event/octeontx2: optimize timer Arm routine
[dpdk.git] / drivers / event / octeontx2 / otx2_tim_worker.h
index ccb137d..5ece8fd 100644 (file)
@@ -7,6 +7,13 @@
 
 #include "otx2_tim_evdev.h"
 
+static inline uint8_t
+tim_bkt_fetch_lock(uint64_t w1)
+{
+       return (w1 >> TIM_BUCKET_W1_S_LOCK) &
+               TIM_BUCKET_W1_M_LOCK;
+}
+
 static inline int16_t
 tim_bkt_fetch_rem(uint64_t w1)
 {
@@ -77,7 +84,13 @@ tim_bkt_inc_lock(struct otx2_tim_bkt *bktp)
 static inline void
 tim_bkt_dec_lock(struct otx2_tim_bkt *bktp)
 {
-       __atomic_add_fetch(&bktp->lock, 0xff, __ATOMIC_RELEASE);
+       __atomic_fetch_sub(&bktp->lock, 1, __ATOMIC_RELEASE);
+}
+
+static inline void
+tim_bkt_dec_lock_relaxed(struct otx2_tim_bkt *bktp)
+{
+       __atomic_fetch_sub(&bktp->lock, 1, __ATOMIC_RELAXED);
 }
 
 static inline uint32_t
@@ -108,4 +121,478 @@ tim_bkt_clr_nent(struct otx2_tim_bkt *bktp)
        return __atomic_and_fetch(&bktp->w1, v, __ATOMIC_ACQ_REL);
 }
 
+static inline uint64_t
+tim_bkt_fast_mod(uint64_t n, uint64_t d, struct rte_reciprocal_u64 R)
+{
+       return (n - (d * rte_reciprocal_divide_u64(n, &R)));
+}
+
+static __rte_always_inline void
+tim_get_target_bucket(struct otx2_tim_ring *const tim_ring,
+                     const uint32_t rel_bkt, struct otx2_tim_bkt **bkt,
+                     struct otx2_tim_bkt **mirr_bkt)
+{
+       const uint64_t bkt_cyc = rte_rdtsc() - tim_ring->ring_start_cyc;
+       uint64_t bucket =
+               rte_reciprocal_divide_u64(bkt_cyc, &tim_ring->fast_div) +
+               rel_bkt;
+       uint64_t mirr_bucket = 0;
+
+       bucket =
+               tim_bkt_fast_mod(bucket, tim_ring->nb_bkts, tim_ring->fast_bkt);
+       mirr_bucket = tim_bkt_fast_mod(bucket + (tim_ring->nb_bkts >> 1),
+                                      tim_ring->nb_bkts, tim_ring->fast_bkt);
+       *bkt = &tim_ring->bkt[bucket];
+       *mirr_bkt = &tim_ring->bkt[mirr_bucket];
+}
+
+static struct otx2_tim_ent *
+tim_clr_bkt(struct otx2_tim_ring * const tim_ring,
+           struct otx2_tim_bkt * const bkt)
+{
+#define TIM_MAX_OUTSTANDING_OBJ                64
+       void *pend_chunks[TIM_MAX_OUTSTANDING_OBJ];
+       struct otx2_tim_ent *chunk;
+       struct otx2_tim_ent *pnext;
+       uint8_t objs = 0;
+
+
+       chunk = ((struct otx2_tim_ent *)(uintptr_t)bkt->first_chunk);
+       chunk = (struct otx2_tim_ent *)(uintptr_t)(chunk +
+                       tim_ring->nb_chunk_slots)->w0;
+       while (chunk) {
+               pnext = (struct otx2_tim_ent *)(uintptr_t)
+                       ((chunk + tim_ring->nb_chunk_slots)->w0);
+               if (objs == TIM_MAX_OUTSTANDING_OBJ) {
+                       rte_mempool_put_bulk(tim_ring->chunk_pool, pend_chunks,
+                                            objs);
+                       objs = 0;
+               }
+               pend_chunks[objs++] = chunk;
+               chunk = pnext;
+       }
+
+       if (objs)
+               rte_mempool_put_bulk(tim_ring->chunk_pool, pend_chunks,
+                               objs);
+
+       return (struct otx2_tim_ent *)(uintptr_t)bkt->first_chunk;
+}
+
+static struct otx2_tim_ent *
+tim_refill_chunk(struct otx2_tim_bkt * const bkt,
+                struct otx2_tim_bkt * const mirr_bkt,
+                struct otx2_tim_ring * const tim_ring)
+{
+       struct otx2_tim_ent *chunk;
+
+       if (bkt->nb_entry || !bkt->first_chunk) {
+               if (unlikely(rte_mempool_get(tim_ring->chunk_pool,
+                                            (void **)&chunk)))
+                       return NULL;
+               if (bkt->nb_entry) {
+                       *(uint64_t *)(((struct otx2_tim_ent *)
+                                               mirr_bkt->current_chunk) +
+                                       tim_ring->nb_chunk_slots) =
+                               (uintptr_t)chunk;
+               } else {
+                       bkt->first_chunk = (uintptr_t)chunk;
+               }
