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-rw-r--r--src/plugins/unittest/svm_fifo_test.c400
-rw-r--r--src/svm/svm_fifo.c262
-rw-r--r--src/svm/svm_fifo.h79
3 files changed, 663 insertions, 78 deletions
diff --git a/src/plugins/unittest/svm_fifo_test.c b/src/plugins/unittest/svm_fifo_test.c
index d2afc36e0d0..7d83b105c93 100644
--- a/src/plugins/unittest/svm_fifo_test.c
+++ b/src/plugins/unittest/svm_fifo_test.c
@@ -1456,8 +1456,403 @@ cleanup:
}
svm_fifo_free (f);
+ vec_free (test_data);
+ vec_free (data_buf);
+ return 0;
+}
+
+static int
+chunk_list_len (svm_fifo_chunk_t * c)
+{
+ svm_fifo_chunk_t *it;
+ int count = 0;
+
+ if (!c)
+ return 0;
+
+ count = 1;
+ it = c->next;
+ while (it && it != c)
+ {
+ it = it->next;
+ count++;
+ }
+ return count;
+}
+
+static void
+chunk_list_free (svm_fifo_chunk_t * c, svm_fifo_chunk_t * stop)
+{
+ svm_fifo_chunk_t *it, *next;
+
+ it = c;
+ while (it && it != stop)
+ {
+ next = it->next;
+ clib_mem_free (it);
+ it = next;
+ }
+}
+
+static void
+chunk_list_splice (svm_fifo_chunk_t * a, svm_fifo_chunk_t * b)
+{
+ svm_fifo_chunk_t *it;
+
+ it = a;
+ while (it->next)
+ it = it->next;
+ it->next = b;
+}
+
+static int
+sfifo_test_fifo_shrink (vlib_main_t * vm, unformat_input_t * input)
+{
+ int __clib_unused verbose = 0, fifo_size = 101, chunk_size = 100;
+ int i, rv, test_n_bytes, diff, deq_bytes;
+ svm_fifo_chunk_t *c, *prev, *collected;
+ u8 *test_data = 0, *data_buf = 0;
+ svm_fifo_t *f;
+ while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+ {
+ if (unformat (input, "verbose"))
+ verbose = 1;
+ else
+ {
+ vlib_cli_output (vm, "parse error: '%U'", format_unformat_error,
+ input);
+ return -1;
+ }
+ }
+
+ /*
+ * Init fifo with multiple chunks
+ */
+ f = fifo_prepare (fifo_size);
+ svm_fifo_init_pointers (f, 0, 0);
+
+ prev = 0;
+ for (i = 0; i < 11; i++)
+ {
+ c = clib_mem_alloc (sizeof (svm_fifo_chunk_t) + chunk_size);
+ c->length = 100;
+ c->start_byte = ~0;
+ c->next = prev;
+ prev = c;
+ }
+
+ svm_fifo_add_chunk (f, c);
+ SFIFO_TEST (f->size == 12 * chunk_size + 1, "size expected %u is %u",
+ 12 * chunk_size + 1, f->size);
+
+ /*
+ * No fifo wrap and no chunk used (one chunk)
+ */
+ rv = svm_fifo_reduce_size (f, chunk_size, 0);
+ SFIFO_TEST (rv == chunk_size, "len expected %u is %u", chunk_size, rv);
+ SFIFO_TEST (f->size == 12 * chunk_size + 1, "size expected %u is %u",
+ 12 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+
+ /* Check enqueue space to force size reduction */
+ (void) svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_COLLECT_CHUNKS, "collect flag should"
+ " be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_SHRINK), "shrink flag should not be"
+ " set");
+
+ collected = c = svm_fifo_collect_chunks (f);
+ rv = chunk_list_len (c);
+ SFIFO_TEST (rv == 1, "expected %u chunks got %u", 1, rv);
+ rv = chunk_list_len (f->start_chunk);
+ SFIFO_TEST (rv == 11, "expected %u chunks got %u", 11, rv);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /*
+ * Fifo wrap and multiple chunks used
+ */
+
+ /* Init test data and fifo */
+ test_n_bytes = f->nitems;
+ vec_validate (test_data, test_n_bytes - 1);
+ vec_validate (data_buf, vec_len (test_data));
+
+ for (i = 0; i < vec_len (test_data); i++)
+ test_data[i] = i;
+
+ svm_fifo_init_pointers (f, f->size / 2, f->size / 2);
+ for (i = 0; i < test_n_bytes; i++)
+ {
