This patch implements predictable RSS functionality.
Signed-off-by: Vladimir Medvedkin <vladimir.medved...@intel.com>
---
lib/librte_hash/rte_thash.c | 610 ++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 587 insertions(+), 23 deletions(-)
diff --git a/lib/librte_hash/rte_thash.c b/lib/librte_hash/rte_thash.c
index 1325678..c76ceee 100644
--- a/lib/librte_hash/rte_thash.c
+++ b/lib/librte_hash/rte_thash.c
@@ -12,6 +12,45 @@
#include <rte_malloc.h>
#define THASH_NAME_LEN 64
+#define TOEPLITZ_HASH_LEN 32
+
+#define RETA_SZ_MIN 2U
+#define RETA_SZ_MAX 16U
+#define RETA_SZ_IN_RANGE(reta_sz) ((reta_sz >= RETA_SZ_MIN) && \
+ (reta_sz <= RETA_SZ_MAX))
+
+TAILQ_HEAD(rte_thash_list, rte_tailq_entry);
+static struct rte_tailq_elem rte_thash_tailq = {
+ .name = "RTE_THASH",
+};
+EAL_REGISTER_TAILQ(rte_thash_tailq)
+
+/**
+ * Table of some irreducible polinomials over GF(2).
+ * For lfsr they are reperesented in BE bit order, and
+ * x^0 is masked out.
+ * For example, poly x^5 + x^2 + 1 will be represented
+ * as (101001b & 11111b) = 01001b = 0x9
+ */
+static const uint32_t irreducible_poly_table[][4] = {
+ {0, 0, 0, 0}, /** < degree 0 */
+ {1, 1, 1, 1}, /** < degree 1 */
+ {0x3, 0x3, 0x3, 0x3}, /** < degree 2 and so on... */
+ {0x5, 0x3, 0x5, 0x3},
+ {0x9, 0x3, 0x9, 0x3},
+ {0x9, 0x1b, 0xf, 0x5},
+ {0x21, 0x33, 0x1b, 0x2d},
+ {0x41, 0x11, 0x71, 0x9},
+ {0x71, 0xa9, 0xf5, 0x8d},
+ {0x21, 0xd1, 0x69, 0x1d9},
+ {0x81, 0x2c1, 0x3b1, 0x185},
+ {0x201, 0x541, 0x341, 0x461},
+ {0x941, 0x609, 0xe19, 0x45d},
+ {0x1601, 0x1f51, 0x1171, 0x359},
+ {0x2141, 0x2111, 0x2db1, 0x2109},
+ {0x4001, 0x801, 0x101, 0x7301},
+ {0x7781, 0xa011, 0x4211, 0x86d9},
+};
struct thash_lfsr {
uint32_t ref_cnt;
@@ -50,60 +89,585 @@ struct rte_thash_ctx {
uint8_t hash_key[0];
};
+static inline uint32_t
+get_bit_lfsr(struct thash_lfsr *lfsr)
+{
+ uint32_t bit, ret;
+
+ /*
+ * masking the TAP bits defined by the polynomial and
+ * calculating parity
+ */
+ bit = __builtin_popcount(lfsr->state & lfsr->poly) & 0x1;
+ ret = lfsr->state & 0x1;
+ lfsr->state = ((lfsr->state >> 1) | (bit << (lfsr->deg - 1))) &
+ ((1 << lfsr->deg) - 1);
+
+ lfsr->bits_cnt++;
+ return ret;
+}
+
+static inline uint32_t
+get_rev_bit_lfsr(struct thash_lfsr *lfsr)
+{
+ uint32_t bit, ret;
+
+ bit = __builtin_popcount(lfsr->rev_state & lfsr->rev_poly) & 0x1;
+ ret = lfsr->rev_state & (1 << (lfsr->deg - 1));
+ lfsr->rev_state = ((lfsr->rev_state << 1) | bit) &
+ ((1 << lfsr->deg) - 1);
+
+ lfsr->bits_cnt++;
+ return ret;
+}
+
+static inline uint32_t
+thash_get_rand_poly(uint32_t poly_degree)
+{
+ return irreducible_poly_table[poly_degree][rte_rand() %
+ RTE_DIM(irreducible_poly_table[poly_degree])];
+}
+
+static struct thash_lfsr *
+alloc_lfsr(struct rte_thash_ctx *ctx)
