Re: [dpdk-dev] [PATCH v2 02/16] Distinguish between legitimate failures and non-fatal errors

["Xu, HuilongX" <huilongx.xu@intel.com>]

Currently, EAL does not distinguish between actual failures and
expected initialization errors. E.g. sometimes the driver fails to
initialize because it was not supposed to be initialized in the
first place, such as device not being managed by said driver.

This patch makes EAL fail on actual initialization errors while
still skipping over expected initialization errors.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Test-by: HuilongX Xu <huilongx.xu@intel.com>
Compile pass
     >>Compile OS: FC20 x86_64
     >>Kernel version: 3.13.6-200
     >>GCC version: 4.8.2
     >>Server: Crownpass
---
lib/librte_eal/common/eal_common_pci.c    |   16 +++++++++-------
lib/librte_eal/linuxapp/eal/eal_pci.c     |    7 ++++---
lib/librte_eal/linuxapp/eal/eal_pci_uio.c |    4 ++--
3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_pci.c b/lib/librte_eal/common/eal_common_pci.c
index 7c23e86..1fb8f2c 100644
--- a/lib/librte_eal/common/eal_common_pci.c
+++ b/lib/librte_eal/common/eal_common_pci.c
@@ -101,8 +101,8 @@ static struct rte_devargs *pci_devargs_lookup(struct rte_pci_device *dev)
 /*
  * If vendor/device ID match, call the devinit() function of all
- * registered driver for the given device. Return -1 if no driver is
- * found for this device.
+ * registered driver for the given device. Return -1 if initialization
+ * failed, return 1 if no driver is found for this device.
  * For drivers with the RTE_PCI_DRV_MULTIPLE flag enabled, register
  * the same device multiple times until failure to do so.
  * It is required for non-Intel NIC drivers provided by third-parties such
@@ -118,7 +118,7 @@ pci_probe_all_drivers(struct rte_pci_device *dev)
                               rc = rte_eal_pci_probe_one_driver(dr, dev);
                               if (rc < 0)
                                               /* negative value is an error */
-                                              break;
+                                             return -1;
                               if (rc > 0)
                                               /* positive value means driver not found */
                                               continue;
@@ -130,7 +130,7 @@ pci_probe_all_drivers(struct rte_pci_device *dev)
                                                               ;
                               return 0;
               }
-              return -1;
+             return 1;
}
 /*
@@ -144,6 +144,7 @@ rte_eal_pci_probe(void)
               struct rte_pci_device *dev = NULL;
               struct rte_devargs *devargs;
               int probe_all = 0;
+             int ret = 0;
                if (rte_eal_devargs_type_count(RTE_DEVTYPE_WHITELISTED_PCI) == 0)
                               probe_all = 1;
@@ -157,10 +158,11 @@ rte_eal_pci_probe(void)
                                /* probe all or only whitelisted devices */
                               if (probe_all)
-                                              pci_probe_all_drivers(dev);
+                                             ret = pci_probe_all_drivers(dev);
                               else if (devargs != NULL &&
-                                              devargs->type == RTE_DEVTYPE_WHITELISTED_PCI &&
-                                              pci_probe_all_drivers(dev) < 0)
+                                             devargs->type == RTE_DEVTYPE_WHITELISTED_PCI)
+                                             ret = pci_probe_all_drivers(dev);
+                             if (ret < 0)
                                               rte_exit(EXIT_FAILURE, "Requested device " PCI_PRI_FMT
                                                                " cannot be used\n", dev->addr.domain, dev->addr.bus,
                                                                dev->addr.devid, dev->addr.function);
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index cd5b797..de1b0a0 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -400,6 +400,7 @@ int
rte_eal_pci_probe_one_driver(struct rte_pci_driver *dr, struct rte_pci_device *dev)
{
               struct rte_pci_id *id_table;
+             int ret = 0;
                for (id_table = dr->id_table ; id_table->vendor_id != 0; id_table++) {
@@ -430,13 +431,13 @@ rte_eal_pci_probe_one_driver(struct rte_pci_driver *dr, struct rte_pci_device *d
                               if (dev->devargs != NULL &&
                                               dev->devargs->type == RTE_DEVTYPE_BLACKLISTED_PCI) {
                                               RTE_LOG(DEBUG, EAL, "  Device is blacklisted, not initializing\n");
-                                              return 0;
+                                             return 1;
                               }
                                if (dr->drv_flags & RTE_PCI_DRV_NEED_IGB_UIO) {
                                               /* map resources for devices that use igb_uio */
-                                              if (pci_uio_map_resource(dev) < 0)
-                                                              return -1;
+                                             if ((ret = pci_uio_map_resource(dev)) != 0)
+                                                             return ret;
                               } else if (dr->drv_flags & RTE_PCI_DRV_FORCE_UNBIND &&
                                          rte_eal_process_type() == RTE_PROC_PRIMARY) {
                                               /* unbind current driver */
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
index f29fee5..2d5e75d 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
@@ -137,7 +137,7 @@ pci_uio_map_secondary(struct rte_pci_device *dev) {
               }
                RTE_LOG(ERR, EAL, "Cannot find resource for device\n");
-              return -1;
+             return 1;
}
 static int
@@ -284,7 +284,7 @@ pci_uio_map_resource(struct rte_pci_device *dev) {
               if (uio_num < 0) {
                               RTE_LOG(WARNING, EAL, "  "PCI_PRI_FMT" not managed by UIO driver, "
                               "skipping\n", loc->domain, loc->bus, loc->devid, loc->function);
-                              return -1;
+                             return 1;
               }
               rte_snprintf(devname, sizeof(devname), "/dev/uio%u", uio_num);
--
1.7.0.7