net/mlx5: HWS, added memory management handling

Added object pools and buddy allocator functionality.

Reviewed-by: Itamar Gozlan <[email protected]>
Signed-off-by: Yevgeny Kliteynik <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>

Author: kliteyn

drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_buddy.c

@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2024 NVIDIA Corporation & Affiliates */
+
+#include "mlx5hws_internal.h"
+#include "mlx5hws_buddy.h"
+
+static int hws_buddy_init(struct mlx5hws_buddy_mem *buddy, u32 max_order)
+{
+	int i, s, ret = 0;
+
+	buddy->max_order = max_order;
+
+	buddy->bitmap = kcalloc(buddy->max_order + 1,
+				sizeof(*buddy->bitmap),
+				GFP_KERNEL);
+	if (!buddy->bitmap)
+		return -ENOMEM;
+
+	buddy->num_free = kcalloc(buddy->max_order + 1,
+				  sizeof(*buddy->num_free),
+				  GFP_KERNEL);
+	if (!buddy->num_free) {
+		ret = -ENOMEM;
+		goto err_out_free_bits;
+	}
+
+	for (i = 0; i <= (int)buddy->max_order; ++i) {
+		s = 1 << (buddy->max_order - i);
+
+		buddy->bitmap[i] = bitmap_zalloc(s, GFP_KERNEL);
+		if (!buddy->bitmap[i]) {
+			ret = -ENOMEM;
+			goto err_out_free_num_free;
+		}
+	}
+
+	bitmap_set(buddy->bitmap[buddy->max_order], 0, 1);
+	buddy->num_free[buddy->max_order] = 1;
+
+	return 0;
+
+err_out_free_num_free:
+	for (i = 0; i <= (int)buddy->max_order; ++i)
+		bitmap_free(buddy->bitmap[i]);
+
+	kfree(buddy->num_free);
+
+err_out_free_bits:
+	kfree(buddy->bitmap);
+	return ret;
+}
+
+struct mlx5hws_buddy_mem *mlx5hws_buddy_create(u32 max_order)
+{
+	struct mlx5hws_buddy_mem *buddy;
+
+	buddy = kzalloc(sizeof(*buddy), GFP_KERNEL);
+	if (!buddy)
+		return NULL;
+
+	if (hws_buddy_init(buddy, max_order))
+		goto free_buddy;
+
+	return buddy;
+
+free_buddy:
+	kfree(buddy);
+	return NULL;
+}
+
+void mlx5hws_buddy_cleanup(struct mlx5hws_buddy_mem *buddy)
+{
+	int i;
+
+	for (i = 0; i <= (int)buddy->max_order; ++i)
+		bitmap_free(buddy->bitmap[i]);
+
+	kfree(buddy->num_free);
+	kfree(buddy->bitmap);
+}
+
+static int hws_buddy_find_free_seg(struct mlx5hws_buddy_mem *buddy,
+				   u32 start_order,
+				   u32 *segment,
+				   u32 *order)
+{
+	unsigned int seg, order_iter, m;
+
+	for (order_iter = start_order;
+	     order_iter <= buddy->max_order; ++order_iter) {
+		if (!buddy->num_free[order_iter])
+			continue;
+
+		m = 1 << (buddy->max_order - order_iter);
+		seg = find_first_bit(buddy->bitmap[order_iter], m);
+
+		if (WARN(seg >= m,
+			 "ICM Buddy: failed finding free mem for order %d\n",
+			 order_iter))
+			return -ENOMEM;
+
+		break;
+	}
+
+	if (order_iter > buddy->max_order)
+		return -ENOMEM;
+
+	*segment = seg;
+	*order = order_iter;
+	return 0;
+}
+
+int mlx5hws_buddy_alloc_mem(struct mlx5hws_buddy_mem *buddy, u32 order)
+{
+	u32 seg, order_iter, err;
+
+	err = hws_buddy_find_free_seg(buddy, order, &seg, &order_iter);
+	if (err)
+		return err;
+
+	bitmap_clear(buddy->bitmap[order_iter], seg, 1);
+	--buddy->num_free[order_iter];
+
+	while (order_iter > order) {
+		--order_iter;
+		seg <<= 1;
+		bitmap_set(buddy->bitmap[order_iter], seg ^ 1, 1);
+		++buddy->num_free[order_iter];
+	}
+
+	seg <<= order;
+
+	return seg;
+}
+
+void mlx5hws_buddy_free_mem(struct mlx5hws_buddy_mem *buddy, u32 seg, u32 order)
+{
+	seg >>= order;
+
+	while (test_bit(seg ^ 1, buddy->bitmap[order])) {
+		bitmap_clear(buddy->bitmap[order], seg ^ 1, 1);
+		--buddy->num_free[order];
+		seg >>= 1;
+		++order;
+	}
+
+	bitmap_set(buddy->bitmap[order], seg, 1);
+	++buddy->num_free[order];
+}

drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_buddy.h

@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2024 NVIDIA Corporation & Affiliates */
+
+#ifndef MLX5HWS_BUDDY_H_
+#define MLX5HWS_BUDDY_H_
+
+struct mlx5hws_buddy_mem {
+	unsigned long **bitmap;
+	unsigned int *num_free;
+	u32 max_order;
+};
+
+struct mlx5hws_buddy_mem *mlx5hws_buddy_create(u32 max_order);
+
+void mlx5hws_buddy_cleanup(struct mlx5hws_buddy_mem *buddy);
+
+int mlx5hws_buddy_alloc_mem(struct mlx5hws_buddy_mem *buddy, u32 order);
+
+void mlx5hws_buddy_free_mem(struct mlx5hws_buddy_mem *buddy, u32 seg, u32 order);
+
+#endif /* MLX5HWS_BUDDY_H_ */