selftests/powerpc: Add tests of PMU EBBs

The Power8 Performance Monitor Unit (PMU) has a new feature called Event
Based Branches (EBB). This commit adds tests of the kernel API for using
EBBs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Michael Ellerman 2014-06-10 22:23:10 +10:00 committed by Benjamin Herrenschmidt
parent 33b4819f3b
commit 3752e453f6
34 changed files with 3913 additions and 4 deletions

View File

@ -4,7 +4,7 @@ noarg:
PROGS := count_instructions
EXTRA_SOURCES := ../harness.c event.c
all: $(PROGS)
all: $(PROGS) sub_all
$(PROGS): $(EXTRA_SOURCES)
@ -12,12 +12,30 @@ $(PROGS): $(EXTRA_SOURCES)
count_instructions: loop.S count_instructions.c $(EXTRA_SOURCES)
$(CC) $(CFLAGS) -m64 -o $@ $^
run_tests: all
run_tests: all sub_run_tests
@-for PROG in $(PROGS); do \
./$$PROG; \
done;
clean:
clean: sub_clean
rm -f $(PROGS) loop.o
.PHONY: all run_tests clean
SUB_TARGETS = ebb
sub_all:
@for TARGET in $(SUB_TARGETS); do \
$(MAKE) -C $$TARGET all; \
done;
sub_run_tests: all
@for TARGET in $(SUB_TARGETS); do \
$(MAKE) -C $$TARGET run_tests; \
done;
sub_clean:
@for TARGET in $(SUB_TARGETS); do \
$(MAKE) -C $$TARGET clean; \
done;
.PHONY: all run_tests clean sub_all sub_run_tests sub_clean

View File

@ -0,0 +1,32 @@
noarg:
$(MAKE) -C ../../
# The EBB handler is 64-bit code and everything links against it
CFLAGS += -m64
PROGS := reg_access_test event_attributes_test cycles_test \
cycles_with_freeze_test pmc56_overflow_test \
ebb_vs_cpu_event_test cpu_event_vs_ebb_test \
cpu_event_pinned_vs_ebb_test task_event_vs_ebb_test \
task_event_pinned_vs_ebb_test multi_ebb_procs_test \
multi_counter_test pmae_handling_test \
close_clears_pmcc_test instruction_count_test \
fork_cleanup_test ebb_on_child_test \
ebb_on_willing_child_test back_to_back_ebbs_test \
lost_exception_test no_handler_test
all: $(PROGS)
$(PROGS): ../../harness.c ../event.c ../lib.c ebb.c ebb_handler.S trace.c
instruction_count_test: ../loop.S
lost_exception_test: ../lib.c
run_tests: all
@-for PROG in $(PROGS); do \
./$$PROG; \
done;
clean:
rm -f $(PROGS)

View File

@ -0,0 +1,106 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include "ebb.h"
#define NUMBER_OF_EBBS 50
/*
* Test that if we overflow the counter while in the EBB handler, we take
* another EBB on exiting from the handler.
*
* We do this by counting with a stupidly low sample period, causing us to
* overflow the PMU while we're still in the EBB handler, leading to another
* EBB.
*
* We get out of what would otherwise be an infinite loop by leaving the
* counter frozen once we've taken enough EBBs.
*/
static void ebb_callee(void)
{
uint64_t siar, 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);
/* Resets the PMC */
count_pmc(1, sample_period);
out:
if (ebb_state.stats.ebb_count == NUMBER_OF_EBBS)
/* Reset but leave counters frozen */
reset_ebb_with_clear_mask(MMCR0_PMAO);
else
/* Unfreezes */
reset_ebb();
/* Do some stuff to chew some cycles and pop the counter */
siar = mfspr(SPRN_SIAR);
trace_log_reg(ebb_state.trace, SPRN_SIAR, siar);
val = mfspr(SPRN_PMC1);
trace_log_reg(ebb_state.trace, SPRN_PMC1, val);
val = mfspr(SPRN_MMCR0);
trace_log_reg(ebb_state.trace, SPRN_MMCR0, val);
}
int back_to_back_ebbs(void)
{
struct event event;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
setup_ebb_handler(ebb_callee);
FAIL_IF(ebb_event_enable(&event));
sample_period = 5;
ebb_freeze_pmcs();
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
ebb_global_enable();
ebb_unfreeze_pmcs();
while (ebb_state.stats.ebb_count < NUMBER_OF_EBBS)
FAIL_IF(core_busy_loop());
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count != NUMBER_OF_EBBS);
return 0;
}
int main(void)
{
return test_harness(back_to_back_ebbs, "back_to_back_ebbs");
}

View File

@ -0,0 +1,59 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>
#include <signal.h>
#include "ebb.h"
/*
* Test that closing the EBB event clears MMCR0_PMCC, preventing further access
* by userspace to the PMU hardware.
*/
int close_clears_pmcc(void)
{
struct event event;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
FAIL_IF(event_open(&event));
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
while (ebb_state.stats.ebb_count < 1)
FAIL_IF(core_busy_loop());
ebb_global_disable();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
/* The real test is here, do we take a SIGILL when writing PMU regs now
* that we have closed the event. We expect that we will. */
FAIL_IF(catch_sigill(write_pmc1));
/* We should still be able to read EBB regs though */
mfspr(SPRN_EBBHR);
mfspr(SPRN_EBBRR);
mfspr(SPRN_BESCR);
return 0;
}
int main(void)
{
return test_harness(close_clears_pmcc, "close_clears_pmcc");
}

View File

@ -0,0 +1,93 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests a pinned cpu event vs an EBB - in that order. The pinned cpu event
* should remain and the EBB event should fail to enable.
*/
static int setup_cpu_event(struct event *event, int cpu)
{
event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
event->attr.pinned = 1;
event->attr.exclude_kernel = 1;
event->attr.exclude_hv = 1;
event->attr.exclude_idle = 1;
SKIP_IF(require_paranoia_below(1));
FAIL_IF(event_open_with_cpu(event, cpu));
FAIL_IF(event_enable(event));
return 0;
}
int cpu_event_pinned_vs_ebb(void)
{
union pipe read_pipe, write_pipe;
struct event event;
int cpu, rc;
pid_t pid;
cpu = pick_online_cpu();
FAIL_IF(cpu < 0);
FAIL_IF(bind_to_cpu(cpu));
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(ebb_child(write_pipe, read_pipe));
}
/* We setup the cpu event first */
rc = setup_cpu_event(&event, cpu);
if (rc) {
kill_child_and_wait(pid);
return rc;
}
/* Signal the child to install its EBB event and wait */
if (sync_with_child(read_pipe, write_pipe))
/* If it fails, wait for it to exit */
goto wait;
/* Signal the child to run */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
wait:
/* We expect it to fail to read the event */
FAIL_IF(wait_for_child(pid) != 2);
FAIL_IF(event_disable(&event));
FAIL_IF(event_read(&event));
event_report(&event);
/* The cpu event should have run */
FAIL_IF(event.result.value == 0);
FAIL_IF(event.result.enabled != event.result.running);
return 0;
}
int main(void)
{
return test_harness(cpu_event_pinned_vs_ebb, "cpu_event_pinned_vs_ebb");
}

View File

@ -0,0 +1,89 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests a cpu event vs an EBB - in that order. The EBB should force the cpu
* event off the PMU.
*/
static int setup_cpu_event(struct event *event, int cpu)
{
event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
event->attr.exclude_kernel = 1;
event->attr.exclude_hv = 1;
event->attr.exclude_idle = 1;
SKIP_IF(require_paranoia_below(1));
FAIL_IF(event_open_with_cpu(event, cpu));
FAIL_IF(event_enable(event));
return 0;
}
int cpu_event_vs_ebb(void)
{
union pipe read_pipe, write_pipe;
struct event event;
int cpu, rc;
pid_t pid;
cpu = pick_online_cpu();
FAIL_IF(cpu < 0);
FAIL_IF(bind_to_cpu(cpu));
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(ebb_child(write_pipe, read_pipe));
}
/* We setup the cpu event first */
rc = setup_cpu_event(&event, cpu);
if (rc) {
kill_child_and_wait(pid);
return rc;
}
/* Signal the child to install its EBB event and wait */
if (sync_with_child(read_pipe, write_pipe))
/* If it fails, wait for it to exit */
goto wait;
/* Signal the child to run */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
wait:
/* We expect the child to succeed */
FAIL_IF(wait_for_child(pid));
FAIL_IF(event_disable(&event));
FAIL_IF(event_read(&event));
event_report(&event);
/* The cpu event may have run */
return 0;
}
int main(void)
{
return test_harness(cpu_event_vs_ebb, "cpu_event_vs_ebb");
}

View File

@ -0,0 +1,58 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include "ebb.h"
/*
* Basic test that counts user cycles and takes EBBs.
*/
int cycles(void)
{
struct event event;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
while (ebb_state.stats.ebb_count < 10) {
FAIL_IF(core_busy_loop());
FAIL_IF(ebb_check_mmcr0());
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
FAIL_IF(!ebb_check_count(1, sample_period, 100));
return 0;
}
int main(void)
{
return test_harness(cycles, "cycles");
}

View File

@ -0,0 +1,117 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include "ebb.h"
/*
* Test of counting cycles while using MMCR0_FC (freeze counters) to only count
* parts of the code. This is complicated by the fact that FC is set by the
* hardware when the event overflows. We may take the EBB after we have set FC,
* so we have to be careful about whether we clear FC at the end of the EBB
* handler or not.
*/
static bool counters_frozen = false;
static int ebbs_while_frozen = 0;
static void ebb_callee(void)
{
uint64_t mask, val;
mask = MMCR0_PMAO | MMCR0_FC;
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);
if (counters_frozen) {
trace_log_string(ebb_state.trace, "frozen");
ebbs_while_frozen++;
mask &= ~MMCR0_FC;
}
count_pmc(1, sample_period);
out:
reset_ebb_with_clear_mask(mask);
}
int cycles_with_freeze(void)
{
struct event event;
uint64_t val;
bool fc_cleared;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
setup_ebb_handler(ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
fc_cleared = false;
/* Make sure we loop until we take at least one EBB */
while ((ebb_state.stats.ebb_count < 20 && !fc_cleared) ||
ebb_state.stats.ebb_count < 1)
{
counters_frozen = false;
mb();
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_FC);
FAIL_IF(core_busy_loop());
counters_frozen = true;
mb();
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) | MMCR0_FC);
val = mfspr(SPRN_MMCR0);
if (! (val & MMCR0_FC)) {
printf("Outside of loop, FC NOT set MMCR0 0x%lx\n", val);
fc_cleared = true;
}
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
printf("EBBs while frozen %d\n", ebbs_while_frozen);
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
FAIL_IF(fc_cleared);
return 0;
}
int main(void)
{
return test_harness(cycles_with_freeze, "cycles_with_freeze");
}

