powerpc/perf/hv-24x7: Support v2 of the hypervisor API

POWER9 introduces a new version of the hypervisor API to access the 24x7
perf counters. The new version changed some of the structures used for
requests and results.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 49 insertions, 9 deletions

diff --git a/arch/powerpc/perf/hv-24x7.h b/arch/powerpc/perf/hv-24x7.h
index b95909400b2a..5092c4a222a6 100644
--- a/arch/powerpc/perf/hv-24x7.h
+++ b/arch/powerpc/perf/hv-24x7.h
@@ -10,6 +10,8 @@ enum hv_perf_domains {
 	HV_PERF_DOMAIN_MAX,
 };
 
+#define H24x7_REQUEST_SIZE(iface_version)	(iface_version == 1 ? 16 : 32)
+
 struct hv_24x7_request {
 	/* PHYSICAL domains require enabling via phyp/hmc. */
 	__u8 performance_domain;
@@ -42,19 +44,47 @@ struct hv_24x7_request {
 	/* chip, core, or virtual processor based on @performance_domain */
 	__be16 starting_ix;
 	__be16 max_ix;
+
+	/* The following fields were added in v2 of the 24x7 interface. */
+
+	__u8 starting_thread_group_ix;
+
+	/* -1 means all thread groups starting at @starting_thread_group_ix */
+	__u8 max_num_thread_groups;
+
+	__u8 reserved2[0xE];
 } __packed;
 
 struct hv_24x7_request_buffer {
 	/* 0 - ? */
 	/* 1 - ? */
-#define HV_24X7_IF_VERSION_CURRENT 0x01
 	__u8 interface_version;
 	__u8 num_requests;
 	__u8 reserved[0xE];
-	struct hv_24x7_request requests[1];
+	struct hv_24x7_request requests[];
+} __packed;
+
+struct hv_24x7_result_element_v1 {
+	__be16 lpar_ix;
+
+	/*
+	 * represents the core, chip, or virtual processor based on the
+	 * request's @performance_domain
+	 */
+	__be16 domain_ix;
+
+	/* -1 if @performance_domain does not refer to a virtual processor */
+	__be32 lpar_cfg_instance_id;
+
+	/* size = @result_element_data_size of containing result. */
+	__u64 element_data[];
 } __packed;
 
-struct hv_24x7_result_element {
+/*
+ * We need a separate struct for v2 because the offset of @element_data changed
+ * between versions.
+ */
+struct hv_24x7_result_element_v2 {
 	__be16 lpar_ix;
 
 	/*
@@ -66,8 +96,12 @@ struct hv_24x7_result_element {
 	/* -1 if @performance_domain does not refer to a virtual processor */
 	__be32 lpar_cfg_instance_id;
 
+	__u8 thread_group_ix;
+
+	__u8 reserved[7];
+
 	/* size = @result_element_data_size of containing result. */
-	__u64 element_data[1];
+	__u64 element_data[];
 } __packed;
 
 struct hv_24x7_result {
@@ -94,10 +128,16 @@ struct hv_24x7_result {
 	__be16 result_element_data_size;
 	__u8 reserved[0x2];
 
-	/* WARNING: only valid for first result element due to variable sizes
-	 *          of result elements */
-	/* struct hv_24x7_result_element[@num_elements_returned] */
-	struct hv_24x7_result_element elements[1];
+	/*
+	 * Either
+	 *	struct hv_24x7_result_element_v1[@num_elements_returned]
+	 * or
+	 *	struct hv_24x7_result_element_v2[@num_elements_returned]
+	 *
+	 * depending on the interface_version field of the
+	 * struct hv_24x7_data_result_buffer containing this result.
+	 */
+	char elements[];
 } __packed;
 
 struct hv_24x7_data_result_buffer {
@@ -113,7 +153,7 @@ struct hv_24x7_data_result_buffer {
 	__u8 reserved2[0x8];
 	/* WARNING: only valid for the first result due to variable sizes of
 	 *	    results */
-	struct hv_24x7_result results[1]; /* [@num_results] */
+	struct hv_24x7_result results[]; /* [@num_results] */
 } __packed;
 
 #endif