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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /tools/testing/selftests/powerpc/pmu/ebb/ebb.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/powerpc/pmu/ebb/ebb.c')
-rw-r--r--tools/testing/selftests/powerpc/pmu/ebb/ebb.c485
1 files changed, 485 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/pmu/ebb/ebb.c b/tools/testing/selftests/powerpc/pmu/ebb/ebb.c
new file mode 100644
index 000000000..2694ae161
--- /dev/null
+++ b/tools/testing/selftests/powerpc/pmu/ebb/ebb.c
@@ -0,0 +1,485 @@
+/*
+ * 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 "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" \
+ "MMCR2 0x%016lx\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_MMCR2),
+ 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();
+}
+
+bool ebb_is_supported(void)
+{
+#ifdef PPC_FEATURE2_EBB
+ /* EBB requires at least POWER8 */
+ return have_hwcap2(PPC_FEATURE2_EBB);
+#else
+ return false;
+#endif
+}
+
+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 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();
+
+ 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);
+}