env: add spdk_pci_for_each_device

This is a safer alternative to spdk_pci_get_first/next_device,
since those APIs do not hold the lock between calls.

Future patches will remove those APIs, and change callers to
use this new API instead.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I71c7e8c1feb9112da8be32a8056b30e105e30463
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/10655
Reviewed-by: Konrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Aleksey Marchuk <alexeymar@mellanox.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot

CHANGELOG.md

@@ -31,6 +31,10 @@ New APIs, `spdk_nvme_ctrlr_disconnect`, `spdk_nvme_ctrlr_reconnect_async`, and
 the existing APIs,`spdk_nvme_ctrlr_reset_async` and `spdk_nvme_ctrlr_reset_poll_async`
 were deprecated.
 
+### env
+
+Added spdk_pci_for_each_device.
+
 ## v21.10
 
 Structure `spdk_nvmf_target_opts` has been extended with new member `discovery_filter` which allows to specify

include/spdk/env.h

@@ -788,6 +788,14 @@ struct spdk_pci_driver *spdk_pci_nvme_get_driver(void);
  */
 int spdk_pci_enumerate(struct spdk_pci_driver *driver, spdk_pci_enum_cb enum_cb, void *enum_ctx);
 
+/**
+ * Call the provided function pointer for every enumerated PCI device.
+ *
+ * \param ctx Context parameter to pass to fn.
+ * \param fn Function to call for each PCI device
+ */
+void spdk_pci_for_each_device(void *ctx, void (*fn)(void *ctx, struct spdk_pci_device *dev));
+
 /**
  * Begin iterating over enumerated PCI device by calling this function to get
  * the first PCI device. If there no PCI devices enumerated, return NULL

lib/env_dpdk/Makefile

@@ -35,7 +35,7 @@ SPDK_ROOT_DIR := $(abspath $(CURDIR)/../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
 SO_VER := 7
-SO_MINOR := 0
+SO_MINOR := 1
 
 CFLAGS += $(ENV_CFLAGS)
 C_SRCS = env.c memory.c pci.c init.c threads.c

lib/env_dpdk/pci.c

@@ -762,6 +762,18 @@ spdk_pci_enumerate(struct spdk_pci_driver *driver,
 	return 0;
 }
 
+void
+spdk_pci_for_each_device(void *ctx, void (*fn)(void *ctx, struct spdk_pci_device *dev))
+{
+	struct spdk_pci_device *dev;
+
+	pthread_mutex_lock(&g_pci_mutex);
+	TAILQ_FOREACH(dev, &g_pci_devices, internal.tailq) {
+		fn(ctx, dev);
+	}
+	pthread_mutex_unlock(&g_pci_mutex);
+}
+
 struct spdk_pci_device *
 spdk_pci_get_first_device(void)
 {

lib/env_dpdk/spdk_env_dpdk.map

@@ -59,6 +59,7 @@
 	spdk_pci_ioat_get_driver;
 	spdk_pci_virtio_get_driver;
 	spdk_pci_enumerate;
+	spdk_pci_for_each_device;
 	spdk_pci_get_first_device;
 	spdk_pci_get_next_device;
 	spdk_pci_device_map_bar;