Linux-libre 4.6.2-gnu

1 files changed, 137 insertions, 96 deletions

diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c
index 9f9dfda9e..2da41b78c 100644
--- a/arch/powerpc/perf/hv-24x7.c
+++ b/arch/powerpc/perf/hv-24x7.c
@@ -27,20 +27,6 @@
 #include "hv-24x7-catalog.h"
 #include "hv-common.h"
 
-static const char *event_domain_suffix(unsigned domain)
-{
-	switch (domain) {
-#define DOMAIN(n, v, x, c)		\
-	case HV_PERF_DOMAIN_##n:	\
-		return "__" #n;
-#include "hv-24x7-domains.h"
-#undef DOMAIN
-	default:
-		WARN(1, "unknown domain %d\n", domain);
-		return "__UNKNOWN_DOMAIN_SUFFIX";
-	}
-}
-
 static bool domain_is_valid(unsigned domain)
 {
 	switch (domain) {
@@ -68,6 +54,24 @@ static bool is_physical_domain(unsigned domain)
 	}
 }
 
+static const char *domain_name(unsigned domain)
+{
+	if (!domain_is_valid(domain))
+		return NULL;
+
+	switch (domain) {
+	case HV_PERF_DOMAIN_PHYS_CHIP:		return "Physical Chip";
+	case HV_PERF_DOMAIN_PHYS_CORE:		return "Physical Core";
+	case HV_PERF_DOMAIN_VCPU_HOME_CORE:	return "VCPU Home Core";
+	case HV_PERF_DOMAIN_VCPU_HOME_CHIP:	return "VCPU Home Chip";
+	case HV_PERF_DOMAIN_VCPU_HOME_NODE:	return "VCPU Home Node";
+	case HV_PERF_DOMAIN_VCPU_REMOTE_NODE:	return "VCPU Remote Node";
+	}
+
+	WARN_ON_ONCE(domain);
+	return NULL;
+}
+
 static bool catalog_entry_domain_is_valid(unsigned domain)
 {
 	return is_physical_domain(domain);
@@ -101,6 +105,7 @@ static bool catalog_entry_domain_is_valid(unsigned domain)
 EVENT_DEFINE_RANGE_FORMAT(domain, config, 0, 3);
 /* u16 */
 EVENT_DEFINE_RANGE_FORMAT(core, config, 16, 31);
+EVENT_DEFINE_RANGE_FORMAT(chip, config, 16, 31);
 EVENT_DEFINE_RANGE_FORMAT(vcpu, config, 16, 31);
 /* u32, see "data_offset" */
 EVENT_DEFINE_RANGE_FORMAT(offset, config, 32, 63);
@@ -115,6 +120,7 @@ static struct attribute *format_attrs[] = {
 	&format_attr_domain.attr,
 	&format_attr_offset.attr,
 	&format_attr_core.attr,
+	&format_attr_chip.attr,
 	&format_attr_vcpu.attr,
 	&format_attr_lpar.attr,
 	NULL,
@@ -274,32 +280,70 @@ static unsigned long h_get_24x7_catalog_page(char page[],
 					version, index);
 }
 
