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Diffstat (limited to 'src/vppinfra/smp_fifo.h')
-rw-r--r-- | src/vppinfra/smp_fifo.h | 313 |
1 files changed, 0 insertions, 313 deletions
diff --git a/src/vppinfra/smp_fifo.h b/src/vppinfra/smp_fifo.h deleted file mode 100644 index c74a77c8e9b..00000000000 --- a/src/vppinfra/smp_fifo.h +++ /dev/null @@ -1,313 +0,0 @@ -/* - * Copyright (c) 2015 Cisco and/or its affiliates. - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at: - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ -/* - Copyright (c) 2012 Eliot Dresselhaus - - Permission is hereby granted, free of charge, to any person obtaining - a copy of this software and associated documentation files (the - "Software"), to deal in the Software without restriction, including - without limitation the rights to use, copy, modify, merge, publish, - distribute, sublicense, and/or sell copies of the Software, and to - permit persons to whom the Software is furnished to do so, subject to - the following conditions: - - The above copyright notice and this permission notice shall be - included in all copies or substantial portions of the Software. - - THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, - EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF - MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND - NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE - LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION - OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION - WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. -*/ - -#ifndef included_clib_smp_vec_h -#define included_clib_smp_vec_h - -#include <vppinfra/smp.h> - -#define foreach_clib_smp_fifo_data_state \ - _ (free) \ - _ (write_alloc) \ - _ (write_done) \ - _ (read_fetch) - -typedef enum -{ -#define _(f) CLIB_SMP_FIFO_DATA_STATE_##f, - foreach_clib_smp_fifo_data_state -#undef _ - CLIB_SMP_FIFO_N_DATA_STATE, -} clib_smp_fifo_data_state_t; - -/* Footer at end of each data element. */ -typedef struct -{ - /* Magic number marking valid footer plus state encoded in low bits. */ - u32 magic_state; -} clib_smp_fifo_data_footer_t; - -#define CLIB_SMP_DATA_FOOTER_MAGIC 0xfafbfcf0 - -always_inline clib_smp_fifo_data_state_t -clib_smp_fifo_data_footer_get_state (clib_smp_fifo_data_footer_t * f) -{ - u32 s = f->magic_state - CLIB_SMP_DATA_FOOTER_MAGIC; - - /* Check that magic number plus state is still valid. */ - if (s >= CLIB_SMP_FIFO_N_DATA_STATE) - os_panic (); - - return s; -} - -always_inline void -clib_smp_fifo_data_footer_set_state (clib_smp_fifo_data_footer_t * f, - clib_smp_fifo_data_state_t s) -{ - f->magic_state = CLIB_SMP_DATA_FOOTER_MAGIC + s; -} - -typedef struct -{ - /* Read/write indices each on their own cache line. - Atomic incremented for each read/write. */ - u32 read_index, write_index; - - /* Power of 2 number of elements in fifo less one. */ - u32 max_n_elts_less_one; - - /* Log2 of above. */ - u32 log2_max_n_elts; - - /* Cache aligned data. */ - void *data; -} clib_smp_fifo_t; - -/* External functions. */ -clib_smp_fifo_t *clib_smp_fifo_init (uword max_n_elts, uword n_bytes_per_elt); - -/* Elements are always cache-line sized; this is to avoid smp cache thrashing. */ -always_inline uword -clib_smp_fifo_round_elt_bytes (uword n_bytes_per_elt) -{ - return round_pow2 (n_bytes_per_elt, CLIB_CACHE_LINE_BYTES); -} - -always_inline uword -clib_smp_fifo_n_elts (clib_smp_fifo_t * f) -{ - uword n = f->write_index - f->read_index; - ASSERT (n <= f->max_n_elts_less_one + 1); - return n; -} - -always_inline clib_smp_fifo_data_footer_t * -clib_smp_fifo_get_data_footer (void *d, uword n_bytes_per_elt) -{ - clib_smp_fifo_data_footer_t *f; - f = d + clib_smp_fifo_round_elt_bytes (n_bytes_per_elt) - sizeof (f[0]); - return f; -} - -always_inline void * -clib_smp_fifo_elt_at_index (clib_smp_fifo_t * f, uword n_bytes_per_elt, - uword i) -{ - uword n_bytes_per_elt_cache_aligned; - - ASSERT (i <= f->max_n_elts_less_one); - - n_bytes_per_elt_cache_aligned = - clib_smp_fifo_round_elt_bytes (n_bytes_per_elt); - - return f->data + i * n_bytes_per_elt_cache_aligned; -} - -always_inline void * -clib_smp_fifo_write_alloc (clib_smp_fifo_t * f, uword n_bytes_per_elt) -{ - void *d; - clib_smp_fifo_data_footer_t *t; - clib_smp_fifo_data_state_t s; - u32 wi0, wi1; - - wi0 = f->write_index; - - /* Fifo full? */ - if (wi0 - f->read_index > f->max_n_elts_less_one) - return 0; - - while (1) - { - wi1 = wi0 + 1; - - d = - clib_smp_fifo_elt_at_index (f, n_bytes_per_elt, - wi0 & f->max_n_elts_less_one); - t = clib_smp_fifo_get_data_footer (d, n_bytes_per_elt); - - s = clib_smp_fifo_data_footer_get_state (t); - if (s != CLIB_SMP_FIFO_DATA_STATE_free) - { - d = 0; - break; - } - - wi1 = clib_smp_compare_and_swap (&f->write_index, wi1, wi0); - - if (wi1 == wi0) - { - clib_smp_fifo_data_footer_set_state (t, - CLIB_SMP_FIFO_DATA_STATE_write_alloc); - break; - } - - /* Other cpu wrote write index first: try again. */ - wi0 = wi1; - } - - return d; -} - -always_inline void -clib_smp_fifo_write_done (clib_smp_fifo_t * f, void *d, uword n_bytes_per_elt) -{ - clib_smp_fifo_data_footer_t *t; - - /* Flush out pending writes before we change state to write_done. - This will hold off readers until data is flushed. */ - CLIB_MEMORY_BARRIER (); - - t = clib_smp_fifo_get_data_footer (d, n_bytes_per_elt); - - ASSERT (clib_smp_fifo_data_footer_get_state (t) == - CLIB_SMP_FIFO_DATA_STATE_write_alloc); - clib_smp_fifo_data_footer_set_state (t, - CLIB_SMP_FIFO_DATA_STATE_write_done); -} - -always_inline void * -clib_smp_fifo_read_fetch (clib_smp_fifo_t * f, uword n_bytes_per_elt) -{ - void *d; - clib_smp_fifo_data_footer_t *t; - clib_smp_fifo_data_state_t s; - u32 ri0, ri1; - - ri0 = f->read_index; - - /* Fifo empty? */ - if (f->write_index - ri0 == 0) - return 0; - - while (1) - { - ri1 = ri0 + 1; - - d = - clib_smp_fifo_elt_at_index (f, n_bytes_per_elt, - ri0 & f->max_n_elts_less_one); - t = clib_smp_fifo_get_data_footer (d, n_bytes_per_elt); - - s = clib_smp_fifo_data_footer_get_state (t); - if (s != CLIB_SMP_FIFO_DATA_STATE_write_done) - { - d = 0; - break; - } - - ri1 = clib_smp_compare_and_swap (&f->read_index, ri1, ri0); - if (ri1 == ri0) - { - clib_smp_fifo_data_footer_set_state (t, - CLIB_SMP_FIFO_DATA_STATE_read_fetch); - break; - } - - ri0 = ri1; - } - - return d; -} - -always_inline void -clib_smp_fifo_read_done (clib_smp_fifo_t * f, void *d, uword n_bytes_per_elt) -{ - clib_smp_fifo_data_footer_t *t; - - t = clib_smp_fifo_get_data_footer (d, n_bytes_per_elt); - - ASSERT (clib_smp_fifo_data_footer_get_state (t) == - CLIB_SMP_FIFO_DATA_STATE_read_fetch); - clib_smp_fifo_data_footer_set_state (t, CLIB_SMP_FIFO_DATA_STATE_free); -} - -always_inline void -clib_smp_fifo_memcpy (uword * dst, uword * src, uword n_bytes) -{ - word n_bytes_left = n_bytes; - - while (n_bytes_left >= 4 * sizeof (uword)) - { - dst[0] = src[0]; - dst[1] = src[1]; - dst[2] = src[2]; - dst[3] = src[3]; - dst += 4; - src += 4; - n_bytes_left -= 4 * sizeof (dst[0]); - } - - while (n_bytes_left > 0) - { - dst[0] = src[0]; - dst += 1; - src += 1; - n_bytes_left -= 1 * sizeof (dst[0]); - } -} - -always_inline void -clib_smp_fifo_write_inline (clib_smp_fifo_t * f, void *elt_to_write, - uword n_bytes_per_elt) -{ - uword *dst; - dst = clib_smp_fifo_write_alloc (f, n_bytes_per_elt); - clib_smp_fifo_memcpy (dst, elt_to_write, n_bytes_per_elt); - clib_smp_fifo_write_done (f, dst, n_bytes_per_elt); -} - -always_inline void -clib_smp_fifo_read_inline (clib_smp_fifo_t * f, void *elt_to_read, - uword n_bytes_per_elt) -{ - uword *src; - src = clib_smp_fifo_read_fetch (f, n_bytes_per_elt); - clib_smp_fifo_memcpy (elt_to_read, src, n_bytes_per_elt); - clib_smp_fifo_read_done (f, src, n_bytes_per_elt); -} - -#endif /* included_clib_smp_vec_h */ - -/* - * fd.io coding-style-patch-verification: ON - * - * Local Variables: - * eval: (c-set-style "gnu") - * End: - */ |