Re: [PATCH] eal: allow worker lcore stacks to be allocated from hugepage memory

[Don Wallwork <donw@xsightlabs.com>]

On 5/3/2022 9:08 AM, Wang, Haiyue wrote:
>> -----Original Message-----
>> From: Don Wallwork <donw@xsightlabs.com>
>> Sent: Monday, May 2, 2022 22:11
>> To: dev@dpdk.org
>> Cc: donw@xsightlabs.com; stephen@networkplumber.org; mb@smartsharesystems.com; Burakov, Anatoly
>> <anatoly.burakov@intel.com>; dmitry.kozliuk@gmail.com; Richardson, Bruce <bruce.richardson@intel.com>;
>> Honnappa.Nagarahalli@arm.com; nd@arm.com
>> Subject: [PATCH] eal: allow worker lcore stacks to be allocated from hugepage memory
>>
>> Add support for using hugepages for worker lcore stack memory.  The
>> intent is to improve performance by reducing stack memory related TLB
>> misses and also by using memory local to the NUMA node of each lcore.
>>
>> EAL option '--huge-worker-stack [stack-size-kbytes]' is added to allow
>> the feature to be enabled at runtime.  If the size is not specified,
>> the system pthread stack size will be used.
>>
>> Signed-off-by: Don Wallwork <donw@xsightlabs.com>
>> ---
>>   lib/eal/common/eal_common_options.c | 31 ++++++++++++++
>>   lib/eal/common/eal_internal_cfg.h   |  4 ++
>>   lib/eal/common/eal_options.h        |  2 +
>>   lib/eal/linux/eal.c                 | 65 ++++++++++++++++++++++++++++-
>>   4 files changed, 100 insertions(+), 2 deletions(-)
>>
>> diff --git a/lib/eal/common/eal_common_options.c b/lib/eal/common/eal_common_options.c
>> index f247a42455..be9db9ee37 100644
>> --- a/lib/eal/common/eal_common_options.c
>> +++ b/lib/eal/common/eal_common_options.c
>> @@ -103,6 +103,7 @@ eal_long_options[] = {
>>   	{OPT_TELEMETRY,         0, NULL, OPT_TELEMETRY_NUM        },
>>   	{OPT_NO_TELEMETRY,      0, NULL, OPT_NO_TELEMETRY_NUM     },
>>   	{OPT_FORCE_MAX_SIMD_BITWIDTH, 1, NULL, OPT_FORCE_MAX_SIMD_BITWIDTH_NUM},
>> +	{OPT_HUGE_WORKER_STACK, 2, NULL, OPT_HUGE_WORKER_STACK_NUM     },
>>
>>   	{0,                     0, NULL, 0                        }
>>   };
>> @@ -1618,6 +1619,22 @@ eal_parse_huge_unlink(const char *arg, struct hugepage_file_discipline *out)
>>   	return -1;
>>   }
>>
>> +static int
>> +eal_parse_huge_worker_stack(const char *arg, size_t *huge_worker_stack_size)
>> +{
>> +	size_t worker_stack_size;
>> +	if (arg == NULL) {
>> +		*huge_worker_stack_size = USE_OS_STACK_SIZE;
>> +		return 0;
>> +	}
>> +	worker_stack_size = atoi(arg);
>> +	if (worker_stack_size == 0)
>> +		return -1;
> Should we also to check "worker_stack_size *1024  < PTHREAD_STACK_MIN" ?
This may be too restrictive in certain environments.  For example, 
memory constrained platforms may require a smaller worker stack size 
than this limit would allow.
>> +
>> +	*huge_worker_stack_size = worker_stack_size * 1024;
>> +	return 0;
>> +}
>> +
>
>> --
>> 2.17.1