspmcs[ri];
snprintf(mips_name, sizeof(mips_name), "MIPS-%d", ri);
if ((error = copystr(mips_name, pi->pm_name, PMC_NAME_MAX,
NULL)) != 0)
return error;
pi->pm_class = mips_pmc_spec.ps_cpuclass;
if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
pi->pm_enabled = TRUE;
*ppmc = phw->phw_pmc;
} else {
pi->pm_enabled = FALSE;
*ppmc = NULL;
}
return (0);
}
static int
mips_get_config(int cpu, int ri, struct pmc **ppm)
{
*ppm = mips_pcpu[cpu]->pc_mipspmcs[ri].phw_pmc;
return 0;
}
/*
* XXX don't know what we should do here.
*/
static int
mips_pmc_switch_in(struct pmc_cpu *pc, struct pmc_process *pp)
{
return 0;
}
static int
mips_pmc_switch_out(struct pmc_cpu *pc, struct pmc_process *pp)
{
return 0;
}
static int
mips_pcpu_init(struct pmc_mdep *md, int cpu)
{
int first_ri, i;
struct pmc_cpu *pc;
struct mips_cpu *pac;
struct pmc_hw *phw;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[mips,%d] wrong cpu number %d", __LINE__, cpu));
PMCDBG1(MDP,INI,1,"mips-init cpu=%d", cpu);
mips_pcpu[cpu] = pac = malloc(sizeof(struct mips_cpu), M_PMC,
M_WAITOK|M_ZERO);
pac->pc_mipspmcs = malloc(sizeof(struct pmc_hw) * mips_npmcs,
M_PMC, M_WAITOK|M_ZERO);
pc = pmc_pcpu[cpu];
first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_MIPS].pcd_ri;
KASSERT(pc != NULL, ("[mips,%d] NULL per-cpu pointer", __LINE__));
for (i = 0, phw = pac->pc_mipspmcs; i < mips_npmcs; i++, phw++) {
phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
phw->phw_pmc = NULL;
pc->pc_hwpmcs[i + first_ri] = phw;
}
/*
* Clear the counter control register which has the effect
* of disabling counting.
*/
for (i = 0; i < mips_npmcs; i++)
mips_pmcn_write(i, 0);
return 0;
}
static int
mips_pcpu_fini(struct pmc_mdep *md, int cpu)
{
return 0;
}
struct pmc_mdep *
pmc_mips_initialize()
{
struct pmc_mdep *pmc_mdep;
struct pmc_classdep *pcd;
/*
* TODO: Use More bit of PerfCntlX register to detect actual
* number of counters
*/
mips_npmcs = 2;
PMCDBG1(MDP,INI,1,"mips-init npmcs=%d", mips_npmcs);
/*
* Allocate space for pointers to PMC HW descriptors and for
* the MDEP structure used by MI code.
*/
mips_pcpu = malloc(sizeof(struct mips_cpu *) * pmc_cpu_max(), M_PMC,
M_WAITOK|M_ZERO);
/* Just one class */
pmc_mdep = pmc_mdep_alloc(1);
pmc_mdep->pmd_cputype = mips_pmc_spec.ps_cputype;
pcd = &pmc_mdep->pmd_classdep[PMC_MDEP_CLASS_INDEX_MIPS];
pcd->pcd_caps = mips_pmc_spec.ps_capabilities;
pcd->pcd_class = mips_pmc_spec.ps_cpuclass;
pcd->pcd_num = mips_npmcs;
pcd->pcd_ri = pmc_mdep->pmd_npmc;
pcd->pcd_width = mips_pmc_spec.ps_counter_width;
pcd->pcd_allocate_pmc = mips_allocate_pmc;
pcd->pcd_config_pmc = mips_config_pmc;
pcd->pcd_pcpu_fini = mips_pcpu_fini;
pcd->pcd_pcpu_init = mips_pcpu_init;
pcd->pcd_describe = mips_describe;
pcd->pcd_get_config = mips_get_config;
pcd->pcd_read_pmc = mips_read_pmc;
pcd->pcd_release_pmc = mips_release_pmc;
pcd->pcd_start_pmc = mips_start_pmc;
pcd->pcd_stop_pmc = mips_stop_pmc;
pcd->pcd_write_pmc = mips_write_pmc;
pmc_mdep->pmd_intr = mips_pmc_intr;
