mlx4_core: scale_profile should work without params set to 0

The "scale_profile" parameter is to be used to do scaling of
hca params without requiring specific tuning setting for each
one of them individually and yet allowing manual setting of
variables.

In UEK2, the module params were default zero and initialized
later from a "driver default" or a scale_profile dictated value.

In UEK4 (derived from Mellanox OFED 2.4) module params were
pre-initialized to default values and are not zero and have
to be forced to 0 for dynamic scaling to be activated.
This defeats the purpose of having a single parameter to achieve
scaling and not requiring setting individual parameters (while
retaining ability to revert to driver defaults).

The changes here (re)introduce a separate static instance
containing default parameters separate from module parameters
which are pre-initialized to zero for parameters that can scale
dynamically and to default values for others. The zero module
parameters are later initialized to either a scale_profile
governed value or driver defaults.

Orabug: 23078816

Signed-off-by: Mukesh Kacker <mukesh.kacker@oracle.com>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index f7176894c46e4641767f9907b1d9c0bde343e169..de4acf2376dd5a2f9bd4886ae8235b57c5550975 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -181,7 +181,8 @@ static atomic_t pf_loading = ATOMIC_INIT(0);
      see mlx4_buddy_init -> bitmap_zero which gets int.
 */
 #define MLX4_MAX_LOG_NUM_MTT 30
-static struct mlx4_profile mod_param_profile = {
+
+static struct mlx4_profile default_profile = {
        .num_qp         = 19,
        .num_srq        = 16,
        .rdmarc_per_qp  = 7,
@@ -191,34 +192,39 @@ static struct mlx4_profile mod_param_profile = {
        .num_mtt_segs   = 0, /* max(20, 2*MTTs for host memory)) */
 };
 
+static struct mlx4_profile mod_param_profile = {
+       .num_qp         = 0,    /* 0=>scale_profile or default 19 */
+       .num_srq        = 0,    /* 0=>scale_profile or default 16 */
+       .rdmarc_per_qp  = 4,
+       .num_cq         = 0,    /* 0=>scale_profile or default 16 */
+       .num_mcg        = 13,
+       .num_mpt        = 19,
+       .num_mtt_segs   = 0, /* max(20, 2*MTTs for host memory)) */
+};
+
 module_param_named(log_num_qp, mod_param_profile.num_qp, int, 0444);
-MODULE_PARM_DESC(log_num_qp, "log maximum number of QPs per HCA (default: 19)");
+MODULE_PARM_DESC(log_num_qp, "log maximum number of QPs per HCA (scale_profile determined value or default: 19)");
 
 module_param_named(log_num_srq, mod_param_profile.num_srq, int, 0444);
-MODULE_PARM_DESC(log_num_srq, "log maximum number of SRQs per HCA "
-                "(default: 16)");
+MODULE_PARM_DESC(log_num_srq, "log maximum number of SRQs per HCA (scale_profile determined value or default: 16)");
 
 module_param_named(log_rdmarc_per_qp, mod_param_profile.rdmarc_per_qp, int,
                   0444);
-MODULE_PARM_DESC(log_rdmarc_per_qp, "log number of RDMARC buffers per QP "
-                "(default: 4)");
+MODULE_PARM_DESC(log_rdmarc_per_qp, "log number of RDMARC buffers per QP (default: 4)");
 
 module_param_named(log_num_cq, mod_param_profile.num_cq, int, 0444);
-MODULE_PARM_DESC(log_num_cq, "log maximum number of CQs per HCA (default: 16)");
+MODULE_PARM_DESC(log_num_cq, "log maximum number of CQs per HCA (scale_profile determined value or default: 16)");
 
 module_param_named(log_num_mcg, mod_param_profile.num_mcg, int, 0444);
-MODULE_PARM_DESC(log_num_mcg, "log maximum number of multicast groups per HCA "
-                "(default: 13)");
+MODULE_PARM_DESC(log_num_mcg, "log maximum number of multicast groups per HCA (default: 13)");
 
 module_param_named(log_num_mpt, mod_param_profile.num_mpt, int, 0444);
 MODULE_PARM_DESC(log_num_mpt,
-                "log maximum number of memory protection table entries per "
-                "HCA (default: 19)");
+                "log maximum number of memory protection table entries per HCA (default: 19)");
 
 module_param_named(log_num_mtt, mod_param_profile.num_mtt_segs, int, 0444);
 MODULE_PARM_DESC(log_num_mtt,
-                "log maximum number of memory translation table segments per "
-                "HCA (default: max(20, 2*MTTs for register all of the host memory limited to 30))");
+                "log maximum number of memory translation table segments per HCA (default: max(20, 2*MTTs for register all of the host memory limited to 30))");
 