View File

@ -0,0 +1,727 @@
/*
* 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)
return rc;
rc = event_read(e);
/* Ditto */
mb();
return rc;
}
void ebb_freeze_pmcs(void)
{
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) | MMCR0_FC);
mb();
}
void ebb_unfreeze_pmcs(void)
{
/* Unfreeze counters */
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_FC);
mb();
}
void ebb_global_enable(void)
{
/* Enable EBBs globally and PMU EBBs */
mtspr(SPRN_BESCR, 0x8000000100000000ull);
mb();
}
void ebb_global_disable(void)
{
/* Disable EBBs & freeze counters, events are still scheduled */
mtspr(SPRN_BESCRR, BESCR_PME);
mb();
}
void event_ebb_init(struct event *e)
{
e->attr.config |= (1ull << 63);
}
void event_bhrb_init(struct event *e, unsigned ifm)
{
e->attr.config |= (1ull << 62) | ((u64)ifm << 60);
}
void event_leader_ebb_init(struct event *e)
{
event_ebb_init(e);
e->attr.exclusive = 1;
e->attr.pinned = 1;
}
int core_busy_loop(void)
{
int rc;
asm volatile (
"li 3, 0x3030\n"
"std 3, -96(1)\n"
"li 4, 0x4040\n"
"std 4, -104(1)\n"
"li 5, 0x5050\n"
"std 5, -112(1)\n"
"li 6, 0x6060\n"
"std 6, -120(1)\n"
"li 7, 0x7070\n"
"std 7, -128(1)\n"
"li 8, 0x0808\n"
"std 8, -136(1)\n"
"li 9, 0x0909\n"
"std 9, -144(1)\n"
"li 10, 0x1010\n"
"std 10, -152(1)\n"
"li 11, 0x1111\n"
"std 11, -160(1)\n"
"li 14, 0x1414\n"
"std 14, -168(1)\n"
"li 15, 0x1515\n"
"std 15, -176(1)\n"
"li 16, 0x1616\n"
"std 16, -184(1)\n"
"li 17, 0x1717\n"
"std 17, -192(1)\n"
"li 18, 0x1818\n"
"std 18, -200(1)\n"
"li 19, 0x1919\n"
"std 19, -208(1)\n"
"li 20, 0x2020\n"
"std 20, -216(1)\n"
"li 21, 0x2121\n"
"std 21, -224(1)\n"
"li 22, 0x2222\n"
"std 22, -232(1)\n"
"li 23, 0x2323\n"
"std 23, -240(1)\n"
"li 24, 0x2424\n"
"std 24, -248(1)\n"
"li 25, 0x2525\n"
"std 25, -256(1)\n"
"li 26, 0x2626\n"
"std 26, -264(1)\n"
"li 27, 0x2727\n"
"std 27, -272(1)\n"
"li 28, 0x2828\n"
"std 28, -280(1)\n"
"li 29, 0x2929\n"
"std 29, -288(1)\n"
"li 30, 0x3030\n"
"li 31, 0x3131\n"
"li 3, 0\n"
"0: "
"addi 3, 3, 1\n"
"cmpwi 3, 100\n"
"blt 0b\n"
/* Return 1 (fail) unless we get through all the checks */
"li 0, 1\n"
/* Check none of our registers have been corrupted */
"cmpwi 4, 0x4040\n"
"bne 1f\n"
"cmpwi 5, 0x5050\n"
"bne 1f\n"
"cmpwi 6, 0x6060\n"
"bne 1f\n"
"cmpwi 7, 0x7070\n"
"bne 1f\n"
"cmpwi 8, 0x0808\n"
"bne 1f\n"
"cmpwi 9, 0x0909\n"
"bne 1f\n"
"cmpwi 10, 0x1010\n"
"bne 1f\n"
"cmpwi 11, 0x1111\n"
"bne 1f\n"
"cmpwi 14, 0x1414\n"
"bne 1f\n"
"cmpwi 15, 0x1515\n"
"bne 1f\n"
"cmpwi 16, 0x1616\n"
"bne 1f\n"
"cmpwi 17, 0x1717\n"
"bne 1f\n"
"cmpwi 18, 0x1818\n"
"bne 1f\n"
"cmpwi 19, 0x1919\n"
"bne 1f\n"
"cmpwi 20, 0x2020\n"
"bne 1f\n"
"cmpwi 21, 0x2121\n"
"bne 1f\n"
"cmpwi 22, 0x2222\n"
"bne 1f\n"
"cmpwi 23, 0x2323\n"
"bne 1f\n"
"cmpwi 24, 0x2424\n"
"bne 1f\n"
"cmpwi 25, 0x2525\n"
"bne 1f\n"
"cmpwi 26, 0x2626\n"
"bne 1f\n"
"cmpwi 27, 0x2727\n"
"bne 1f\n"
"cmpwi 28, 0x2828\n"
"bne 1f\n"
"cmpwi 29, 0x2929\n"
"bne 1f\n"
"cmpwi 30, 0x3030\n"
"bne 1f\n"
"cmpwi 31, 0x3131\n"
"bne 1f\n"
/* Load junk into all our registers before we reload them from the stack. */
"li 3, 0xde\n"
"li 4, 0xad\n"
"li 5, 0xbe\n"
"li 6, 0xef\n"
"li 7, 0xde\n"
"li 8, 0xad\n"
"li 9, 0xbe\n"
"li 10, 0xef\n"
"li 11, 0xde\n"
"li 14, 0xad\n"
"li 15, 0xbe\n"
"li 16, 0xef\n"
"li 17, 0xde\n"
"li 18, 0xad\n"
"li 19, 0xbe\n"
"li 20, 0xef\n"
"li 21, 0xde\n"
"li 22, 0xad\n"
"li 23, 0xbe\n"
"li 24, 0xef\n"
"li 25, 0xde\n"
"li 26, 0xad\n"
"li 27, 0xbe\n"
"li 28, 0xef\n"
"li 29, 0xdd\n"
"ld 3, -96(1)\n"
"cmpwi 3, 0x3030\n"
"bne 1f\n"
"ld 4, -104(1)\n"
"cmpwi 4, 0x4040\n"
"bne 1f\n"
"ld 5, -112(1)\n"
"cmpwi 5, 0x5050\n"
"bne 1f\n"
"ld 6, -120(1)\n"
"cmpwi 6, 0x6060\n"
"bne 1f\n"
"ld 7, -128(1)\n"
"cmpwi 7, 0x7070\n"
"bne 1f\n"
"ld 8, -136(1)\n"
"cmpwi 8, 0x0808\n"
"bne 1f\n"
"ld 9, -144(1)\n"
"cmpwi 9, 0x0909\n"
"bne 1f\n"
"ld 10, -152(1)\n"
"cmpwi 10, 0x1010\n"
"bne 1f\n"
"ld 11, -160(1)\n"
"cmpwi 11, 0x1111\n"
"bne 1f\n"
"ld 14, -168(1)\n"
"cmpwi 14, 0x1414\n"
"bne 1f\n"
"ld 15, -176(1)\n"
"cmpwi 15, 0x1515\n"
"bne 1f\n"
"ld 16, -184(1)\n"
"cmpwi 16, 0x1616\n"
"bne 1f\n"
"ld 17, -192(1)\n"
"cmpwi 17, 0x1717\n"
"bne 1f\n"
"ld 18, -200(1)\n"
"cmpwi 18, 0x1818\n"
"bne 1f\n"
"ld 19, -208(1)\n"
"cmpwi 19, 0x1919\n"
"bne 1f\n"
"ld 20, -216(1)\n"
"cmpwi 20, 0x2020\n"
"bne 1f\n"
"ld 21, -224(1)\n"
"cmpwi 21, 0x2121\n"
"bne 1f\n"
"ld 22, -232(1)\n"
"cmpwi 22, 0x2222\n"
"bne 1f\n"
"ld 23, -240(1)\n"
"cmpwi 23, 0x2323\n"
"bne 1f\n"
"ld 24, -248(1)\n"
"cmpwi 24, 0x2424\n"
"bne 1f\n"
"ld 25, -256(1)\n"
"cmpwi 25, 0x2525\n"
"bne 1f\n"
"ld 26, -264(1)\n"
"cmpwi 26, 0x2626\n"
"bne 1f\n"
"ld 27, -272(1)\n"
"cmpwi 27, 0x2727\n"
"bne 1f\n"
"ld 28, -280(1)\n"
"cmpwi 28, 0x2828\n"
"bne 1f\n"
"ld 29, -288(1)\n"
"cmpwi 29, 0x2929\n"
"bne 1f\n"
/* Load 0 (success) to return */
"li 0, 0\n"
"1: mr %0, 0\n"
: "=r" (rc)
: /* no inputs */
: "3", "4", "5", "6", "7", "8", "9", "10", "11", "14",
"15", "16", "17", "18", "19", "20", "21", "22", "23",
"24", "25", "26", "27", "28", "29", "30", "31",
"memory"
);
return rc;
}
int core_busy_loop_with_freeze(void)
{
int rc;
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_FC);
rc = core_busy_loop();
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) | MMCR0_FC);
return rc;
}
int ebb_child(union pipe read_pipe, union pipe write_pipe)
{
struct event event;
uint64_t val;
FAIL_IF(wait_for_parent(read_pipe));
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(event_enable(&event));
if (event_read(&event)) {
/*
* Some tests expect to fail here, so don't report an error on
* this line, and return a distinguisable error code. Tell the
* parent an error happened.
*/
notify_parent_of_error(write_pipe);
return 2;
}
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
FAIL_IF(notify_parent(write_pipe));
FAIL_IF(wait_for_parent(read_pipe));
FAIL_IF(notify_parent(write_pipe));
while (ebb_state.stats.ebb_count < 20) {
FAIL_IF(core_busy_loop());
/* To try and hit SIGILL case */
val = mfspr(SPRN_MMCRA);
val |= mfspr(SPRN_MMCR2);
val |= mfspr(SPRN_MMCR0);
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
return 0;
}
static jmp_buf setjmp_env;
static void sigill_handler(int signal)
{
printf("Took sigill\n");
longjmp(setjmp_env, 1);
}
static struct sigaction sigill_action = {
.sa_handler = sigill_handler,
};
int catch_sigill(void (*func)(void))
{
if (sigaction(SIGILL, &sigill_action, NULL)) {
perror("sigaction");
return 1;
}
if (setjmp(setjmp_env) == 0) {
func();
return 1;
}
return 0;
}
void write_pmc1(void)
{
mtspr(SPRN_PMC1, 0);
}
void write_pmc(int pmc, u64 value)
{
switch (pmc) {
case 1: mtspr(SPRN_PMC1, value); break;
case 2: mtspr(SPRN_PMC2, value); break;
case 3: mtspr(SPRN_PMC3, value); break;
case 4: mtspr(SPRN_PMC4, value); break;
case 5: mtspr(SPRN_PMC5, value); break;
case 6: mtspr(SPRN_PMC6, value); break;
}
}
u64 read_pmc(int pmc)
{
switch (pmc) {
case 1: return mfspr(SPRN_PMC1);
case 2: return mfspr(SPRN_PMC2);
case 3: return mfspr(SPRN_PMC3);
case 4: return mfspr(SPRN_PMC4);
case 5: return mfspr(SPRN_PMC5);
case 6: return mfspr(SPRN_PMC6);
}
return 0;
}
static void term_handler(int signal)
{
dump_summary_ebb_state();
dump_ebb_hw_state();
abort();
}
struct sigaction term_action = {
.sa_handler = term_handler,
};
static void __attribute__((constructor)) ebb_init(void)
{
clear_ebb_stats();
if (sigaction(SIGTERM, &term_action, NULL))
perror("sigaction");
ebb_state.trace = trace_buffer_allocate(1 * 1024 * 1024);
}

