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authorYijie Yang <yijie.yang@oss.qualcomm.com>2026-08-11 16:46:47 +0800
committerRob Herring (Arm) <robh@kernel.org>2026-08-15 15:46:52 -0500
commite1c13aed4a1641550e8c9518c96f016e1d52d09b (patch)
tree61c2297688373db165cc857b7c7adcb147a5c419 /fs/btrfs/lru_cache.h
downloadlinux-stable-e1c13aed4a1641550e8c9518c96f016e1d52d09b.tar.gz
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dt-bindings: interconnect: qcom-bwmon: Add Maili cpu-bwmon compatiblegrafted
Add the Qualcomm Maili SoC compatible string for the CPU bandwidth monitor (BWMONv4). This falls back to the sdm845-bwmon compatible, consistent with the existing pattern used by other recent SoCs such as sm8750 and kaanapali. Signed-off-by: Yijie Yang <yijie.yang@oss.qualcomm.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Reviewed-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com> Link: https://patch.msgid.link/20260811-bwmon-v2-1-80f7f150ab9e@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Diffstat (limited to 'fs/btrfs/lru_cache.h')
-rw-r--r--fs/btrfs/lru_cache.h71
1 files changed, 71 insertions, 0 deletions
diff --git a/fs/btrfs/lru_cache.h b/fs/btrfs/lru_cache.h
new file mode 100644
index 000000000..07f1bb1c6
--- /dev/null
+++ b/fs/btrfs/lru_cache.h
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_LRU_CACHE_H
+#define BTRFS_LRU_CACHE_H
+
+#include <linux/types.h>
+#include <linux/maple_tree.h>
+#include <linux/list.h>
+
+/*
+ * A cache entry. This is meant to be embedded in a structure of a user of
+ * this module. Similar to how struct list_head and struct rb_node are used.
+ *
+ * Note: it should be embedded as the first element in a struct (offset 0), and
+ * this module assumes it was allocated with kmalloc(), so it calls kfree() when
+ * it needs to free an entry.
+ */
+struct btrfs_lru_cache_entry {
+ struct list_head lru_list;
+ u64 key;
+ /*
+ * Optional generation associated to a key. Use 0 if not needed/used.
+ * Entries with the same key and different generations are stored in a
+ * linked list, so use this only for cases where there's a small number
+ * of different generations.
+ */
+ u64 gen;
+ /*
+ * The maple tree uses unsigned long type for the keys, which is 32 bits
+ * on 32 bits systems, and 64 bits on 64 bits systems. So if we want to
+ * use something like inode numbers as keys, which are always a u64, we
+ * have to deal with this in a special way - we store the key in the
+ * entry itself, as a u64, and the values inserted into the maple tree
+ * are linked lists of entries - so in case we are on a 64 bits system,
+ * that list always has a single entry, while on 32 bits systems it
+ * may have more than one, with each entry having the same value for
+ * their lower 32 bits of the u64 key.
+ */
+ struct list_head list;
+};
+
+struct btrfs_lru_cache {
+ struct list_head lru_list;
+ struct maple_tree entries;
+ /* Number of entries stored in the cache. */
+ unsigned int size;
+ /* Maximum number of entries the cache can have. */
+ unsigned int max_size;
+};
+
+#define btrfs_lru_cache_for_each_entry_safe(cache, entry, tmp) \
+ list_for_each_entry_safe_reverse((entry), (tmp), &(cache)->lru_list, lru_list)
+
+static inline struct btrfs_lru_cache_entry *btrfs_lru_cache_lru_entry(
+ struct btrfs_lru_cache *cache)
+{
+ return list_first_entry_or_null(&cache->lru_list,
+ struct btrfs_lru_cache_entry, lru_list);
+}
+
+void btrfs_lru_cache_init(struct btrfs_lru_cache *cache, unsigned int max_size);
+struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cache,
+ u64 key, u64 gen);
+int btrfs_lru_cache_store(struct btrfs_lru_cache *cache,
+ struct btrfs_lru_cache_entry *new_entry,
+ gfp_t gfp);
+void btrfs_lru_cache_remove(struct btrfs_lru_cache *cache,
+ struct btrfs_lru_cache_entry *entry);
+void btrfs_lru_cache_clear(struct btrfs_lru_cache *cache);
+
+#endif