+ rv = svm_fifo_enqueue (f, sizeof (u8), &test_data[i]);
+ if (rv < 0)
+ SFIFO_TEST (0, "enqueue returned");
+ }
+
+ /* Try to reduce fifo size with fifo full */
+ rv = svm_fifo_reduce_size (f, 3.5 * chunk_size, 0);
+ SFIFO_TEST (rv == 3 * chunk_size, "len expected %u is %u", 3 * chunk_size,
+ rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+
+ /* Check enqueue space to try size reduction. Should not work */
+ rv = svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (rv == 0, "free space expected %u is %u", 0, rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /* Dequeue byte-by-byte up to last byte on last chunk */
+ deq_bytes = f->size - f->size / 2 - 1;
+ for (i = 0; i < deq_bytes; i++)
+ {
+ (void) svm_fifo_max_enqueue (f);
+ rv = svm_fifo_dequeue (f, 1, &data_buf[i]);
+ if (rv < 0)
+ SFIFO_TEST (0, "dequeue returned");
+ }
+
+ rv = svm_fifo_max_enqueue (f);
+
+ /* We've dequeued more than 3*chunk_size so nitems should be updated */
+ SFIFO_TEST (f->nitems == 8 * chunk_size, "nitems expected %u is %u",
+ 8 * chunk_size, f->nitems);
+ /* Free space should be what was dequeued - 3 * chunk_size, which was
+ * consumed by shrinking the fifo */
+ diff = deq_bytes - 3 * chunk_size;
+ SFIFO_TEST (rv == diff, "free space expected %u is %u", diff, rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /* Dequeue one more such that head goes beyond last chunk */
+ rv = svm_fifo_dequeue (f, 1, &data_buf[deq_bytes]);
+ if (rv < 0)
+ SFIFO_TEST (0, "dequeue returned");
+
+ rv = svm_fifo_max_enqueue (f);
+ SFIFO_TEST (f->nitems == 8 * chunk_size, "nitems expected %u is %u",
+ 8 * chunk_size, f->nitems);
+ SFIFO_TEST (rv == diff + 1, "free space expected %u is %u", diff + 1, rv);
+ SFIFO_TEST (f->size == 8 * chunk_size + 1, "size expected %u is %u",
+ 8 * chunk_size + 1, f->size);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_SHRINK), "shrink flag should not be"
+ " set");
+ SFIFO_TEST (f->flags & SVM_FIFO_F_COLLECT_CHUNKS, "collect flag should"
+ " be set");
+
+ /* Dequeue the rest of the data */
+ deq_bytes += 1;
+ for (i = 0; i < test_n_bytes - deq_bytes; i++)
+ {
+ rv = svm_fifo_dequeue (f, 1, &data_buf[i + deq_bytes]);
+ if (rv < 0)
+ SFIFO_TEST (0, "dequeue returned");
+ }
+
+ rv = svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (f->size == 8 * chunk_size + 1, "size expected %u is %u",
+ 8 * chunk_size + 1, f->size);
+ SFIFO_TEST (rv == 8 * chunk_size, "free space expected %u is %u",
+ 8 * chunk_size, rv);
+
+ rv = compare_data (data_buf, test_data, 0, vec_len (test_data),
+ (u32 *) & i);
+ if (rv)
+ SFIFO_TEST (0, "[%d] dequeued %u expected %u", i, data_buf[i],
+ test_data[i]);
+
+ c = svm_fifo_collect_chunks (f);
+ rv = chunk_list_len (c);
+ SFIFO_TEST (rv == 3, "expected %u chunks got %u", 3, rv);
+ rv = chunk_list_len (f->start_chunk);
+ SFIFO_TEST (rv == 8, "expected %u chunks got %u", 8, rv);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /*
+ * OOO segment on chunk that should be removed
+ */
+
+ svm_fifo_add_chunk (f, c);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+
+ memset (data_buf, 0, vec_len (data_buf));
+ svm_fifo_init_pointers (f, f->size / 2, f->size / 2);
+ svm_fifo_enqueue (f, 200, test_data);
+ svm_fifo_enqueue_with_offset (f, 50, vec_len (test_data) - 250,
+ &test_data[250]);
+
+ /* Free space */
+ rv = svm_fifo_max_enqueue (f);
