Merge branch 'mlxsw-devlink-shared-buffers'

Jiri Pirko says:

====================
devlink + mlxsw: add support for config and control of shared buffers

ASICs implement shared buffer for packet forwarding purposes and enable
flexible partitioning of the shared buffer for different flows and ports,
enabling non-blocking progress of different flows as well as separation
of lossy traffic from loss-less traffic when using Per-Priority Flow
Control (PFC). The shared buffer optimizes the buffer utilization for better
absorption of packet bursts.

This patchset implements API which is based on the model SAI uses. That is
aligned with multiple ASIC vendors so this API should be vendor neutral.

Userspace counterpart patchset for devlink iproute2 tool can be found here:
https://github.com/jpirko/iproute2_mlxsw/tree/devlink_sb

Couple of examples of usage:

switch$ devlink sb help
Usage: devlink sb show [ DEV [ sb SB_INDEX ] ]
       devlink sb pool show [ DEV [ sb SB_INDEX ] pool POOL_INDEX ]
       devlink sb pool set DEV [ sb SB_INDEX ] pool POOL_INDEX
                           size POOL_SIZE thtype { static | dynamic }
       devlink sb port pool show [ DEV/PORT_INDEX [ sb SB_INDEX ]
                                   pool POOL_INDEX ]
       devlink sb port pool set DEV/PORT_INDEX [ sb SB_INDEX ]
                                pool POOL_INDEX th THRESHOLD
       devlink sb tc bind show [ DEV/PORT_INDEX [ sb SB_INDEX ] tc TC_INDEX ]
       devlink sb tc bind set DEV/PORT_INDEX [ sb SB_INDEX ] tc TC_INDEX
                              type { ingress | egress } pool POOL_INDEX
                              th THRESHOLD
       devlink sb occupancy show { DEV | DEV/PORT_INDEX } [ sb SB_INDEX ]
       devlink sb occupancy snapshot DEV [ sb SB_INDEX ]
       devlink sb occupancy clearmax DEV [ sb SB_INDEX ]

switch$ devlink sb show
pci/0000:03:00.0: sb 0 size 16777216 ing_pools 4 eg_pools 4 ing_tcs 8 eg_tcs 8

switch$ devlink sb pool show
pci/0000:03:00.0: sb 0 pool 0 type ingress size 12400032 thtype dynamic
pci/0000:03:00.0: sb 0 pool 1 type ingress size 0 thtype dynamic
pci/0000:03:00.0: sb 0 pool 2 type ingress size 0 thtype dynamic
pci/0000:03:00.0: sb 0 pool 3 type ingress size 200064 thtype dynamic
pci/0000:03:00.0: sb 0 pool 4 type egress size 13220064 thtype dynamic
pci/0000:03:00.0: sb 0 pool 5 type egress size 0 thtype dynamic
pci/0000:03:00.0: sb 0 pool 6 type egress size 0 thtype dynamic
pci/0000:03:00.0: sb 0 pool 7 type egress size 0 thtype dynamic

switch$ devlink sb port pool show sw0p7 pool 0
sw0p7: sb 0 pool 0 threshold 16

switch$ sudo devlink sb port pool set sw0p7 pool 0 th 15

switch$ devlink sb port pool show sw0p7 pool 0
sw0p7: sb 0 pool 0 threshold 15

switch$ devlink sb tc bind show sw0p7 tc 0 type ingress
sw0p7: sb 0 tc 0 type ingress pool 0 threshold 10

switch$ sudo devlink sb tc bind set sw0p7 tc 0 type ingress pool 0 th 9

switch$ devlink sb tc bind show sw0p7 tc 0 type ingress
sw0p7: sb 0 tc 0 type ingress pool 0 threshold 9

switch$ sudo devlink sb occupancy snapshot pci/0000:03:00.0

switch$ devlink sb occupancy show sw0p7
sw0p7:
  pool: 0:      82944/3217344 1:          0/0       2:          0/0       3:          0/0
        4:          0/384     5:          0/0       6:          0/0       7:          0/0
  itc:  0(0):   96768/3217344 1(0):       0/0       2(0):       0/0       3(0):       0/0
        4(0):       0/0       5(0):       0/0       6(0):       0/0       7(0):       0/0
  etc:  0(4):       0/384     1(4):       0/0       2(4):       0/0       3(4):       0/0
        4(4):       0/0       5(4):       0/0       6(4):       0/0       7(4):       0/0

switch$ sudo devlink sb occupancy clearmax pci/0000:03:00.0
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 63 insertions, 0 deletions

diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index c9fee5781eb1..ba0073b26fa6 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -33,6 +33,30 @@ enum devlink_command {
 	DEVLINK_CMD_PORT_SPLIT,
 	DEVLINK_CMD_PORT_UNSPLIT,
 