View File

@ -0,0 +1,78 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#ifndef _SELFTESTS_POWERPC_PMU_EBB_EBB_H
#define _SELFTESTS_POWERPC_PMU_EBB_EBB_H
#include "../event.h"
#include "../lib.h"
#include "trace.h"
#include "reg.h"
#define PMC_INDEX(pmc) ((pmc)-1)
#define NUM_PMC_VALUES 128
struct ebb_state
{
struct {
u64 pmc_count[6];
volatile int ebb_count;
int spurious;
int negative;
int no_overflow;
} stats;
bool pmc_enable[6];
struct trace_buffer *trace;
};
extern struct ebb_state ebb_state;
#define COUNTER_OVERFLOW 0x80000000ull
static inline uint32_t pmc_sample_period(uint32_t value)
{
return COUNTER_OVERFLOW - value;
}
static inline void ebb_enable_pmc_counting(int pmc)
{
ebb_state.pmc_enable[PMC_INDEX(pmc)] = true;
}
bool ebb_check_count(int pmc, u64 sample_period, int fudge);
void event_leader_ebb_init(struct event *e);
void event_ebb_init(struct event *e);
void event_bhrb_init(struct event *e, unsigned ifm);
void setup_ebb_handler(void (*callee)(void));
void standard_ebb_callee(void);
int ebb_event_enable(struct event *e);
void ebb_global_enable(void);
void ebb_global_disable(void);
void ebb_freeze_pmcs(void);
void ebb_unfreeze_pmcs(void);
void event_ebb_init(struct event *e);
void event_leader_ebb_init(struct event *e);
int count_pmc(int pmc, uint32_t sample_period);
void dump_ebb_state(void);
void dump_summary_ebb_state(void);
void dump_ebb_hw_state(void);
void clear_ebb_stats(void);
void write_pmc(int pmc, u64 value);
u64 read_pmc(int pmc);
void reset_ebb_with_clear_mask(unsigned long mmcr0_clear_mask);
void reset_ebb(void);
int ebb_check_mmcr0(void);
extern u64 sample_period;
int core_busy_loop(void);
int core_busy_loop_with_freeze(void);
int ebb_child(union pipe read_pipe, union pipe write_pipe);
int catch_sigill(void (*func)(void));
void write_pmc1(void);
#endif /* _SELFTESTS_POWERPC_PMU_EBB_EBB_H */