+ SFIFO_TEST (rv == vec_len (test_data) - 200, "free space expected %u is %u",
+ vec_len (test_data) - 200, rv);
+
+ /* Ask to reduce size */
+ rv = svm_fifo_reduce_size (f, 3.5 * chunk_size, 0);
+ SFIFO_TEST (rv == 3 * chunk_size, "len expected %u is %u", 3 * chunk_size,
+ rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+
+ /* Try to force size reduction but it should fail */
+ rv = svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (rv == vec_len (test_data) - 200, "free space expected %u is %u",
+ vec_len (test_data) - 200, rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /* Dequeue the in order data. This should shrink nitems */
+ rv = svm_fifo_dequeue (f, 200, data_buf);
+ if (rv < 0)
+ SFIFO_TEST (0, "dequeue returned");
+
+ rv = svm_fifo_max_enqueue (f);
+ SFIFO_TEST (rv == vec_len (test_data) - 200, "free space expected %u is %u",
+ vec_len (test_data) - 200, rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->nitems == 11 * chunk_size - 200, "nitems expected %u is %u",
+ 11 * chunk_size - 200, f->nitems);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /* Enqueue the missing 50 bytes. Fifo will become full */
+ rv = svm_fifo_enqueue (f, 50, &test_data[200]);
+ SFIFO_TEST (rv == vec_len (test_data) - 200, "free space expected %u is %u",
+ vec_len (test_data) - 200, rv);
+
+ rv = svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (rv == 0, "free space expected %u is %u", 0, rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+
+ /* Dequeue a chunk and check nitems shrink but fifo still full */
+ svm_fifo_dequeue (f, 100, &data_buf[200]);
+
+ rv = svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (rv == 0, "free space expected %u is %u", 0, rv);
+ SFIFO_TEST (f->size == 11 * chunk_size + 1, "size expected %u is %u",
+ 11 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->nitems == 11 * chunk_size - 300, "nitems expected %u is %u",
+ 11 * chunk_size - 300, f->nitems);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ /* Dequeue enough to unwrap the fifo */
+ deq_bytes = f->size - f->size / 2 - 300;
+ svm_fifo_dequeue (f, deq_bytes, &data_buf[300]);
+ rv = svm_fifo_max_enqueue (f);
+
+ /* Overall we've dequeued deq_bytes + 300, but fifo size shrunk 300 */
+ SFIFO_TEST (rv == 300 + deq_bytes - 300, "free space expected %u is %u",
+ 300 + deq_bytes - 300, rv);
+ SFIFO_TEST (f->size == 8 * chunk_size + 1, "size expected %u is %u",
+ 8 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->nitems == 8 * chunk_size, "nitems expected %u is %u",
+ 8 * chunk_size, f->nitems);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_SHRINK), "shrink flag should not be"
+ " set");
+ SFIFO_TEST (f->flags & SVM_FIFO_F_COLLECT_CHUNKS, "collect flag should"
+ " be set");
+
+ /* Dequeue the rest */
+ svm_fifo_dequeue (f, test_n_bytes / 2, &data_buf[300 + deq_bytes]);
+ rv = compare_data (data_buf, test_data, 0, vec_len (test_data),
+ (u32 *) & i);
+ if (rv)
+ SFIFO_TEST (0, "[%d] dequeued %u expected %u", i, data_buf[i],
+ test_data[i]);
+
+ c = svm_fifo_collect_chunks (f);
+ rv = chunk_list_len (c);
+ SFIFO_TEST (rv == 3, "expected %u chunks got %u", 3, rv);
+ rv = chunk_list_len (f->start_chunk);
+ SFIFO_TEST (rv == 8, "expected %u chunks got %u", 8, rv);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ chunk_list_splice (collected, c);
+
+ /*
+ * Remove all chunks possible
+ */
