+++ /dev/null
-/*-
- * BSD LICENSE
- *
- * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * * Neither the name of Intel Corporation nor the names of its
- * contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef __INCLUDE_RTE_BITMAP_H__
-#define __INCLUDE_RTE_BITMAP_H__
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
- * @file
- * RTE Bitmap
- *
- * The bitmap component provides a mechanism to manage large arrays of bits
- * through bit get/set/clear and bit array scan operations.
- *
- * The bitmap scan operation is optimized for 64-bit CPUs using 64/128 byte cache
- * lines. The bitmap is hierarchically organized using two arrays (array1 and
- * array2), with each bit in array1 being associated with a full cache line
- * (512/1024 bits) of bitmap bits, which are stored in array2: the bit in array1
- * is set only when there is at least one bit set within its associated array2
- * bits, otherwise the bit in array1 is cleared. The read and write operations
- * for array1 and array2 are always done in slabs of 64 bits.
- *
- * This bitmap is not thread safe. For lock free operation on a specific bitmap
- * instance, a single writer thread performing bit set/clear operations is
- * allowed, only the writer thread can do bitmap scan operations, while there
- * can be several reader threads performing bit get operations in parallel with
- * the writer thread. When the use of locking primitives is acceptable, the
- * serialization of the bit set/clear and bitmap scan operations needs to be
- * enforced by the caller, while the bit get operation does not require locking
- * the bitmap.
- *
- ***/
-
-#include <string.h>
-#include <rte_common.h>
-#include <rte_debug.h>
-#include <rte_memory.h>
-#include <rte_branch_prediction.h>
-#include <rte_prefetch.h>
-
-#ifndef RTE_BITMAP_OPTIMIZATIONS
-#define RTE_BITMAP_OPTIMIZATIONS 1
-#endif
-
-/* Slab */
-#define RTE_BITMAP_SLAB_BIT_SIZE 64
-#define RTE_BITMAP_SLAB_BIT_SIZE_LOG2 6
-#define RTE_BITMAP_SLAB_BIT_MASK (RTE_BITMAP_SLAB_BIT_SIZE - 1)
-
-/* Cache line (CL) */
-#define RTE_BITMAP_CL_BIT_SIZE (RTE_CACHE_LINE_SIZE * 8)
-#define RTE_BITMAP_CL_BIT_SIZE_LOG2 (RTE_CACHE_LINE_SIZE_LOG2 + 3)
-#define RTE_BITMAP_CL_BIT_MASK (RTE_BITMAP_CL_BIT_SIZE - 1)
-
-#define RTE_BITMAP_CL_SLAB_SIZE (RTE_BITMAP_CL_BIT_SIZE / RTE_BITMAP_SLAB_BIT_SIZE)
-#define RTE_BITMAP_CL_SLAB_SIZE_LOG2 (RTE_BITMAP_CL_BIT_SIZE_LOG2 - RTE_BITMAP_SLAB_BIT_SIZE_LOG2)
-#define RTE_BITMAP_CL_SLAB_MASK (RTE_BITMAP_CL_SLAB_SIZE - 1)
-
-/** Bitmap data structure */
-struct rte_bitmap {
- /* Context for array1 and array2 */
- uint64_t *array1; /**< Bitmap array1 */
- uint64_t *array2; /**< Bitmap array2 */
- uint32_t array1_size; /**< Number of 64-bit slabs in array1 that are actually used */
- uint32_t array2_size; /**< Number of 64-bit slabs in array2 */
-
- /* Context for the "scan next" operation */
- uint32_t index1; /**< Bitmap scan: Index of current array1 slab */
- uint32_t offset1; /**< Bitmap scan: Offset of current bit within current array1 slab */
- uint32_t index2; /**< Bitmap scan: Index of current array2 slab */
- uint32_t go2; /**< Bitmap scan: Go/stop condition for current array2 cache line */
-
- /* Storage space for array1 and array2 */
- uint8_t memory[];