pmc_mdep->pmd_switch_in = mips_pmc_switch_in;
pmc_mdep->pmd_switch_out = mips_pmc_switch_out;
pmc_mdep->pmd_npmc += mips_npmcs;
return (pmc_mdep);
}
void
pmc_mips_finalize(struct pmc_mdep *md)
{
(void) md;
}
#ifdef HWPMC_MIPS_BACKTRACE
static int
pmc_next_frame(register_t *pc, register_t *sp)
{
InstFmt i;
uintptr_t va;
uint32_t instr, mask;
int more, stksize;
register_t ra = 0;
/* Jump here after a nonstandard (interrupt handler) frame */
stksize = 0;
/* check for bad SP: could foul up next frame */
if (!MIPS_IS_VALID_KERNELADDR(*sp)) {
goto error;
}
/* check for bad PC */
if (!MIPS_IS_VALID_KERNELADDR(*pc)) {
goto error;
}
/*
* Find the beginning of the current subroutine by scanning
* backwards from the current PC for the end of the previous
* subroutine.
*/
va = *pc - sizeof(int);
while (1) {
instr = *((uint32_t *)va);
/* [d]addiu sp,sp,-X */
if (((instr & 0xffff8000) == 0x27bd8000)
|| ((instr & 0xffff8000) == 0x67bd8000))
break;
/* jr ra */
if (instr == 0x03e00008) {
/* skip over branch-delay slot instruction */
va += 2 * sizeof(int);
break;
}
va -= sizeof(int);
}
/* skip over nulls which might separate .o files */
while ((instr = *((uint32_t *)va)) == 0)
va += sizeof(int);
/* scan forwards to find stack size and any saved registers */
stksize = 0;
more = 3;
mask = 0;
for (; more; va += sizeof(int),
more = (more == 3) ? 3 : more - 1) {
/* stop if hit our current position */
if (va >= *pc)
break;
instr = *((uint32_t *)va);
i.word = instr;
switch (i.JType.op) {
case OP_SPECIAL:
switch (i.RType.func) {
case OP_JR:
case OP_JALR:
more = 2; /* stop after next instruction */
break;
case OP_SYSCALL:
case OP_BREAK:
more = 1; /* stop now */
}
break;
case OP_BCOND:
case OP_J:
case OP_JAL:
case OP_BEQ:
case OP_BNE:
case OP_BLEZ:
case OP_BGTZ:
more = 2; /* stop after next instruction */
break;
case OP_COP0:
case OP_COP1:
case OP_COP2:
case OP_COP3:
switch (i.RType.rs) {
case OP_BCx:
case OP_BCy:
more = 2; /* stop after next instruction */
}
break;
case OP_SW:
case OP_SD:
/*
* SP is being saved using S8(FP). Most likely it indicates
* that SP is modified in the function and we can't get
* its value safely without emulating code backward
* So just bail out on functions like this
*/
if ((i.IType.rs == 30) && (i.IType.rt = 29))
return (-1);
/* look for saved registers on the stack */
if (i.IType.rs != 29)
break;
/* only restore the first one */
if (mask & (1 << i.IType.rt))
break;
mask |= (1 << i.IType.rt);
if (i.IType.rt == 31)
ra = *((register_t *)(*sp + (short)i.IType.imm));
break;
case OP_ADDI:
case OP_ADDIU:
case OP_DADDI:
case OP_DADDIU:
/* look for stack pointer adjustment */
if (i.IType.rs != 29 || i.IType.rt != 29)
break;
stksize = -((short)i.IType.imm);
}
}
if (!MIPS_IS_VALID_KERNELADDR(ra))
return (-1);
*pc = ra;
*sp += stksize;
return (0);
error:
return (-1);
}
static int
pmc_next_uframe(register_t *pc, register_t *sp, register_t *ra)
{
int offset, registers_on_stack;
uint32_t opcode, mask;