+ svm_fifo_init_pointers (f, 601, 601);
+ rv = svm_fifo_reduce_size (f, 8 * chunk_size, 1);
+ SFIFO_TEST (rv == 7 * chunk_size, "actual len expected %u is %u",
+ 7 * chunk_size, rv);
+ SFIFO_TEST (f->size == 6 * chunk_size + 1, "size expected %u is %u",
+ 6 * chunk_size + 1, f->size);
+ SFIFO_TEST (f->nitems == 1 * chunk_size, "nitems expected %u is %u",
+ 1 * chunk_size, f->nitems);
+ SFIFO_TEST (f->flags & SVM_FIFO_F_SHRINK, "shrink flag should be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+
+ rv = svm_fifo_max_enqueue (f);
+ SFIFO_TEST (rv == chunk_size, "free space expected %u is %u", chunk_size,
+ rv);
+
+ /* Force head/tail to move to first chunk */
+ svm_fifo_enqueue (f, 1, test_data);
+ svm_fifo_dequeue (f, 1, data_buf);
+ rv = svm_fifo_max_enqueue (f);
+
+ SFIFO_TEST (rv == chunk_size, "free space expected %u is %u", chunk_size,
+ rv);
+ SFIFO_TEST (f->size == chunk_size + 1, "size expected %u is %u",
+ chunk_size + 1, f->size);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_SHRINK), "shrink flag should not be"
+ " set");
+ SFIFO_TEST (f->flags & SVM_FIFO_F_COLLECT_CHUNKS, "collect flag should"
+ " be set");
+
+ c = svm_fifo_collect_chunks (f);
+ rv = chunk_list_len (c);
+ SFIFO_TEST (rv == 7, "expected %u chunks got %u", 7, rv);
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_COLLECT_CHUNKS), "collect flag should"
+ " not be set");
+ SFIFO_TEST (!(f->flags & SVM_FIFO_F_MULTI_CHUNK), "multi-chunk flag should"
+ " not be set");
+
+ chunk_list_splice (collected, c);
+
+ /*
+ * Cleanup
+ */
+
+ chunk_list_free (f->start_chunk->next, f->start_chunk);
+ chunk_list_free (collected, 0);
+ svm_fifo_free (f);
+ vec_free (test_data);
vec_free (data_buf);
+
return 0;
}
@@ -1876,6 +2271,8 @@ svm_fifo_test (vlib_main_t * vm, unformat_input_t * input,
res = sfifo_test_fifo_replay (vm, input);
else if (unformat (input, "grow"))
res = sfifo_test_fifo_grow (vm, input);
+ else if (unformat (input, "shrink"))
+ res = sfifo_test_fifo_shrink (vm, input);
else if (unformat (input, "segment"))
res = sfifo_test_fifo_segment (vm, input);
else if (unformat (input, "all"))
@@ -1934,6 +2331,9 @@ svm_fifo_test (vlib_main_t * vm, unformat_input_t * input,
if ((res = sfifo_test_fifo_grow (vm, input)))
goto done;
+ if ((res = sfifo_test_fifo_shrink (vm, input)))
+ goto done;
+
str = "all";
unformat_init_cstring (input, str);
if ((res = sfifo_test_fifo_segment (vm, input)))
diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index d5638777290..e017b619d15 100644
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -135,7 +135,7 @@ svm_fifo_free_ooo_data (svm_fifo_t * f)
}
static inline ooo_segment_t *
-ooo_segment_get_prev (svm_fifo_t * f, ooo_segment_t * s)
+ooo_segment_prev (svm_fifo_t * f, ooo_segment_t * s)
{
if (s->prev == OOO_SEGMENT_INVALID_INDEX)
return 0;
@@ -222,7 +222,7 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length)
s = pool_elt_at_index (f->ooo_segments, s->next);
/* If we have a previous and we overlap it, use it as starting point */
- prev = ooo_segment_get_prev (f, s);
+ prev = ooo_segment_prev (f, s);
if (prev
&& position_leq (f, offset_pos, ooo_segment_end_pos (f, prev), tail))
{
@@ -374,6 +374,20 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail)
return bytes;
}
+static ooo_segment_t *
+ooo_segment_last (svm_fifo_t * f)
+{
+ ooo_segment_t *s;
+
