From: <pbhagavatula@marvell.com>
To: <jerinj@marvell.com>, Pavan Nikhilesh <pbhagavatula@marvell.com>
Cc: <dev@dpdk.org>
Subject: [dpdk-dev] [PATCH v3 2/5] event/octeontx2: use opposite bucket to store current chunk
Date: Fri, 22 Nov 2019 21:14:27 +0530 [thread overview]
Message-ID: <20191122154431.17416-2-pbhagavatula@marvell.com> (raw)
In-Reply-To: <20191122154431.17416-1-pbhagavatula@marvell.com>
From: Pavan Nikhilesh <pbhagavatula@marvell.com>
Since TIM buckets are always aligned to 32B and our cache line size being
128B, we will always have a cache miss when reading current_chunk pointer.
Avoid the cache miss by storing the current_chunk pointer in the bucket
opposite to the current bucket.
Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
---
drivers/event/octeontx2/otx2_tim_worker.h | 69 ++++++++++++++---------
1 file changed, 41 insertions(+), 28 deletions(-)
diff --git a/drivers/event/octeontx2/otx2_tim_worker.h b/drivers/event/octeontx2/otx2_tim_worker.h
index c896b5433..7b771fbca 100644
--- a/drivers/event/octeontx2/otx2_tim_worker.h
+++ b/drivers/event/octeontx2/otx2_tim_worker.h
@@ -115,20 +115,29 @@ tim_bkt_clr_nent(struct otx2_tim_bkt *bktp)
return __atomic_and_fetch(&bktp->w1, v, __ATOMIC_ACQ_REL);
}
-static __rte_always_inline struct otx2_tim_bkt *
+static __rte_always_inline void
tim_get_target_bucket(struct otx2_tim_ring * const tim_ring,
- const uint32_t rel_bkt, const uint8_t flag)
+ const uint32_t rel_bkt, struct otx2_tim_bkt **bkt,
+ struct otx2_tim_bkt **mirr_bkt, const uint8_t flag)
{
const uint64_t bkt_cyc = rte_rdtsc() - tim_ring->ring_start_cyc;
uint32_t bucket = rte_reciprocal_divide_u64(bkt_cyc,
&tim_ring->fast_div) + rel_bkt;
+ uint32_t mirr_bucket = 0;
- if (flag & OTX2_TIM_BKT_MOD)
+ if (flag & OTX2_TIM_BKT_MOD) {
bucket = bucket % tim_ring->nb_bkts;
- if (flag & OTX2_TIM_BKT_AND)
+ mirr_bucket = (bucket + (tim_ring->nb_bkts >> 1)) %
+ tim_ring->nb_bkts;
+ }
+ if (flag & OTX2_TIM_BKT_AND) {
bucket = bucket & (tim_ring->nb_bkts - 1);
+ mirr_bucket = (bucket + (tim_ring->nb_bkts >> 1)) &
+ (tim_ring->nb_bkts - 1);
+ }
- return &tim_ring->bkt[bucket];
+ *bkt = &tim_ring->bkt[bucket];
+ *mirr_bkt = &tim_ring->bkt[mirr_bucket];
}
static struct otx2_tim_ent *
@@ -153,6 +162,7 @@ tim_clr_bkt(struct otx2_tim_ring * const tim_ring,
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;
@@ -162,8 +172,8 @@ tim_refill_chunk(struct otx2_tim_bkt * const bkt,
(void **)&chunk)))
return NULL;
if (bkt->nb_entry) {
- *(uint64_t *)(((struct otx2_tim_ent *)(uintptr_t)
- bkt->current_chunk) +
+ *(uint64_t *)(((struct otx2_tim_ent *)
+ mirr_bkt->current_chunk) +
tim_ring->nb_chunk_slots) =
(uintptr_t)chunk;
} else {
@@ -180,6 +190,7 @@ tim_refill_chunk(struct otx2_tim_bkt * const bkt,
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;
@@ -190,7 +201,7 @@ tim_insert_chunk(struct otx2_tim_bkt * const bkt,
*(uint64_t *)(chunk + tim_ring->nb_chunk_slots) = 0;
if (bkt->nb_entry) {
*(uint64_t *)(((struct otx2_tim_ent *)(uintptr_t)
- bkt->current_chunk) +
+ mirr_bkt->current_chunk) +
tim_ring->nb_chunk_slots) = (uintptr_t)chunk;
} else {
bkt->first_chunk = (uintptr_t)chunk;
@@ -205,14 +216,15 @@ tim_add_entry_sp(struct otx2_tim_ring * const tim_ring,
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;
- bkt = tim_get_target_bucket(tim_ring, rel_bkt, flags);
-
__retry:
+ tim_get_target_bucket(tim_ring, rel_bkt, &bkt, &mirr_bkt, flags);
+
/* Get Bucket sema*/
lock_sema = tim_bkt_fetch_sema_lock(bkt);
@@ -232,7 +244,7 @@ tim_add_entry_sp(struct otx2_tim_ring * const tim_ring,
: [hbt] "=&r" (hbt_state)
: [w1] "r" ((&bkt->w1))
: "memory"
- );
+ );
#else
do {
hbt_state = __atomic_load_n(&bkt->w1,
@@ -246,15 +258,14 @@ tim_add_entry_sp(struct otx2_tim_ring * const tim_ring,
}
}
}
-
/* Insert the work. */
rem = tim_bkt_fetch_rem(lock_sema);
if (!rem) {
if (flags & OTX2_TIM_ENA_FB)
- chunk = tim_refill_chunk(bkt, tim_ring);
+ chunk = tim_refill_chunk(bkt, mirr_bkt, tim_ring);
if (flags & OTX2_TIM_ENA_DFB)
- chunk = tim_insert_chunk(bkt, tim_ring);
+ chunk = tim_insert_chunk(bkt, mirr_bkt, tim_ring);
if (unlikely(chunk == NULL)) {
