On Mon, Jul 20, 2020 at 6:48 PM Thomas Monjalon <tho...@monjalon.net> wrote:
>
> 20/07/2020 18:21, Ferruh Yigit:
> > On 7/17/2020 2:49 PM, Parav Pandit wrote:
> > > Currently mlx5_common uses CLASS priority to initialize
> > > common code before initializing the PMD.
> > > However mlx5_common is not really a class, it is the pre-initialization
> > > code needed for the PMDs.
> > >
> > > In subsequent patch a needed initialization sequence is:
> > > (a) Initialize bus (say pci)
> > > (b) Initialize common code of a driver (mlx5_common)
> > > (c) Register mlx5 class PMDs (mlx5 net, mlx5 vdpa)
> > > Information registered by these PMDs is used by mlx5_bus_pci PMD.
> > > This mlx5 class PMDs should not confused with rte_class.
> > > (d) Register mlx5 PCI bus PMD
> > >
> > > Hence, introduce a new RTE priority level RTE_PRIO_COMMON which
> > > can be used for common initialization and RTE_PRIO_CLASS by mlx5 PMDs
> > > for class driver initialization.
> > >
> > > Signed-off-by: Parav Pandit <pa...@mellanox.com>
> > > Acked-by: Matan Azrad <ma...@mellanox.com>
> > > ---
> > > Changelog:
> > > v2->v3:
> > > - new patch
> > > ---
> > > lib/librte_eal/include/rte_common.h | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/lib/librte_eal/include/rte_common.h
> > > b/lib/librte_eal/include/rte_common.h
> > > index 8f487a563..522afe58e 100644
> > > --- a/lib/librte_eal/include/rte_common.h
> > > +++ b/lib/librte_eal/include/rte_common.h
> > > @@ -135,6 +135,7 @@ typedef uint16_t unaligned_uint16_t;
> > >
> > > #define RTE_PRIORITY_LOG 101
> > > #define RTE_PRIORITY_BUS 110
> > > +#define RTE_PRIORITY_COMMON 119
> > > #define RTE_PRIORITY_CLASS 120
> > > #define RTE_PRIORITY_LAST 65535
> > >
> > >
> >
> > I guess the name "common" selected because of the intention to use it by the
> > common piece of the driver, but only from eal perspective the name
> > "PRIORITY_COMMON" looks so vague, it doesn't describe any purpose.
>
> You're right.
>
> > Also the value doesn't leave any gap between the class priority, what else
> > can
> > be needed in the future in between, right?
>
> And we can imagine a bus requiring a common lib
> to be initialized before.
>
> > @Thomas, @David, I am reluctant to get this eal change through the
> > next-net, can
> > you please review/ack it first?
>
> What about skipping this patch and using "RTE_PRIORITY_CLASS - 1"
> in the code?
net and vdpa code expect the common code being initialised.
It is a dependency internal to mlx5 drivers, I see nothing generic.
The common driver can provide a init function called by net and vdpa
drivers in constructor context (not that I like calling complex init,
but it should be equivalent to current state).
It expresses a clear dependency and there is no constructor semantic
to invent, nor runtime breakage possible because someone tweaks the
priority order in the future.
There is also some hack about a haswell/broadwell detection in LOG
priority that makes no sense.
I compile-tested following:
$ git diff next-net-mlx/master -- lib/librte_eal/ drivers/*/mlx5/
diff --git a/drivers/common/mlx5/mlx5_common.c
b/drivers/common/mlx5/mlx5_common.c
index 79cd5ba344..3fb9a8ab89 100644
--- a/drivers/common/mlx5/mlx5_common.c
+++ b/drivers/common/mlx5/mlx5_common.c
@@ -49,14 +49,6 @@ RTE_INIT_PRIO(mlx5_log_init, LOG)
rte_log_set_level(mlx5_common_logtype, RTE_LOG_NOTICE);
}
-/**
- * Initialization routine for run-time dependency on glue library.