-static unsigned core_domains[] = {
-	HV_PERF_DOMAIN_PHYS_CORE,
-	HV_PERF_DOMAIN_VCPU_HOME_CORE,
-	HV_PERF_DOMAIN_VCPU_HOME_CHIP,
-	HV_PERF_DOMAIN_VCPU_HOME_NODE,
-	HV_PERF_DOMAIN_VCPU_REMOTE_NODE,
-};
-/* chip event data always yeilds a single event, core yeilds multiple */
-#define MAX_EVENTS_PER_EVENT_DATA ARRAY_SIZE(core_domains)
-
+/*
+ * Each event we find in the catalog, will have a sysfs entry. Format the
+ * data for this sysfs entry based on the event's domain.
+ *
+ * Events belonging to the Chip domain can only be monitored in that domain.
+ * i.e the domain for these events is a fixed/knwon value.
+ *
+ * Events belonging to the Core domain can be monitored either in the physical
+ * core or in one of the virtual CPU domains. So the domain value for these
+ * events must be specified by the user (i.e is a required parameter). Format
+ * the Core events with 'domain=?' so the perf-tool can error check required
+ * parameters.
+ *
+ * NOTE: For the Core domain events, rather than making domain a required
+ *	 parameter we could default it to PHYS_CORE and allowe users to
+ *	 override the domain to one of the VCPU domains.
+ *
+ *	 However, this can make the interface a little inconsistent.
+ *
+ *	 If we set domain=2 (PHYS_CHIP) and allow user to override this field
+ *	 the user may be tempted to also modify the "offset=x" field in which
+ *	 can lead to confusing usage. Consider the HPM_PCYC (offset=0x18) and
+ *	 HPM_INST (offset=0x20) events. With:
+ *
+ *		perf stat -e hv_24x7/HPM_PCYC,offset=0x20/
+ *
+ *	we end up monitoring HPM_INST, while the command line has HPM_PCYC.
+ *
+ *	By not assigning a default value to the domain for the Core events,
+ *	we can have simple guidelines:
+ *
+ *		- Specifying values for parameters with "=?" is required.
+ *
+ *		- Specifying (i.e overriding) values for other parameters
+ *		  is undefined.
+ */
 static char *event_fmt(struct hv_24x7_event_data *event, unsigned domain)
 {
 	const char *sindex;
 	const char *lpar;
+	const char *domain_str;
+	char buf[8];
 
-	if (is_physical_domain(domain)) {
+	switch (domain) {
+	case HV_PERF_DOMAIN_PHYS_CHIP:
+		snprintf(buf, sizeof(buf), "%d", domain);
+		domain_str = buf;
+		lpar = "0x0";
+		sindex = "chip";
+		break;
+	case HV_PERF_DOMAIN_PHYS_CORE:
+		domain_str = "?";
 		lpar = "0x0";
 		sindex = "core";
-	} else {
+		break;
+	default:
+		domain_str = "?";
 		lpar = "?";
 		sindex = "vcpu";
 	}
 
 	return kasprintf(GFP_KERNEL,
-			"domain=0x%x,offset=0x%x,%s=?,lpar=%s",
-			domain,
+			"domain=%s,offset=0x%x,%s=?,lpar=%s",
+			domain_str,
 			be16_to_cpu(event->event_counter_offs) +
 				be16_to_cpu(event->event_group_record_offs),
 			sindex,
@@ -339,6 +383,15 @@ static struct attribute *device_str_attr_create_(char *name, char *str)
 	return &attr->attr.attr;
 }
 
+/*
+ * Allocate and initialize strings representing event attributes.
+ *
+ * NOTE: The strings allocated here are never destroyed and continue to
+ *	 exist till shutdown. This is to allow us to create as many events
+ *	 from the catalog as possible, even if we encounter errors with some.
+ *	 In case of changes to error paths in future, these may need to be
+ *	 freed by the caller.
+ */
 static struct attribute *device_str_attr_create(char *name, int name_max,
 						int name_nonce,
 						char *str, size_t str_max)
@@ -370,16 +423,6 @@ out_s:
 	return NULL;
 }
 
-static void device_str_attr_destroy(struct attribute *attr)
-{
-	struct dev_ext_attribute *d;
-
-	d = container_of(attr, struct dev_ext_attribute, attr.attr);
-	kfree(d->var);
-	kfree(d->attr.attr.name);
-	kfree(d);
-}
-
 static struct attribute *event_to_attr(unsigned ix,
 				       struct hv_24x7_event_data *event,
 				       unsigned domain,
@@ -387,7 +430,6 @@ static struct attribute *event_to_attr(unsigned ix,
 {
 	int event_name_len;
 	char *ev_name, *a_ev_name, *val;
-	const char *ev_suffix;
 	struct attribute *attr;
 
 	if (!domain_is_valid(domain)) {
@@ -400,14 +442,13 @@ static struct attribute *event_to_attr(unsigned ix,
 	if (!val)
 		return NULL;
 
