+++ /dev/null
-/*
- * SPDX-License-Identifier: LGPL-2.1-or-later
- *
- * Copyright 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright 2011 Lai Jiangshan <laijs@cn.fujitsu.com>
- *
- * Internal header for Lock-Free RCU Hash Table
- */
-
-#ifndef _LTTNG_UST_RCULFHASH_INTERNAL_H
-#define _LTTNG_UST_RCULFHASH_INTERNAL_H
-
-#include "rculfhash.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <assert.h>
-
-#ifdef DEBUG
-#define dbg_printf(fmt, args...) printf("[debug lttng-ust rculfhash] " fmt, ## args)
-#else
-#define dbg_printf(fmt, args...) \
-do { \
- /* do nothing but check printf format */ \
- if (0) \
- printf("[debug lttng-ust rculfhash] " fmt, ## args); \
-} while (0)
-#endif
-
-#if (CAA_BITS_PER_LONG == 32)
-#define MAX_TABLE_ORDER 32
-#else
-#define MAX_TABLE_ORDER 64
-#endif
-
-#define MAX_CHUNK_TABLE (1UL << 10)
-
-#ifndef min
-#define min(a, b) ((a) < (b) ? (a) : (b))
-#endif
-
-#ifndef max
-#define max(a, b) ((a) > (b) ? (a) : (b))
-#endif
-
-/*
- * lttng_ust_lfht: Top-level data structure representing a lock-free hash
- * table. Defined in the implementation file to make it be an opaque
- * cookie to users.
- *
- * The fields used in fast-paths are placed near the end of the
- * structure, because we need to have a variable-sized union to contain
- * the mm plugin fields, which are used in the fast path.
- */
-struct lttng_ust_lfht {
- /* Initial configuration items */
- unsigned long max_nr_buckets;
- const struct lttng_ust_lfht_mm_type *mm; /* memory management plugin */
- const struct rcu_flavor_struct *flavor; /* RCU flavor */
-
- /*
- * We need to put the work threads offline (QSBR) when taking this
- * mutex, because we use synchronize_rcu within this mutex critical
- * section, which waits on read-side critical sections, and could
- * therefore cause grace-period deadlock if we hold off RCU G.P.
- * completion.
- */
- pthread_mutex_t resize_mutex; /* resize mutex: add/del mutex */
- unsigned int in_progress_destroy;
- unsigned long resize_target;
- int resize_initiated;
-
- /*
- * Variables needed for add and remove fast-paths.
- */
- int flags;
- unsigned long min_alloc_buckets_order;
- unsigned long min_nr_alloc_buckets;
-
- /*
- * Variables needed for the lookup, add and remove fast-paths.
- */
- unsigned long size; /* always a power of 2, shared (RCU) */
- /*
- * bucket_at pointer is kept here to skip the extra level of
- * dereference needed to get to "mm" (this is a fast-path).
- */
- struct lttng_ust_lfht_node *(*bucket_at)(struct lttng_ust_lfht *ht,
- unsigned long index);
- /*
- * Dynamic length "tbl_chunk" needs to be at the end of
- * lttng_ust_lfht.
- */
- union {
- /*
- * Contains the per order-index-level bucket node table.
- * The size of each bucket node table is half the number
- * of hashes contained in this order (except for order 0).
- * The minimum allocation buckets size parameter allows
- * combining the bucket node arrays of the lowermost
- * levels to improve cache locality for small index orders.
- */
- struct lttng_ust_lfht_node *tbl_order[MAX_TABLE_ORDER];
-
- /*
- * Contains the bucket node chunks. The size of each
- * bucket node chunk is ->min_alloc_size (we avoid to
- * allocate chunks with different size). Chunks improve
- * cache locality for small index orders, and are more
- * friendly with environments where allocation of large
- * contiguous memory areas is challenging due to memory
- * fragmentation concerns or inability to use virtual
- * memory addressing.
- */
- struct lttng_ust_lfht_node *tbl_chunk[0];
-
- /*
- * Memory mapping with room for all possible buckets.
- * Their memory is allocated when needed.
- */
- struct lttng_ust_lfht_node *tbl_mmap;
- };
- /*
- * End of variables needed for the lookup, add and remove
- * fast-paths.
- */
-};
-
-extern unsigned int lttng_ust_lfht_fls_ulong(unsigned long x)
- __attribute__((visibility("hidden")));
-
-extern int lttng_ust_lfht_get_count_order_u32(uint32_t x)
- __attribute__((visibility("hidden")));
-
-extern int lttng_ust_lfht_get_count_order_ulong(unsigned long x)
- __attribute__((visibility("hidden")));
-
-#ifdef POISON_FREE
-#define poison_free(ptr) \
- do { \
- if (ptr) { \
- memset(ptr, 0x42, sizeof(*(ptr))); \
- free(ptr); \
- } \
- } while (0)
-#else
-#define poison_free(ptr) free(ptr)
-#endif
-
-static inline
-struct lttng_ust_lfht *__default_alloc_lttng_ust_lfht(
- const struct lttng_ust_lfht_mm_type *mm,
- unsigned long lttng_ust_lfht_size,
- unsigned long min_nr_alloc_buckets,
- unsigned long max_nr_buckets)
-{
- struct lttng_ust_lfht *ht;
-
- ht = calloc(1, lttng_ust_lfht_size);
- assert(ht);
-
- ht->mm = mm;
- ht->bucket_at = mm->bucket_at;
- ht->min_nr_alloc_buckets = min_nr_alloc_buckets;
- ht->min_alloc_buckets_order =
- lttng_ust_lfht_get_count_order_ulong(min_nr_alloc_buckets);
- ht->max_nr_buckets = max_nr_buckets;
-
- return ht;
-}
-
-#endif /* _LTTNG_UST_RCULFHASH_INTERNAL_H */
projects / lttng-ust.git / blobdiff