View File

@ -0,0 +1,365 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <ppc-asm.h>
#include "reg.h"
/* ppc-asm.h defines most of the reg aliases, but not r1/r2. */
#define r1 1
#define r2 2
#define RFEBB .long 0x4c000924
/* Stack layout:
*
* ^
* User stack |
* Back chain ------+ <- r1 <-------+
* ... |
* Red zone / ABI Gap |
* ... |
* vr63 <+ |
* vr0 | |
* VSCR | |
* FSCR | |
* r31 | Save area |
* r0 | |
* XER | |
* CTR | |
* LR | |
* CCR <+ |
* ... <+ |
* LR | Caller frame |
* CCR | |
* Back chain <+ <- updated r1 --------+
*
*/
#if defined(_CALL_ELF) && _CALL_ELF == 2
#define ABIGAP 512
#else
#define ABIGAP 288
#endif
#define NR_GPR 32
#define NR_SPR 6
#define NR_VSR 64
#define SAVE_AREA ((NR_GPR + NR_SPR) * 8 + (NR_VSR * 16))
#define CALLER_FRAME 112
#define STACK_FRAME (ABIGAP + SAVE_AREA + CALLER_FRAME)
#define CCR_SAVE (CALLER_FRAME)
#define LR_SAVE (CCR_SAVE + 8)
#define CTR_SAVE (LR_SAVE + 8)
#define XER_SAVE (CTR_SAVE + 8)
#define GPR_SAVE(n) (XER_SAVE + 8 + (8 * n))
#define FSCR_SAVE (GPR_SAVE(31) + 8)
#define VSCR_SAVE (FSCR_SAVE + 8)
#define VSR_SAVE(n) (VSCR_SAVE + 8 + (16 * n))
#define SAVE_GPR(n) std n,GPR_SAVE(n)(r1)
#define REST_GPR(n) ld n,GPR_SAVE(n)(r1)
#define TRASH_GPR(n) lis n,0xaaaa
#define SAVE_VSR(n, b) li b, VSR_SAVE(n); stxvd2x n,b,r1
#define LOAD_VSR(n, b) li b, VSR_SAVE(n); lxvd2x n,b,r1
#define LOAD_REG_IMMEDIATE(reg,expr) \
lis reg,(expr)@highest; \
ori reg,reg,(expr)@higher; \
rldicr reg,reg,32,31; \
oris reg,reg,(expr)@h; \
ori reg,reg,(expr)@l;
#if defined(_CALL_ELF) && _CALL_ELF == 2
#define ENTRY_POINT(name) \
.type FUNC_NAME(name),@function; \
.globl FUNC_NAME(name); \
FUNC_NAME(name):
#define RESTORE_TOC(name) \
/* Restore our TOC pointer using our entry point */ \
LOAD_REG_IMMEDIATE(r12, name) \
0: addis r2,r12,(.TOC.-0b)@ha; \
addi r2,r2,(.TOC.-0b)@l;
#else
#define ENTRY_POINT(name) FUNC_START(name)
#define RESTORE_TOC(name) \
/* Restore our TOC pointer via our opd entry */ \
LOAD_REG_IMMEDIATE(r2, name) \
ld r2,8(r2);
#endif
.text
ENTRY_POINT(ebb_handler)
stdu r1,-STACK_FRAME(r1)
SAVE_GPR(0)
mflr r0
std r0,LR_SAVE(r1)
mfcr r0
std r0,CCR_SAVE(r1)
mfctr r0
std r0,CTR_SAVE(r1)
mfxer r0
std r0,XER_SAVE(r1)
SAVE_GPR(2)
SAVE_GPR(3)
SAVE_GPR(4)
SAVE_GPR(5)
SAVE_GPR(6)
SAVE_GPR(7)
SAVE_GPR(8)
SAVE_GPR(9)
SAVE_GPR(10)
SAVE_GPR(11)
SAVE_GPR(12)
SAVE_GPR(13)
SAVE_GPR(14)
SAVE_GPR(15)
SAVE_GPR(16)
SAVE_GPR(17)
SAVE_GPR(18)
SAVE_GPR(19)
SAVE_GPR(20)
SAVE_GPR(21)
SAVE_GPR(22)
SAVE_GPR(23)
SAVE_GPR(24)
SAVE_GPR(25)
SAVE_GPR(26)
SAVE_GPR(27)
SAVE_GPR(28)
SAVE_GPR(29)
SAVE_GPR(30)
SAVE_GPR(31)
SAVE_VSR(0, r3)
mffs f0
stfd f0, FSCR_SAVE(r1)
mfvscr f0
stfd f0, VSCR_SAVE(r1)
SAVE_VSR(1, r3)
SAVE_VSR(2, r3)
SAVE_VSR(3, r3)
SAVE_VSR(4, r3)
SAVE_VSR(5, r3)
SAVE_VSR(6, r3)
SAVE_VSR(7, r3)
SAVE_VSR(8, r3)
SAVE_VSR(9, r3)
SAVE_VSR(10, r3)
SAVE_VSR(11, r3)
SAVE_VSR(12, r3)
SAVE_VSR(13, r3)
SAVE_VSR(14, r3)
SAVE_VSR(15, r3)
SAVE_VSR(16, r3)
SAVE_VSR(17, r3)
SAVE_VSR(18, r3)
SAVE_VSR(19, r3)
SAVE_VSR(20, r3)
SAVE_VSR(21, r3)
SAVE_VSR(22, r3)
SAVE_VSR(23, r3)
SAVE_VSR(24, r3)
SAVE_VSR(25, r3)
SAVE_VSR(26, r3)
SAVE_VSR(27, r3)
SAVE_VSR(28, r3)
SAVE_VSR(29, r3)
SAVE_VSR(30, r3)
SAVE_VSR(31, r3)
SAVE_VSR(32, r3)
SAVE_VSR(33, r3)
SAVE_VSR(34, r3)
SAVE_VSR(35, r3)
SAVE_VSR(36, r3)
SAVE_VSR(37, r3)
SAVE_VSR(38, r3)
SAVE_VSR(39, r3)
SAVE_VSR(40, r3)
SAVE_VSR(41, r3)
SAVE_VSR(42, r3)
SAVE_VSR(43, r3)
SAVE_VSR(44, r3)
SAVE_VSR(45, r3)
SAVE_VSR(46, r3)
SAVE_VSR(47, r3)
SAVE_VSR(48, r3)
SAVE_VSR(49, r3)
SAVE_VSR(50, r3)
SAVE_VSR(51, r3)
SAVE_VSR(52, r3)
SAVE_VSR(53, r3)
SAVE_VSR(54, r3)
SAVE_VSR(55, r3)
SAVE_VSR(56, r3)
SAVE_VSR(57, r3)
SAVE_VSR(58, r3)
SAVE_VSR(59, r3)
SAVE_VSR(60, r3)
SAVE_VSR(61, r3)
SAVE_VSR(62, r3)
SAVE_VSR(63, r3)
TRASH_GPR(2)
TRASH_GPR(3)
TRASH_GPR(4)
TRASH_GPR(5)
TRASH_GPR(6)
TRASH_GPR(7)
TRASH_GPR(8)
TRASH_GPR(9)
TRASH_GPR(10)
TRASH_GPR(11)
TRASH_GPR(12)
TRASH_GPR(14)
TRASH_GPR(15)
TRASH_GPR(16)
TRASH_GPR(17)
TRASH_GPR(18)
TRASH_GPR(19)
TRASH_GPR(20)
TRASH_GPR(21)
TRASH_GPR(22)
TRASH_GPR(23)
TRASH_GPR(24)
TRASH_GPR(25)
TRASH_GPR(26)
TRASH_GPR(27)
TRASH_GPR(28)
TRASH_GPR(29)
TRASH_GPR(30)
TRASH_GPR(31)
RESTORE_TOC(ebb_handler)
/*
* r13 is our TLS pointer. We leave whatever value was in there when the
* EBB fired. That seems to be OK because once set the TLS pointer is not
* changed - but presumably that could change in future.
*/
bl ebb_hook
nop
/* r2 may be changed here but we don't care */
lfd f0, FSCR_SAVE(r1)
mtfsf 0xff,f0
lfd f0, VSCR_SAVE(r1)
mtvscr f0
LOAD_VSR(0, r3)
LOAD_VSR(1, r3)
LOAD_VSR(2, r3)
LOAD_VSR(3, r3)
LOAD_VSR(4, r3)
LOAD_VSR(5, r3)
LOAD_VSR(6, r3)
LOAD_VSR(7, r3)
LOAD_VSR(8, r3)
LOAD_VSR(9, r3)
LOAD_VSR(10, r3)
LOAD_VSR(11, r3)
LOAD_VSR(12, r3)
LOAD_VSR(13, r3)
LOAD_VSR(14, r3)
LOAD_VSR(15, r3)
LOAD_VSR(16, r3)
LOAD_VSR(17, r3)
LOAD_VSR(18, r3)
LOAD_VSR(19, r3)
LOAD_VSR(20, r3)
LOAD_VSR(21, r3)
LOAD_VSR(22, r3)
LOAD_VSR(23, r3)
LOAD_VSR(24, r3)
LOAD_VSR(25, r3)
LOAD_VSR(26, r3)
LOAD_VSR(27, r3)
LOAD_VSR(28, r3)
LOAD_VSR(29, r3)
LOAD_VSR(30, r3)
LOAD_VSR(31, r3)
LOAD_VSR(32, r3)
LOAD_VSR(33, r3)
LOAD_VSR(34, r3)
LOAD_VSR(35, r3)
LOAD_VSR(36, r3)
LOAD_VSR(37, r3)
LOAD_VSR(38, r3)
LOAD_VSR(39, r3)
LOAD_VSR(40, r3)
LOAD_VSR(41, r3)
LOAD_VSR(42, r3)
LOAD_VSR(43, r3)
LOAD_VSR(44, r3)
LOAD_VSR(45, r3)
LOAD_VSR(46, r3)
LOAD_VSR(47, r3)
LOAD_VSR(48, r3)
LOAD_VSR(49, r3)
LOAD_VSR(50, r3)
LOAD_VSR(51, r3)
LOAD_VSR(52, r3)
LOAD_VSR(53, r3)
LOAD_VSR(54, r3)
LOAD_VSR(55, r3)
LOAD_VSR(56, r3)
LOAD_VSR(57, r3)
LOAD_VSR(58, r3)
LOAD_VSR(59, r3)
LOAD_VSR(60, r3)
LOAD_VSR(61, r3)
LOAD_VSR(62, r3)
LOAD_VSR(63, r3)
ld r0,XER_SAVE(r1)
mtxer r0
ld r0,CTR_SAVE(r1)
mtctr r0
ld r0,LR_SAVE(r1)
mtlr r0
ld r0,CCR_SAVE(r1)
mtcr r0
REST_GPR(0)
REST_GPR(2)
REST_GPR(3)
REST_GPR(4)
REST_GPR(5)
REST_GPR(6)
REST_GPR(7)
REST_GPR(8)
REST_GPR(9)
REST_GPR(10)
REST_GPR(11)
REST_GPR(12)
REST_GPR(13)
REST_GPR(14)
REST_GPR(15)
REST_GPR(16)
REST_GPR(17)
REST_GPR(18)
REST_GPR(19)
REST_GPR(20)
REST_GPR(21)
REST_GPR(22)
REST_GPR(23)
REST_GPR(24)
REST_GPR(25)
REST_GPR(26)
REST_GPR(27)
REST_GPR(28)
REST_GPR(29)
REST_GPR(30)
REST_GPR(31)
addi r1,r1,STACK_FRAME
RFEBB
FUNC_END(ebb_handler)

View File

@ -0,0 +1,86 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests we can setup an EBB on our child. Nothing interesting happens, because
* even though the event is enabled and running the child hasn't enabled the
* actual delivery of the EBBs.
*/
static int victim_child(union pipe read_pipe, union pipe write_pipe)
{
int i;
FAIL_IF(wait_for_parent(read_pipe));
FAIL_IF(notify_parent(write_pipe));
/* Parent creates EBB event */
FAIL_IF(wait_for_parent(read_pipe));
FAIL_IF(notify_parent(write_pipe));
/* Check the EBB is enabled by writing PMC1 */
write_pmc1();
/* EBB event is enabled here */
for (i = 0; i < 1000000; i++) ;
return 0;
}
int ebb_on_child(void)
{
union pipe read_pipe, write_pipe;
struct event event;
pid_t pid;
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(victim_child(write_pipe, read_pipe));
}
FAIL_IF(sync_with_child(read_pipe, write_pipe));
/* Child is running now */
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open_with_pid(&event, pid));
FAIL_IF(ebb_event_enable(&event));
FAIL_IF(sync_with_child(read_pipe, write_pipe));
/* Child should just exit happily */
FAIL_IF(wait_for_child(pid));
event_close(&event);
return 0;
}
int main(void)
{
return test_harness(ebb_on_child, "ebb_on_child");
}

View File

@ -0,0 +1,92 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests we can setup an EBB on our child. The child expects this and enables
* EBBs, which are then delivered to the child, even though the event is
* created by the parent.
*/
static int victim_child(union pipe read_pipe, union pipe write_pipe)
{
FAIL_IF(wait_for_parent(read_pipe));
/* Setup our EBB handler, before the EBB event is created */
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(notify_parent(write_pipe));
while (ebb_state.stats.ebb_count < 20) {
FAIL_IF(core_busy_loop());
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
FAIL_IF(ebb_state.stats.ebb_count == 0);
return 0;
}
/* Tests we can setup an EBB on our child - if it's expecting it */
int ebb_on_willing_child(void)
{
union pipe read_pipe, write_pipe;
struct event event;
pid_t pid;
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(victim_child(write_pipe, read_pipe));
}
/* Signal the child to setup its EBB handler */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
/* Child is running now */
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open_with_pid(&event, pid));
FAIL_IF(ebb_event_enable(&event));
/* Child show now take EBBs and then exit */
FAIL_IF(wait_for_child(pid));
event_close(&event);
return 0;
}
int main(void)
{
return test_harness(ebb_on_willing_child, "ebb_on_willing_child");
}

View File

@ -0,0 +1,86 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests an EBB vs a cpu event - in that order. The EBB should force the cpu
* event off the PMU.
*/
static int setup_cpu_event(struct event *event, int cpu)
{
event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
event->attr.exclude_kernel = 1;
event->attr.exclude_hv = 1;
event->attr.exclude_idle = 1;
SKIP_IF(require_paranoia_below(1));
FAIL_IF(event_open_with_cpu(event, cpu));
FAIL_IF(event_enable(event));
return 0;
}
int ebb_vs_cpu_event(void)
{
union pipe read_pipe, write_pipe;
struct event event;
int cpu, rc;
pid_t pid;
cpu = pick_online_cpu();
FAIL_IF(cpu < 0);
FAIL_IF(bind_to_cpu(cpu));
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(ebb_child(write_pipe, read_pipe));
}
/* Signal the child to install its EBB event and wait */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
/* Now try to install our CPU event */
rc = setup_cpu_event(&event, cpu);
if (rc) {
kill_child_and_wait(pid);
return rc;
}
/* Signal the child to run */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
/* .. and wait for it to complete */
FAIL_IF(wait_for_child(pid));
FAIL_IF(event_disable(&event));
FAIL_IF(event_read(&event));
event_report(&event);
/* The cpu event may have run, but we don't expect 100% */
FAIL_IF(event.result.enabled >= event.result.running);
return 0;
}
int main(void)
{
return test_harness(ebb_vs_cpu_event, "ebb_vs_cpu_event");
}