-	ev_suffix = event_domain_suffix(domain);
 	ev_name = event_name(event, &event_name_len);
 	if (!nonce)
-		a_ev_name = kasprintf(GFP_KERNEL, "%.*s%s",
-				(int)event_name_len, ev_name, ev_suffix);
+		a_ev_name = kasprintf(GFP_KERNEL, "%.*s",
+				(int)event_name_len, ev_name);
 	else
-		a_ev_name = kasprintf(GFP_KERNEL, "%.*s%s__%d",
-				(int)event_name_len, ev_name, ev_suffix, nonce);
+		a_ev_name = kasprintf(GFP_KERNEL, "%.*s__%d",
+				(int)event_name_len, ev_name, nonce);
 
 	if (!a_ev_name)
 		goto out_val;
@@ -452,53 +493,14 @@ event_to_long_desc_attr(struct hv_24x7_event_data *event, int nonce)
 	return device_str_attr_create(name, nl, nonce, desc, dl);
 }
 
-static ssize_t event_data_to_attrs(unsigned ix, struct attribute **attrs,
+static int event_data_to_attrs(unsigned ix, struct attribute **attrs,
 				   struct hv_24x7_event_data *event, int nonce)
 {
-	unsigned i;
-
-	switch (event->domain) {
-	case HV_PERF_DOMAIN_PHYS_CHIP:
-		*attrs = event_to_attr(ix, event, event->domain, nonce);
-		return 1;
-	case HV_PERF_DOMAIN_PHYS_CORE:
-		for (i = 0; i < ARRAY_SIZE(core_domains); i++) {
-			attrs[i] = event_to_attr(ix, event, core_domains[i],
-						nonce);
-			if (!attrs[i]) {
-				pr_warn("catalog event %u: individual attr %u "
-					"creation failure\n", ix, i);
-				for (; i; i--)
-					device_str_attr_destroy(attrs[i - 1]);
-				return -1;
-			}
-		}
-		return i;
-	default:
-		pr_warn("catalog event %u: domain %u is not allowed in the "
-				"catalog\n", ix, event->domain);
+	*attrs = event_to_attr(ix, event, event->domain, nonce);
+	if (!*attrs)
 		return -1;
-	}
-}
 
-static size_t event_to_attr_ct(struct hv_24x7_event_data *event)
-{
-	switch (event->domain) {
-	case HV_PERF_DOMAIN_PHYS_CHIP:
-		return 1;
-	case HV_PERF_DOMAIN_PHYS_CORE:
-		return ARRAY_SIZE(core_domains);
-	default:
-		return 0;
-	}
-}
-
-static unsigned long vmalloc_to_phys(void *v)
-{
-	struct page *p = vmalloc_to_page(v);
-
-	BUG_ON(!p);
-	return page_to_phys(p) + offset_in_page(v);
+	return 0;
 }
 
 /* */
@@ -726,9 +728,8 @@ static int create_events_from_catalog(struct attribute ***events_,
 		goto e_free;
 	}
 
-	if (SIZE_MAX / MAX_EVENTS_PER_EVENT_DATA - 1 < event_entry_count) {
-		pr_err("event_entry_count %zu is invalid\n",
-				event_entry_count);
+	if (SIZE_MAX - 1 < event_entry_count) {
+		pr_err("event_entry_count %zu is invalid\n", event_entry_count);
 		ret = -EIO;
 		goto e_free;
 	}
@@ -801,7 +802,7 @@ static int create_events_from_catalog(struct attribute ***events_,
 			continue;
 		}
 
