diff options
Diffstat (limited to 'src/svm')
| -rw-r--r-- | src/svm/svm_fifo.c | 126 | ||||
| -rw-r--r-- | src/svm/svm_fifo.h | 21 |
2 files changed, 109 insertions, 38 deletions
diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index 097bab77..bd968aea 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -15,6 +15,36 @@ #include <svm/svm_fifo.h> +#define offset_lt(_a, _b) ((i32)((_a)-(_b)) < 0) +#define offset_leq(_a, _b) ((i32)((_a)-(_b)) <= 0) + +u8 * +format_ooo_segment (u8 * s, va_list * args) +{ + ooo_segment_t *seg = va_arg (*args, ooo_segment_t *); + + s = format (s, "pos %u, len %u, next %d, prev %d", + seg->start, seg->length, seg->next, seg->prev); + return s; +} + +u8 * +format_ooo_list (u8 * s, va_list * args) +{ + svm_fifo_t *f = va_arg (*args, svm_fifo_t *); + u32 ooo_segment_index = f->ooos_list_head; + ooo_segment_t *seg; + + while (ooo_segment_index != OOO_SEGMENT_INVALID_INDEX) + { + seg = pool_elt_at_index (f->ooo_segments, ooo_segment_index); + s = format (s, "\n %U", format_ooo_segment, seg); + + ooo_segment_index = seg->next; + } + return s; +} + /** create an svm fifo, in the current heap. Fails vs blow up the process */ svm_fifo_t * svm_fifo_create (u32 data_size_in_bytes) @@ -47,7 +77,7 @@ ooo_segment_new (svm_fifo_t * f, u32 start, u32 length) pool_get (f->ooo_segments, s); - s->fifo_position = start; + s->start = start; s->length = length; s->prev = s->next = OOO_SEGMENT_INVALID_INDEX; @@ -88,14 +118,13 @@ static void ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) { ooo_segment_t *s, *new_s, *prev, *next, *it; - u32 new_index, position, end_offset, s_sof, s_eof, s_index; + u32 new_index, end_offset, s_sof, s_eof, s_index; - position = (f->tail + offset) % f->nitems; end_offset = offset + length; if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX) { - s = ooo_segment_new (f, position, length); + s = ooo_segment_new (f, offset, length); f->ooos_list_head = s - f->ooo_segments; f->ooos_newest = f->ooos_list_head; return; @@ -104,26 +133,26 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) /* Find first segment that starts after new segment */ s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head); while (s->next != OOO_SEGMENT_INVALID_INDEX - && ooo_segment_offset (f, s) <= offset) + && offset_leq (ooo_segment_offset (f, s), offset)) s = pool_elt_at_index (f->ooo_segments, s->next); s_index = s - f->ooo_segments; s_sof = ooo_segment_offset (f, s); s_eof = ooo_segment_end_offset (f, s); + prev = ooo_segment_get_prev (f, s); /* No overlap, add before current segment */ - if (end_offset < s_sof) + if (offset_lt (end_offset, s_sof) + && (!prev || offset_lt (prev->start + prev->length, offset))) { - new_s = ooo_segment_new (f, position, length); + new_s = ooo_segment_new (f, offset, length); new_index = new_s - f->ooo_segments; /* Pool might've moved, get segment again */ s = pool_elt_at_index (f->ooo_segments, s_index); - if (s->prev != OOO_SEGMENT_INVALID_INDEX) { new_s->prev = s->prev; - prev = pool_elt_at_index (f->ooo_segments, new_s->prev); prev->next = new_index; } @@ -139,9 +168,9 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) return; } /* No overlap, add after current segment */ - else if (s_eof < offset) + else if (offset_lt (s_eof, offset)) { - new_s = ooo_segment_new (f, position, length); + new_s = ooo_segment_new (f, offset, length); new_index = new_s - f->ooo_segments; /* Pool might've moved, get segment again */ @@ -150,7 +179,6 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) if (s->next != OOO_SEGMENT_INVALID_INDEX) { new_s->next = s->next; - next = pool_elt_at_index (f->ooo_segments, new_s->next); next->prev = new_index; } @@ -167,7 +195,7 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) */ /* Merge at head */ - if (offset <= s_sof) + if (offset_leq (offset, s_sof)) { /* If we have a previous, check if we overlap */ if (s->prev != OOO_SEGMENT_INVALID_INDEX) @@ -176,26 +204,31 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) /* New segment merges prev and current. Remove previous and * update position of current. */ - if (ooo_segment_end_offset (f, prev) >= offset) + if (offset_leq (offset, ooo_segment_end_offset (f, prev))) { - s->fifo_position = prev->fifo_position; + s->start = prev->start; s->length = s_eof - ooo_segment_offset (f, prev); ooo_segment_del (f, s->prev); } + else + { + s->start = offset; + s->length = s_eof - ooo_segment_offset (f, s); + } } else { - s->fifo_position = position; + s->start = offset; s->length = s_eof - ooo_segment_offset (f, s); } /* The new segment's tail may cover multiple smaller ones */ - if (s_eof < end_offset) + if (offset_lt (s_eof, end_offset)) { /* Remove segments completely covered */ it = (s->next != OOO_SEGMENT_INVALID_INDEX) ? pool_elt_at_index (f->ooo_segments, s->next) : 0; - while (it && ooo_segment_end_offset (f, it) < end_offset) + while (it && offset_lt (ooo_segment_end_offset (f, it), end_offset)) { next = (it->next != OOO_SEGMENT_INVALID_INDEX) ? pool_elt_at_index (f->ooo_segments, it->next) : 0; @@ -207,7 +240,7 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) s->length = end_offset - ooo_segment_offset (f, s); /* If partial overlap with last, merge */ - if (it && ooo_segment_offset (f, it) < end_offset) + if (it && offset_lt (ooo_segment_offset (f, it), end_offset)) { s->length += it->length - (ooo_segment_offset (f, it) - end_offset); @@ -216,7 +249,7 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) } } /* Last but overlapping previous */ - else if (s_eof <= end_offset) + else if (offset_leq (s_eof, end_offset)) { s->length = end_offset - ooo_segment_offset (f, s); } @@ -247,7 +280,7 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head); /* If last tail update overlaps one/multiple ooo segments, remove them */ - diff = (f->nitems + f->tail - s->fifo_position) % f->nitems; + diff = (f->nitems + ((int) s->start - f->tail)) % f->nitems; while (0 < diff && diff < n_bytes_enqueued) { /* Segment end is beyond the tail. Advance tail and be done */ @@ -262,7 +295,7 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) { index = s - f->ooo_segments; s = pool_elt_at_index (f->ooo_segments, s->next); - diff = (f->nitems + f->tail - s->fifo_position) % f->nitems; + diff = (f->nitems + ((int) s->start - f->tail)) % f->nitems; ooo_segment_del (f, index); } /* End of search */ @@ -368,9 +401,20 @@ svm_fifo_enqueue_with_offset_internal (svm_fifo_t * f, { u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; u32 cursize, nitems; - u32 tail_plus_offset; + u32 normalized_offset; + int rv; - ASSERT (offset > 0); + /* Safety: don't wrap more than nitems/2 */ + ASSERT ((f->nitems + offset - f->tail) % f->nitems < f->nitems / 2); + + /* Users would do do well to avoid this */ + if (PREDICT_FALSE (f->tail == (offset % f->nitems))) + { + rv = svm_fifo_enqueue_internal (f, pid, required_bytes, copy_from_here); + if (rv > 0) + return 0; + return -1; + } /* read cursize, which can only increase while we're working */ cursize = svm_fifo_max_dequeue (f); @@ -384,24 +428,24 @@ svm_fifo_enqueue_with_offset_internal (svm_fifo_t * f, /* Number of bytes we're going to copy */ total_copy_bytes = required_bytes; - tail_plus_offset = (f->tail + offset) % nitems; + normalized_offset = offset % nitems; /* Number of bytes in first copy segment */ - first_copy_bytes = ((nitems - tail_plus_offset) < total_copy_bytes) - ? (nitems - tail_plus_offset) : total_copy_bytes; + first_copy_bytes = ((nitems - normalized_offset) < total_copy_bytes) + ? (nitems - normalized_offset) : total_copy_bytes; - clib_memcpy (&f->data[tail_plus_offset], copy_from_here, first_copy_bytes); + clib_memcpy (&f->data[normalized_offset], copy_from_here, first_copy_bytes); /* Number of bytes in second copy segment, if any */ second_copy_bytes = total_copy_bytes - first_copy_bytes; if (second_copy_bytes) { - tail_plus_offset += first_copy_bytes; - tail_plus_offset %= nitems; + normalized_offset += first_copy_bytes; + normalized_offset %= nitems; - ASSERT (tail_plus_offset == 0); + ASSERT (normalized_offset == 0); - clib_memcpy (&f->data[tail_plus_offset], + clib_memcpy (&f->data[normalized_offset], copy_from_here + first_copy_bytes, second_copy_bytes); } @@ -573,8 +617,8 @@ format_svm_fifo (u8 * s, va_list * args) ooo_segment_t *seg; u32 seg_index; - s = - format (s, "ooo pool %d active elts\n", pool_elts (f->ooo_segments)); + s = format (s, "ooo pool %d active elts\n", + pool_elts (f->ooo_segments)); seg_index = f->ooos_list_head; @@ -582,13 +626,25 @@ format_svm_fifo (u8 * s, va_list * args) { seg = pool_elt_at_index (f->ooo_segments, seg_index); s = format (s, " pos %u, len %u next %d\n", - seg->fifo_position, seg->length, seg->next); + seg->start, seg->length, seg->next); seg_index = seg->next; } } return s; } +u32 +svm_fifo_number_ooo_segments (svm_fifo_t * f) +{ + return pool_elts (f->ooo_segments); +} + +ooo_segment_t * +svm_fifo_first_ooo_segment (svm_fifo_t * f) +{ + return pool_elt_at_index (f->ooo_segments, f->ooos_list_head); +} + /* * fd.io coding-style-patch-verification: ON * diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h index 9beb63f5..0fff2577 100644 --- a/src/svm/svm_fifo.h +++ b/src/svm/svm_fifo.h @@ -36,10 +36,13 @@ typedef struct u32 next; /**< Next linked-list element pool index */ u32 prev; /**< Previous linked-list element pool index */ - u32 fifo_position; /**< Start of segment, normalized*/ + u32 start; /**< Start of segment, normalized*/ u32 length; /**< Length of segment */ } ooo_segment_t; +format_function_t format_ooo_segment; +format_function_t format_ooo_list; + #define OOO_SEGMENT_INVALID_INDEX ((u32)~0) typedef struct @@ -127,6 +130,8 @@ int svm_fifo_dequeue_nowait (svm_fifo_t * f, int pid, u32 max_bytes, int svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes, u8 * copy_here); int svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes); +u32 svm_fifo_number_ooo_segments (svm_fifo_t * f); +ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f); format_function_t format_svm_fifo; @@ -139,13 +144,23 @@ svm_fifo_newest_ooo_segment (svm_fifo_t * f) always_inline u32 ooo_segment_offset (svm_fifo_t * f, ooo_segment_t * s) { - return ((f->nitems + s->fifo_position - f->tail) % f->nitems); +// return ((f->nitems + s->fifo_position - f->tail) % f->nitems); + return s->start; } always_inline u32 ooo_segment_end_offset (svm_fifo_t * f, ooo_segment_t * s) { - return ((f->nitems + s->fifo_position + s->length - f->tail) % f->nitems); +// return ((f->nitems + s->fifo_position + s->length - f->tail) % f->nitems); + return s->start + s->length; +} + +always_inline ooo_segment_t * +ooo_segment_get_prev (svm_fifo_t * f, ooo_segment_t * s) +{ + if (s->prev == OOO_SEGMENT_INVALID_INDEX) + return 0; + return pool_elt_at_index (f->ooo_segments, s->prev); } #endif /* __included_ssvm_fifo_h__ */ |