- */
-RTE_INIT_PRIO(mlx5_glue_init, COMMON)
-{
- mlx5_glue_constructor();
-}
-
/**
* This function is responsible of initializing the variable
* haswell_broadwell_cpu by checking if the cpu is intel
@@ -67,7 +59,7 @@ RTE_INIT_PRIO(mlx5_glue_init, COMMON)
* if the cpu is haswell or broadwell the variable will be set to 1
* otherwise it will be 0.
*/
-RTE_INIT_PRIO(mlx5_is_haswell_broadwell_cpu, LOG)
+static void mlx5_is_haswell_broadwell_cpu(void)
{
#ifdef RTE_ARCH_X86_64
unsigned int broadwell_models[4] = {0x3d, 0x47, 0x4F, 0x56};
@@ -114,6 +106,21 @@ RTE_INIT_PRIO(mlx5_is_haswell_broadwell_cpu, LOG)
haswell_broadwell_cpu = 0;
}
+/**
+ * Initialization routine for run-time dependency on glue library.
+ */
+void mlx5_common_init(void)
+{
+ static bool init_once = false;
+
+ if (init_once)
+ return;
+
+ mlx5_glue_constructor();
+ mlx5_is_haswell_broadwell_cpu();
+ init_once = true;
+}
+
/**
* Allocate page of door-bells and register it using DevX API.
*
diff --git a/drivers/common/mlx5/mlx5_common.h
b/drivers/common/mlx5/mlx5_common.h
index 5b9b7bd5a9..30961bc8cc 100644
--- a/drivers/common/mlx5/mlx5_common.h
+++ b/drivers/common/mlx5/mlx5_common.h
@@ -254,6 +254,10 @@ int64_t mlx5_get_dbr(void *ctx, struct
mlx5_dbr_page_list *head,
__rte_internal
int32_t mlx5_release_dbr(struct mlx5_dbr_page_list *head, uint32_t umem_id,
uint64_t offset);
+
+__rte_internal
+void mlx5_common_init(void);
+
extern uint8_t haswell_broadwell_cpu;
#endif /* RTE_PMD_MLX5_COMMON_H_ */
diff --git a/drivers/common/mlx5/rte_common_mlx5_version.map
b/drivers/common/mlx5/rte_common_mlx5_version.map
index fe62fa2b2f..039d221333 100644
--- a/drivers/common/mlx5/rte_common_mlx5_version.map
+++ b/drivers/common/mlx5/rte_common_mlx5_version.map
@@ -1,6 +1,7 @@
INTERNAL {
global:
+ mlx5_common_init;
mlx5_common_verbs_reg_mr;
mlx5_common_verbs_dereg_mr;
diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 846398dd3d..d0e9345a55 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -1989,6 +1989,8 @@ RTE_LOG_REGISTER(mlx5_logtype, pmd.net.mlx5, NOTICE)
*/
RTE_INIT_PRIO(rte_mlx5_pmd_init, CLASS)
{
+ mlx5_common_init();
+
/* Build the static tables for Verbs conversion. */
mlx5_set_ptype_table();
mlx5_set_cksum_table();
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.c b/drivers/vdpa/mlx5/mlx5_vdpa.c
index 70692ea1d2..9dc3e8fa56 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa.c
@@ -844,6 +844,8 @@ RTE_LOG_REGISTER(mlx5_vdpa_logtype, pmd.vdpa.mlx5, NOTICE)
*/
RTE_INIT_PRIO(rte_mlx5_vdpa_init, CLASS)
{
+ mlx5_common_init();
+
if (mlx5_glue)
rte_mlx5_pci_driver_register(&mlx5_vdpa_driver);
}
diff --git a/lib/librte_eal/include/rte_common.h
b/lib/librte_eal/include/rte_common.h
index 522afe58ed..8f487a563d 100644
--- a/lib/librte_eal/include/rte_common.h
+++ b/lib/librte_eal/include/rte_common.h
@@ -135,7 +135,6 @@ typedef uint16_t unaligned_uint16_t;
#define RTE_PRIORITY_LOG 101
#define RTE_PRIORITY_BUS 110
-#define RTE_PRIORITY_COMMON 119
#define RTE_PRIORITY_CLASS 120
#define RTE_PRIORITY_LAST 65535
--
David Marchand