+{
+ struct thash_lfsr *lfsr;
+ uint32_t i;
+
+ if (ctx == NULL)
+ return NULL;
+
+ lfsr = rte_zmalloc(NULL, sizeof(struct thash_lfsr), 0);
+ if (lfsr == NULL)
+ return NULL;
+
+ lfsr->deg = ctx->reta_sz_log;
+ lfsr->poly = thash_get_rand_poly(lfsr->deg);
+ do {
+ lfsr->state = rte_rand() & ((1 << lfsr->deg) - 1);
+ } while (lfsr->state == 0);
+ /* init reverse order polynomial */
+ lfsr->rev_poly = (lfsr->poly >> 1) | (1 << (lfsr->deg - 1));
+ /* init proper rev_state*/
+ lfsr->rev_state = lfsr->state;
+ for (i = 0; i <= lfsr->deg; i++)
+ get_rev_bit_lfsr(lfsr);
+
+ /* clear bits_cnt after rev_state was inited */
+ lfsr->bits_cnt = 0;
+ lfsr->ref_cnt = 1;
+
+ return lfsr;
+}
+
+static void
+attach_lfsr(struct rte_thash_subtuple_helper *h, struct thash_lfsr *lfsr)
+{
+ lfsr->ref_cnt++;
+ h->lfsr = lfsr;
+}
+
+static void
+free_lfsr(struct thash_lfsr *lfsr)
+{
+ lfsr->ref_cnt--;
+ if (lfsr->ref_cnt == 0)
+ rte_free(lfsr);
+}
+
struct rte_thash_ctx *
-rte_thash_init_ctx(const char *name __rte_unused,
- uint32_t key_len __rte_unused, uint32_t reta_sz __rte_unused,
- uint8_t *key __rte_unused, uint32_t flags __rte_unused)
+rte_thash_init_ctx(const char *name, uint32_t key_len, uint32_t reta_sz,
+ uint8_t *key, uint32_t flags)
{
+ struct rte_thash_ctx *ctx;
+ struct rte_tailq_entry *te;
+ struct rte_thash_list *thash_list;
+ uint32_t i;
+
+ if ((name == NULL) || (key_len == 0) || !RETA_SZ_IN_RANGE(reta_sz)) {
+ rte_errno = EINVAL;
+ return NULL;
+ }
+
+ thash_list = RTE_TAILQ_CAST(rte_thash_tailq.head, rte_thash_list);
+
+ rte_mcfg_tailq_write_lock();
+
+ /* guarantee there's no existing */
+ TAILQ_FOREACH(te, thash_list, next) {
+ ctx = (struct rte_thash_ctx *)te->data;
+ if (strncmp(name, ctx->name, sizeof(ctx->name)) == 0)
+ break;
+ }
+ ctx = NULL;
+ if (te != NULL) {
+ rte_errno = EEXIST;
+ goto exit;
+ }
+
+ /* allocate tailq entry */
+ te = rte_zmalloc("THASH_TAILQ_ENTRY", sizeof(*te), 0);
+ if (te == NULL) {
+ RTE_LOG(ERR, HASH,
+ "Can not allocate tailq entry for thash context %s\n",
+ name);
+ rte_errno = ENOMEM;
+ goto exit;
+ }
+
+ ctx = rte_zmalloc(NULL, sizeof(struct rte_thash_ctx) + key_len, 0);
+ if (ctx == NULL) {
+ RTE_LOG(ERR, HASH, "thash ctx %s memory allocation failed\n",
+ name);
+ rte_errno = ENOMEM;
+ goto free_te;
+ }
+
+ rte_strlcpy(ctx->name, name, sizeof(ctx->name));
+ ctx->key_len = key_len;
+ ctx->reta_sz_log = reta_sz;
+ LIST_INIT(&ctx->head);
+ ctx->flags = flags;
+
+ if (key)
+ rte_memcpy(ctx->hash_key, key, key_len);
+ else {
+ for (i = 0; i < key_len; i++)
+ ctx->hash_key[i] = rte_rand();
+ }
+
+ te->data = (void *)ctx;
+ TAILQ_INSERT_TAIL(thash_list, te, next);
+
+ rte_mcfg_tailq_write_unlock();
+
+ return ctx;
+free_te:
+ rte_free(te);
+exit:
+ rte_mcfg_tailq_write_unlock();
return NULL;
}
struct rte_thash_ctx *
-rte_thash_find_existing(const char *name __rte_unused)
+rte_thash_find_existing(const char *name)
{
- return NULL;
+ struct rte_thash_ctx *ctx;
+ struct rte_tailq_entry *te;
+ struct rte_thash_list *thash_list;
+
+ thash_list = RTE_TAILQ_CAST(rte_thash_tailq.head, rte_thash_list);
+
+ rte_mcfg_tailq_read_lock();
+ TAILQ_FOREACH(te, thash_list, next) {
+ ctx = (struct rte_thash_ctx *)te->data;
+ if (strncmp(name, ctx->name, sizeof(ctx->name)) == 0)
+ break;
+ }
+
+ rte_mcfg_tailq_read_unlock();
+
+ if (te == NULL) {
+ rte_errno = ENOENT;
+ return NULL;
+ }
+
+ return ctx;
}
void
-rte_thash_free_ctx(struct rte_thash_ctx *ctx __rte_unused)
+rte_thash_free_ctx(struct rte_thash_ctx *ctx)
{
+ struct rte_tailq_entry *te;
+ struct rte_thash_list *thash_list;
+ struct rte_thash_subtuple_helper *ent, *tmp;
+
+ if (ctx == NULL)
+ return;
+
+ thash_list = RTE_TAILQ_CAST(rte_thash_tailq.head, rte_thash_list);
+ rte_mcfg_tailq_write_lock();
+ TAILQ_FOREACH(te, thash_list, next) {
+ if (te->data == (void *)ctx)
+ break;
+ }
+
+ if (te != NULL)
+ TAILQ_REMOVE(thash_list, te, next);
+
+ rte_mcfg_tailq_write_unlock();
+ ent = LIST_FIRST(&(ctx->head));
+ while (ent) {
+ free_lfsr(ent->lfsr);
+ tmp = ent;
+ ent = LIST_NEXT(ent, next);
+ LIST_REMOVE(tmp, next);
+ rte_free(tmp);
+ }
+
+ rte_free(ctx);
+ rte_free(te);
+}
+
+static inline void
+set_bit(uint8_t *ptr, uint32_t bit, uint32_t pos)
+{
+ uint32_t byte_idx = pos / CHAR_BIT;
+ uint32_t bit_idx = (CHAR_BIT - 1) - (pos & (CHAR_BIT - 1));
+ uint8_t tmp;
+
+ tmp = ptr[byte_idx];
+ tmp &= ~(1 << bit_idx);
+ tmp |= bit << bit_idx;
+ ptr[byte_idx] = tmp;
+}
+
+/**
+ * writes m-sequence to the hash_key for range [start, end]
+ * (i.e. including start and end positions)
+ */
+static int
+generate_subkey(struct rte_thash_ctx *ctx, struct thash_lfsr *lfsr,
+ uint32_t start, uint32_t end)
+{
+ uint32_t i;
+ uint32_t req_bits = (start < end) ? (end - start) : (start - end);
+ req_bits++; /* due to incuding end */
+
+ /* check if lfsr overflow period of the m-sequence */
+ if (((lfsr->bits_cnt + req_bits) > (1ULL << lfsr->deg) - 1) &&
+ ((ctx->flags & RTE_THASH_IGNORE_PERIOD_OVERFLOW) !=
+ RTE_THASH_IGNORE_PERIOD_OVERFLOW))
+ return -ENOSPC;
+
+ if (start < end) {
+ /* original direction (from left to right)*/
+ for (i = start; i <= end; i++)
+ set_bit(ctx->hash_key, get_bit_lfsr(lfsr), i);
+
+ } else {
+ /* reverse direction (from right to left) */
+ for (i = end; i >= start; i--)
+ set_bit(ctx->hash_key, get_rev_bit_lfsr(lfsr), i);
+ }
+
+ return 0;
+}
+
+static inline uint32_t
+get_subvalue(struct rte_thash_ctx *ctx, uint32_t offset)
+{
+ uint32_t *tmp, val;
+
+ tmp = (uint32_t *)(&ctx->hash_key[offset >> 3]);
