From 344ce4277885e448912fdfc35bcfaf130c74d086 Mon Sep 17 00:00:00 2001 From: Florin Coras Date: Fri, 3 May 2019 11:46:55 -0700 Subject: [PATCH] session/svm: apis for fifo shrinking Change-Id: Ie519683bb90aae6fb95f2a09e251cded1890ed41 Signed-off-by: Florin Coras --- src/plugins/unittest/svm_fifo_test.c | 75 ++++++++++++++++++++++++++++++++++++ src/svm/fifo_segment.c | 29 ++++++++++++++ src/svm/fifo_segment.h | 9 +++++ src/svm/svm_fifo.c | 5 ++- src/vnet/session/segment_manager.c | 31 +++++++++++++++ src/vnet/session/segment_manager.h | 34 ++++++++++++++++ 6 files changed, 182 insertions(+), 1 deletion(-) diff --git a/src/plugins/unittest/svm_fifo_test.c b/src/plugins/unittest/svm_fifo_test.c index 7d83b105c93..8067c6b6b1b 100644 --- a/src/plugins/unittest/svm_fifo_test.c +++ b/src/plugins/unittest/svm_fifo_test.c @@ -2020,6 +2020,74 @@ sfifo_test_fifo_segment_fifo_grow (int verbose) return 0; } +static int +sfifo_test_fifo_segment_fifo_shrink (int verbose) +{ + fifo_segment_main_t *sm = &segment_main; + fifo_segment_create_args_t _a, *a = &_a; + int i, rv, chunk_size = 4096, n_chunks; + fifo_segment_t *fs; + svm_fifo_t *f; + + clib_memset (a, 0, sizeof (*a)); + a->segment_name = "fifo-test1"; + a->segment_size = 256 << 10; + + rv = fifo_segment_create (sm, a); + + SFIFO_TEST (!rv, "svm_fifo_segment_create returned %d", rv); + + /* + * Alloc and grow fifo + */ + fs = fifo_segment_get_segment (sm, a->new_segment_indices[0]); + f = fifo_segment_alloc_fifo (fs, chunk_size, FIFO_SEGMENT_RX_FIFO); + + SFIFO_TEST (f != 0, "svm_fifo_segment_alloc_fifo"); + + for (i = 0; i < 9; i++) + { + fifo_segment_grow_fifo (fs, f, chunk_size); + if (f->size != (i + 2) * chunk_size) + SFIFO_TEST (0, "fifo size should be %u is %u", + (i + 2) * chunk_size, f->size); + } + + rv = svm_fifo_reduce_size (f, 3.5 * chunk_size, 1 /* is producer */ ); + SFIFO_TEST (rv == 3 * chunk_size, "len expected %u is %u", 3 * chunk_size, + rv); + + n_chunks = fifo_segment_num_free_chunks (fs, chunk_size); + SFIFO_TEST (n_chunks == 0, "free chunks should be %u is %u", 0, n_chunks); + + fifo_segment_collect_fifo_chunks (fs, f); + + n_chunks = fifo_segment_num_free_chunks (fs, chunk_size); + SFIFO_TEST (n_chunks == 3, "free chunks should be %u is %u", 3, n_chunks); + + rv = svm_fifo_reduce_size (f, 7 * chunk_size - 1, 1 /* is producer */ ); + SFIFO_TEST (rv == 6 * chunk_size, "len expected %u is %u", 6 * chunk_size, + rv); + + fifo_segment_collect_fifo_chunks (fs, f); + + n_chunks = fifo_segment_num_free_chunks (fs, chunk_size); + SFIFO_TEST (n_chunks == 9, "free chunks should be %u is %u", 9, n_chunks); + /* + * Free + */ + fifo_segment_free_fifo (fs, f); + n_chunks = fifo_segment_num_free_chunks (fs, ~0); + SFIFO_TEST (n_chunks == 9, "free chunks should be %u is %u", 9, n_chunks); + + /* + * Cleanup + */ + fifo_segment_delete (sm, fs); + vec_free (a->new_segment_indices); + return 0; +} + static int sfifo_test_fifo_segment_slave (int verbose) { @@ -2219,6 +2287,11 @@ sfifo_test_fifo_segment (vlib_main_t * vm, unformat_input_t * input) if ((rv = sfifo_test_fifo_segment_fifo_grow (verbose))) return -1; } + else if (unformat (input, "shrink fifo")) + { + if ((rv = sfifo_test_fifo_segment_fifo_shrink (verbose))) + return -1; + } else if (unformat (input, "all")) { if ((rv = sfifo_test_fifo_segment_hello_world (verbose))) @@ -2227,6 +2300,8 @@ sfifo_test_fifo_segment (vlib_main_t * vm, unformat_input_t * input) return -1; if ((rv = sfifo_test_fifo_segment_fifo_grow (verbose))) return -1; + if ((rv = sfifo_test_fifo_segment_fifo_shrink (verbose))) + return -1; /* Pretty slow so avoid running it always if ((rv = sfifo_test_fifo_segment_master_slave (verbose))) return -1; diff --git a/src/svm/fifo_segment.c b/src/svm/fifo_segment.c index 9c332d6f1fa..0263d1a57cc 100644 --- a/src/svm/fifo_segment.c +++ b/src/svm/fifo_segment.c @@ -570,6 +570,35 @@ fifo_segment_grow_fifo (fifo_segment_t * fs, svm_fifo_t * f, u32 chunk_size) return 0; } +int +fifo_segment_collect_fifo_chunks (fifo_segment_t * fs, svm_fifo_t * f) +{ + svm_fifo_chunk_t *cur, *next; + ssvm_shared_header_t *sh; + void *oldheap; + int fl_index; + + sh = fs->ssvm.sh; + ssvm_lock_non_recursive (sh, 1); + + oldheap = ssvm_push_heap (sh); + cur = svm_fifo_collect_chunks (f); + + while (cur) + { + next = cur->next; + fl_index = fs_free_list_for_size (cur->length); + cur->next = fs->h->free_chunks[fl_index]; + fs->h->free_chunks[fl_index] = cur; + cur = next; + } + + ssvm_pop_heap (oldheap); + ssvm_unlock_non_recursive (sh); + + return 0; +} + /** * Get number of active fifos */ diff --git a/src/svm/fifo_segment.h b/src/svm/fifo_segment.h index 6ff538fcc07..bb4f4080502 100644 --- a/src/svm/fifo_segment.h +++ b/src/svm/fifo_segment.h @@ -128,6 +128,15 @@ void fifo_segment_preallocate_fifo_pairs (fifo_segment_t * fs, */ int fifo_segment_grow_fifo (fifo_segment_t * fs, svm_fifo_t * f, u32 chunk_size); + +/** + * Collect unused chunks for fifo + * + * @param fs fifo segment for fifo + * @param f fifo whose chunks are to be collected + * @return 0 on success, error otherwise + */ +int fifo_segment_collect_fifo_chunks (fifo_segment_t * fs, svm_fifo_t * f); u8 fifo_segment_has_fifos (fifo_segment_t * fs); svm_fifo_t *fifo_segment_get_fifo_list (fifo_segment_t * fs); u32 fifo_segment_num_fifos (fifo_segment_t * fs); diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index e017b619d15..3824d998866 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -677,7 +677,10 @@ svm_fifo_reduce_size (svm_fifo_t * f, u32 len, u8 try_shrink) svm_fifo_chunk_t *cur; u32 actual_len = 0; - if (len > f->nitems) + /* Abort if trying to reduce by more than fifo size or if + * fifo is undergoing resizing already */ + if (len >= f->size || f->size > f->nitems + 1 + || (f->flags & SVM_FIFO_F_SHRINK) || (f->flags & SVM_FIFO_F_GROW)) return 0; /* last chunk that will not be removed */ diff --git a/src/vnet/session/segment_manager.c b/src/vnet/session/segment_manager.c index 9a8af3b42fc..6213cd517f6 100644 --- a/src/vnet/session/segment_manager.c +++ b/src/vnet/session/segment_manager.c @@ -682,6 +682,37 @@ segment_manager_grow_fifo (segment_manager_t * sm, svm_fifo_t * f, u32 size) return rv; } +int +segment_manager_collect_fifo_chunks (segment_manager_t * sm, svm_fifo_t * f) +{ + fifo_segment_t *fs; + int rv; + + fs = segment_manager_get_segment_w_lock (sm, f->segment_index); + rv = fifo_segment_collect_fifo_chunks (fs, f); + segment_manager_segment_reader_unlock (sm); + + return rv; +} + +int +segment_manager_shrink_fifo (segment_manager_t * sm, svm_fifo_t * f, u32 size, + u8 is_producer) +{ + int rv; + + rv = svm_fifo_reduce_size (f, size, is_producer); + + /* Nothing to collect at this point */ + if (!is_producer) + return rv; + + if (f->flags & SVM_FIFO_F_COLLECT_CHUNKS) + segment_manager_collect_fifo_chunks (sm, f); + + return rv; +} + u32 segment_manager_evt_q_expected_size (u32 q_len) { diff --git a/src/vnet/session/segment_manager.h b/src/vnet/session/segment_manager.h index cbf8e353522..8358c50ba06 100644 --- a/src/vnet/session/segment_manager.h +++ b/src/vnet/session/segment_manager.h @@ -125,6 +125,40 @@ void segment_manager_dealloc_fifos (svm_fifo_t * rx_fifo, */ int segment_manager_grow_fifo (segment_manager_t * sm, svm_fifo_t * f, u32 size); + +/** + * Request to shrink fifo owned by segment manager + * + * If this is not called by the producer, no attempt is made to reduce the + * size until the producer tries to enqueue more data. To collect the chunks + * that are to be removed call @ref segment_manager_collect_fifo_chunks + * + * Size reduction does not affect fifo chunk boundaries. Therefore chunks are + * not split and the amount of bytes to be removed can be equal to or less + * than what was requested. + * + * @param sm segment manager that owns the fifo + * @param f fifo to be shrunk + * @param size amount of bytes to remove from fifo + * @param is_producer flag that indicates is caller is the producer for the + * fifo. + * @return actual number of bytes to be removed + */ +int segment_manager_shrink_fifo (segment_manager_t * sm, svm_fifo_t * f, + u32 size, u8 is_producer); + +/** + * Collect fifo chunks that are no longer used + * + * This should not be called unless SVM_FIFO_F_COLLECT_CHUNKS is set for + * the fifo. The chunks are returned to the fifo segment freelist. + * + * @param sm segment manager that owns the fifo + * @param f fifo whose chunks are to be collected + * @return 0 on success, error otherwise + */ +int segment_manager_collect_fifo_chunks (segment_manager_t * sm, + svm_fifo_t * f); u8 segment_manager_has_fifos (segment_manager_t * sm); svm_msg_q_t *segment_manager_alloc_queue (fifo_segment_t * fs, -- 2.16.6