 enum {
        MLX4_IF_STATE_BASIC,
@@ -234,52 +240,74 @@ static void process_mod_param_profile(struct mlx4_profile *profile)
                        pr_warn("mlx4_core: Both scale_profile and log_num_qp are set. Ignore scale_profile.\n");
                profile->num_qp = 1 << mod_param_profile.num_qp;
        } else {
-               /* Note: This could be set dynamically based on system/HCA
-                * resources in future. A constant for now.
-                */
-               profile->num_qp = 1 << MLX4_SCALE_LOG_NUM_QP;
-               if (mlx4_scale_profile)
+               if (mlx4_scale_profile) {
+                       /* Note: This could be set dynamically based on
+                        * system/HCA resources in future. A constant for now.
+                        */
+                       profile->num_qp = 1 << MLX4_SCALE_LOG_NUM_QP;
                        pr_info("mlx4_core: Scalable default profile parameters are enabled. Effective log_num_qp is now set to %d.\n",
                                MLX4_SCALE_LOG_NUM_QP);
-               else
-                       pr_info("mlx4_core: log_num_qp not set and scaled dynamically. Effective log_num_qp is now set to %d.\n",
-                               MLX4_SCALE_LOG_NUM_QP);
+                       /* set in mod_param also for sysfs viewing */
+                       mod_param_profile.num_qp = MLX4_SCALE_LOG_NUM_QP;
+               } else {
+                       profile->num_qp = 1 << default_profile.num_qp;
+                       pr_info("mlx4_core: log_num_qp not set and using driver default. Effective profile log_num_qp is now set to %d.\n",
+                               default_profile.num_qp);
+                       /* set in mod_param also for sysfs viewing */
+                       mod_param_profile.num_qp = default_profile.num_qp;
+               }
        }
+
        if (mod_param_profile.num_srq) {
                if (mlx4_scale_profile)
                        pr_warn("mlx4_core: Both scale_profile and log_num_srq are set. Ignore scale_profile.\n");
                profile->num_srq = 1 << mod_param_profile.num_srq;
        } else {
-               /* Note: This could be set dynamically based on system/HCA
-                * resources in future. A constant for now.
-                */
-               profile->num_srq = 1 << MLX4_SCALE_LOG_NUM_SRQ;
-               if (mlx4_scale_profile)
+               if (mlx4_scale_profile) {
+                       /* Note: This could be set dynamically based on
+                        * system/HCA resources in future. A constant for now.
+                        */
+                       profile->num_srq = 1 << MLX4_SCALE_LOG_NUM_SRQ;
                        pr_info("mlx4_core: Scalable default profile parameters are enabled. Effective log_num_srq is now set to %d.\n",
                                MLX4_SCALE_LOG_NUM_SRQ);
-               else
-                       pr_info("mlx4_core: log_num_srq not set and scaled dynamically. Effective log_num_srq is now set to %d.\n",
-                               MLX4_SCALE_LOG_NUM_SRQ);
+                       /* set in mod_param also for sysfs viewing */
+                       mod_param_profile.num_srq = MLX4_SCALE_LOG_NUM_SRQ;
+               } else {
+                       profile->num_srq = 1 << default_profile.num_srq;
+                       pr_info("mlx4_core: log_num_srq not set and using driver default. Effective log_num_srq is now set to %d.\n",
+                               default_profile.num_srq);
+                       /* set in mod_param also for sysfs viewing */
+                       mod_param_profile.num_srq = default_profile.num_srq;
+               }
        }
+
        profile->rdmarc_per_qp = 1 << mod_param_profile.rdmarc_per_qp;
+
        if (mod_param_profile.num_cq) {
                if (mlx4_scale_profile)
                        pr_warn("mlx4_core: Both scale_profile and log_num_cq are set. Ignore scale_profile.\n");
                profile->num_cq = 1 << mod_param_profile.num_cq;
        } else {
-               /* Note: This could be set dynamically based on system/HCA
-                * resources in future. A constant for now.
-                */
-               profile->num_cq = 1 << MLX4_SCALE_LOG_NUM_CQ;
-               if (mlx4_scale_profile)
+               if (mlx4_scale_profile) {
+                       /* Note: This could be set dynamically based on
+                        * system/HCA resources in future. A constant for now.
+                        */
+                       profile->num_cq = 1 << MLX4_SCALE_LOG_NUM_CQ;
                        pr_info("mlx4_core: Scalable default profile parameters are enabled. Effective log_num_cq is now set to %d.\n",
                                MLX4_SCALE_LOG_NUM_CQ);
-               else
-                       pr_info("mlx4_core: log_num_cq not set and scaled dynamically. Effective log_num_cq is now set to %d.\n",
-                               MLX4_SCALE_LOG_NUM_CQ);
+                       /* set in mod_param also for sysfs viewing */
+                       mod_param_profile.num_cq = MLX4_SCALE_LOG_NUM_CQ;
+               } else {
+                       profile->num_cq = 1 << default_profile.num_cq;
+                       pr_info("mlx4_core: log_num_cq not set and using driver default. Effective log_num_cq is now set to %d.\n",
+                               default_profile.num_cq);
+                       /* set in mod_param also for sysfs viewing */
+                       mod_param_profile.num_cq = default_profile.num_cq;
+               }
        }
-       profile->num_mcg       = 1 << mod_param_profile.num_mcg;
-       profile->num_mpt       = 1 << mod_param_profile.num_mpt;
+
+       profile->num_mcg = 1 << mod_param_profile.num_mcg;
+       profile->num_mpt = 1 << mod_param_profile.num_mpt;
 
        /* We want to scale the number of MTTs with the size of the
         * system memory, since it makes sense to register a lot of