[dpdk-dev] [PATCH v6 10/22] eal/dev: implement device iteration initialization

Gaetan Rivet gaetan.rivet at 6wind.com
Fri Apr 13 15:22:25 CEST 2018


Parse a device description.
Split this description in their relevant part for each layers.
No dynamic allocation is performed.

Signed-off-by: Gaetan Rivet <gaetan.rivet at 6wind.com>
---
 lib/Makefile                            |   1 +
 lib/librte_eal/bsdapp/eal/Makefile      |   1 +
 lib/librte_eal/common/eal_common_dev.c  | 148 ++++++++++++++++++++++++++++++++
 lib/librte_eal/common/include/rte_dev.h |  24 ++++++
 lib/librte_eal/linuxapp/eal/Makefile    |   1 +
 lib/librte_eal/rte_eal_version.map      |   1 +
 6 files changed, 176 insertions(+)

diff --git a/lib/Makefile b/lib/Makefile
index fc7a55a37..1b17526f7 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -6,6 +6,7 @@ include $(RTE_SDK)/mk/rte.vars.mk
 DIRS-y += librte_compat
 DIRS-$(CONFIG_RTE_LIBRTE_KVARGS) += librte_kvargs
 DIRS-$(CONFIG_RTE_LIBRTE_EAL) += librte_eal
+DEPDIRS-librte_eal := librte_kvargs
 DIRS-$(CONFIG_RTE_LIBRTE_PCI) += librte_pci
 DEPDIRS-librte_pci := librte_eal
 DIRS-$(CONFIG_RTE_LIBRTE_RING) += librte_ring
diff --git a/lib/librte_eal/bsdapp/eal/Makefile b/lib/librte_eal/bsdapp/eal/Makefile
index de0e6d166..35f98448c 100644
--- a/lib/librte_eal/bsdapp/eal/Makefile
+++ b/lib/librte_eal/bsdapp/eal/Makefile
@@ -18,6 +18,7 @@ CFLAGS += $(WERROR_FLAGS) -O3
 LDLIBS += -lexecinfo
 LDLIBS += -lpthread
 LDLIBS += -lgcc_s
+LDLIBS += -lrte_kvargs
 
 EXPORT_MAP := ../../rte_eal_version.map
 
diff --git a/lib/librte_eal/common/eal_common_dev.c b/lib/librte_eal/common/eal_common_dev.c
index 149e9ad72..d8e306926 100644
--- a/lib/librte_eal/common/eal_common_dev.c
+++ b/lib/librte_eal/common/eal_common_dev.c
@@ -10,9 +10,12 @@
 
