whisper.cpp/examples/talk-llama/llama-kv-cache.h
2025-04-28 16:40:23 +03:00

214 lines
6.2 KiB
C++

#pragma once
#include "llama.h"
#include "llama-io.h"
#include "llama-memory.h"
#include "ggml-cpp.h"
#include <functional>
#include <set>
#include <vector>
struct llama_cparams;
struct llama_hparams;
struct llama_ubatch;
struct llama_kv_cache : public llama_memory_i {
using llama_memory_i::llama_memory_i;
virtual void restore() = 0; // call if batch processing fails - restores the cache state
virtual void commit() = 0; // call after successful batch processing - clears any pending state
virtual int32_t get_n_tokens() const = 0;
virtual int32_t get_used_cells() const = 0; // TODO: remove, this is too-specific to the unified cache
virtual bool get_can_shift() const = 0;
bool get_can_edit() const override { return get_can_shift(); }
};
struct llama_kv_cache_guard {
llama_kv_cache_guard(llama_kv_cache * kv) : kv(kv) {}
~llama_kv_cache_guard() {
kv->restore();
}
void commit() {
kv->commit();
}
private:
llama_kv_cache * kv;
};
struct llama_kv_cell {
llama_pos pos = -1;
llama_pos delta = 0;
int32_t src = -1; // used by recurrent state models to copy states
int32_t tail = -1;
std::set<llama_seq_id> seq_id;
bool has_seq_id(const llama_seq_id & id) const {
return seq_id.find(id) != seq_id.end();
}
bool is_empty() const {
return seq_id.empty();
}
bool is_same_seq(const llama_kv_cell & other) const {
return seq_id == other.seq_id;
}
};
// ring-buffer of cached KV data
// TODO: pimpl
// TODO: add notion of max sequences
class llama_kv_cache_unified : public llama_kv_cache {
public:
// can be used to query data from the model if needed
struct callbacks {
std::function<ggml_tensor * (uint32_t n_ctx_per_seq, int il)> get_rope_factors;
};
llama_kv_cache_unified(
const llama_hparams & hparams,
callbacks cbs);
virtual ~llama_kv_cache_unified() = default;
// TODO: become constructor
bool init(
const llama_model & model, // TODO: do not reference the model
const llama_cparams & cparams,
ggml_type type_k,
ggml_type type_v,
uint32_t kv_size,
bool offload);
int32_t get_n_tokens() const override;
int32_t get_used_cells() const override;
size_t total_size() const;
// TODO: better data structures to reduce the cost of this operation
llama_pos pos_max() const;
void clear() override;
void defrag() override;
virtual void restore() override;
virtual void commit() override;
bool seq_rm (llama_seq_id seq_id, llama_pos p0, llama_pos p1) override;
void seq_cp (llama_seq_id seq_id_src, llama_seq_id seq_id_dst, llama_pos p0, llama_pos p1) override;
void seq_keep(llama_seq_id seq_id) override;
void seq_add (llama_seq_id seq_id, llama_pos p0, llama_pos p1, llama_pos delta) override;
void seq_div (llama_seq_id seq_id, llama_pos p0, llama_pos p1, int d) override;
llama_pos seq_pos_max(llama_seq_id seq_id) const override;
bool get_can_shift() const override;
// find an empty slot of size "n_tokens" in the cache
// updates the cache head
// Note: On success, it's important that cache.head points
// to the first cell of the slot.
bool find_slot(const llama_ubatch & batch);
// TODO: maybe not needed
uint32_t get_padding(const llama_cparams & cparams) const;
// find how many cells are currently in use
uint32_t cell_max() const;
size_t size_k_bytes() const;
size_t size_v_bytes() const;
// defrag
struct {
std::vector<uint32_t> ids;
} defrag_info;
// return true if cells have been moved
bool defrag_prepare(int32_t n_max_nodes);
// commit/restore cache
struct slot_range {
uint32_t c0 = 0; // note: these are cell indices, not sequence positions
uint32_t c1 = 0;
};
// pending cell updates that are not yet committed
struct {
std::vector<slot_range> ranges;
} pending;
// state write/load
void state_write(llama_io_write_i & io, llama_seq_id seq_id = -1) const;
void state_read (llama_io_read_i & io, llama_seq_id seq_id = -1);
// members
const llama_hparams & hparams;
callbacks cbs;
bool has_shift = false;
bool do_defrag = false;
// TODO: remove this and implement llama_kv_cache_recurrent instead
bool recurrent = false; // with recurrent state models, a cell can hold the state for more than one past token
bool v_trans = true; // the value tensor is transposed
bool can_shift = false;
// Note: The value of head isn't only used to optimize searching
// for a free KV slot. llama_decode_impl also uses it, so it
// cannot be freely changed after a slot has been allocated.
uint32_t head = 0;
uint32_t size = 0;
uint32_t used = 0; // used cells (i.e. at least one seq_id)
// computed before each graph build
uint32_t n = 0;
std::vector<llama_kv_cell> cells;
std::vector<ggml_tensor *> k_l; // per layer
std::vector<ggml_tensor *> v_l;
private:
ggml_type type_k = GGML_TYPE_F16;
ggml_type type_v = GGML_TYPE_F16;
std::vector<ggml_context_ptr> ctxs;
std::vector<ggml_backend_buffer_ptr> bufs;
void state_write_meta(llama_io_write_i & io, const std::vector<std::pair<uint32_t, uint32_t>> & cell_ranges, llama_seq_id seq_id = -1) const;
void state_write_data(llama_io_write_i & io, const std::vector<std::pair<uint32_t, uint32_t>> & cell_ranges) const;
bool state_read_meta(llama_io_read_i & io, uint32_t cell_count, llama_seq_id dest_seq_id = -1);
bool state_read_data(llama_io_read_i & io, uint32_t cell_count);
};
// TODO: temporary reusing llama_kv_cache_unified -- implement recurrent cache and simplify llama_kv_cache_unified
//class llama_kv_cache_recurrent : public llama_kv_cache_unified {
//public:
// using llama_kv_cache_unified::llama_kv_cache_unified;
//};
//
// kv cache view
//
llama_kv_cache_view llama_kv_cache_view_init(const llama_kv_cache & kv, int32_t n_seq_max);
void llama_kv_cache_view_update(llama_kv_cache_view * view, const llama_kv_cache * kv);