+	DEVLINK_CMD_SB_GET,		/* can dump */
+	DEVLINK_CMD_SB_SET,
+	DEVLINK_CMD_SB_NEW,
+	DEVLINK_CMD_SB_DEL,
+
+	DEVLINK_CMD_SB_POOL_GET,	/* can dump */
+	DEVLINK_CMD_SB_POOL_SET,
+	DEVLINK_CMD_SB_POOL_NEW,
+	DEVLINK_CMD_SB_POOL_DEL,
+
+	DEVLINK_CMD_SB_PORT_POOL_GET,	/* can dump */
+	DEVLINK_CMD_SB_PORT_POOL_SET,
+	DEVLINK_CMD_SB_PORT_POOL_NEW,
+	DEVLINK_CMD_SB_PORT_POOL_DEL,
+
+	DEVLINK_CMD_SB_TC_POOL_BIND_GET,	/* can dump */
+	DEVLINK_CMD_SB_TC_POOL_BIND_SET,
+	DEVLINK_CMD_SB_TC_POOL_BIND_NEW,
+	DEVLINK_CMD_SB_TC_POOL_BIND_DEL,
+
+	/* Shared buffer occupancy monitoring commands */
+	DEVLINK_CMD_SB_OCC_SNAPSHOT,
+	DEVLINK_CMD_SB_OCC_MAX_CLEAR,
+
 	/* add new commands above here */
 
 	__DEVLINK_CMD_MAX,
@@ -46,6 +70,31 @@ enum devlink_port_type {
 	DEVLINK_PORT_TYPE_IB,
 };
 
+enum devlink_sb_pool_type {
+	DEVLINK_SB_POOL_TYPE_INGRESS,
+	DEVLINK_SB_POOL_TYPE_EGRESS,
+};
+
+/* static threshold - limiting the maximum number of bytes.
+ * dynamic threshold - limiting the maximum number of bytes
+ *   based on the currently available free space in the shared buffer pool.
+ *   In this mode, the maximum quota is calculated based
+ *   on the following formula:
+ *     max_quota = alpha / (1 + alpha) * Free_Buffer
+ *   While Free_Buffer is the amount of none-occupied buffer associated to
+ *   the relevant pool.
+ *   The value range which can be passed is 0-20 and serves
+ *   for computation of alpha by following formula:
+ *     alpha = 2 ^ (passed_value - 10)
+ */
+
+enum devlink_sb_threshold_type {
+	DEVLINK_SB_THRESHOLD_TYPE_STATIC,
+	DEVLINK_SB_THRESHOLD_TYPE_DYNAMIC,
+};
+
+#define DEVLINK_SB_THRESHOLD_TO_ALPHA_MAX 20
+
 enum devlink_attr {
 	/* don't change the order or add anything between, this is ABI! */
 	DEVLINK_ATTR_UNSPEC,
@@ -62,6 +111,20 @@ enum devlink_attr {
 	DEVLINK_ATTR_PORT_IBDEV_NAME,		/* string */
 	DEVLINK_ATTR_PORT_SPLIT_COUNT,		/* u32 */
 	DEVLINK_ATTR_PORT_SPLIT_GROUP,		/* u32 */
+	DEVLINK_ATTR_SB_INDEX,			/* u32 */
+	DEVLINK_ATTR_SB_SIZE,			/* u32 */
+	DEVLINK_ATTR_SB_INGRESS_POOL_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_EGRESS_POOL_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_INGRESS_TC_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_EGRESS_TC_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_POOL_INDEX,		/* u16 */
+	DEVLINK_ATTR_SB_POOL_TYPE,		/* u8 */
+	DEVLINK_ATTR_SB_POOL_SIZE,		/* u32 */
+	DEVLINK_ATTR_SB_POOL_THRESHOLD_TYPE,	/* u8 */
+	DEVLINK_ATTR_SB_THRESHOLD,		/* u32 */
+	DEVLINK_ATTR_SB_TC_INDEX,		/* u16 */
+	DEVLINK_ATTR_SB_OCC_CUR,		/* u32 */
+	DEVLINK_ATTR_SB_OCC_MAX,		/* u32 */
 
 	/* add new attributes above here, update the policy in devlink.c */