+       } else {
+               chunk = tim_clr_bkt(tim_ring, bkt);
+               bkt->first_chunk = (uintptr_t)chunk;
+       }
+       *(uint64_t *)(chunk + tim_ring->nb_chunk_slots) = 0;
+
+       return chunk;
+}
+
+static struct otx2_tim_ent *
+tim_insert_chunk(struct otx2_tim_bkt * const bkt,
+                struct otx2_tim_bkt * const mirr_bkt,
+                struct otx2_tim_ring * const tim_ring)
+{
+       struct otx2_tim_ent *chunk;
+
+       if (unlikely(rte_mempool_get(tim_ring->chunk_pool, (void **)&chunk)))
+               return NULL;
+
+       *(uint64_t *)(chunk + tim_ring->nb_chunk_slots) = 0;
+       if (bkt->nb_entry) {
+               *(uint64_t *)(((struct otx2_tim_ent *)(uintptr_t)
+                                       mirr_bkt->current_chunk) +
+                               tim_ring->nb_chunk_slots) = (uintptr_t)chunk;
+       } else {
+               bkt->first_chunk = (uintptr_t)chunk;
+       }
+       return chunk;
+}
+
+static __rte_always_inline int
+tim_add_entry_sp(struct otx2_tim_ring * const tim_ring,
+                const uint32_t rel_bkt,
+                struct rte_event_timer * const tim,
+                const struct otx2_tim_ent * const pent,
+                const uint8_t flags)
+{
+       struct otx2_tim_bkt *mirr_bkt;
+       struct otx2_tim_ent *chunk;
+       struct otx2_tim_bkt *bkt;
+       uint64_t lock_sema;
+       int16_t rem;
+
+__retry:
+       tim_get_target_bucket(tim_ring, rel_bkt, &bkt, &mirr_bkt);
+
+       /* Get Bucket sema*/
+       lock_sema = tim_bkt_fetch_sema_lock(bkt);
+
+       /* Bucket related checks. */
+       if (unlikely(tim_bkt_get_hbt(lock_sema))) {
+               if (tim_bkt_get_nent(lock_sema) != 0) {
+                       uint64_t hbt_state;
+#ifdef RTE_ARCH_ARM64
+                       asm volatile("          ldxr %[hbt], [%[w1]]    \n"
+                                    "          tbz %[hbt], 33, dne%=   \n"
+                                    "          sevl                    \n"
+                                    "rty%=:    wfe                     \n"
+                                    "          ldxr %[hbt], [%[w1]]    \n"
+                                    "          tbnz %[hbt], 33, rty%=  \n"
+                                    "dne%=:                            \n"
+                                    : [hbt] "=&r"(hbt_state)
+                                    : [w1] "r"((&bkt->w1))
+                                    : "memory");
+#else
+                       do {
+                               hbt_state = __atomic_load_n(&bkt->w1,
+                                                           __ATOMIC_RELAXED);
+                       } while (hbt_state & BIT_ULL(33));
+#endif
+
+                       if (!(hbt_state & BIT_ULL(34))) {
+                               tim_bkt_dec_lock(bkt);
+                               goto __retry;
+                       }
+               }
+       }
+       /* Insert the work. */
+       rem = tim_bkt_fetch_rem(lock_sema);
+
+       if (!rem) {
+               if (flags & OTX2_TIM_ENA_FB)
+                       chunk = tim_refill_chunk(bkt, mirr_bkt, tim_ring);
+               if (flags & OTX2_TIM_ENA_DFB)
+                       chunk = tim_insert_chunk(bkt, mirr_bkt, tim_ring);
+
+               if (unlikely(chunk == NULL)) {
+                       bkt->chunk_remainder = 0;
+                       tim->impl_opaque[0] = 0;
+                       tim->impl_opaque[1] = 0;
+                       tim->state = RTE_EVENT_TIMER_ERROR;
+                       tim_bkt_dec_lock(bkt);
+                       return -ENOMEM;
+               }
+               mirr_bkt->current_chunk = (uintptr_t)chunk;
+               bkt->chunk_remainder = tim_ring->nb_chunk_slots - 1;
+       } else {
+               chunk = (struct otx2_tim_ent *)mirr_bkt->current_chunk;
+               chunk += tim_ring->nb_chunk_slots - rem;
+       }
+
+       /* Copy work entry. */