+ if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
+ return 0;
+
+ s = svm_fifo_first_ooo_segment (f);
+ while (s->next != OOO_SEGMENT_INVALID_INDEX)
+ s = pool_elt_at_index (f->ooo_segments, s->next);
+ return s;
+}
+
void
svm_fifo_init (svm_fifo_t * f, u32 size)
{
@@ -434,8 +448,63 @@ svm_fifo_chunk_alloc (u32 size)
return c;
}
+static inline u8
+svm_fifo_chunk_includes_pos (svm_fifo_chunk_t * c, u32 pos)
+{
+ return (pos >= c->start_byte && pos < c->start_byte + c->length);
+}
+
+/**
+ * Find chunk for given byte position
+ *
+ * @param f fifo
+ * @param pos normalized position in fifo
+ *
+ * @return chunk that includes given position or 0
+ */
+static svm_fifo_chunk_t *
+svm_fifo_find_chunk (svm_fifo_t * f, u32 pos)
+{
+ rb_tree_t *rt = &f->chunk_lookup;
+ rb_node_t *cur, *prev;
+ svm_fifo_chunk_t *c;
+
+ cur = rb_node (rt, rt->root);
+ while (pos != cur->key)
+ {
+ prev = cur;
+ if (pos < cur->key)
+ cur = rb_node_left (rt, cur);
+ else
+ cur = rb_node_right (rt, cur);
+
+ if (rb_node_is_tnil (rt, cur))
+ {
+ /* Hit tnil as a left child. Find predecessor */
+ if (pos < prev->key)
+ {
+ cur = rb_tree_predecessor (rt, prev);
+ c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
+ if (svm_fifo_chunk_includes_pos (c, pos))
+ return c;
+ return 0;
+ }
+ /* Hit tnil as a right child. Check if this is the one */
+ c = uword_to_pointer (prev->opaque, svm_fifo_chunk_t *);
+ if (svm_fifo_chunk_includes_pos (c, pos))
+ return c;
+
+ return 0;
+ }
+ }
+
+ if (!rb_node_is_tnil (rt, cur))
+ return uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
+ return 0;
+}
+
static inline void
-svm_fifo_size_update (svm_fifo_t * f, svm_fifo_chunk_t * c)
+svm_fifo_grow (svm_fifo_t * f, svm_fifo_chunk_t * c)
{
svm_fifo_chunk_t *prev;
u32 add_bytes = 0;
@@ -458,13 +527,13 @@ svm_fifo_size_update (svm_fifo_t * f, svm_fifo_chunk_t * c)
}
static void
-svm_fifo_try_size_update (svm_fifo_t * f, u32 new_head)
+svm_fifo_try_grow (svm_fifo_t * f, u32 new_head)
{
if (new_head > f->tail)
return;
- svm_fifo_size_update (f, f->new_chunks);
- f->flags &= ~SVM_FIFO_F_SIZE_UPDATE;
+ svm_fifo_grow (f, f->new_chunks);
+ f->flags &= ~SVM_FIFO_F_GROW;
}
void
@@ -472,7 +541,8 @@ svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c)
{
svm_fifo_chunk_t *cur, *prev;
- /* Initialize rbtree if needed and add default chunk to it */
+ /* Initialize rbtree if needed and add default chunk to it. Expectation is
+ * that this is called with the heap where the rbtree's pool is pushed. */
if (!(f->flags & SVM_FIFO_F_MULTI_CHUNK))
{
rb_tree_init (&f->chunk_lookup);
@@ -480,8 +550,7 @@ svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c)
f->flags |= SVM_FIFO_F_MULTI_CHUNK;
}
- /* Initialize chunks and add to lookup rbtree. Expectation is that this is
- * called with the heap where the rbtree's pool is pushed. */
+ /* Initialize chunks and add to lookup rbtree */
cur = c;
if (f->new_chunks)
{
@@ -506,7 +575,7 @@ svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c)
if (!svm_fifo_is_wrapped (f))
{
ASSERT (!f->new_chunks);
- svm_fifo_size_update (f, c);
+ svm_fifo_grow (f, c);
return;
}
@@ -514,63 +583,129 @@ svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c)
if (!f->new_chunks)
{
f->new_chunks = c;
- f->flags |= SVM_FIFO_F_SIZE_UPDATE;
+ f->flags |= SVM_FIFO_F_GROW;
}
}
-static inline u8
-svm_fifo_chunk_includes_pos (svm_fifo_chunk_t * c, u32 pos)