-};
-
-static inline void
-__rte_bitmap_index1_inc(struct rte_bitmap *bmp)
-{
- bmp->index1 = (bmp->index1 + 1) & (bmp->array1_size - 1);
-}
-
-static inline uint64_t
-__rte_bitmap_mask1_get(struct rte_bitmap *bmp)
-{
- return (~1lu) << bmp->offset1;
-}
-
-static inline void
-__rte_bitmap_index2_set(struct rte_bitmap *bmp)
-{
- bmp->index2 = (((bmp->index1 << RTE_BITMAP_SLAB_BIT_SIZE_LOG2) + bmp->offset1) << RTE_BITMAP_CL_SLAB_SIZE_LOG2);
-}
-
-#if RTE_BITMAP_OPTIMIZATIONS
-
-static inline int
-rte_bsf64(uint64_t slab, uint32_t *pos)
-{
- if (likely(slab == 0)) {
- return 0;
- }
-
- *pos = __builtin_ctzll(slab);
- return 1;
-}
-
-#else
-
-static inline int
-rte_bsf64(uint64_t slab, uint32_t *pos)
-{
- uint64_t mask;
- uint32_t i;
-
- if (likely(slab == 0)) {
- return 0;
- }
-
- for (i = 0, mask = 1; i < RTE_BITMAP_SLAB_BIT_SIZE; i ++, mask <<= 1) {
- if (unlikely(slab & mask)) {
- *pos = i;
- return 1;
- }
- }
-
- return 0;
-}
-
-#endif
-
-static inline uint32_t
-__rte_bitmap_get_memory_footprint(uint32_t n_bits,
- uint32_t *array1_byte_offset, uint32_t *array1_slabs,
- uint32_t *array2_byte_offset, uint32_t *array2_slabs)
-{
- uint32_t n_slabs_context, n_slabs_array1, n_cache_lines_context_and_array1;
- uint32_t n_cache_lines_array2;
- uint32_t n_bytes_total;
-
- n_cache_lines_array2 = (n_bits + RTE_BITMAP_CL_BIT_SIZE - 1) / RTE_BITMAP_CL_BIT_SIZE;
- n_slabs_array1 = (n_cache_lines_array2 + RTE_BITMAP_SLAB_BIT_SIZE - 1) / RTE_BITMAP_SLAB_BIT_SIZE;
- n_slabs_array1 = rte_align32pow2(n_slabs_array1);
- n_slabs_context = (sizeof(struct rte_bitmap) + (RTE_BITMAP_SLAB_BIT_SIZE / 8) - 1) / (RTE_BITMAP_SLAB_BIT_SIZE / 8);
- n_cache_lines_context_and_array1 = (n_slabs_context + n_slabs_array1 + RTE_BITMAP_CL_SLAB_SIZE - 1) / RTE_BITMAP_CL_SLAB_SIZE;
- n_bytes_total = (n_cache_lines_context_and_array1 + n_cache_lines_array2) * RTE_CACHE_LINE_SIZE;
-
- if (array1_byte_offset) {
- *array1_byte_offset = n_slabs_context * (RTE_BITMAP_SLAB_BIT_SIZE / 8);
- }
- if (array1_slabs) {
- *array1_slabs = n_slabs_array1;
- }
- if (array2_byte_offset) {
- *array2_byte_offset = n_cache_lines_context_and_array1 * RTE_CACHE_LINE_SIZE;
- }
- if (array2_slabs) {
- *array2_slabs = n_cache_lines_array2 * RTE_BITMAP_CL_SLAB_SIZE;
- }
-
- return n_bytes_total;
-}
-
-static inline void
-__rte_bitmap_scan_init(struct rte_bitmap *bmp)
-{
- bmp->index1 = bmp->array1_size - 1;
- bmp->offset1 = RTE_BITMAP_SLAB_BIT_SIZE - 1;
- __rte_bitmap_index2_set(bmp);
- bmp->index2 += RTE_BITMAP_CL_SLAB_SIZE;
-
- bmp->go2 = 0;
-}
-
-/**
- * Bitmap memory footprint calculation
- *
- * @param n_bits
- * Number of bits in the bitmap
- * @return
- * Bitmap memory footprint measured in bytes on success, 0 on error
- */
-static inline uint32_t
-rte_bitmap_get_memory_footprint(uint32_t n_bits) {
- /* Check input arguments */
- if (n_bits == 0) {
- return 0;
- }
-
- return __rte_bitmap_get_memory_footprint(n_bits, NULL, NULL, NULL, NULL);
-}
-
-/**
- * Bitmap initialization
- *
- * @param mem_size
- * Minimum expected size of bitmap.
- * @param mem
- * Base address of array1 and array2.
- * @param n_bits
- * Number of pre-allocated bits in array2. Must be non-zero and multiple of 512.
- * @return
- * Handle to bitmap instance.