 #include <rte_compat.h>
 #include <rte_bus.h>
+#include <rte_class.h>
 #include <rte_dev.h>
 #include <rte_devargs.h>
 #include <rte_debug.h>
+#include <rte_errno.h>
+#include <rte_kvargs.h>
 #include <rte_log.h>
 #include <rte_spinlock.h>
 #include <rte_malloc.h>
@@ -368,3 +371,148 @@ dev_callback_process(char *device_name, enum rte_dev_event_type event)
 	}
 	rte_spinlock_unlock(&dev_event_lock);
 }
+
+static size_t
+dev_layer_count(const char *s)
+{
+	size_t i = s ? 1 : 0;
+
+	while (s != NULL && s[0] != '\0') {
+		i += s[0] == '/';
+		s++;
+	}
+	return i;
+}
+
+__rte_experimental
+int
+rte_dev_iterator_init(struct rte_dev_iterator *it,
+		      const char *devstr)
+{
+	struct {
+		const char *key;
+		const char *str;
+		struct rte_kvargs *kvlist;
+	} layers[] = {
+		{ "bus=",    NULL, NULL, },
+		{ "class=",  NULL, NULL, },
+		{ "driver=", NULL, NULL, },
+	};
+	struct rte_kvargs_pair *kv = NULL;
+	struct rte_class *cls = NULL;
+	struct rte_bus *bus = NULL;
+	const char *s = devstr;
+	size_t nblayer;
+	size_t i = 0;
+
+	/* Having both busstr and clsstr NULL is illegal,
+	 * marking this iterator as invalid unless
+	 * everything goes well.
+	 */
+	it->busstr = NULL;
+	it->clsstr = NULL;
+	/* Split each sub-lists. */
+	nblayer = dev_layer_count(devstr);
+	if (nblayer > RTE_DIM(layers)) {
+		RTE_LOG(ERR, EAL, "Invalid query: too many layers (%zu)\n",
+			nblayer);
+		rte_errno = EINVAL;
+		goto get_out;
+	}
+	while (s != NULL) {
+		char *copy;
+		char *end;
+
+		if (strncmp(layers[i].key, s,
+			    strlen(layers[i].key)))
+			goto next_layer;
+		layers[i].str = s;
+		copy = strdup(s);
+		if (copy == NULL) {
+			RTE_LOG(ERR, EAL, "OOM\n");
+			rte_errno = ENOMEM;
+			goto get_out;
+		}
+		end = strchr(copy, '/');
+		end = end ? end : strchr(copy, '\0');
+		end[0] = '\0';
+		layers[i].kvlist = rte_kvargs_parse(copy, NULL);
+		free(copy);
+		if (layers[i].kvlist == NULL) {
+			RTE_LOG(ERR, EAL, "Could not parse %s\n", s);
+			rte_errno = EINVAL;
+			goto get_out;
+		}
+		s = strchr(s, '/');
+		if (s != NULL)
+			s++;
+next_layer:
+		if (i >= RTE_DIM(layers)) {
+			RTE_LOG(ERR, EAL, "Unrecognized layer %s\n", s);
+			rte_errno = EINVAL;
+			goto get_out;
+		}
+		i++;
+	}
+	/* Parse each sub-list. */
+	for (i = 0; i < RTE_DIM(layers); i++) {
+		if (layers[i].kvlist == NULL)
+			continue;
+		kv = &layers[i].kvlist->pairs[0];
+		if (strcmp(kv->key, "bus") == 0) {
+			bus = rte_bus_find_by_name(kv->value);
+			if (bus == NULL) {
+				RTE_LOG(ERR, EAL, "Could not find bus \"%s\"\n",
+					kv->value);
+				rte_errno = EFAULT;
+				goto get_out;
+			}
+		} else if (strcmp(kv->key, "class") == 0) {
+			cls = rte_class_find_by_name(kv->value);
+			if (cls == NULL) {
+				RTE_LOG(ERR, EAL, "Could not find class \"%s\"\n",
+					kv->value);
+				rte_errno = EFAULT;
+				goto get_out;
+			}
+		} else if (strcmp(kv->key, "driver") == 0) {
+			/* Ignore */
+			continue;
+		}
+	}
+	/* The string should have at least
+	 * one layer specified.
+	 */
+	if (bus == NULL && cls == NULL) {
+		RTE_LOG(ERR, EAL,
+			"Either bus or class must be specified.\n");
+		rte_errno = EINVAL;
+		goto get_out;
+	}
+	if (bus != NULL && bus->dev_iterate == NULL) {
+		RTE_LOG(ERR, EAL, "Bus %s not supported\n", bus->name);
+		rte_errno = ENOTSUP;
+		goto get_out;
+	}
+	if (cls != NULL && cls->dev_iterate == NULL) {
+		RTE_LOG(ERR, EAL, "Class %s not supported\n", cls->name);
+		rte_errno = ENOTSUP;
+		goto get_out;
+	}
+	/* Fill iterator fields. */
+	if (bus != NULL)
+		it->busstr = layers[0].str;
+	if (cls != NULL)
+		it->clsstr = layers[1].str;
+	it->devstr = devstr;
+	it->bus = bus;
+	it->cls = cls;
+	it->device = NULL;
+	it->class_device = NULL;
+get_out:
+	for (i = 0; i < RTE_DIM(layers); i++) {
+		if (layers[i].kvlist)
+			rte_kvargs_free(layers[i].kvlist);
+	}
+	return -rte_errno;
+}
diff --git a/lib/librte_eal/common/include/rte_dev.h b/lib/librte_eal/common/include/rte_dev.h
index a789defc3..eb1ad6182 100644
--- a/lib/librte_eal/common/include/rte_dev.h
+++ b/lib/librte_eal/common/include/rte_dev.h
@@ -329,6 +329,30 @@ typedef void *(*rte_dev_iterate_t)(const void *start,
 				   const char *devstr,
 				   const struct rte_dev_iterator *it);
 
+/**
+ * Initializes a device iterator.
+ *
+ * This iterator allows accessing a list of devices matching a criteria.
+ * The device matching is made among all buses and classes currently registered,
+ * filtered by the device description given as parameter.
+ *
+ * This function will not allocate any memory. It is safe to stop the
+ * iteration at any moment and let the iterator go out of context.
+ *
+ * @param it
+ *   Device iterator handle.
+ *
+ * @param str
+ *   Device description string.
+ *
+ * @return
+ *   0 on successful initialization.
+ *   <0 on error.
+ */
+__rte_experimental
+int
+rte_dev_iterator_init(struct rte_dev_iterator *it, const char *str);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index b11f92e03..47fd07323 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -27,6 +27,7 @@ LDLIBS += -lrt
 ifeq ($(CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES),y)
 LDLIBS += -lnuma
 endif
+LDLIBS += -lrte_kvargs
 
 # specific to linuxapp exec-env
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) := eal.c
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index 75121b08d..1a41e9413 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -223,6 +223,7 @@ EXPERIMENTAL {
 	rte_eal_devargs_remove;
 	rte_class_register;
 	rte_class_unregister;
+	rte_dev_iterator_init;
 	rte_eal_hotplug_add;
 	rte_eal_hotplug_remove;
 	rte_eal_mbuf_user_pool_ops;
-- 
2.11.0



More information about the dev mailing list