View File

@ -0,0 +1,131 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include "ebb.h"
/*
* Test various attributes of the EBB event are enforced.
*/
int event_attributes(void)
{
struct event event, leader;
event_init(&event, 0x1001e);
event_leader_ebb_init(&event);
/* Expected to succeed */
FAIL_IF(event_open(&event));
event_close(&event);
event_init(&event, 0x001e); /* CYCLES - no PMC specified */
event_leader_ebb_init(&event);
/* Expected to fail, no PMC specified */
FAIL_IF(event_open(&event) == 0);
event_init(&event, 0x2001e);
event_leader_ebb_init(&event);
event.attr.exclusive = 0;
/* Expected to fail, not exclusive */
FAIL_IF(event_open(&event) == 0);
event_init(&event, 0x3001e);
event_leader_ebb_init(&event);
event.attr.freq = 1;
/* Expected to fail, sets freq */
FAIL_IF(event_open(&event) == 0);
event_init(&event, 0x4001e);
event_leader_ebb_init(&event);
event.attr.sample_period = 1;
/* Expected to fail, sets sample_period */
FAIL_IF(event_open(&event) == 0);
event_init(&event, 0x1001e);
event_leader_ebb_init(&event);
event.attr.enable_on_exec = 1;
/* Expected to fail, sets enable_on_exec */
FAIL_IF(event_open(&event) == 0);
event_init(&event, 0x1001e);
event_leader_ebb_init(&event);
event.attr.inherit = 1;
/* Expected to fail, sets inherit */
FAIL_IF(event_open(&event) == 0);
event_init(&leader, 0x1001e);
event_leader_ebb_init(&leader);
FAIL_IF(event_open(&leader));
event_init(&event, 0x20002);
event_ebb_init(&event);
/* Expected to succeed */
FAIL_IF(event_open_with_group(&event, leader.fd));
event_close(&leader);
event_close(&event);
event_init(&leader, 0x1001e);
event_leader_ebb_init(&leader);
FAIL_IF(event_open(&leader));
event_init(&event, 0x20002);
/* Expected to fail, event doesn't request EBB, leader does */
FAIL_IF(event_open_with_group(&event, leader.fd) == 0);
event_close(&leader);
event_init(&leader, 0x1001e);
event_leader_ebb_init(&leader);
/* Clear the EBB flag */
leader.attr.config &= ~(1ull << 63);
FAIL_IF(event_open(&leader));
event_init(&event, 0x20002);
event_ebb_init(&event);
/* Expected to fail, leader doesn't request EBB */
FAIL_IF(event_open_with_group(&event, leader.fd) == 0);
event_close(&leader);
event_init(&leader, 0x1001e);
event_leader_ebb_init(&leader);
leader.attr.exclusive = 0;
/* Expected to fail, leader isn't exclusive */
FAIL_IF(event_open(&leader) == 0);
event_init(&leader, 0x1001e);
event_leader_ebb_init(&leader);
leader.attr.pinned = 0;
/* Expected to fail, leader isn't pinned */
FAIL_IF(event_open(&leader) == 0);
event_init(&event, 0x1001e);
event_leader_ebb_init(&event);
/* Expected to fail, not a task event */
SKIP_IF(require_paranoia_below(1));
FAIL_IF(event_open_with_cpu(&event, 0) == 0);
return 0;
}
int main(void)
{
return test_harness(event_attributes, "event_attributes");
}

View File

@ -0,0 +1,43 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <ppc-asm.h>
.text
FUNC_START(thirty_two_instruction_loop)
cmpwi r3,0
beqlr
addi r4,r3,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1
addi r4,r4,1 # 28 addi's
subi r3,r3,1
b FUNC_NAME(thirty_two_instruction_loop)
FUNC_END(thirty_two_instruction_loop)

View File

@ -0,0 +1,79 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <setjmp.h>
#include <signal.h>
#include "ebb.h"
/*
* Test that a fork clears the PMU state of the child. eg. BESCR/EBBHR/EBBRR
* are cleared, and MMCR0_PMCC is reset, preventing the child from accessing
* the PMU.
*/
static struct event event;
static int child(void)
{
/* Even though we have EBE=0 we can still see the EBB regs */
FAIL_IF(mfspr(SPRN_BESCR) != 0);
FAIL_IF(mfspr(SPRN_EBBHR) != 0);
FAIL_IF(mfspr(SPRN_EBBRR) != 0);
FAIL_IF(catch_sigill(write_pmc1));
/* We can still read from the event, though it is on our parent */
FAIL_IF(event_read(&event));
return 0;
}
/* Tests that fork clears EBB state */
int fork_cleanup(void)
{
pid_t pid;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
FAIL_IF(event_open(&event));
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_MMCR0, MMCR0_FC);
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
/* Don't need to actually take any EBBs */
pid = fork();
if (pid == 0)
exit(child());
/* Child does the actual testing */
FAIL_IF(wait_for_child(pid));
/* After fork */
event_close(&event);
return 0;
}
int main(void)
{
return test_harness(fork_cleanup, "fork_cleanup");
}

View File

@ -0,0 +1,164 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <sys/prctl.h>
#include "ebb.h"
/*
* Run a calibrated instruction loop and count instructions executed using
* EBBs. Make sure the counts look right.
*/
extern void thirty_two_instruction_loop(uint64_t loops);
static bool counters_frozen = true;
static int do_count_loop(struct event *event, uint64_t instructions,
uint64_t overhead, bool report)
{
int64_t difference, expected;
double percentage;
clear_ebb_stats();
counters_frozen = false;
mb();
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_FC);
thirty_two_instruction_loop(instructions >> 5);
counters_frozen = true;
mb();
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) | MMCR0_FC);
count_pmc(4, sample_period);
event->result.value = ebb_state.stats.pmc_count[4-1];
expected = instructions + overhead;
difference = event->result.value - expected;
percentage = (double)difference / event->result.value * 100;
if (report) {
printf("Looped for %lu instructions, overhead %lu\n", instructions, overhead);
printf("Expected %lu\n", expected);
printf("Actual %llu\n", event->result.value);
printf("Error %ld, %f%%\n", difference, percentage);
printf("Took %d EBBs\n", ebb_state.stats.ebb_count);
}
if (difference < 0)
difference = -difference;
/* Tolerate a difference of up to 0.0001 % */
difference *= 10000 * 100;
if (difference / event->result.value)
return -1;
return 0;
}
/* Count how many instructions it takes to do a null loop */
static uint64_t determine_overhead(struct event *event)
{
uint64_t current, overhead;
int i;
do_count_loop(event, 0, 0, false);
overhead = event->result.value;
for (i = 0; i < 100; i++) {
do_count_loop(event, 0, 0, false);
current = event->result.value;
if (current < overhead) {
printf("Replacing overhead %lu with %lu\n", overhead, current);
overhead = current;
}
}
return overhead;
}
static void pmc4_ebb_callee(void)
{
uint64_t val;
val = mfspr(SPRN_BESCR);
if (!(val & BESCR_PMEO)) {
ebb_state.stats.spurious++;
goto out;
}
ebb_state.stats.ebb_count++;
count_pmc(4, sample_period);
out:
if (counters_frozen)
reset_ebb_with_clear_mask(MMCR0_PMAO);
else
reset_ebb();
}
int instruction_count(void)
{
struct event event;
uint64_t overhead;
event_init_named(&event, 0x400FA, "PM_RUN_INST_CMPL");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
FAIL_IF(ebb_event_enable(&event));
sample_period = COUNTER_OVERFLOW;
setup_ebb_handler(pmc4_ebb_callee);
mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_FC);
ebb_global_enable();
overhead = determine_overhead(&event);
printf("Overhead of null loop: %lu instructions\n", overhead);
/* Run for 1M instructions */
FAIL_IF(do_count_loop(&event, 0x100000, overhead, true));
/* Run for 10M instructions */
FAIL_IF(do_count_loop(&event, 0xa00000, overhead, true));
/* Run for 100M instructions */
FAIL_IF(do_count_loop(&event, 0x6400000, overhead, true));
/* Run for 1G instructions */
FAIL_IF(do_count_loop(&event, 0x40000000, overhead, true));
/* Run for 16G instructions */
FAIL_IF(do_count_loop(&event, 0x400000000, overhead, true));
/* Run for 64G instructions */
FAIL_IF(do_count_loop(&event, 0x1000000000, overhead, true));
/* Run for 128G instructions */
FAIL_IF(do_count_loop(&event, 0x2000000000, overhead, true));
ebb_global_disable();
event_close(&event);
printf("Finished OK\n");
return 0;
}
int main(void)
{
return test_harness(instruction_count, "instruction_count");
}

View File

@ -0,0 +1,100 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <sched.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include "ebb.h"
/*
* Test that tries to trigger CPU_FTR_PMAO_BUG. Which is a hardware defect
* where an exception triggers but we context switch before it is delivered and
* lose the exception.
*/
static int test_body(void)
{
int i, orig_period, max_period;
struct event event;
/* We use PMC4 to make sure the kernel switches all counters correctly */
event_init_named(&event, 0x40002, "instructions");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
ebb_enable_pmc_counting(4);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
/*
* We want a low sample period, but we also want to get out of the EBB
* handler without tripping up again.
*
* This value picked after much experimentation.
*/
orig_period = max_period = sample_period = 400;
mtspr(SPRN_PMC4, pmc_sample_period(sample_period));
while (ebb_state.stats.ebb_count < 1000000) {
/*
* We are trying to get the EBB exception to race exactly with
* us entering the kernel to do the syscall. We then need the
* kernel to decide our timeslice is up and context switch to
* the other thread. When we come back our EBB will have been
* lost and we'll spin in this while loop forever.
*/
for (i = 0; i < 100000; i++)
sched_yield();
/* Change the sample period slightly to try and hit the race */
if (sample_period >= (orig_period + 200))
sample_period = orig_period;
else
sample_period++;
if (sample_period > max_period)
max_period = sample_period;
}
ebb_freeze_pmcs();
ebb_global_disable();
count_pmc(4, sample_period);
mtspr(SPRN_PMC4, 0xdead);
dump_summary_ebb_state();
dump_ebb_hw_state();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
/* We vary our sample period so we need extra fudge here */
FAIL_IF(!ebb_check_count(4, orig_period, 2 * (max_period - orig_period)));
return 0;
}
static int lost_exception(void)
{
return eat_cpu(test_body);
}
int main(void)
{
return test_harness(lost_exception, "lost_exception");
}

