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/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#define _GNU_SOURCE /* For CPU_ZERO etc. */
#include <sched.h>
#include <sys/wait.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include "trace.h"
#include "reg.h"
#include "ebb.h"
void (*ebb_user_func)(void);
void ebb_hook(void)
{
if (ebb_user_func)
ebb_user_func();
}
struct ebb_state ebb_state;
u64 sample_period = 0x40000000ull;
void reset_ebb_with_clear_mask(unsigned long mmcr0_clear_mask)
{
u64 val;
/* 2) clear MMCR0[PMAO] - docs say BESCR[PMEO] should do this */
/* 3) set MMCR0[PMAE] - docs say BESCR[PME] should do this */
val = mfspr(SPRN_MMCR0);
mtspr(SPRN_MMCR0, (val & ~mmcr0_clear_mask) | MMCR0_PMAE);
/* 4) clear BESCR[PMEO] */
mtspr(SPRN_BESCRR, BESCR_PMEO);
/* 5) set BESCR[PME] */
mtspr(SPRN_BESCRS, BESCR_PME);
/* 6) rfebb 1 - done in our caller */
}
void reset_ebb(void)
{
reset_ebb_with_clear_mask(MMCR0_PMAO | MMCR0_FC);
}
/* Called outside of the EBB handler to check MMCR0 is sane */
int ebb_check_mmcr0(void)
{
u64 val;
val = mfspr(SPRN_MMCR0);
if ((val & (MMCR0_FC | MMCR0_PMAO)) == MMCR0_FC) {
/* It's OK if we see FC & PMAO, but not FC by itself */
printf("Outside of loop, only FC set 0x%llx\n", val);
return 1;
}
return 0;
}
bool ebb_check_count(int pmc, u64 sample_period, int fudge)
{
u64 count, upper, lower;
count = ebb_state.stats.pmc_count[PMC_INDEX(pmc)];
lower = ebb_state.stats.ebb_count * (sample_period - fudge);
if (count < lower) {
printf("PMC%d count (0x%llx) below lower limit 0x%llx (-0x%llx)\n",
pmc, count, lower, lower - count);
return false;
}
upper = ebb_state.stats.ebb_count * (sample_period + fudge);
if (count > upper) {
printf("PMC%d count (0x%llx) above upper limit 0x%llx (+0x%llx)\n",
pmc, count, upper, count - upper);
return false;
}
printf("PMC%d count (0x%llx) is between 0x%llx and 0x%llx delta +0x%llx/-0x%llx\n",
pmc, count, lower, upper, count - lower, upper - count);
return true;
}
void standard_ebb_callee(void)
{
int found, i;
u64 val;
val = mfspr(SPRN_BESCR);
if (!(val & BESCR_PMEO)) {
ebb_state.stats.spurious++;
goto out;
}
ebb_state.stats.ebb_count++;
trace_log_counter(ebb_state.trace, ebb_state.stats.ebb_count);
val = mfspr(SPRN_MMCR0);
trace_log_reg(ebb_state.trace, SPRN_MMCR0, val);
found = 0;
for (i = 1; i <= 6; i++) {
if (ebb_state.pmc_enable[PMC_INDEX(i)])
found += count_pmc(i, sample_period);
}
if (!found)
ebb_state.stats.no_overflow++;
out:
reset_ebb();
}
extern void ebb_handler(void);
void setup_ebb_handler(void (*callee)(void))
{
u64 entry;
#if defined(_CALL_ELF) && _CALL_ELF == 2
entry = (u64)ebb_handler;
#else
struct opd
{
u64 entry;
u64 toc;
} *opd;
opd = (struct opd *)ebb_handler;
entry = opd->entry;
#endif
printf("EBB Handler is at %#llx\n", entry);
ebb_user_func = callee;
/* Ensure ebb_user_func is set before we set the handler */
mb();
mtspr(SPRN_EBBHR, entry);
/* Make sure the handler is set before we return */
mb();
}
void clear_ebb_stats(void)
{
memset(&ebb_state.stats, 0, sizeof(ebb_state.stats));
}
void dump_summary_ebb_state(void)
{
printf("ebb_state:\n" \
" ebb_count = %d\n" \
" spurious = %d\n" \
" negative = %d\n" \
" no_overflow = %d\n" \
" pmc[1] count = 0x%llx\n" \
" pmc[2] count = 0x%llx\n" \
" pmc[3] count = 0x%llx\n" \
" pmc[4] count = 0x%llx\n" \
" pmc[5] count = 0x%llx\n" \
" pmc[6] count = 0x%llx\n",
ebb_state.stats.ebb_count, ebb_state.stats.spurious,
ebb_state.stats.negative, ebb_state.stats.no_overflow,
ebb_state.stats.pmc_count[0], ebb_state.stats.pmc_count[1],
ebb_state.stats.pmc_count[2], ebb_state.stats.pmc_count[3],
ebb_state.stats.pmc_count[4], ebb_state.stats.pmc_count[5]);
}
static char *decode_mmcr0(u32 value)
{
static char buf[16];
buf[0] = '\0';
if (value & (1 << 31))
strcat(buf, "FC ");
if (value & (1 << 26))
strcat(buf, "PMAE ");
if (value & (1 << 7))
strcat(buf, "PMAO ");
return buf;
}
static char *decode_bescr(u64 value)
{
static char buf[16];
buf[0] = '\0';
if (value & (1ull << 63))
strcat(buf, "GE ");
if (value & (1ull << 32))
strcat(buf, "PMAE ");
if (value & 1)
strcat(buf, "PMAO ");
return buf;
}
void dump_ebb_hw_state(void)
{
u64 bescr;
u32 mmcr0;
mmcr0 = mfspr(SPRN_MMCR0);
bescr = mfspr(SPRN_BESCR);
printf("HW state:\n" \
"MMCR0 0x%016x %s\n" \
"EBBHR 0x%016lx\n" \
"BESCR 0x%016llx %s\n" \
"PMC1 0x%016lx\n" \
"PMC2 0x%016lx\n" \
"PMC3 0x%016lx\n" \
"PMC4 0x%016lx\n" \
"PMC5 0x%016lx\n" \
"PMC6 0x%016lx\n" \
"SIAR 0x%016lx\n",
mmcr0, decode_mmcr0(mmcr0), mfspr(SPRN_EBBHR), bescr,
decode_bescr(bescr), mfspr(SPRN_PMC1), mfspr(SPRN_PMC2),
mfspr(SPRN_PMC3), mfspr(SPRN_PMC4), mfspr(SPRN_PMC5),
mfspr(SPRN_PMC6), mfspr(SPRN_SIAR));
}
void dump_ebb_state(void)
{
dump_summary_ebb_state();
dump_ebb_hw_state();
trace_buffer_print(ebb_state.trace);
}
int count_pmc(int pmc, uint32_t sample_period)
{
uint32_t start_value;
u64 val;
/* 0) Read PMC */
start_value = pmc_sample_period(sample_period);
val = read_pmc(pmc);
if (val < start_value)
ebb_state.stats.negative++;
else
ebb_state.stats.pmc_count[PMC_INDEX(pmc)] += val - start_value;
trace_log_reg(ebb_state.trace, SPRN_PMC1 + pmc - 1, val);
/* 1) Reset PMC */
write_pmc(pmc, start_value);
/* Report if we overflowed */
return val >= COUNTER_OVERFLOW;
}
int ebb_event_enable(struct event *e)
{
int rc;
/* Ensure any SPR writes are ordered vs us */
mb();
rc = ioctl(e->fd, PERF_EVENT_IOC_ENABLE);
if (rc)
ret
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