register_t function_start;
int stksize;
InstFmt i;
registers_on_stack = 0;
mask = 0;
function_start = 0;
offset = 0;
stksize = 0;
while (offset < MAX_FUNCTION_SIZE) {
opcode = fuword32((void *)(*pc - offset));
/* [d]addiu sp, sp, -X*/
if (((opcode & 0xffff8000) == 0x27bd8000)
|| ((opcode & 0xffff8000) == 0x67bd8000)) {
function_start = *pc - offset;
registers_on_stack = 1;
break;
}
/* lui gp, X */
if ((opcode & 0xffff8000) == 0x3c1c0000) {
/*
* Function might start with this instruction
* Keep an eye on "jr ra" and sp correction
* with positive value further on
*/
function_start = *pc - offset;
}
if (function_start) {
/*
* Stop looking further. Possible end of
* function instruction: it means there is no
* stack modifications, sp is unchanged
*/
/* [d]addiu sp,sp,X */
if (((opcode & 0xffff8000) == 0x27bd0000)
|| ((opcode & 0xffff8000) == 0x67bd0000))
break;
if (opcode == 0x03e00008)
break;
}
offset += sizeof(int);
}
if (!function_start)
return (-1);
if (registers_on_stack) {
offset = 0;
while ((offset < MAX_PROLOGUE_SIZE)
&& ((function_start + offset) < *pc)) {
i.word = fuword32((void *)(function_start + offset));
switch (i.JType.op) {
case OP_SW:
/* look for saved registers on the stack */
if (i.IType.rs != 29)
break;
/* only restore the first one */
if (mask & (1 << i.IType.rt))
break;
mask |= (1 << i.IType.rt);
if (i.IType.rt == 31)
*ra = fuword32((void *)(*sp + (short)i.IType.imm));
break;
#if defined(__mips_n64)
case OP_SD:
/* look for saved registers on the stack */
if (i.IType.rs != 29)
break;
/* only restore the first one */
if (mask & (1 << i.IType.rt))
break;
mask |= (1 << i.IType.rt);
/* ra */
if (i.IType.rt == 31)
*ra = fuword64((void *)(*sp + (short)i.IType.imm));
break;
#endif
case OP_ADDI:
case OP_ADDIU:
case OP_DADDI:
case OP_DADDIU:
/* look for stack pointer adjustment */
if (i.IType.rs != 29 || i.IType.rt != 29)
break;
stksize = -((short)i.IType.imm);
}
offset += sizeof(int);
}
}
/*
* We reached the end of backtrace
*/
if (*pc == *ra)
return (-1);
*pc = *ra;
*sp += stksize;
return (0);
}
#endif /* HWPMC_MIPS_BACKTRACE */
struct pmc_mdep *
pmc_md_initialize()
{
return pmc_mips_initialize();
}
void
pmc_md_finalize(struct pmc_mdep *md)
{
return pmc_mips_finalize(md);
}
int
pmc_save_kernel_callchain(uintptr_t *cc, int nframes,
struct trapframe *tf)
{
register_t pc, ra, sp;
int frames = 0;
pc = tf->pc;
sp = tf->sp;
ra = tf->ra;
cc[frames++] = pc;
#ifdef HWPMC_MIPS_BACKTRACE
/*
* Unwind, and unwind, and unwind
*/
while (1) {
if (frames >= nframes)
break;
if (pmc_next_frame(&pc, &sp) < 0)
break;
cc[frames++] = pc;
}
#endif
return (frames);
}
int
pmc_save_user_callchain(uintptr_t *cc, int nframes,
struct trapframe *tf)
{
register_t pc, ra, sp;
int frames = 0;
pc = tf->pc;
sp = tf->sp;
ra = tf->ra;
cc[frames++] = pc;
#ifdef HWPMC_MIPS_BACKTRACE
/*
* Unwind, and unwind, and unwind
*/
while (1) {
if (frames >= nframes)
break;
if (pmc_next_uframe(&pc, &sp, &ra) < 0)
break;
cc[frames++] = pc;
}
#endif
return (frames);
}