View File

@ -0,0 +1,91 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include "ebb.h"
/*
* Test counting multiple events using EBBs.
*/
int multi_counter(void)
{
struct event events[6];
int i, group_fd;
event_init_named(&events[0], 0x1001C, "PM_CMPLU_STALL_THRD");
event_init_named(&events[1], 0x2D016, "PM_CMPLU_STALL_FXU");
event_init_named(&events[2], 0x30006, "PM_CMPLU_STALL_OTHER_CMPL");
event_init_named(&events[3], 0x4000A, "PM_CMPLU_STALL");
event_init_named(&events[4], 0x600f4, "PM_RUN_CYC");
event_init_named(&events[5], 0x500fa, "PM_RUN_INST_CMPL");
event_leader_ebb_init(&events[0]);
for (i = 1; i < 6; i++)
event_ebb_init(&events[i]);
group_fd = -1;
for (i = 0; i < 6; i++) {
events[i].attr.exclude_kernel = 1;
events[i].attr.exclude_hv = 1;
events[i].attr.exclude_idle = 1;
FAIL_IF(event_open_with_group(&events[i], group_fd));
if (group_fd == -1)
group_fd = events[0].fd;
}
ebb_enable_pmc_counting(1);
ebb_enable_pmc_counting(2);
ebb_enable_pmc_counting(3);
ebb_enable_pmc_counting(4);
ebb_enable_pmc_counting(5);
ebb_enable_pmc_counting(6);
setup_ebb_handler(standard_ebb_callee);
FAIL_IF(ioctl(events[0].fd, PERF_EVENT_IOC_ENABLE, PERF_IOC_FLAG_GROUP));
FAIL_IF(event_read(&events[0]));
ebb_global_enable();
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
mtspr(SPRN_PMC2, pmc_sample_period(sample_period));
mtspr(SPRN_PMC3, pmc_sample_period(sample_period));
mtspr(SPRN_PMC4, pmc_sample_period(sample_period));
mtspr(SPRN_PMC5, pmc_sample_period(sample_period));
mtspr(SPRN_PMC6, pmc_sample_period(sample_period));
while (ebb_state.stats.ebb_count < 50) {
FAIL_IF(core_busy_loop());
FAIL_IF(ebb_check_mmcr0());
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
count_pmc(2, sample_period);
count_pmc(3, sample_period);
count_pmc(4, sample_period);
count_pmc(5, sample_period);
count_pmc(6, sample_period);
dump_ebb_state();
for (i = 0; i < 6; i++)
event_close(&events[i]);
FAIL_IF(ebb_state.stats.ebb_count == 0);
return 0;
}
int main(void)
{
return test_harness(multi_counter, "multi_counter");
}

View File

@ -0,0 +1,109 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include "ebb.h"
/*
* Test running multiple EBB using processes at once on a single CPU. They
* should all run happily without interfering with each other.
*/
static bool child_should_exit;
static void sigint_handler(int signal)
{
child_should_exit = true;
}
struct sigaction sigint_action = {
.sa_handler = sigint_handler,
};
static int cycles_child(void)
{
struct event event;
if (sigaction(SIGINT, &sigint_action, NULL)) {
perror("sigaction");
return 1;
}
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
while (!child_should_exit) {
FAIL_IF(core_busy_loop());
FAIL_IF(ebb_check_mmcr0());
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_summary_ebb_state();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
return 0;
}
#define NR_CHILDREN 4
int multi_ebb_procs(void)
{
pid_t pids[NR_CHILDREN];
int cpu, rc, i;
cpu = pick_online_cpu();
FAIL_IF(cpu < 0);
FAIL_IF(bind_to_cpu(cpu));
for (i = 0; i < NR_CHILDREN; i++) {
pids[i] = fork();
if (pids[i] == 0)
exit(cycles_child());
}
/* Have them all run for "a while" */
sleep(10);
rc = 0;
for (i = 0; i < NR_CHILDREN; i++) {
/* Tell them to stop */
kill(pids[i], SIGINT);
/* And wait */
rc |= wait_for_child(pids[i]);
}
return rc;
}
int main(void)
{
return test_harness(multi_ebb_procs, "multi_ebb_procs");
}

View File

@ -0,0 +1,61 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>
#include <signal.h>
#include "ebb.h"
/* Test that things work sanely if we have no handler */
static int no_handler_test(void)
{
struct event event;
u64 val;
int i;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
FAIL_IF(ebb_event_enable(&event));
val = mfspr(SPRN_EBBHR);
FAIL_IF(val != 0);
/* Make sure it overflows quickly */
sample_period = 1000;
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
/* Spin to make sure the event has time to overflow */
for (i = 0; i < 1000; i++)
mb();
dump_ebb_state();
/* We expect to see the PMU frozen & PMAO set */
val = mfspr(SPRN_MMCR0);
FAIL_IF(val != 0x0000000080000080);
event_close(&event);
dump_ebb_state();
/* The real test is that we never took an EBB at 0x0 */
return 0;
}
int main(void)
{
return test_harness(no_handler_test,"no_handler_test");
}

View File

@ -0,0 +1,106 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <sched.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include "ebb.h"
/*
* Test that the kernel properly handles PMAE across context switches.
*
* We test this by calling into the kernel inside our EBB handler, where PMAE
* is clear. A cpu eater companion thread is running on the same CPU as us to
* encourage the scheduler to switch us.
*
* The kernel must make sure that when it context switches us back in, it
* honours the fact that we had PMAE clear.
*
* Observed to hit the failing case on the first EBB with a broken kernel.
*/
static bool mmcr0_mismatch;
static uint64_t before, after;
static void syscall_ebb_callee(void)
{
uint64_t val;
val = mfspr(SPRN_BESCR);
if (!(val & BESCR_PMEO)) {
ebb_state.stats.spurious++;
goto out;
}
ebb_state.stats.ebb_count++;
count_pmc(1, sample_period);
before = mfspr(SPRN_MMCR0);
/* Try and get ourselves scheduled, to force a PMU context switch */
sched_yield();
after = mfspr(SPRN_MMCR0);
if (before != after)
mmcr0_mismatch = true;
out:
reset_ebb();
}
static int test_body(void)
{
struct event event;
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
setup_ebb_handler(syscall_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
while (ebb_state.stats.ebb_count < 20 && !mmcr0_mismatch)
FAIL_IF(core_busy_loop());
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
if (mmcr0_mismatch)
printf("Saw MMCR0 before 0x%lx after 0x%lx\n", before, after);
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
FAIL_IF(mmcr0_mismatch);
return 0;
}
int pmae_handling(void)
{
return eat_cpu(test_body);
}
int main(void)
{
return test_harness(pmae_handling, "pmae_handling");
}

View File

@ -0,0 +1,93 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include "ebb.h"
/*
* Test that PMC5 & 6 are frozen (ie. don't overflow) when they are not being
* used. Tests the MMCR0_FC56 logic in the kernel.
*/
static int pmc56_overflowed;
static void ebb_callee(void)
{
uint64_t val;
val = mfspr(SPRN_BESCR);
if (!(val & BESCR_PMEO)) {
ebb_state.stats.spurious++;
goto out;
}
ebb_state.stats.ebb_count++;
count_pmc(2, sample_period);
val = mfspr(SPRN_PMC5);
if (val >= COUNTER_OVERFLOW)
pmc56_overflowed++;
count_pmc(5, COUNTER_OVERFLOW);
val = mfspr(SPRN_PMC6);
if (val >= COUNTER_OVERFLOW)
pmc56_overflowed++;
count_pmc(6, COUNTER_OVERFLOW);
out:
reset_ebb();
}
int pmc56_overflow(void)
{
struct event event;
/* Use PMC2 so we set PMCjCE, which enables PMC5/6 */
event_init(&event, 0x2001e);
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open(&event));
setup_ebb_handler(ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
mtspr(SPRN_PMC5, 0);
mtspr(SPRN_PMC6, 0);
while (ebb_state.stats.ebb_count < 10)
FAIL_IF(core_busy_loop());
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(2, sample_period);
dump_ebb_state();
printf("PMC5/6 overflow %d\n", pmc56_overflowed);
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0 || pmc56_overflowed != 0);
return 0;
}
int main(void)
{
return test_harness(pmc56_overflow, "pmc56_overflow");
}

View File

@ -0,0 +1,49 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#ifndef _SELFTESTS_POWERPC_REG_H
#define _SELFTESTS_POWERPC_REG_H
#define __stringify_1(x) #x
#define __stringify(x) __stringify_1(x)
#define mfspr(rn) ({unsigned long rval; \
asm volatile("mfspr %0," __stringify(rn) \
: "=r" (rval)); rval; })
#define mtspr(rn, v) asm volatile("mtspr " __stringify(rn) ",%0" : \
: "r" ((unsigned long)(v)) \
: "memory")
#define mb() asm volatile("sync" : : : "memory");
#define SPRN_MMCR2 769
#define SPRN_MMCRA 770
#define SPRN_MMCR0 779
#define MMCR0_PMAO 0x00000080
#define MMCR0_PMAE 0x04000000
#define MMCR0_FC 0x80000000
#define SPRN_EBBHR 804
#define SPRN_EBBRR 805
#define SPRN_BESCR 806 /* Branch event status & control register */
#define SPRN_BESCRS 800 /* Branch event status & control set (1 bits set to 1) */
#define SPRN_BESCRSU 801 /* Branch event status & control set upper */
#define SPRN_BESCRR 802 /* Branch event status & control REset (1 bits set to 0) */
#define SPRN_BESCRRU 803 /* Branch event status & control REset upper */
#define BESCR_PMEO 0x1 /* PMU Event-based exception Occurred */
#define BESCR_PME (0x1ul << 32) /* PMU Event-based exception Enable */
#define SPRN_PMC1 771
#define SPRN_PMC2 772
#define SPRN_PMC3 773
#define SPRN_PMC4 774
#define SPRN_PMC5 775
#define SPRN_PMC6 776
#define SPRN_SIAR 780
#define SPRN_SDAR 781
#define SPRN_SIER 768
#endif /* _SELFTESTS_POWERPC_REG_H */