+/**
+ * Removes chunks that are after fifo end byte
+ */
+svm_fifo_chunk_t *
+svm_fifo_collect_chunks (svm_fifo_t * f)
{
- return (pos >= c->start_byte && pos < c->start_byte + c->length);
+ svm_fifo_chunk_t *list, *cur;
+
+ f->flags &= ~SVM_FIFO_F_COLLECT_CHUNKS;
+
+ list = f->new_chunks;
+ f->new_chunks = 0;
+ cur = list;
+ while (cur)
+ {
+ rb_tree_del (&f->chunk_lookup, cur->start_byte);
+ cur = cur->next;
+ }
+
+ return list;
+}
+
+void
+svm_fifo_try_shrink (svm_fifo_t * f, u32 head, u32 tail)
+{
+ u32 len_to_shrink = 0, tail_pos, len;
+ svm_fifo_chunk_t *cur, *prev, *next, *start;
+
+ tail_pos = tail;
+ if (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX)
+ {
+ ooo_segment_t *last = ooo_segment_last (f);
+ tail_pos = ooo_segment_end_pos (f, last);
+ }
+
+ if (f->size_decrement)
+ {
+ /* Figure out available free space considering that there may be
+ * ooo segments */
+ len = clib_min (f->size_decrement, f_free_count (f, head, tail_pos));
+ f->nitems -= len;
+ f->size_decrement -= len;
+ }
+
+ /* Remove tail chunks if the following hold:
+ * - not wrapped
+ * - last used byte less than start of last chunk
+ */
+ if (tail_pos >= head && tail_pos <= f->end_chunk->start_byte)
+ {
+ /* Lookup the last position not to be removed. Since size still needs
+ * to be nitems + 1, nitems must fall within the usable space */
+ tail_pos = tail_pos > 0 ? tail_pos - 1 : tail_pos;
+ prev = svm_fifo_find_chunk (f, clib_max (f->nitems, tail_pos));
+ next = prev->next;
+ while (next != f->start_chunk)
+ {
+ cur = next;
+ next = cur->next;
+ len_to_shrink += cur->length;
+ }
+ if (len_to_shrink)
+ {
+ f->size -= len_to_shrink;
+ start = prev->next;
+ prev->next = f->start_chunk;
+ f->end_chunk = prev;
+ cur->next = f->new_chunks;
+ f->new_chunks = start;
+ }
+ }
+
+ if (!f->size_decrement && f->size == f->nitems + 1)
+ {
+ f->flags &= ~SVM_FIFO_F_SHRINK;
+ f->flags |= SVM_FIFO_F_COLLECT_CHUNKS;
+ if (f->start_chunk == f->start_chunk->next)
+ f->flags &= ~SVM_FIFO_F_MULTI_CHUNK;
+ }
}
/**
- * Find chunk for given byte position
- *
- * @param f fifo
- * @param pos normalized position in fifo
- *
- * @return chunk that includes given position or 0
+ * Request to reduce fifo size by amount of bytes
*/
-static svm_fifo_chunk_t *
-svm_fifo_find_chunk (svm_fifo_t * f, u32 pos)
+int
+svm_fifo_reduce_size (svm_fifo_t * f, u32 len, u8 try_shrink)
{
- rb_tree_t *rt = &f->chunk_lookup;
- rb_node_t *cur, *prev;
- svm_fifo_chunk_t *c;
+ svm_fifo_chunk_t *cur;
+ u32 actual_len = 0;
- cur = rb_node (rt, rt->root);
- while (pos != cur->key)
+ if (len > f->nitems)
+ return 0;
+
+ /* last chunk that will not be removed */
+ cur = svm_fifo_find_chunk (f, f->nitems - len);
+
+ /* sum length of chunks that will be removed */
+ cur = cur->next;
+ while (cur != f->start_chunk)
{
- prev = cur;
- if (pos < cur->key)
- cur = rb_node_left (rt, cur);
- else
- cur = rb_node_right (rt, cur);
+ actual_len += cur->length;
+ cur = cur->next;
+ }
- if (rb_node_is_tnil (rt, cur))
- {
- /* Hit tnil as a left child. Find predecessor */
- if (pos < prev->key)
- {
- cur = rb_tree_predecessor (rt, prev);
- c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
- if (svm_fifo_chunk_includes_pos (c, pos))
- return c;
- return 0;
- }
- /* Hit tnil as a right child. Check if this is the one */
- c = uword_to_pointer (prev->opaque, svm_fifo_chunk_t *);
