Commit 408bb168 authored by Dariusz Stojaczyk's avatar Dariusz Stojaczyk Committed by Ben Walker
Browse files

event/reactor: take into account 1 extra slot in event mempools 



The following assumes we use env_dpdk underneath.

rte_mempools use rte_rings internally. When creating
a mempool with capacity N, we internally try to create
a ring with least N+1 size. That's because rte_rings
need one extra empty element to differentiate between
the full and empty state. To make it worse, the ring
size has to be a power of two, so rte_mempools use
`rte_align32pow2(mp->size + 1)` for the size calculation.
And rte_ring memory has to be physically contiguous.

Allocating a mempool of capacity 262144 requires at
least (2 * 262144) * sizeof(void *) = 4MB memory. This
made us require at least 2 physically contiguous
2MB hugepages.

Change-Id: Iabc984a29a60c0b2cf5309a78cd1bcce28ac7b3d
Signed-off-by: default avatarDariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/408925


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
parent d546e3d9

lib/event/reactor.c

+8 −2
Original line number Diff line number Diff line
@@ -363,6 +363,12 @@ _spdk_reactor_context_switch_monitor_stop(void *arg1, void *arg2) 
	}

}



static size_t

_spdk_reactor_get_max_event_cnt(uint8_t socket_count)

{

	return 262144 / socket_count - 1;

}



void

spdk_reactor_enable_context_switch_monitor(bool enable)

{
@@ -663,7 +669,7 @@ spdk_reactors_init(unsigned int max_delay_us) 
		if ((1ULL << i) & socket_mask) {

			snprintf(mempool_name, sizeof(mempool_name), "evtpool%d_%d", i, getpid());

			g_spdk_event_mempool[i] = spdk_mempool_create(mempool_name,

						  (262144 / socket_count),

						  _spdk_reactor_get_max_event_cnt(socket_count),

						  sizeof(struct spdk_event),

						  SPDK_MEMPOOL_DEFAULT_CACHE_SIZE, i);
@@ -678,7 +684,7 @@ spdk_reactors_init(unsigned int max_delay_us) 
				 */

				g_spdk_event_mempool[i] = spdk_mempool_create(

								  mempool_name,

								  (262144 / socket_count),

								  _spdk_reactor_get_max_event_cnt(socket_count),

								  sizeof(struct spdk_event),

								  SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,

								  SPDK_ENV_SOCKET_ID_ANY);