View File

@ -0,0 +1,39 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <stdio.h>
#include <stdlib.h>
#include "ebb.h"
#include "reg.h"
/*
* Test basic access to the EBB regs, they should be user accessible with no
* kernel interaction required.
*/
int reg_access(void)
{
uint64_t val, expected;
expected = 0x8000000100000000ull;
mtspr(SPRN_BESCR, expected);
val = mfspr(SPRN_BESCR);
FAIL_IF(val != expected);
expected = 0x0000000001000000ull;
mtspr(SPRN_EBBHR, expected);
val = mfspr(SPRN_EBBHR);
FAIL_IF(val != expected);
return 0;
}
int main(void)
{
return test_harness(reg_access, "reg_access");
}

View File

@ -0,0 +1,91 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests a pinned per-task event vs an EBB - in that order. The pinned per-task
* event should prevent the EBB event from being enabled.
*/
static int setup_child_event(struct event *event, pid_t child_pid)
{
event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
event->attr.pinned = 1;
event->attr.exclude_kernel = 1;
event->attr.exclude_hv = 1;
event->attr.exclude_idle = 1;
FAIL_IF(event_open_with_pid(event, child_pid));
FAIL_IF(event_enable(event));
return 0;
}
int task_event_pinned_vs_ebb(void)
{
union pipe read_pipe, write_pipe;
struct event event;
pid_t pid;
int rc;
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(ebb_child(write_pipe, read_pipe));
}
/* We setup the task event first */
rc = setup_child_event(&event, pid);
if (rc) {
kill_child_and_wait(pid);
return rc;
}
/* Signal the child to install its EBB event and wait */
if (sync_with_child(read_pipe, write_pipe))
/* If it fails, wait for it to exit */
goto wait;
/* Signal the child to run */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
wait:
/* We expect it to fail to read the event */
FAIL_IF(wait_for_child(pid) != 2);
FAIL_IF(event_disable(&event));
FAIL_IF(event_read(&event));
event_report(&event);
FAIL_IF(event.result.value == 0);
/*
* For reasons I don't understand enabled is usually just slightly
* lower than running. Would be good to confirm why.
*/
FAIL_IF(event.result.enabled == 0);
FAIL_IF(event.result.running == 0);
return 0;
}
int main(void)
{
return test_harness(task_event_pinned_vs_ebb, "task_event_pinned_vs_ebb");
}

View File

@ -0,0 +1,83 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests a per-task event vs an EBB - in that order. The EBB should push the
* per-task event off the PMU.
*/
static int setup_child_event(struct event *event, pid_t child_pid)
{
event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
event->attr.exclude_kernel = 1;
event->attr.exclude_hv = 1;
event->attr.exclude_idle = 1;
FAIL_IF(event_open_with_pid(event, child_pid));
FAIL_IF(event_enable(event));
return 0;
}
int task_event_vs_ebb(void)
{
union pipe read_pipe, write_pipe;
struct event event;
pid_t pid;
int rc;
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(ebb_child(write_pipe, read_pipe));
}
/* We setup the task event first */
rc = setup_child_event(&event, pid);
if (rc) {
kill_child_and_wait(pid);
return rc;
}
/* Signal the child to install its EBB event and wait */
if (sync_with_child(read_pipe, write_pipe))
/* If it fails, wait for it to exit */
goto wait;
/* Signal the child to run */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
wait:
/* The EBB event should push the task event off so the child should succeed */
FAIL_IF(wait_for_child(pid));
FAIL_IF(event_disable(&event));
FAIL_IF(event_read(&event));
event_report(&event);
/* The task event may have run, or not so we can't assert anything about it */
return 0;
}
int main(void)
{
return test_harness(task_event_vs_ebb, "task_event_vs_ebb");
}

View File

@ -0,0 +1,300 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include "trace.h"
struct trace_buffer *trace_buffer_allocate(u64 size)
{
struct trace_buffer *tb;
if (size < sizeof(*tb)) {
fprintf(stderr, "Error: trace buffer too small\n");
return NULL;
}
tb = mmap(NULL, size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (tb == MAP_FAILED) {
perror("mmap");
return NULL;
}
tb->size = size;
tb->tail = tb->data;
tb->overflow = false;
return tb;
}
static bool trace_check_bounds(struct trace_buffer *tb, void *p)
{
return p < ((void *)tb + tb->size);
}
static bool trace_check_alloc(struct trace_buffer *tb, void *p)
{
/*
* If we ever overflowed don't allow any more input. This prevents us
* from dropping a large item and then later logging a small one. The
* buffer should just stop when overflow happened, not be patchy. If
* you're overflowing, make your buffer bigger.
*/
if (tb->overflow)
return false;
if (!trace_check_bounds(tb, p)) {
tb->overflow = true;
return false;
}
return true;
}
static void *trace_alloc(struct trace_buffer *tb, int bytes)
{
void *p, *newtail;
p = tb->tail;
newtail = tb->tail + bytes;
if (!trace_check_alloc(tb, newtail))
return NULL;
tb->tail = newtail;
return p;
}
static struct trace_entry *trace_alloc_entry(struct trace_buffer *tb, int payload_size)
{
struct trace_entry *e;
e = trace_alloc(tb, sizeof(*e) + payload_size);
if (e)
e->length = payload_size;
return e;
}
int trace_log_reg(struct trace_buffer *tb, u64 reg, u64 value)
{
struct trace_entry *e;
u64 *p;
e = trace_alloc_entry(tb, sizeof(reg) + sizeof(value));
if (!e)
return -ENOSPC;
e->type = TRACE_TYPE_REG;
p = (u64 *)e->data;
*p++ = reg;
*p++ = value;
return 0;
}
int trace_log_counter(struct trace_buffer *tb, u64 value)
{
struct trace_entry *e;
u64 *p;
e = trace_alloc_entry(tb, sizeof(value));
if (!e)
return -ENOSPC;
e->type = TRACE_TYPE_COUNTER;
p = (u64 *)e->data;
*p++ = value;
return 0;
}
int trace_log_string(struct trace_buffer *tb, char *str)
{
struct trace_entry *e;
char *p;
int len;
len = strlen(str);
/* We NULL terminate to make printing easier */
e = trace_alloc_entry(tb, len + 1);
if (!e)
return -ENOSPC;
e->type = TRACE_TYPE_STRING;
p = (char *)e->data;
memcpy(p, str, len);
p += len;
*p = '\0';
return 0;
}
int trace_log_indent(struct trace_buffer *tb)
{
struct trace_entry *e;
e = trace_alloc_entry(tb, 0);
if (!e)
return -ENOSPC;
e->type = TRACE_TYPE_INDENT;
return 0;
}
int trace_log_outdent(struct trace_buffer *tb)
{
struct trace_entry *e;
e = trace_alloc_entry(tb, 0);
if (!e)
return -ENOSPC;
e->type = TRACE_TYPE_OUTDENT;
return 0;
}
static void trace_print_header(int seq, int prefix)
{
printf("%*s[%d]: ", prefix, "", seq);
}
static char *trace_decode_reg(int reg)
{
switch (reg) {
case 769: return "SPRN_MMCR2"; break;
case 770: return "SPRN_MMCRA"; break;
case 779: return "SPRN_MMCR0"; break;
case 804: return "SPRN_EBBHR"; break;
case 805: return "SPRN_EBBRR"; break;
case 806: return "SPRN_BESCR"; break;
case 800: return "SPRN_BESCRS"; break;
case 801: return "SPRN_BESCRSU"; break;
case 802: return "SPRN_BESCRR"; break;
case 803: return "SPRN_BESCRRU"; break;
case 771: return "SPRN_PMC1"; break;
case 772: return "SPRN_PMC2"; break;
case 773: return "SPRN_PMC3"; break;
case 774: return "SPRN_PMC4"; break;
case 775: return "SPRN_PMC5"; break;
case 776: return "SPRN_PMC6"; break;
case 780: return "SPRN_SIAR"; break;
case 781: return "SPRN_SDAR"; break;
case 768: return "SPRN_SIER"; break;
}
return NULL;
}
static void trace_print_reg(struct trace_entry *e)
{
u64 *p, *reg, *value;
char *name;
p = (u64 *)e->data;
reg = p++;
value = p;
name = trace_decode_reg(*reg);
if (name)
printf("register %-10s = 0x%016llx\n", name, *value);
else
printf("register %lld = 0x%016llx\n", *reg, *value);
}
static void trace_print_counter(struct trace_entry *e)
{
u64 *value;
value = (u64 *)e->data;
printf("counter = %lld\n", *value);
}
static void trace_print_string(struct trace_entry *e)
{
char *str;
str = (char *)e->data;
puts(str);
}
#define BASE_PREFIX 2
#define PREFIX_DELTA 8
static void trace_print_entry(struct trace_entry *e, int seq, int *prefix)
{
switch (e->type) {
case TRACE_TYPE_REG:
trace_print_header(seq, *prefix);
trace_print_reg(e);
break;
case TRACE_TYPE_COUNTER:
trace_print_header(seq, *prefix);
trace_print_counter(e);
break;
case TRACE_TYPE_STRING:
trace_print_header(seq, *prefix);
trace_print_string(e);
break;
case TRACE_TYPE_INDENT:
trace_print_header(seq, *prefix);
puts("{");
*prefix += PREFIX_DELTA;
break;
case TRACE_TYPE_OUTDENT:
*prefix -= PREFIX_DELTA;
if (*prefix < BASE_PREFIX)
*prefix = BASE_PREFIX;
trace_print_header(seq, *prefix);
puts("}");
break;
default:
trace_print_header(seq, *prefix);
printf("entry @ %p type %d\n", e, e->type);
break;
}
}
void trace_buffer_print(struct trace_buffer *tb)
{
struct trace_entry *e;
int i, prefix;
void *p;
printf("Trace buffer dump:\n");
printf(" address %p \n", tb);
printf(" tail %p\n", tb->tail);
printf(" size %llu\n", tb->size);
printf(" overflow %s\n", tb->overflow ? "TRUE" : "false");
printf(" Content:\n");
p = tb->data;
i = 0;
prefix = BASE_PREFIX;
while (trace_check_bounds(tb, p) && p < tb->tail) {
e = p;
trace_print_entry(e, i, &prefix);
i++;
p = (void *)e + sizeof(*e) + e->length;
}
}
void trace_print_location(struct trace_buffer *tb)
{
printf("Trace buffer 0x%llx bytes @ %p\n", tb->size, tb);
}