- if (svm_fifo_chunk_includes_pos (c, pos))
- return c;
+ ASSERT (actual_len <= len);
+ if (!actual_len)
+ return 0;
- return 0;
- }
+ f->size_decrement = actual_len;
+ f->flags |= SVM_FIFO_F_SHRINK;
+
+ if (try_shrink)
+ {
+ u32 head, tail;
+ f_load_head_tail_prod (f, &head, &tail);
+ svm_fifo_try_shrink (f, head, tail);
}
- if (!rb_node_is_tnil (rt, cur))
- return uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
- return 0;
+ return actual_len;
}
void
@@ -660,6 +795,9 @@ svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src)
f_load_head_tail_prod (f, &head, &tail);
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
+ svm_fifo_try_shrink (f, head, tail);
+
/* free space in fifo can only increase during enqueue: SPSC */
free_count = f_free_count (f, head, tail);
@@ -680,6 +818,22 @@ svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src)
return 0;
}
+/**
+ * Advance tail
+ */
+void
+svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len)
+{
+ u32 tail;
+
+ ASSERT (len <= svm_fifo_max_enqueue_prod (f));
+ /* load-relaxed: producer owned index */
+ tail = f->tail;
+ tail = (tail + len) % f->size;
+ /* store-rel: producer owned index (paired with load-acq in consumer) */
+ clib_atomic_store_rel_n (&f->tail, tail);
+}
+
int
svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst)
{
@@ -697,8 +851,8 @@ svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst)
svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk);
head = (head + len) % f->size;
- if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SIZE_UPDATE))
- svm_fifo_try_size_update (f, head);
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_GROW))
+ svm_fifo_try_grow (f, head);
/* store-rel: consumer owned index (paired with load-acq in producer) */
clib_atomic_store_rel_n (&f->head, head);
diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h
index 390e1170e27..417b0ecb672 100644
--- a/src/svm/svm_fifo.h
+++ b/src/svm/svm_fifo.h
@@ -64,9 +64,11 @@ typedef struct svm_fifo_chunk_
typedef enum svm_fifo_flag_
{
- SVM_FIFO_F_SIZE_UPDATE = 1 << 0,
- SVM_FIFO_F_MULTI_CHUNK = 1 << 1,
- SVM_FIFO_F_LL_TRACKED = 1 << 2,
+ SVM_FIFO_F_MULTI_CHUNK = 1 << 0,
+ SVM_FIFO_F_GROW = 1 << 1,
+ SVM_FIFO_F_SHRINK = 1 << 2,
+ SVM_FIFO_F_COLLECT_CHUNKS = 1 << 3,
+ SVM_FIFO_F_LL_TRACKED = 1 << 4,
} svm_fifo_flag_t;
typedef struct _svm_fifo
@@ -86,12 +88,13 @@ typedef struct _svm_fifo
u32 client_session_index; /**< app session index */
u8 master_thread_index; /**< session layer thread index */
u8 client_thread_index; /**< app worker index */
+ i8 refcnt; /**< reference count */
u32 segment_manager; /**< session layer segment manager index */
u32 segment_index; /**< segment index in segment manager */
u32 freelist_index; /**< aka log2(allocated_size) - const. */
- i8 refcnt; /**< reference count */
struct _svm_fifo *next; /**< next in freelist/active chain */
struct _svm_fifo *prev; /**< prev in active chain */
+ u32 size_decrement; /**< bytes to remove from fifo */
CLIB_CACHE_LINE_ALIGN_MARK (consumer);
u32 head; /**< fifo head position/byte */
@@ -172,7 +175,8 @@ f_load_head_tail_prod (svm_fifo_t * f, u32 * head, u32 * tail)
*head = clib_atomic_load_acq_n (&f->head);
}
-/* Load head and tail independent of producer/consumer role
+/**
+ * Load head and tail independent of producer/consumer role
*
* Internal function.