+ val = rte_be_to_cpu_32(*tmp);
+ val >>= (TOEPLITZ_HASH_LEN - ((offset & (CHAR_BIT - 1)) +
+ ctx->reta_sz_log));
+
+ return val & ((1 << ctx->reta_sz_log) - 1);
+}
+
+static inline void
+generate_complement_table(struct rte_thash_ctx *ctx,
+ struct rte_thash_subtuple_helper *h)
+{
+ int i, j, k;
+ uint32_t val;
+ uint32_t start;
+
+ start = h->offset + h->len - (2 * ctx->reta_sz_log - 1);
+
+ for (i = 1; i < (1 << ctx->reta_sz_log); i++) {
+ val = 0;
+ for (j = i; j; j &= (j - 1)) {
+ k = rte_bsf32(j);
+ val ^= get_subvalue(ctx, start - k +
+ ctx->reta_sz_log - 1);
+ }
+ h->compl_table[val] = i;
+ }
+}
+
+static inline int
+insert_before(struct rte_thash_ctx *ctx,
+ struct rte_thash_subtuple_helper *ent,
+ struct rte_thash_subtuple_helper *cur_ent,
+ struct rte_thash_subtuple_helper *next_ent,
+ uint32_t start, uint32_t end, uint32_t range_end)
+{
+ int ret;
+
+ if (end < cur_ent->offset) {
+ ent->lfsr = alloc_lfsr(ctx);
+ if (ent->lfsr == NULL) {
+ rte_free(ent);
+ return -ENOMEM;
+ }
+ /* generate nonoverlapping range [start, end) */
+ ret = generate_subkey(ctx, ent->lfsr, start, end - 1);
+ if (ret != 0) {
+ free_lfsr(ent->lfsr);
+ rte_free(ent);
+ return ret;
+ }
+ } else if ((next_ent != NULL) && (end > next_ent->offset)) {
+ rte_free(ent);
+ return -ENOSPC;
+ }
+ attach_lfsr(ent, cur_ent->lfsr);
+
+ /**
+ * generate partially overlapping range
+ * [start, cur_ent->start) in reverse order
+ */
+ ret = generate_subkey(ctx, ent->lfsr, cur_ent->offset - 1, start);
+ if (ret != 0) {
+ free_lfsr(ent->lfsr);
+ rte_free(ent);
+ return ret;
+ }
+
+ if (end > range_end) {
+ /**
+ * generate partially overlapping range
+ * (range_end, end)
+ */
+ ret = generate_subkey(ctx, ent->lfsr, range_end, end - 1);
+ if (ret != 0) {
+ free_lfsr(ent->lfsr);
+ rte_free(ent);
+ return ret;
+ }
+ }
+
+ LIST_INSERT_BEFORE(cur_ent, ent, next);
+ generate_complement_table(ctx, ent);
+ ctx->subtuples_nb++;
+ return 0;
+}
+
+static inline int
+insert_after(struct rte_thash_ctx *ctx,
+ struct rte_thash_subtuple_helper *ent,
+ struct rte_thash_subtuple_helper *cur_ent,
+ struct rte_thash_subtuple_helper *next_ent,
+ struct rte_thash_subtuple_helper *prev_ent,
+ uint32_t end, uint32_t range_end)
+{
+ int ret;
+
+ if ((next_ent != NULL) && (end > next_ent->offset)) {
+ rte_free(ent);
+ return -EEXIST;
+ }
+
+ attach_lfsr(ent, cur_ent->lfsr);
+ if (end > range_end) {
+ /**
+ * generate partially overlapping range
+ * (range_end, end)
+ */
+ ret = generate_subkey(ctx, ent->lfsr, range_end, end - 1);
+ if (ret != 0) {
+ free_lfsr(ent->lfsr);
+ rte_free(ent);
+ return ret;
+ }
+ }
+
+ LIST_INSERT_AFTER(prev_ent, ent, next);
+ generate_complement_table(ctx, ent);
+ ctx->subtuples_nb++;
+
+ return 0;
}
int
