[dpdk-dev] [PACTH v2 2/2] mlx4: fix shared library dependency

[Nelio Laranjeiro <nelio.laranjeiro@6wind.com>]

librte_pmd_mlx4.so needs to be linked with libiverbs otherwise, the PMD is not
able to open Mellanox devices and the following message is printed by testpmd
at startup "librte_pmd_mlx4: cannot access device, is mlx4_ib loaded?".

Applications dependency on libverbs are moved to be only valid in static mode,
in shared mode, applications do not depend on it anymore,
librte_pmd_mlx4.so keeps this dependency and thus is linked with libverbs.

Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
---
Changelog: don't compiled MLX4 PMD when the DPDK is build in combined shared
library.


 doc/guides/nics/mlx4.rst  | 5 +++++
 drivers/net/Makefile      | 6 +++++-
 drivers/net/mlx4/Makefile | 1 +
 mk/rte.app.mk             | 2 +-
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/doc/guides/nics/mlx4.rst b/doc/guides/nics/mlx4.rst
index c33aa38..840cb65 100644
--- a/doc/guides/nics/mlx4.rst
+++ b/doc/guides/nics/mlx4.rst
@@ -47,6 +47,11 @@ There is also a `section dedicated to this poll mode driver
    be enabled manually by setting ``CONFIG_RTE_LIBRTE_MLX4_PMD=y`` and
    recompiling DPDK.
 
+.. warning::
+
+   ``CONFIG_RTE_BUILD_COMBINE_LIBS`` is not supported (if set, it will not
+   compile this PMD even if ``CONFIG_RTE_LIBRTE_MLX4_PMD`` is set).
+
 Implementation details
 ----------------------
 
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 5ebf963..1725c94 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -40,7 +40,6 @@ DIRS-$(CONFIG_RTE_LIBRTE_ENIC_PMD) += enic
 DIRS-$(CONFIG_RTE_LIBRTE_FM10K_PMD) += fm10k
 DIRS-$(CONFIG_RTE_LIBRTE_I40E_PMD) += i40e
 DIRS-$(CONFIG_RTE_LIBRTE_IXGBE_PMD) += ixgbe
-DIRS-$(CONFIG_RTE_LIBRTE_MLX4_PMD) += mlx4
 DIRS-$(CONFIG_RTE_LIBRTE_MPIPE_PMD) += mpipe
 DIRS-$(CONFIG_RTE_LIBRTE_PMD_NULL) += null
 DIRS-$(CONFIG_RTE_LIBRTE_PMD_PCAP) += pcap
@@ -49,5 +48,10 @@ DIRS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtio
 DIRS-$(CONFIG_RTE_LIBRTE_VMXNET3_PMD) += vmxnet3
 DIRS-$(CONFIG_RTE_LIBRTE_PMD_XENVIRT) += xenvirt
 
+# Drivers not support in combined mode
+ifeq ($(CONFIG_RTE_BUILD_COMBINE_LIBS),n)
+DIRS-$(CONFIG_RTE_LIBRTE_MLX4_PMD) += mlx4
+endif
+
 include $(RTE_SDK)/mk/rte.sharelib.mk
 include $(RTE_SDK)/mk/rte.subdir.mk
diff --git a/drivers/net/mlx4/Makefile b/drivers/net/mlx4/Makefile
index 14cb53f..d2f5692 100644
--- a/drivers/net/mlx4/Makefile
+++ b/drivers/net/mlx4/Makefile
@@ -50,6 +50,7 @@ CFLAGS += -g
 CFLAGS += -I.
 CFLAGS += -D_XOPEN_SOURCE=600
 CFLAGS += $(WERROR_FLAGS)
+LDLIBS += -libverbs
 
 # A few warnings cannot be avoided in external headers.
 CFLAGS += -Wno-error=cast-qual
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index 97719cb..04af756 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -100,7 +100,6 @@ ifeq ($(CONFIG_RTE_LIBRTE_VHOST_USER),n)
 _LDLIBS-$(CONFIG_RTE_LIBRTE_VHOST)          += -lfuse
 endif
 
-_LDLIBS-$(CONFIG_RTE_LIBRTE_MLX4_PMD)       += -libverbs
 _LDLIBS-$(CONFIG_RTE_LIBRTE_BNX2X_PMD)      += -lz
 
 _LDLIBS-y += --start-group
@@ -140,6 +139,7 @@ _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_RING)       += -lrte_pmd_ring
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_PCAP)       += -lrte_pmd_pcap
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_AF_PACKET)  += -lrte_pmd_af_packet
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_NULL)       += -lrte_pmd_null
+_LDLIBS-$(CONFIG_RTE_LIBRTE_MLX4_PMD)       += -libverbs
 
 endif # ! $(CONFIG_RTE_BUILD_SHARED_LIB)
 
-- 
1.9.1