+       *chunk = *pent;
+
+       tim->impl_opaque[0] = (uintptr_t)chunk;
+       tim->impl_opaque[1] = (uintptr_t)bkt;
+       __atomic_store_n(&tim->state, RTE_EVENT_TIMER_ARMED, __ATOMIC_RELEASE);
+       tim_bkt_inc_nent(bkt);
+       tim_bkt_dec_lock_relaxed(bkt);
+
+       return 0;
+}
+
+static __rte_always_inline int
+tim_add_entry_mp(struct otx2_tim_ring * const tim_ring,
+                const uint32_t rel_bkt,
+                struct rte_event_timer * const tim,
+                const struct otx2_tim_ent * const pent,
+                const uint8_t flags)
+{
+       struct otx2_tim_bkt *mirr_bkt;
+       struct otx2_tim_ent *chunk;
+       struct otx2_tim_bkt *bkt;
+       uint64_t lock_sema;
+       int16_t rem;
+
+__retry:
+       tim_get_target_bucket(tim_ring, rel_bkt, &bkt, &mirr_bkt);
+       /* Get Bucket sema*/
+       lock_sema = tim_bkt_fetch_sema_lock(bkt);
+
+       /* Bucket related checks. */
+       if (unlikely(tim_bkt_get_hbt(lock_sema))) {
+               if (tim_bkt_get_nent(lock_sema) != 0) {
+                       uint64_t hbt_state;
+#ifdef RTE_ARCH_ARM64
+                       asm volatile("          ldxr %[hbt], [%[w1]]    \n"
+                                    "          tbz %[hbt], 33, dne%=   \n"
+                                    "          sevl                    \n"
+                                    "rty%=:    wfe                     \n"
+                                    "          ldxr %[hbt], [%[w1]]    \n"
+                                    "          tbnz %[hbt], 33, rty%=  \n"
+                                    "dne%=:                            \n"
+                                    : [hbt] "=&r"(hbt_state)
+                                    : [w1] "r"((&bkt->w1))
+                                    : "memory");
+#else
+                       do {
+                               hbt_state = __atomic_load_n(&bkt->w1,
+                                                           __ATOMIC_RELAXED);
+                       } while (hbt_state & BIT_ULL(33));
+#endif
+
+                       if (!(hbt_state & BIT_ULL(34))) {
+                               tim_bkt_dec_lock(bkt);
+                               goto __retry;
+                       }
+               }
+       }
+
+       rem = tim_bkt_fetch_rem(lock_sema);
+       if (rem < 0) {
+               tim_bkt_dec_lock(bkt);
+#ifdef RTE_ARCH_ARM64
+               uint64_t w1;
+               asm volatile("          ldxr %[w1], [%[crem]]   \n"
+                            "          tbz %[w1], 63, dne%=            \n"
+                            "          sevl                            \n"
+                            "rty%=:    wfe                             \n"
+                            "          ldxr %[w1], [%[crem]]   \n"
+                            "          tbnz %[w1], 63, rty%=           \n"
+                            "dne%=:                                    \n"
+                            : [w1] "=&r"(w1)
+                            : [crem] "r"(&bkt->w1)
+                            : "memory");
+#else
+               while (__atomic_load_n((int64_t *)&bkt->w1, __ATOMIC_RELAXED) <
+                      0)
+                       ;
+#endif
+               goto __retry;
+       } else if (!rem) {
+               /* Only one thread can be here*/
+               if (flags & OTX2_TIM_ENA_FB)
+                       chunk = tim_refill_chunk(bkt, mirr_bkt, tim_ring);
+               if (flags & OTX2_TIM_ENA_DFB)
+                       chunk = tim_insert_chunk(bkt, mirr_bkt, tim_ring);
+
+               if (unlikely(chunk == NULL)) {
+                       tim->impl_opaque[0] = 0;
+                       tim->impl_opaque[1] = 0;
+                       tim->state = RTE_EVENT_TIMER_ERROR;
+                       tim_bkt_set_rem(bkt, 0);
+                       tim_bkt_dec_lock(bkt);
+                       return -ENOMEM;
+               }
+               *chunk = *pent;
