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Diffstat (limited to 'arch/s390/kernel/perf_pai_crypto.c')
-rw-r--r--arch/s390/kernel/perf_pai_crypto.c83
1 files changed, 55 insertions, 28 deletions
diff --git a/arch/s390/kernel/perf_pai_crypto.c b/arch/s390/kernel/perf_pai_crypto.c
index bf8a672b15a4..823d652e3917 100644
--- a/arch/s390/kernel/perf_pai_crypto.c
+++ b/arch/s390/kernel/perf_pai_crypto.c
@@ -98,6 +98,7 @@ static void paicrypt_event_destroy(struct perf_event *event)
event->attr.config, event->cpu,
cpump->active_events, cpump->mode,
refcount_read(&cpump->refcnt));
+ free_page(PAI_SAVE_AREA(event));
if (refcount_dec_and_test(&cpump->refcnt)) {
debug_sprintf_event(cfm_dbg, 4, "%s page %#lx save %p\n",
__func__, (unsigned long)cpump->page,
@@ -260,6 +261,7 @@ static int paicrypt_event_init(struct perf_event *event)
{
struct perf_event_attr *a = &event->attr;
struct paicrypt_map *cpump;
+ int rc = 0;
/* PAI crypto PMU registered as PERF_TYPE_RAW, check event type */
if (a->type != PERF_TYPE_RAW && event->pmu->type != a->type)
@@ -274,10 +276,21 @@ static int paicrypt_event_init(struct perf_event *event)
/* Allow only CRYPTO_ALL for sampling. */
if (a->sample_period && a->config != PAI_CRYPTO_BASE)
return -EINVAL;
+ /* Get a page to store last counter values for sampling */
+ if (a->sample_period) {
+ PAI_SAVE_AREA(event) = get_zeroed_page(GFP_KERNEL);
+ if (!PAI_SAVE_AREA(event)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ }
cpump = paicrypt_busy(event);
- if (IS_ERR(cpump))
- return PTR_ERR(cpump);
+ if (IS_ERR(cpump)) {
+ free_page(PAI_SAVE_AREA(event));
+ rc = PTR_ERR(cpump);
+ goto out;
+ }
event->destroy = paicrypt_event_destroy;
@@ -293,7 +306,8 @@ static int paicrypt_event_init(struct perf_event *event)
}
static_branch_inc(&pai_key);
- return 0;
+out:
+ return rc;
}
static void paicrypt_read(struct perf_event *event)
@@ -310,20 +324,15 @@ static void paicrypt_read(struct perf_event *event)
static void paicrypt_start(struct perf_event *event, int flags)
{
+ struct paicrypt_mapptr *mp = this_cpu_ptr(paicrypt_root.mapptr);
+ struct paicrypt_map *cpump = mp->mapptr;
u64 sum;
- /* Event initialization sets last_tag to 0. When later on the events
- * are deleted and re-added, do not reset the event count value to zero.
- * Events are added, deleted and re-added when 2 or more events
- * are active at the same time.
- */
if (!event->attr.sample_period) { /* Counting */
- if (!event->hw.last_tag) {
- event->hw.last_tag = 1;
- sum = paicrypt_getall(event); /* Get current value */
- local64_set(&event->hw.prev_count, sum);
- }
+ sum = paicrypt_getall(event); /* Get current value */
+ local64_set(&event->hw.prev_count, sum);
} else { /* Sampling */
+ cpump->event = event;
perf_sched_cb_inc(event->pmu);
}
}
@@ -339,7 +348,6 @@ static int paicrypt_add(struct perf_event *event, int flags)
WRITE_ONCE(S390_lowcore.ccd, ccd);
local_ctl_set_bit(0, CR0_CRYPTOGRAPHY_COUNTER_BIT);
}
- cpump->event = event;
if (flags & PERF_EF_START)
paicrypt_start(event, PERF_EF_RELOAD);
event->hw.state = 0;
@@ -367,23 +375,34 @@ static void paicrypt_del(struct perf_event *event, int flags)
}
}
-/* Create raw data and save it in buffer. Returns number of bytes copied.