-		attr_max += event_to_attr_ct(event);
+		attr_max++;
 	}
 
 	event_idx_last = event_idx;
@@ -851,12 +852,12 @@ static int create_events_from_catalog(struct attribute ***events_,
 		nonce = event_uniq_add(&ev_uniq, name, nl, event->domain);
 		ct    = event_data_to_attrs(event_idx, events + event_attr_ct,
 					    event, nonce);
-		if (ct <= 0) {
+		if (ct < 0) {
 			pr_warn("event %zu (%.*s) creation failure, skipping\n",
 				event_idx, nl, name);
 			junk_events++;
 		} else {
-			event_attr_ct += ct;
+			event_attr_ct++;
 			event_descs[desc_ct] = event_to_desc_attr(event, nonce);
 			if (event_descs[desc_ct])
 				desc_ct++;
@@ -961,6 +962,27 @@ e_free:
 	return ret;
 }
 
+static ssize_t domains_show(struct device *dev, struct device_attribute *attr,
+			    char *page)
+{
+	int d, n, count = 0;
+	const char *str;
+
+	for (d = 0; d < HV_PERF_DOMAIN_MAX; d++) {
+		str = domain_name(d);
+		if (!str)
+			continue;
+
+		n = sprintf(page, "%d: %s\n", d, str);
+		if (n < 0)
+			break;
+
+		count += n;
+		page += n;
+	}
+	return count;
+}
+
 #define PAGE_0_ATTR(_name, _fmt, _expr)				\
 static ssize_t _name##_show(struct device *dev,			\
 			    struct device_attribute *dev_attr,	\
@@ -989,6 +1011,7 @@ PAGE_0_ATTR(catalog_version, "%lld\n",
 PAGE_0_ATTR(catalog_len, "%lld\n",
 		(unsigned long long)be32_to_cpu(page_0->length) * 4096);
 static BIN_ATTR_RO(catalog, 0/* real length varies */);
+static DEVICE_ATTR_RO(domains);
 
 static struct bin_attribute *if_bin_attrs[] = {
 	&bin_attr_catalog,
@@ -998,6 +1021,7 @@ static struct bin_attribute *if_bin_attrs[] = {
 static struct attribute *if_attrs[] = {
 	&dev_attr_catalog_len.attr,
 	&dev_attr_catalog_version.attr,
+	&dev_attr_domains.attr,
 	NULL,
 };
 
@@ -1089,10 +1113,16 @@ static int add_event_to_24x7_request(struct perf_event *event,
 		return -EINVAL;
 	}
 
-	if (is_physical_domain(event_get_domain(event)))
+	switch (event_get_domain(event)) {
+	case HV_PERF_DOMAIN_PHYS_CHIP:
+		idx = event_get_chip(event);
+		break;
+	case HV_PERF_DOMAIN_PHYS_CORE:
 		idx = event_get_core(event);
-	else
+		break;
+	default:
 		idx = event_get_vcpu(event);
+	}
 
 	i = request_buffer->num_requests++;
 	req = &request_buffer->requests[i];
@@ -1208,11 +1238,12 @@ static int h_24x7_event_init(struct perf_event *event)
 		return -EACCES;
 	}
 
-	/* see if the event complains */
+	/* Get the initial value of the counter for this event */
 	if (single_24x7_request(event, &ct)) {
 		pr_devel("test hcall failed\n");
 		return -EIO;
 	}
+	(void)local64_xchg(&event->hw.prev_count, ct);
 
 	return 0;
 }
@@ -1275,6 +1306,16 @@ static void h_24x7_event_read(struct perf_event *event)
 			h24x7hw = &get_cpu_var(hv_24x7_hw);
 			h24x7hw->events[i] = event;
 			put_cpu_var(h24x7hw);
+			/*
+			 * Clear the event count so we can compute the _change_
+			 * in the 24x7 raw counter value at the end of the txn.
+			 *
+			 * Note that we could alternatively read the 24x7 value
+			 * now and save its value in event->hw.prev_count. But
+			 * that would require issuing a hcall, which would then
+			 * defeat the purpose of using the txn interface.
+			 */
+			local64_set(&event->count, 0);
 		}
 
 		put_cpu_var(hv_24x7_reqb);