+               if (tim_bkt_fetch_lock(lock_sema)) {
+                       do {
+                               lock_sema = __atomic_load_n(&bkt->w1,
+                                                           __ATOMIC_RELAXED);
+                       } while (tim_bkt_fetch_lock(lock_sema) - 1);
+                       rte_atomic_thread_fence(__ATOMIC_ACQUIRE);
+               }
+               mirr_bkt->current_chunk = (uintptr_t)chunk;
+               __atomic_store_n(&bkt->chunk_remainder,
+                               tim_ring->nb_chunk_slots - 1, __ATOMIC_RELEASE);
+       } else {
+               chunk = (struct otx2_tim_ent *)mirr_bkt->current_chunk;
+               chunk += tim_ring->nb_chunk_slots - rem;
+               *chunk = *pent;
+       }
+
+       tim->impl_opaque[0] = (uintptr_t)chunk;
+       tim->impl_opaque[1] = (uintptr_t)bkt;
+       __atomic_store_n(&tim->state, RTE_EVENT_TIMER_ARMED, __ATOMIC_RELEASE);
+       tim_bkt_inc_nent(bkt);
+       tim_bkt_dec_lock_relaxed(bkt);
+
+       return 0;
+}
+
+static inline uint16_t
+tim_cpy_wrk(uint16_t index, uint16_t cpy_lmt,
+           struct otx2_tim_ent *chunk,
+           struct rte_event_timer ** const tim,
+           const struct otx2_tim_ent * const ents,
+           const struct otx2_tim_bkt * const bkt)
+{
+       for (; index < cpy_lmt; index++) {
+               *chunk = *(ents + index);
+               tim[index]->impl_opaque[0] = (uintptr_t)chunk++;
+               tim[index]->impl_opaque[1] = (uintptr_t)bkt;
+               tim[index]->state = RTE_EVENT_TIMER_ARMED;
+       }
+
+       return index;
+}
+
+/* Burst mode functions */
+static inline int
+tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
+                  const uint16_t rel_bkt,
+                  struct rte_event_timer ** const tim,
+                  const struct otx2_tim_ent *ents,
+                  const uint16_t nb_timers, const uint8_t flags)
+{
+       struct otx2_tim_ent *chunk = NULL;
+       struct otx2_tim_bkt *mirr_bkt;
+       struct otx2_tim_bkt *bkt;
+       uint16_t chunk_remainder;
+       uint16_t index = 0;
+       uint64_t lock_sema;
+       int16_t rem, crem;
+       uint8_t lock_cnt;
+
+__retry:
+       tim_get_target_bucket(tim_ring, rel_bkt, &bkt, &mirr_bkt);
+
+       /* Only one thread beyond this. */
+       lock_sema = tim_bkt_inc_lock(bkt);
+       lock_cnt = (uint8_t)
+               ((lock_sema >> TIM_BUCKET_W1_S_LOCK) & TIM_BUCKET_W1_M_LOCK);
+
+       if (lock_cnt) {
+               tim_bkt_dec_lock(bkt);
+#ifdef RTE_ARCH_ARM64
+               asm volatile("          ldxrb %w[lock_cnt], [%[lock]]   \n"
+                            "          tst %w[lock_cnt], 255           \n"
+                            "          beq dne%=                       \n"
+                            "          sevl                            \n"
+                            "rty%=:    wfe                             \n"
+                            "          ldxrb %w[lock_cnt], [%[lock]]   \n"
+                            "          tst %w[lock_cnt], 255           \n"
+                            "          bne rty%=                       \n"
+                            "dne%=:                                    \n"
+                            : [lock_cnt] "=&r"(lock_cnt)
+                            : [lock] "r"(&bkt->lock)
+                            : "memory");
+#else
+               while (__atomic_load_n(&bkt->lock, __ATOMIC_RELAXED))
+                       ;
+#endif
+               goto __retry;
+       }
+
+       /* Bucket related checks. */
+       if (unlikely(tim_bkt_get_hbt(lock_sema))) {
+               if (tim_bkt_get_nent(lock_sema) != 0) {
+                       uint64_t hbt_state;
+#ifdef RTE_ARCH_ARM64
+                       asm volatile("          ldxr %[hbt], [%[w1]]    \n"
+                                    "          tbz %[hbt], 33, dne%=   \n"
+                                    "          sevl                    \n"
