nvme: Directly lookup op code

Rather than have a table to walk through, use a sparse array.

Suggested by:		jhb
Sponsored by:		Netflix
Differential Revision:	https://reviews.freebsd.org/D41353

1 files changed, 55 insertions, 59 deletions

diff --git a/sys/dev/nvme/nvme_qpair.c b/sys/dev/nvme/nvme_qpair.c
index 878df6183eea..9e15749d1bca 100644
--- a/sys/dev/nvme/nvme_qpair.c
+++ b/sys/dev/nvme/nvme_qpair.c
@@ -46,71 +46,67 @@ static void	_nvme_qpair_submit_request(struct nvme_qpair *qpair,
 					   struct nvme_request *req);
 static void	nvme_qpair_destroy(struct nvme_qpair *qpair);
 
-struct nvme_opcode_string {
-	uint16_t	opc;
-	const char *	str;
-};
-
-static struct nvme_opcode_string admin_opcode[] = {
-	{ NVME_OPC_DELETE_IO_SQ, "DELETE IO SQ" },
-	{ NVME_OPC_CREATE_IO_SQ, "CREATE IO SQ" },
-	{ NVME_OPC_GET_LOG_PAGE, "GET LOG PAGE" },
-	{ NVME_OPC_DELETE_IO_CQ, "DELETE IO CQ" },
-	{ NVME_OPC_CREATE_IO_CQ, "CREATE IO CQ" },
-	{ NVME_OPC_IDENTIFY, "IDENTIFY" },
-	{ NVME_OPC_ABORT, "ABORT" },
-	{ NVME_OPC_SET_FEATURES, "SET FEATURES" },
-	{ NVME_OPC_GET_FEATURES, "GET FEATURES" },
-	{ NVME_OPC_ASYNC_EVENT_REQUEST, "ASYNC EVENT REQUEST" },
-	{ NVME_OPC_NAMESPACE_MANAGEMENT, "NAMESPACE MANAGEMENT" },
-	{ NVME_OPC_FIRMWARE_ACTIVATE, "FIRMWARE ACTIVATE" },
-	{ NVME_OPC_FIRMWARE_IMAGE_DOWNLOAD, "FIRMWARE IMAGE DOWNLOAD" },
-	{ NVME_OPC_DEVICE_SELF_TEST, "DEVICE SELF-TEST" },
-	{ NVME_OPC_NAMESPACE_ATTACHMENT, "NAMESPACE ATTACHMENT" },
-	{ NVME_OPC_KEEP_ALIVE, "KEEP ALIVE" },
-	{ NVME_OPC_DIRECTIVE_SEND, "DIRECTIVE SEND" },
-	{ NVME_OPC_DIRECTIVE_RECEIVE, "DIRECTIVE RECEIVE" },
-	{ NVME_OPC_VIRTUALIZATION_MANAGEMENT, "VIRTUALIZATION MANAGEMENT" },
-	{ NVME_OPC_NVME_MI_SEND, "NVME-MI SEND" },
-	{ NVME_OPC_NVME_MI_RECEIVE, "NVME-MI RECEIVE" },
-	{ NVME_OPC_CAPACITY_MANAGEMENT, "CAPACITY MANAGEMENT" },
-	{ NVME_OPC_LOCKDOWN, "LOCKDOWN" },
-	{ NVME_OPC_DOORBELL_BUFFER_CONFIG, "DOORBELL BUFFER CONFIG" },
-	{ NVME_OPC_FABRICS_COMMANDS, "FABRICS COMMANDS" },
-	{ NVME_OPC_FORMAT_NVM, "FORMAT NVM" },
-	{ NVME_OPC_SECURITY_SEND, "SECURITY SEND" },
-	{ NVME_OPC_SECURITY_RECEIVE, "SECURITY RECEIVE" },
-	{ NVME_OPC_SANITIZE, "SANITIZE" },
-	{ NVME_OPC_GET_LBA_STATUS, "GET LBA STATUS" },
-	{ 0xFFFF, "ADMIN COMMAND" }
+#define DEFAULT_INDEX	256
+#define DEFAULT_ENTRY(x)	[DEFAULT_INDEX] = x
+#define OPC_ENTRY(x)		[NVME_OPC_ ## x] = #x
+
+static const char *admin_opcode[DEFAULT_INDEX + 1] = {
+	OPC_ENTRY(DELETE_IO_SQ),
+	OPC_ENTRY(CREATE_IO_SQ),
+	OPC_ENTRY(GET_LOG_PAGE),
+	OPC_ENTRY(DELETE_IO_CQ),
+	OPC_ENTRY(CREATE_IO_CQ),
+	OPC_ENTRY(IDENTIFY),
+	OPC_ENTRY(ABORT),
+	OPC_ENTRY(SET_FEATURES),
+	OPC_ENTRY(GET_FEATURES),
+	OPC_ENTRY(ASYNC_EVENT_REQUEST),
+	OPC_ENTRY(NAMESPACE_MANAGEMENT),
+	OPC_ENTRY(FIRMWARE_ACTIVATE),
+	OPC_ENTRY(FIRMWARE_IMAGE_DOWNLOAD),
+	OPC_ENTRY(DEVICE_SELF_TEST),
+	OPC_ENTRY(NAMESPACE_ATTACHMENT),
+	OPC_ENTRY(KEEP_ALIVE),
+	OPC_ENTRY(DIRECTIVE_SEND),
+	OPC_ENTRY(DIRECTIVE_RECEIVE),
+	OPC_ENTRY(VIRTUALIZATION_MANAGEMENT),
+	OPC_ENTRY(NVME_MI_SEND),
+	OPC_ENTRY(NVME_MI_RECEIVE),
+	OPC_ENTRY(CAPACITY_MANAGEMENT),
+	OPC_ENTRY(LOCKDOWN),
+	OPC_ENTRY(DOORBELL_BUFFER_CONFIG),
+	OPC_ENTRY(FABRICS_COMMANDS),
+	OPC_ENTRY(FORMAT_NVM),
+	OPC_ENTRY(SECURITY_SEND),
+	OPC_ENTRY(SECURITY_RECEIVE),
+	OPC_ENTRY(SANITIZE),
+	OPC_ENTRY(GET_LBA_STATUS),
+	DEFAULT_ENTRY("ADMIN COMMAND"),
 };
 