- */
-static inline struct rte_bitmap *
-rte_bitmap_init(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
-{
- struct rte_bitmap *bmp;
- uint32_t array1_byte_offset, array1_slabs, array2_byte_offset, array2_slabs;
- uint32_t size;
-
- /* Check input arguments */
- if (n_bits == 0) {
- return NULL;
- }
-
- if ((mem == NULL) || (((uintptr_t) mem) & RTE_CACHE_LINE_MASK)) {
- return NULL;
- }
-
- size = __rte_bitmap_get_memory_footprint(n_bits,
- &array1_byte_offset, &array1_slabs,
- &array2_byte_offset, &array2_slabs);
- if (size < mem_size) {
- return NULL;
- }
-
- /* Setup bitmap */
- memset(mem, 0, size);
- bmp = (struct rte_bitmap *) mem;
-
- bmp->array1 = (uint64_t *) &mem[array1_byte_offset];
- bmp->array1_size = array1_slabs;
- bmp->array2 = (uint64_t *) &mem[array2_byte_offset];
- bmp->array2_size = array2_slabs;
-
- __rte_bitmap_scan_init(bmp);
-
- return bmp;
-}
-
-/**
- * Bitmap free
- *
- * @param bmp
- * Handle to bitmap instance
- * @return
- * 0 upon success, error code otherwise
- */
-static inline int
-rte_bitmap_free(struct rte_bitmap *bmp)
-{
- /* Check input arguments */
- if (bmp == NULL) {
- return -1;
- }
-
- return 0;
-}
-
-/**
- * Bitmap reset
- *
- * @param bmp
- * Handle to bitmap instance
- */
-static inline void
-rte_bitmap_reset(struct rte_bitmap *bmp)
-{
- memset(bmp->array1, 0, bmp->array1_size * sizeof(uint64_t));
- memset(bmp->array2, 0, bmp->array2_size * sizeof(uint64_t));
- __rte_bitmap_scan_init(bmp);
-}
-
-/**
- * Bitmap location prefetch into CPU L1 cache
- *
- * @param bmp
- * Handle to bitmap instance
- * @param pos
- * Bit position
- * @return
- * 0 upon success, error code otherwise
- */
-static inline void
-rte_bitmap_prefetch0(struct rte_bitmap *bmp, uint32_t pos)
-{
- uint64_t *slab2;
- uint32_t index2;
-
- index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
- slab2 = bmp->array2 + index2;
- rte_prefetch0((void *) slab2);
-}
-
-/**
- * Bitmap bit get
- *
- * @param bmp
- * Handle to bitmap instance
- * @param pos
- * Bit position
- * @return
- * 0 when bit is cleared, non-zero when bit is set
- */
-static inline uint64_t
-rte_bitmap_get(struct rte_bitmap *bmp, uint32_t pos)
-{
- uint64_t *slab2;
- uint32_t index2, offset2;
-
- index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
- offset2 = pos & RTE_BITMAP_SLAB_BIT_MASK;
- slab2 = bmp->array2 + index2;
- return (*slab2) & (1lu << offset2);
-}
-
-/**
- * Bitmap bit set
- *
- * @param bmp
- * Handle to bitmap instance
- * @param pos
- * Bit position
- */
-static inline void
-rte_bitmap_set(struct rte_bitmap *bmp, uint32_t pos)
-{
- uint64_t *slab1, *slab2;
- uint32_t index1, index2, offset1, offset2;
-
- /* Set bit in array2 slab and set bit in array1 slab */
- index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
- offset2 = pos & RTE_BITMAP_SLAB_BIT_MASK;
- index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 + RTE_BITMAP_CL_BIT_SIZE_LOG2);
- offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) & RTE_BITMAP_SLAB_BIT_MASK;
- slab2 = bmp->array2 + index2;
- slab1 = bmp->array1 + index1;
-
- *slab2 |= 1lu << offset2;
- *slab1 |= 1lu << offset1;
-}
-
-/**
- * Bitmap slab set
- *
- * @param bmp
- * Handle to bitmap instance
- * @param pos
- * Bit position identifying the array2 slab
- * @param slab
- * Value to be assigned to the 64-bit slab in array2
- */
-static inline void
-rte_bitmap_set_slab(struct rte_bitmap *bmp, uint32_t pos, uint64_t slab)
-{
- uint64_t *slab1, *slab2;
- uint32_t index1, index2, offset1;
-
- /* Set bits in array2 slab and set bit in array1 slab */
- index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
- index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 + RTE_BITMAP_CL_BIT_SIZE_LOG2);
- offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) & RTE_BITMAP_SLAB_BIT_MASK;
- slab2 = bmp->array2 + index2;
- slab1 = bmp->array1 + index1;
-
- *slab2 |= slab;
- *slab1 |= 1lu << offset1;
-}
-
-static inline uint64_t
