/*-
* BSD LICENSE
- *
- * Copyright(c) 2010-2013 Intel Corporation. All rights reserved.
+ *
+ * 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
+ *
+ * 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
+ *
+ * * 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
+ * * 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
+ * * 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
+ *
+ * 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__
* 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-byte cache
+ * 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 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
+ * (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
+ * 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
+ * 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 <rte_common.h>
#include <rte_debug.h>
#include <rte_memory.h>
#include <rte_branch_prediction.h>
#ifndef RTE_BITMAP_OPTIMIZATIONS
#define RTE_BITMAP_OPTIMIZATIONS 1
#endif
-#if RTE_BITMAP_OPTIMIZATIONS
-#include <tmmintrin.h>
-#endif
-
-/** Number of elements in array1. Each element in array1 is a 64-bit slab. */
-#ifndef RTE_BITMAP_ARRAY1_SIZE
-#define RTE_BITMAP_ARRAY1_SIZE 16
-#endif
/* Slab */
#define RTE_BITMAP_SLAB_BIT_SIZE 64
#define RTE_BITMAP_SLAB_BIT_MASK (RTE_BITMAP_SLAB_BIT_SIZE - 1)
/* Cache line (CL) */
-#define RTE_BITMAP_CL_BIT_SIZE (CACHE_LINE_SIZE * 8)
-#define RTE_BITMAP_CL_BIT_SIZE_LOG2 9
+#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 3
+#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 {
- uint64_t array1[RTE_BITMAP_ARRAY1_SIZE]; /**< Bitmap array1 */
+ /* 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 */
-} __rte_cache_aligned;
+
+ /* Storage space for array1 and array2 */
+ uint8_t memory[0];
+};
static inline void
__rte_bitmap_index1_inc(struct rte_bitmap *bmp)
{
- bmp->index1 = (bmp->index1 + 1) & (RTE_BITMAP_ARRAY1_SIZE - 1);
+ 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);
+ return (~1lu) << bmp->offset1;
}
static inline void
#if RTE_BITMAP_OPTIMIZATIONS
-static inline int
+static inline int
rte_bsf64(uint64_t slab, uint32_t *pos)
{
if (likely(slab == 0)) {
#else
-static inline int
+static inline int
rte_bsf64(uint64_t slab, uint32_t *pos)
{
uint64_t mask;
uint32_t i;
-
+
if (likely(slab == 0)) {
return 0;
}
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 = RTE_BITMAP_ARRAY1_SIZE - 1;
+ 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 bmp
- * Handle to bitmap instance
- * @param array2
- * Base address of pre-allocated array2
+ * @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
- * 0 upon success, error code otherwise
+ * Handle to bitmap instance.
*/
-static inline int
-rte_bitmap_init(struct rte_bitmap *bmp, uint8_t *array2, uint32_t n_bits)
+static inline struct rte_bitmap *
+rte_bitmap_init(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
{
- uint32_t array1_size, array2_size;
+ struct rte_bitmap *bmp;
+ uint32_t array1_byte_offset, array1_slabs, array2_byte_offset, array2_slabs;
+ uint32_t size;
/* Check input arguments */
- if ((bmp == NULL) ||
- (array2 == NULL) || (((uintptr_t) array2) & CACHE_LINE_MASK) ||
- (n_bits == 0) || (n_bits & RTE_BITMAP_CL_BIT_MASK)){
- return -1;
+ if (n_bits == 0) {
+ return NULL;
}
- array2_size = n_bits / RTE_BITMAP_SLAB_BIT_SIZE;
- array1_size = ((n_bits / RTE_BITMAP_CL_BIT_SIZE) + (RTE_BITMAP_SLAB_BIT_SIZE - 1)) / RTE_BITMAP_SLAB_BIT_SIZE;
- if (array1_size > RTE_BITMAP_ARRAY1_SIZE){
- return -1;
+ 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(bmp, 0, sizeof(struct rte_bitmap));
- bmp->array2 = (uint64_t *) array2;
- bmp->array1_size = array1_size;
- bmp->array2_size = array2_size;
+ 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 0;
+
+ return bmp;
}
/**
if (bmp == NULL) {
return -1;
}
-
+
return 0;
}
static inline void
rte_bitmap_reset(struct rte_bitmap *bmp)
{
- memset(bmp->array1, 0, sizeof(bmp->array1));
+ 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);
}
{
uint64_t *slab2;
uint32_t index2;
-
+
index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
slab2 = bmp->array2 + index2;
rte_prefetch0((void *) slab2);
{
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));
+ return (*slab2) & (1lu << offset2);
}
/**
{
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;
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;
}
{
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;
}
__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);
+
+ return v1 | v3;
}
/**
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;
{
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 < RTE_BITMAP_ARRAY1_SIZE; i ++, __rte_bitmap_index1_inc(bmp)) {
+ 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;
}
__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;
}
* @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
+ * 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
+ * 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
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;
}