+                                    "rty%=:    wfe                     \n"
+                                    "          ldxr %[hbt], [%[w1]]    \n"
+                                    "          tbnz %[hbt], 33, rty%=  \n"
+                                    "dne%=:                            \n"
+                                    : [hbt] "=&r"(hbt_state)
+                                    : [w1] "r"((&bkt->w1))
+                                    : "memory");
+#else
+                       do {
+                               hbt_state = __atomic_load_n(&bkt->w1,
+                                                           __ATOMIC_RELAXED);
+                       } while (hbt_state & BIT_ULL(33));
+#endif
+
+                       if (!(hbt_state & BIT_ULL(34))) {
+                               tim_bkt_dec_lock(bkt);
+                               goto __retry;
+                       }
+               }
+       }
+
+       chunk_remainder = tim_bkt_fetch_rem(lock_sema);
+       rem = chunk_remainder - nb_timers;
+       if (rem < 0) {
+               crem = tim_ring->nb_chunk_slots - chunk_remainder;
+               if (chunk_remainder && crem) {
+                       chunk = ((struct otx2_tim_ent *)
+                                       mirr_bkt->current_chunk) + crem;
+
+                       index = tim_cpy_wrk(index, chunk_remainder, chunk, tim,
+                                           ents, bkt);
+                       tim_bkt_sub_rem(bkt, chunk_remainder);
+                       tim_bkt_add_nent(bkt, chunk_remainder);
+               }
+
+               if (flags & OTX2_TIM_ENA_FB)
+                       chunk = tim_refill_chunk(bkt, mirr_bkt, tim_ring);
+               if (flags & OTX2_TIM_ENA_DFB)
+                       chunk = tim_insert_chunk(bkt, mirr_bkt, tim_ring);
+
+               if (unlikely(chunk == NULL)) {
+                       tim_bkt_dec_lock(bkt);
+                       rte_errno = ENOMEM;
+                       tim[index]->state = RTE_EVENT_TIMER_ERROR;
+                       return crem;
+               }
+               *(uint64_t *)(chunk + tim_ring->nb_chunk_slots) = 0;
+               mirr_bkt->current_chunk = (uintptr_t)chunk;
+               tim_cpy_wrk(index, nb_timers, chunk, tim, ents, bkt);
+
+               rem = nb_timers - chunk_remainder;
+               tim_bkt_set_rem(bkt, tim_ring->nb_chunk_slots - rem);
+               tim_bkt_add_nent(bkt, rem);
+       } else {
+               chunk = (struct otx2_tim_ent *)mirr_bkt->current_chunk;
+               chunk += (tim_ring->nb_chunk_slots - chunk_remainder);
+
+               tim_cpy_wrk(index, nb_timers, chunk, tim, ents, bkt);
+               tim_bkt_sub_rem(bkt, nb_timers);
+               tim_bkt_add_nent(bkt, nb_timers);
+       }
+
+       tim_bkt_dec_lock(bkt);
+
+       return nb_timers;
+}
+
+static int
+tim_rm_entry(struct rte_event_timer *tim)
+{
+       struct otx2_tim_ent *entry;
+       struct otx2_tim_bkt *bkt;
+       uint64_t lock_sema;
+
+       if (tim->impl_opaque[1] == 0 || tim->impl_opaque[0] == 0)
+               return -ENOENT;
+
+       entry = (struct otx2_tim_ent *)(uintptr_t)tim->impl_opaque[0];
+       if (entry->wqe != tim->ev.u64) {
+               tim->impl_opaque[0] = 0;
+               tim->impl_opaque[1] = 0;
+               return -ENOENT;
+       }
+
+       bkt = (struct otx2_tim_bkt *)(uintptr_t)tim->impl_opaque[1];
+       lock_sema = tim_bkt_inc_lock(bkt);
+       if (tim_bkt_get_hbt(lock_sema) || !tim_bkt_get_nent(lock_sema)) {
+               tim->impl_opaque[0] = 0;
+               tim->impl_opaque[1] = 0;
+               tim_bkt_dec_lock(bkt);
+               return -ENOENT;
+       }
+
+       entry->w0 = 0;
+       entry->wqe = 0;
+       tim->state = RTE_EVENT_TIMER_CANCELED;
+       tim->impl_opaque[0] = 0;
+       tim->impl_opaque[1] = 0;
+       tim_bkt_dec_lock(bkt);
+
+       return 0;
+}
+
 #endif /* __OTX2_TIM_WORKER_H__ */