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diff --git a/lib/librte_sched/rte_bitmap.h b/lib/librte_sched/rte_bitmap.h
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+/*-
+ * 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 <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[0];
+};
+
+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__ */