-rte_thash_add_helper(struct rte_thash_ctx *ctx __rte_unused,
- const char *name __rte_unused, uint32_t len __rte_unused,
- uint32_t offset __rte_unused)
+rte_thash_add_helper(struct rte_thash_ctx *ctx, const char *name, uint32_t len,
+ uint32_t offset)
{
+ struct rte_thash_subtuple_helper *ent, *cur_ent, *prev_ent, *next_ent;
+ uint32_t start, end;
+ int ret;
+
+ if ((ctx == NULL) || (name == NULL) || (len < ctx->reta_sz_log) ||
+ ((offset + len + TOEPLITZ_HASH_LEN - 1) >
+ ctx->key_len * CHAR_BIT))
+ return -EINVAL;
+
+ /* Check for existing name*/
+ LIST_FOREACH(cur_ent, &ctx->head, next) {
+ if (strncmp(name, cur_ent->name, sizeof(cur_ent->name)) == 0)
+ return -EEXIST;
+ }
+
+ end = offset + len + TOEPLITZ_HASH_LEN - 1;
+ start = ((ctx->flags & RTE_THASH_MINIMAL_SEQ) ==
+ RTE_THASH_MINIMAL_SEQ) ? (end - (2 * ctx->reta_sz_log - 1)) :
+ offset;
+
+ ent = rte_zmalloc(NULL, sizeof(struct rte_thash_subtuple_helper) +
+ sizeof(uint32_t) * (1 << ctx->reta_sz_log),
+ RTE_CACHE_LINE_SIZE);
+ if (ent == NULL)
+ return -ENOMEM;
+
+ rte_strlcpy(ent->name, name, sizeof(ent->name));
+ ent->offset = start;
+ ent->len = end - start;
+ ent->tuple_offset = offset;
+ ent->tuple_len = len;
+ ent->lsb_msk = (1 << ctx->reta_sz_log) - 1;
+
+ cur_ent = LIST_FIRST(&ctx->head);
+ while (cur_ent) {
+ uint32_t range_end = cur_ent->offset + cur_ent->len;
+ next_ent = LIST_NEXT(cur_ent, next);
+ prev_ent = cur_ent;
+ /* Iterate through overlapping ranges */
+ while ((next_ent != NULL) && (next_ent->offset < range_end)) {
+ range_end = RTE_MAX(next_ent->offset + next_ent->len,
+ range_end);
+ if (start > next_ent->offset)
+ prev_ent = next_ent;
+
+ next_ent = LIST_NEXT(next_ent, next);
+ }
+
+ if (start < cur_ent->offset)
+ return insert_before(ctx, ent, cur_ent, next_ent,
+ start, end, range_end);
+ else if (start < range_end)
+ return insert_after(ctx, ent, cur_ent, next_ent,
+ prev_ent, end, range_end);
+
+ cur_ent = next_ent;
+ continue;
+ }
+
+ ent->lfsr = alloc_lfsr(ctx);
+ if (ent->lfsr == NULL) {
+ rte_free(ent);
+ return -ENOMEM;
+ }
+
+ /* generate nonoverlapping range [start, end) */
+ ret = generate_subkey(ctx, ent->lfsr, start, end - 1);
+ if (ret != 0) {
+ free_lfsr(ent->lfsr);
+ rte_free(ent);
+ return ret;
+ }
+ if (LIST_EMPTY(&ctx->head)) {
+ LIST_INSERT_HEAD(&ctx->head, ent, next);
+ } else {
+ LIST_FOREACH(next_ent, &ctx->head, next)
+ prev_ent = next_ent;
+
+ LIST_INSERT_AFTER(prev_ent, ent, next);
+ }
+ generate_complement_table(ctx, ent);
+ ctx->subtuples_nb++;
+
return 0;
}
struct rte_thash_subtuple_helper *
-rte_thash_get_helper(struct rte_thash_ctx *ctx __rte_unused,
- const char *name __rte_unused)
+rte_thash_get_helper(struct rte_thash_ctx *ctx, const char *name)
{
+ struct rte_thash_subtuple_helper *ent;