- * Saves only positive counter entries of the form
+/* Create raw data and save it in buffer. Calculate the delta for each
+ * counter between this invocation and the last invocation.
+ * Returns number of bytes copied.
+ * Saves only entries with positive counter difference of the form
* 2 bytes: Number of counter
* 8 bytes: Value of counter
*/
static size_t paicrypt_copy(struct pai_userdata *userdata, unsigned long *page,
- bool exclude_user, bool exclude_kernel)
+ unsigned long *page_old, bool exclude_user,
+ bool exclude_kernel)
{
int i, outidx = 0;
for (i = 1; i <= paicrypt_cnt; i++) {
- u64 val = 0;
+ u64 val = 0, val_old = 0;
- if (!exclude_kernel)
+ if (!exclude_kernel) {
val += paicrypt_getctr(page, i, true);
- if (!exclude_user)
+ val_old += paicrypt_getctr(page_old, i, true);
+ }
+ if (!exclude_user) {
val += paicrypt_getctr(page, i, false);
+ val_old += paicrypt_getctr(page_old, i, false);
+ }
+ if (val >= val_old)
+ val -= val_old;
+ else
+ val = (~0ULL - val_old) + val + 1;
if (val) {
userdata[outidx].num = i;
userdata[outidx].value = val;
@@ -426,8 +445,8 @@ static int paicrypt_push_sample(size_t rawsize, struct paicrypt_map *cpump,
overflow = perf_event_overflow(event, &data, &regs);
perf_event_update_userpage(event);
- /* Clear lowcore page after read */
- memset(cpump->page, 0, PAGE_SIZE);
+ /* Save crypto counter lowcore page after reading event data. */
+ memcpy((void *)PAI_SAVE_AREA(event), cpump->page, PAGE_SIZE);
return overflow;
}
@@ -443,6 +462,7 @@ static int paicrypt_have_sample(void)
if (!event) /* No event active */
return 0;
rawsize = paicrypt_copy(cpump->save, cpump->page,
+ (unsigned long *)PAI_SAVE_AREA(event),
cpump->event->attr.exclude_user,
cpump->event->attr.exclude_kernel);
if (rawsize) /* No incremented counters */
@@ -694,6 +714,12 @@ static int __init attr_event_init_one(struct attribute **attrs, int num)
{
struct perf_pmu_events_attr *pa;
+ /* Index larger than array_size, no counter name available */
+ if (num >= ARRAY_SIZE(paicrypt_ctrnames)) {
+ attrs[num] = NULL;
+ return 0;
+ }
+
pa = kzalloc(sizeof(*pa), GFP_KERNEL);
if (!pa)
return -ENOMEM;
@@ -714,14 +740,13 @@ static int __init attr_event_init(void)
struct attribute **attrs;
int ret, i;
- attrs = kmalloc_array(ARRAY_SIZE(paicrypt_ctrnames) + 1, sizeof(*attrs),
- GFP_KERNEL);
+ attrs = kmalloc_array(paicrypt_cnt + 2, sizeof(*attrs), GFP_KERNEL);
if (!attrs)
return -ENOMEM;
- for (i = 0; i < ARRAY_SIZE(paicrypt_ctrnames); i++) {
+ for (i = 0; i <= paicrypt_cnt; i++) {
ret = attr_event_init_one(attrs, i);
if (ret) {
- attr_event_free(attrs, i - 1);
+ attr_event_free(attrs, i);
return ret;
}
}
@@ -742,8 +767,10 @@ static int __init paicrypt_init(void)
paicrypt_cnt = ib.num_cc;
if (paicrypt_cnt == 0)
return 0;
- if (paicrypt_cnt >= PAI_CRYPTO_MAXCTR)
- paicrypt_cnt = PAI_CRYPTO_MAXCTR - 1;
+ if (paicrypt_cnt >= PAI_CRYPTO_MAXCTR) {
+ pr_err("Too many PMU pai_crypto counters %d\n", paicrypt_cnt);
+ return -E2BIG;
+ }
rc = attr_event_init(); /* Export known PAI crypto events */
if (rc) {
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-01 05:33:23 +0000