View File

@ -0,0 +1,41 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#ifndef _SELFTESTS_POWERPC_PMU_EBB_TRACE_H
#define _SELFTESTS_POWERPC_PMU_EBB_TRACE_H
#include "utils.h"
#define TRACE_TYPE_REG 1
#define TRACE_TYPE_COUNTER 2
#define TRACE_TYPE_STRING 3
#define TRACE_TYPE_INDENT 4
#define TRACE_TYPE_OUTDENT 5
struct trace_entry
{
u8 type;
u8 length;
u8 data[0];
};
struct trace_buffer
{
u64 size;
bool overflow;
void *tail;
u8 data[0];
};
struct trace_buffer *trace_buffer_allocate(u64 size);
int trace_log_reg(struct trace_buffer *tb, u64 reg, u64 value);
int trace_log_counter(struct trace_buffer *tb, u64 value);
int trace_log_string(struct trace_buffer *tb, char *str);
int trace_log_indent(struct trace_buffer *tb);
int trace_log_outdent(struct trace_buffer *tb);
void trace_buffer_print(struct trace_buffer *tb);
void trace_print_location(struct trace_buffer *tb);
#endif /* _SELFTESTS_POWERPC_PMU_EBB_TRACE_H */

View File

@ -39,7 +39,13 @@ void event_init_named(struct event *e, u64 config, char *name)
event_init_opts(e, config, PERF_TYPE_RAW, name);
}
void event_init(struct event *e, u64 config)
{
event_init_opts(e, config, PERF_TYPE_RAW, "event");
}
#define PERF_CURRENT_PID 0
#define PERF_NO_PID -1
#define PERF_NO_CPU -1
#define PERF_NO_GROUP -1
@ -59,6 +65,16 @@ int event_open_with_group(struct event *e, int group_fd)
return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, group_fd);
}
int event_open_with_pid(struct event *e, pid_t pid)
{
return event_open_with_options(e, pid, PERF_NO_CPU, PERF_NO_GROUP);
}
int event_open_with_cpu(struct event *e, int cpu)
{
return event_open_with_options(e, PERF_NO_PID, cpu, PERF_NO_GROUP);
}
int event_open(struct event *e)
{
return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, PERF_NO_GROUP);
@ -69,6 +85,16 @@ void event_close(struct event *e)
close(e->fd);
}
int event_enable(struct event *e)
{
return ioctl(e->fd, PERF_EVENT_IOC_ENABLE);
}
int event_disable(struct event *e)
{
return ioctl(e->fd, PERF_EVENT_IOC_DISABLE);
}
int event_reset(struct event *e)
{
return ioctl(e->fd, PERF_EVENT_IOC_RESET);

View File

@ -29,8 +29,12 @@ void event_init_named(struct event *e, u64 config, char *name);
void event_init_opts(struct event *e, u64 config, int type, char *name);
int event_open_with_options(struct event *e, pid_t pid, int cpu, int group_fd);
int event_open_with_group(struct event *e, int group_fd);
int event_open_with_pid(struct event *e, pid_t pid);
int event_open_with_cpu(struct event *e, int cpu);
int event_open(struct event *e);
void event_close(struct event *e);
int event_enable(struct event *e);
int event_disable(struct event *e);
int event_reset(struct event *e);
int event_read(struct event *e);
void event_report_justified(struct event *e, int name_width, int result_width);

View File

@ -0,0 +1,252 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#define _GNU_SOURCE /* For CPU_ZERO etc. */
#include <errno.h>
#include <sched.h>
#include <setjmp.h>
#include <stdlib.h>
#include <sys/wait.h>
#include "utils.h"
#include "lib.h"
int pick_online_cpu(void)
{
cpu_set_t mask;
int cpu;
CPU_ZERO(&mask);
if (sched_getaffinity(0, sizeof(mask), &mask)) {
perror("sched_getaffinity");
return -1;
}
/* We prefer a primary thread, but skip 0 */
for (cpu = 8; cpu < CPU_SETSIZE; cpu += 8)
if (CPU_ISSET(cpu, &mask))
return cpu;
/* Search for anything, but in reverse */
for (cpu = CPU_SETSIZE - 1; cpu >= 0; cpu--)
if (CPU_ISSET(cpu, &mask))
return cpu;
printf("No cpus in affinity mask?!\n");
return -1;
}
int bind_to_cpu(int cpu)
{
cpu_set_t mask;
printf("Binding to cpu %d\n", cpu);
CPU_ZERO(&mask);
CPU_SET(cpu, &mask);
return sched_setaffinity(0, sizeof(mask), &mask);
}
#define PARENT_TOKEN 0xAA
#define CHILD_TOKEN 0x55
int sync_with_child(union pipe read_pipe, union pipe write_pipe)
{
char c = PARENT_TOKEN;
FAIL_IF(write(write_pipe.write_fd, &c, 1) != 1);
FAIL_IF(read(read_pipe.read_fd, &c, 1) != 1);
if (c != CHILD_TOKEN) /* sometimes expected */
return 1;
return 0;
}
int wait_for_parent(union pipe read_pipe)
{
char c;
FAIL_IF(read(read_pipe.read_fd, &c, 1) != 1);
FAIL_IF(c != PARENT_TOKEN);
return 0;
}
int notify_parent(union pipe write_pipe)
{
char c = CHILD_TOKEN;
FAIL_IF(write(write_pipe.write_fd, &c, 1) != 1);
return 0;
}
int notify_parent_of_error(union pipe write_pipe)
{
char c = ~CHILD_TOKEN;
FAIL_IF(write(write_pipe.write_fd, &c, 1) != 1);
return 0;
}
int wait_for_child(pid_t child_pid)
{
int rc;
if (waitpid(child_pid, &rc, 0) == -1) {
perror("waitpid");
return 1;
}
if (WIFEXITED(rc))
rc = WEXITSTATUS(rc);
else
rc = 1; /* Signal or other */
return rc;
}
int kill_child_and_wait(pid_t child_pid)
{
kill(child_pid, SIGTERM);
return wait_for_child(child_pid);
}
static int eat_cpu_child(union pipe read_pipe, union pipe write_pipe)
{
volatile int i = 0;
/*
* We are just here to eat cpu and die. So make sure we can be killed,
* and also don't do any custom SIGTERM handling.
*/
signal(SIGTERM, SIG_DFL);
notify_parent(write_pipe);
wait_for_parent(read_pipe);
/* Soak up cpu forever */
while (1) i++;
return 0;
}
pid_t eat_cpu(int (test_function)(void))
{
union pipe read_pipe, write_pipe;
int cpu, rc;
pid_t pid;
cpu = pick_online_cpu();
FAIL_IF(cpu < 0);
FAIL_IF(bind_to_cpu(cpu));
if (pipe(read_pipe.fds) == -1)
return -1;
if (pipe(write_pipe.fds) == -1)
return -1;
pid = fork();
if (pid == 0)
exit(eat_cpu_child(write_pipe, read_pipe));
if (sync_with_child(read_pipe, write_pipe)) {
rc = -1;
goto out;
}
printf("main test running as pid %d\n", getpid());
rc = test_function();
out:
kill(pid, SIGKILL);
return rc;
}
struct addr_range libc, vdso;
int parse_proc_maps(void)
{
char execute, name[128];
uint64_t start, end;
FILE *f;
int rc;
f = fopen("/proc/self/maps", "r");
if (!f) {
perror("fopen");
return -1;
}
do {
/* This skips line with no executable which is what we want */
rc = fscanf(f, "%lx-%lx %*c%*c%c%*c %*x %*d:%*d %*d %127s\n",
&start, &end, &execute, name);
if (rc <= 0)
break;
if (execute != 'x')
continue;
if (strstr(name, "libc")) {
libc.first = start;
libc.last = end - 1;
} else if (strstr(name, "[vdso]")) {
vdso.first = start;
vdso.last = end - 1;
}
} while(1);
fclose(f);
return 0;
}
#define PARANOID_PATH "/proc/sys/kernel/perf_event_paranoid"
bool require_paranoia_below(int level)
{
unsigned long current;
char *end, buf[16];
FILE *f;
int rc;
rc = -1;
f = fopen(PARANOID_PATH, "r");
if (!f) {
perror("fopen");
goto out;
}
if (!fgets(buf, sizeof(buf), f)) {
printf("Couldn't read " PARANOID_PATH "?\n");
goto out_close;
}
current = strtoul(buf, &end, 10);
if (end == buf) {
printf("Couldn't parse " PARANOID_PATH "?\n");
goto out_close;
}
if (current >= level)
goto out;
rc = 0;
out_close:
fclose(f);
out:
return rc;
}

View File

@ -0,0 +1,41 @@
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#ifndef __SELFTESTS_POWERPC_PMU_LIB_H
#define __SELFTESTS_POWERPC_PMU_LIB_H
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
union pipe {
struct {
int read_fd;
int write_fd;
};
int fds[2];
};
extern int pick_online_cpu(void);
extern int bind_to_cpu(int cpu);
extern int kill_child_and_wait(pid_t child_pid);
extern int wait_for_child(pid_t child_pid);
extern int sync_with_child(union pipe read_pipe, union pipe write_pipe);
extern int wait_for_parent(union pipe read_pipe);
extern int notify_parent(union pipe write_pipe);
extern int notify_parent_of_error(union pipe write_pipe);
extern pid_t eat_cpu(int (test_function)(void));
extern bool require_paranoia_below(int level);
struct addr_range {
uint64_t first, last;
};
extern struct addr_range libc, vdso;
int parse_proc_maps(void);
#endif /* __SELFTESTS_POWERPC_PMU_LIB_H */