-static struct nvme_opcode_string io_opcode[] = {
-	{ NVME_OPC_FLUSH, "FLUSH" },
-	{ NVME_OPC_WRITE, "WRITE" },
-	{ NVME_OPC_READ, "READ" },
-	{ NVME_OPC_WRITE_UNCORRECTABLE, "WRITE UNCORRECTABLE" },
-	{ NVME_OPC_COMPARE, "COMPARE" },
-	{ NVME_OPC_WRITE_ZEROES, "WRITE ZEROES" },
-	{ NVME_OPC_DATASET_MANAGEMENT, "DATASET MANAGEMENT" },
-	{ NVME_OPC_VERIFY, "VERIFY" },
-	{ NVME_OPC_RESERVATION_REGISTER, "RESERVATION REGISTER" },
-	{ NVME_OPC_RESERVATION_REPORT, "RESERVATION REPORT" },
-	{ NVME_OPC_RESERVATION_ACQUIRE, "RESERVATION ACQUIRE" },
-	{ NVME_OPC_RESERVATION_RELEASE, "RESERVATION RELEASE" },
-	{ NVME_OPC_COPY, "COPY" },
-	{ 0xFFFF, "IO COMMAND" }
+static const char *io_opcode[DEFAULT_INDEX + 1] = {
+	OPC_ENTRY(FLUSH),
+	OPC_ENTRY(WRITE),
+	OPC_ENTRY(READ),
+	OPC_ENTRY(WRITE_UNCORRECTABLE),
+	OPC_ENTRY(COMPARE),
+	OPC_ENTRY(WRITE_ZEROES),
+	OPC_ENTRY(DATASET_MANAGEMENT),
+	OPC_ENTRY(VERIFY),
+	OPC_ENTRY(RESERVATION_REGISTER),
+	OPC_ENTRY(RESERVATION_REPORT),
+	OPC_ENTRY(RESERVATION_ACQUIRE),
+	OPC_ENTRY(RESERVATION_RELEASE),
+	OPC_ENTRY(COPY),
+	DEFAULT_ENTRY("IO COMMAND"),
 };
 
 static const char *
-get_opcode_string(struct nvme_opcode_string *entry, uint16_t opc)
+get_opcode_string(const char *op[DEFAULT_INDEX + 1], uint16_t opc)
 {
-	while (entry->opc != 0xFFFF) {
-		if (entry->opc == opc)
-			return (entry->str);
-		entry++;
-	}
-	return (entry->str);
+	const char *nm = opc < DEFAULT_INDEX ? op[opc] : op[DEFAULT_INDEX];
+
+	return (nm != NULL ? nm : op[DEFAULT_INDEX]);
 }
 
 static const char *