[dpdk-dev] [PATCH 10/16] [RFC] [VFIO] Added support for selecting VFIO interrupt type from EAL command-line

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

Unlike igb_uio, VFIO interrupt type is not set by kernel module
parameters but is set up via ioctl() calls at runtime. This warrants
a new EAL command-line parameter. It will have no effect if VFIO is
not compiled, but will set VFIO interrupt type to either "legacy" or
"msix" if VFIO support is compiled. Note that VFIO initialization will
fail if the interrupt type selected is not supported by the system.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
index d35e0ce..aed37bb 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -99,6 +99,7 @@
 #define OPT_BASE_VIRTADDR   "base-virtaddr"
 #define OPT_XEN_DOM0    "xen-dom0"
 #define OPT_CREATE_UIO_DEV "create-uio-dev"
+#define OPT_VFIO_INTR    "vfio-intr"
 
 #define RTE_EAL_BLACKLIST_SIZE	0x100
 
@@ -363,6 +364,7 @@ eal_usage(const char *prgname)
 	       "  --"OPT_VMWARE_TSC_MAP": use VMware TSC map instead of "
 	    		   "native RDTSC\n"
 	       "  --"OPT_BASE_VIRTADDR": specify base virtual address\n"
+	       "  --"OPT_VFIO_INTR": specify desired interrupt mode for VFIO (intx|msix)\n"
 	       "  --"OPT_CREATE_UIO_DEV": create /dev/uioX (usually done by hotplug)\n"
 	       "\nEAL options for DEBUG use only:\n"
 	       "  --"OPT_NO_HUGE"  : use malloc instead of hugetlbfs\n"
@@ -581,6 +583,27 @@ eal_parse_base_virtaddr(const char *arg)
 	return 0;
 }
 
+static int
+eal_parse_vfio_intr(const char *mode)
+{
+	unsigned i;
+	static struct {
+		const char *name;
+		enum rte_intr_mode value;
+	} map[] = {
+		{ "legacy", RTE_INTR_MODE_LEGACY },
+		{ "msix", RTE_INTR_MODE_MSIX },
+	};
+
+	for (i = 0; i < RTE_DIM(map); i++) {
+		if (!strcmp(mode, map[i].name)) {
+			internal_config.vfio_intr_mode = map[i].value;
+			return 0;
+		}
+	}
+	return -1;
+}
+
 static inline size_t
 eal_get_hugepage_mem_size(void)
 {
@@ -635,6 +658,7 @@ eal_parse_args(int argc, char **argv)
 		{OPT_PCI_BLACKLIST, 1, 0, 0},
 		{OPT_VDEV, 1, 0, 0},
 		{OPT_SYSLOG, 1, NULL, 0},
+		{OPT_VFIO_INTR, 1, NULL, 0},
 		{OPT_BASE_VIRTADDR, 1, 0, 0},
 		{OPT_XEN_DOM0, 0, 0, 0},
 		{OPT_CREATE_UIO_DEV, 1, NULL, 0},
@@ -830,6 +854,14 @@ eal_parse_args(int argc, char **argv)
 					return -1;
 				}
 			}
+			else if (!strcmp(lgopts[option_index].name, OPT_VFIO_INTR)) {
+				if (eal_parse_vfio_intr(optarg) < 0) {
+					RTE_LOG(ERR, EAL, "invalid parameters for --"
+							OPT_VFIO_INTR "\n");
+					eal_usage(prgname);
+					return -1;
+				}
+			}
 			else if (!strcmp(lgopts[option_index].name, OPT_CREATE_UIO_DEV)) {
 				internal_config.create_uio_dev = 1;
 			}
-- 
1.8.1.4