*/
@@ -230,6 +234,13 @@ f_free_count (svm_fifo_t * f, u32 head, u32 tail)
}
/**
+ * Try to shrink fifo size.
+ *
+ * Internal function.
+ */
+void svm_fifo_try_shrink (svm_fifo_t * f, u32 head, u32 tail);
+
+/**
* Create fifo of requested size
*
* Allocates fifo on current heap.
@@ -267,6 +278,31 @@ svm_fifo_chunk_t *svm_fifo_chunk_alloc (u32 size);
*/
void svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c);
/**
+ * Request to reduce fifo size by amount of bytes
+ *
+ * Because the producer might be enqueuing data when this is called, the
+ * actual size update is only applied when producer tries to enqueue new
+ * data, unless @param try_shrink is set.
+ *
+ * @param f fifo
+ * @param len number of bytes to remove from fifo. The actual number
+ * of bytes to be removed will be less or equal to this
+ * value.
+ * @param try_shrink flg to indicate if it's safe to try to shrink fifo
+ * size. It should be set only if this is called by the
+ * producer of if the producer is not using the fifo
+ * @return actual length fifo size will be reduced by
+ */
+int svm_fifo_reduce_size (svm_fifo_t * f, u32 len, u8 try_shrink);
+/**
+ * Removes chunks that are after fifo end byte
+ *
+ * Needs to be called with segment heap pushed.
+ *
+ * @param f fifo
+ */
+svm_fifo_chunk_t *svm_fifo_collect_chunks (svm_fifo_t * f);
+/**
* Free fifo and associated state
*
* @param f fifo
@@ -333,6 +369,16 @@ int svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src);
*/
int svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len,
u8 * src);
+
+/**
+ * Advance tail pointer
+ *
+ * Useful for moving tail pointer after external enqueue.
+ *
+ * @param f fifo
+ * @param len number of bytes to add to tail
+ */
+void svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len);
/**
* Overwrite fifo head with new data
*
@@ -551,6 +597,8 @@ svm_fifo_max_enqueue_prod (svm_fifo_t * f)
{
u32 head, tail;
f_load_head_tail_prod (f, &head, &tail);
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
+ svm_fifo_try_shrink (f, head, tail);
return f_free_count (f, head, tail);
}
@@ -565,6 +613,8 @@ svm_fifo_max_enqueue (svm_fifo_t * f)
{
u32 head, tail;
f_load_head_tail_all_acq (f, &head, &tail);
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
+ svm_fifo_try_shrink (f, head, tail);
return f_free_count (f, head, tail);
}
@@ -590,25 +640,6 @@ svm_fifo_max_write_chunk (svm_fifo_t * f)
return tail > head ? f->size - tail : f_free_count (f, head, tail);
}
-/**
- * Advance tail pointer
- *
- * Useful for moving tail pointer after external enqueue.
- *
- * @param f fifo
- * @param len number of bytes to add to tail
- */
-static inline void
-svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len)
-{
- ASSERT (len <= svm_fifo_max_enqueue_prod (f));
- /* load-relaxed: producer owned index */
- u32 tail = f->tail;
- tail = (tail + len) % f->size;
- /* store-rel: producer owned index (paired with load-acq in consumer) */
- clib_atomic_store_rel_n (&f->tail, tail);
-}
-
static inline u8 *
svm_fifo_head (svm_fifo_t * f)
{