bkt->chunk_remainder = 0;
@@ -264,10 +275,10 @@ tim_add_entry_sp(struct otx2_tim_ring * const tim_ring,
tim->state = RTE_EVENT_TIMER_ERROR;
return -ENOMEM;
}
- bkt->current_chunk = (uintptr_t)chunk;
+ mirr_bkt->current_chunk = (uintptr_t)chunk;
bkt->chunk_remainder = tim_ring->nb_chunk_slots - 1;
} else {
- chunk = (struct otx2_tim_ent *)(uintptr_t)bkt->current_chunk;
+ chunk = (struct otx2_tim_ent *)mirr_bkt->current_chunk;
chunk += tim_ring->nb_chunk_slots - rem;
}
@@ -291,13 +302,14 @@ tim_add_entry_mp(struct otx2_tim_ring * const tim_ring,
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:
- bkt = tim_get_target_bucket(tim_ring, rel_bkt, flags);
+ tim_get_target_bucket(tim_ring, rel_bkt, &bkt, &mirr_bkt, flags);
/* Get Bucket sema*/
lock_sema = tim_bkt_fetch_sema_lock(bkt);
@@ -317,7 +329,7 @@ tim_add_entry_mp(struct otx2_tim_ring * const tim_ring,
: [hbt] "=&r" (hbt_state)
: [w1] "r" ((&bkt->w1))
: "memory"
- );
+ );
#else
do {
hbt_state = __atomic_load_n(&bkt->w1,
@@ -358,9 +370,9 @@ tim_add_entry_mp(struct otx2_tim_ring * const tim_ring,
} else if (!rem) {
/* Only one thread can be here*/
if (flags & OTX2_TIM_ENA_FB)
- chunk = tim_refill_chunk(bkt, tim_ring);
+ chunk = tim_refill_chunk(bkt, mirr_bkt, tim_ring);
if (flags & OTX2_TIM_ENA_DFB)
- chunk = tim_insert_chunk(bkt, tim_ring);
+ chunk = tim_insert_chunk(bkt, mirr_bkt, tim_ring);
if (unlikely(chunk == NULL)) {
tim_bkt_set_rem(bkt, 0);
@@ -375,11 +387,11 @@ tim_add_entry_mp(struct otx2_tim_ring * const tim_ring,
(-tim_bkt_fetch_rem(lock_sema)))
lock_sema = __atomic_load_n(&bkt->w1, __ATOMIC_ACQUIRE);
- bkt->current_chunk = (uintptr_t)chunk;
+ 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 *)bkt->current_chunk;
+ chunk = (struct otx2_tim_ent *)mirr_bkt->current_chunk;
chunk += tim_ring->nb_chunk_slots - rem;
*chunk = *pent;
}
@@ -420,6 +432,7 @@ tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
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;
@@ -428,7 +441,7 @@ tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
uint8_t lock_cnt;
__retry:
- bkt = tim_get_target_bucket(tim_ring, rel_bkt, flags);
+ tim_get_target_bucket(tim_ring, rel_bkt, &bkt, &mirr_bkt, flags);
/* Only one thread beyond this. */
lock_sema = tim_bkt_inc_lock(bkt);
@@ -477,7 +490,7 @@ tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
crem = tim_ring->nb_chunk_slots - chunk_remainder;
if (chunk_remainder && crem) {
chunk = ((struct otx2_tim_ent *)
- (uintptr_t)bkt->current_chunk) + crem;
+ mirr_bkt->current_chunk) + crem;
index = tim_cpy_wrk(index, chunk_remainder, chunk, tim,
ents, bkt);
@@ -486,9 +499,9 @@ tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
}
if (flags & OTX2_TIM_ENA_FB)
- chunk = tim_refill_chunk(bkt, tim_ring);
+ chunk = tim_refill_chunk(bkt, mirr_bkt, tim_ring);
if (flags & OTX2_TIM_ENA_DFB)
- chunk = tim_insert_chunk(bkt, tim_ring);
+ chunk = tim_insert_chunk(bkt, mirr_bkt, tim_ring);
if (unlikely(chunk == NULL)) {
tim_bkt_dec_lock(bkt);
@@ -497,14 +510,14 @@ tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
return crem;
}
*(uint64_t *)(chunk + tim_ring->nb_chunk_slots) = 0;
- bkt->current_chunk = (uintptr_t)chunk;
+ 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 *)(uintptr_t)bkt->current_chunk;
+ 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);
--
2.17.1
next prev parent reply other threads:[~2019-11-22 15:44 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-22 15:44 [dpdk-dev] [PATCH v3 1/5] event/octeontx2: fix TIM HW race condition pbhagavatula
2019-11-22 15:44 ` pbhagavatula [this message]
2019-11-22 15:44 ` [dpdk-dev] [PATCH v3 3/5] event/octeontx2: improve chunk pool performance pbhagavatula
2019-11-22 15:44 ` [dpdk-dev] [PATCH v3 4/5] event/octeontx2: update SSO buffers based on timer count pbhagavatula
2019-11-22 15:44 ` [dpdk-dev] [PATCH v3 5/5] event/octeontx2: update start timestamp periodically pbhagavatula
2019-11-22 16:07 ` [dpdk-dev] [PATCH v3 1/5] event/octeontx2: fix TIM HW race condition Pavan Nikhilesh Bhagavatula
2019-11-23 9:00 ` Jerin Jacob
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