Commit 0a4a5235 authored by Michal Berger's avatar Michal Berger Committed by Tomasz Zawadzki
Browse files

test/scheduler: Speed up mapping of the cpu topology 



Currently, for systems with multiple nodes and >100 cpu threads
the time needed for map_cpus() to complete is ~4s. The bottleneck
here is the is_cpu_online() which performs quite a lot of steps
to yield such a simple information.

Introduce new wrapper functions that will simply read from cpu's
online attribute with a special case for cpu0 using the old routine.

This drops the time needed to complete the map, on the same system,
from ~4s to ~0.6s

Change-Id: I66e004f5bb7505e47d70c487fe74a1b727856f58
Signed-off-by: default avatarMichal Berger <michal.berger@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/21030


Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: default avatarKarol Latecki <karol.latecki@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <jim.harris@samsung.com>
parent 7278ac94

test/scheduler/common.sh

+23 −5
Original line number Diff line number Diff line
@@ -58,7 +58,7 @@ map_cpus_node() { 
	local cpu_idx core_idx



	for cpu_idx in $(parse_cpu_list "$sysfs_node/node$node_idx/cpulist"); do

		if is_cpu_online "$cpu_idx"; then

		if is_cpu_online_f "$cpu_idx"; then

			core_idx=$(< "$sysfs_cpu/cpu$cpu_idx/topology/core_id")

			local -n _cpu_core_map=node_${node_idx}_core_${core_idx}

			_cpu_core_map+=("$cpu_idx") cpu_core_map[cpu_idx]=$core_idx
@@ -134,14 +134,32 @@ is_cpu_offline() { 
	! is_cpu_online "$1"

}



is_cpu_online_f() {

	local cpu=$1



	if ((cpu == 0)); then

		# cpu0 is special as it requires proper support in the kernel to be hot pluggable.

		# As such, it usually does not have its own online attribute so always check the

		# online list instead.

		is_cpu_online "$cpu"

	else

		[[ -e $sysfs_cpu/cpu$cpu/online ]] || return 1

		(($(< "$sysfs_cpu/cpu$cpu/online") == 1))

	fi

}



is_cpu_offline_f() {

	! is_cpu_online_f "$1"

}



online_cpu() {

	is_cpu_offline "$1" || return 0

	[[ -e $sysfs_cpu/cpu$1/online ]] && echo 1 > "$sysfs_cpu/cpu$1/online"

	is_cpu_offline_f "$1" || return 0

	echo 1 > "$sysfs_cpu/cpu$1/online"

}



offline_cpu() {

	is_cpu_online "$1" || return 0

	[[ -e $sysfs_cpu/cpu$1/online ]] && echo 0 > "$sysfs_cpu/cpu$1/online"

	is_cpu_online_f "$1" || return 0

	echo 0 > "$sysfs_cpu/cpu$1/online"

}



mask_cpus() {