-__rte_bitmap_line_not_empty(uint64_t *slab2)
-{
- uint64_t v1, v2, v3, v4;
-
- v1 = slab2[0] | slab2[1];
- v2 = slab2[2] | slab2[3];
- v3 = slab2[4] | slab2[5];
- v4 = slab2[6] | slab2[7];
- v1 |= v2;
- v3 |= v4;
-
- return v1 | v3;
-}
-
-/**
- * Bitmap bit clear
- *
- * @param bmp
- * Handle to bitmap instance
- * @param pos
- * Bit position
- */
-static inline void
-rte_bitmap_clear(struct rte_bitmap *bmp, uint32_t pos)
-{
- uint64_t *slab1, *slab2;
- uint32_t index1, index2, offset1, offset2;
-
- /* Clear bit in array2 slab */
- index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
- offset2 = pos & RTE_BITMAP_SLAB_BIT_MASK;
- slab2 = bmp->array2 + index2;
-
- /* Return if array2 slab is not all-zeros */
- *slab2 &= ~(1lu << offset2);
- if (*slab2){
- return;
- }
-
- /* Check the entire cache line of array2 for all-zeros */
- index2 &= ~ RTE_BITMAP_CL_SLAB_MASK;
- slab2 = bmp->array2 + index2;
- if (__rte_bitmap_line_not_empty(slab2)) {
- return;
- }
-
- /* The array2 cache line is all-zeros, so clear bit in array1 slab */
- index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 + RTE_BITMAP_CL_BIT_SIZE_LOG2);
- offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) & RTE_BITMAP_SLAB_BIT_MASK;
- slab1 = bmp->array1 + index1;
- *slab1 &= ~(1lu << offset1);
-
- return;
-}
-
-static inline int
-__rte_bitmap_scan_search(struct rte_bitmap *bmp)
-{
- uint64_t value1;
- uint32_t i;
-
- /* Check current array1 slab */
- value1 = bmp->array1[bmp->index1];
- value1 &= __rte_bitmap_mask1_get(bmp);
-
- if (rte_bsf64(value1, &bmp->offset1)) {
- return 1;
- }
-
- __rte_bitmap_index1_inc(bmp);
- bmp->offset1 = 0;
-
- /* Look for another array1 slab */
- for (i = 0; i < bmp->array1_size; i ++, __rte_bitmap_index1_inc(bmp)) {
- value1 = bmp->array1[bmp->index1];
-
- if (rte_bsf64(value1, &bmp->offset1)) {
- return 1;
- }
- }
-
- return 0;
-}
-
-static inline void
-__rte_bitmap_scan_read_init(struct rte_bitmap *bmp)
-{
- __rte_bitmap_index2_set(bmp);
- bmp->go2 = 1;
- rte_prefetch1((void *)(bmp->array2 + bmp->index2 + 8));
-}
-
-static inline int
-__rte_bitmap_scan_read(struct rte_bitmap *bmp, uint32_t *pos, uint64_t *slab)
-{
- uint64_t *slab2;
-
- slab2 = bmp->array2 + bmp->index2;
- for ( ; bmp->go2 ; bmp->index2 ++, slab2 ++, bmp->go2 = bmp->index2 & RTE_BITMAP_CL_SLAB_MASK) {
- if (*slab2) {
- *pos = bmp->index2 << RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
- *slab = *slab2;
-
- bmp->index2 ++;
- slab2 ++;
- bmp->go2 = bmp->index2 & RTE_BITMAP_CL_SLAB_MASK;
- return 1;
- }
- }
-
- return 0;
-}
-
-/**
- * Bitmap scan (with automatic wrap-around)
- *
- * @param bmp
- * Handle to bitmap instance
- * @param pos
- * When function call returns 1, pos contains the position of the next set
- * bit, otherwise not modified
- * @param slab
- * When function call returns 1, slab contains the value of the entire 64-bit
- * slab where the bit indicated by pos is located. Slabs are always 64-bit
- * aligned, so the position of the first bit of the slab (this bit is not
- * necessarily set) is pos / 64. Once a slab has been returned by the bitmap
- * scan operation, the internal pointers of the bitmap are updated to point
- * after this slab, so the same slab will not be returned again if it
- * contains more than one bit which is set. When function call returns 0,
- * slab is not modified.
- * @return
- * 0 if there is no bit set in the bitmap, 1 otherwise
- */
-static inline int
-rte_bitmap_scan(struct rte_bitmap *bmp, uint32_t *pos, uint64_t *slab)
-{
- /* Return data from current array2 line if available */
- if (__rte_bitmap_scan_read(bmp, pos, slab)) {
- return 1;
- }
-
- /* Look for non-empty array2 line */
- if (__rte_bitmap_scan_search(bmp)) {
- __rte_bitmap_scan_read_init(bmp);
- __rte_bitmap_scan_read(bmp, pos, slab);
- return 1;
- }
-
- /* Empty bitmap */
- return 0;
-}
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* __INCLUDE_RTE_BITMAP_H__ */
git.droids-corp.org / dpdk.git / blobdiff