+
+ if ((ctx == NULL) || (name == NULL))
+ return NULL;
+
+ LIST_FOREACH(ent, &ctx->head, next) {
+ if (strncmp(name, ent->name, sizeof(ent->name)) == 0)
+ return ent;
+ }
+
return NULL;
}
uint32_t
-rte_thash_get_complement(struct rte_thash_subtuple_helper *h __rte_unused,
- uint32_t hash __rte_unused, uint32_t desired_hash __rte_unused)
+rte_thash_get_complement(struct rte_thash_subtuple_helper *h,
+ uint32_t hash, uint32_t desired_hash)
{
- return 0;
+ return h->compl_table[(hash ^ desired_hash) & h->lsb_msk];
}
const uint8_t *
-rte_thash_get_key(struct rte_thash_ctx *ctx __rte_unused)
+rte_thash_get_key(struct rte_thash_ctx *ctx)
{
- return NULL;
+ return ctx->hash_key;
+}
+
+static inline void
+xor_bit(uint8_t *ptr, uint32_t bit, uint32_t pos)
+{
+ uint32_t byte_idx = pos >> 3;
+ uint32_t bit_idx = (CHAR_BIT - 1) - (pos & (CHAR_BIT - 1));
+ uint8_t tmp;
+
+ tmp = ptr[byte_idx];
+ tmp ^= bit << bit_idx;
+ ptr[byte_idx] = tmp;
}
int
-rte_thash_adjust_tuple(struct rte_thash_ctx *ctx __rte_unused,
- struct rte_thash_subtuple_helper *h __rte_unused,
- uint8_t *tuple __rte_unused, unsigned int tuple_len __rte_unused,
- uint32_t desired_value __rte_unused,
- unsigned int attempts __rte_unused,
- rte_thash_check_tuple_t fn __rte_unused, void *userdata __rte_unused)
+rte_thash_adjust_tuple(struct rte_thash_ctx *ctx,
+ struct rte_thash_subtuple_helper *h,
+ uint8_t *tuple, unsigned int tuple_len,
+ uint32_t desired_value, unsigned int attempts,
+ rte_thash_check_tuple_t fn, void *userdata)
{
- return 0;
+ uint32_t tmp_tuple[tuple_len / sizeof(uint32_t)];
+ unsigned int i, j, ret = 0;
+ uint32_t hash, adj_bits;
+ uint8_t bit;
+ const uint8_t *hash_key;
+
+ if ((ctx == NULL) || (h == NULL) || (tuple == NULL) ||
+ (tuple_len % sizeof(uint32_t) != 0) || (attempts <= 0))
+ return -EINVAL;
+
+ hash_key = rte_thash_get_key(ctx);
+
+ for (i = 0; i < attempts; i++) {
+ for (j = 0; j < (tuple_len / 4); j++)
+ tmp_tuple[j] =
+ rte_be_to_cpu_32(*(uint32_t *)&tuple[j * 4]);
+
+ hash = rte_softrss(tmp_tuple, tuple_len / 4, hash_key);
+ adj_bits = rte_thash_get_complement(h, hash, desired_value);
+
+ /*
+ * Hint: LSB of adj_bits corresponds to
+ * offset + len bit of tuple
+ */
+ for (j = 0; j < sizeof(uint32_t) * CHAR_BIT; j++) {
+ bit = (adj_bits >> j) & 0x1;
+ if (bit)
+ xor_bit(tuple, bit, h->tuple_offset +
+ h->tuple_len - 1 - j);
+ }
+
+ if (fn != NULL) {
+ ret = (fn(userdata, tuple)) ? 0 : -EEXIST;
+ if (ret == 0)
+ return 0;
+ else if (i < (attempts - 1)) {
+ /* Update tuple with random bits */
+ for (j = 0; j < h->tuple_len; j++) {
+ bit = rte_rand() & 0x1;
+ if (bit)
+ xor_bit(tuple, bit,
+ h->tuple_offset +
+ h->tuple_len - 1 - j);
+ }
+ }
+ } else
+ return 0;
+ }
+
+ return ret;
}
--
2.7.4
