Re: [dpdk-dev] [PATCH v2] log: add API to check if a logtype can log in a given level

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 3/12/2020 1:41 PM, David Marchand wrote:
> On Tue, Mar 3, 2020 at 7:18 PM Ferruh Yigit <ferruh.yigit@intel.com> wrote:
>>
>> This is a helper function in case components would like to do more work
>> than just logging a message based on log level, like for example
>> collecting some stats if the log type is DEBUG etc..
>>
>> A few existing relevant usage converted to this new API.
>>
>> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
>> ---
>> Cc: David Marchand <david.marchand@redhat.com>
>> Cc: Thomas Monjalon <thomas@monjalon.net>
>> Cc: Stephen Hemminger <stephen@networkplumber.org>
>>
>> v2:
>> * Convert API return type to 'bool'. Removed custom definitions from
>>   'ionic' PMD for this.
>> ---
>>  drivers/bus/fslmc/fslmc_bus.c                |  7 +------
>>  drivers/common/qat/qat_logs.c                |  7 ++-----
>>  drivers/net/enic/enic_fm_flow.c              |  2 +-
>>  drivers/net/ionic/ionic_osdep.h              |  6 ------
>>  drivers/net/mlx5/mlx5_mr.c                   |  2 +-
>>  lib/librte_eal/common/eal_common_log.c       | 18 ++++++++++++++++++
>>  lib/librte_eal/common/include/rte_log.h      | 14 ++++++++++++++
>>  lib/librte_eal/rte_eal_version.map           |  3 +++
>>  lib/librte_flow_classify/rte_flow_classify.c |  7 ++-----
>>  9 files changed, 42 insertions(+), 24 deletions(-)
>>
>> diff --git a/drivers/bus/fslmc/fslmc_bus.c b/drivers/bus/fslmc/fslmc_bus.c
>> index b3e964aa9..afbd82e8d 100644
>> --- a/drivers/bus/fslmc/fslmc_bus.c
>> +++ b/drivers/bus/fslmc/fslmc_bus.c
>> @@ -115,14 +115,9 @@ static void
>>  dump_device_list(void)
>>  {
>>         struct rte_dpaa2_device *dev;
>> -       uint32_t global_log_level;
>> -       int local_log_level;
>>
>>         /* Only if the log level has been set to Debugging, print list */
>> -       global_log_level = rte_log_get_global_level();
>> -       local_log_level = rte_log_get_level(dpaa2_logtype_bus);
>> -       if (global_log_level == RTE_LOG_DEBUG ||
>> -           local_log_level == RTE_LOG_DEBUG) {
>> +       if (rte_log_can_log(dpaa2_logtype_bus, RTE_LOG_DEBUG)) {
> 
> Here, this is a change in behavior, but it aligns this driver to the
> rest of dpdk, and we got a ack from Hemant.
> 
> 
>>                 DPAA2_BUS_LOG(DEBUG, "List of devices scanned on bus:");
>>                 TAILQ_FOREACH(dev, &rte_fslmc_bus.device_list, next) {
>>                         DPAA2_BUS_LOG(DEBUG, "\t\t%s", dev->device.name);
>> diff --git a/drivers/common/qat/qat_logs.c b/drivers/common/qat/qat_logs.c
>> index f97aba19d..dfd0cbe5d 100644
>> --- a/drivers/common/qat/qat_logs.c
>> +++ b/drivers/common/qat/qat_logs.c
>> @@ -14,12 +14,9 @@ int
>>  qat_hexdump_log(uint32_t level, uint32_t logtype, const char *title,
>>                 const void *buf, unsigned int len)
>>  {
>> -       if (level > rte_log_get_global_level())
>> -               return 0;
>> -       if (level > (uint32_t)(rte_log_get_level(logtype)))
>> -               return 0;
>> +       if (rte_log_can_log(logtype, level))
>> +               rte_hexdump(rte_log_get_stream(), title, buf, len);
>>
>> -       rte_hexdump(rte_log_get_stream(), title, buf, len);
>>         return 0;
>>  }
>>
>> diff --git a/drivers/net/enic/enic_fm_flow.c b/drivers/net/enic/enic_fm_flow.c
>> index c0ddfe9ba..d815f369e 100644
>> --- a/drivers/net/enic/enic_fm_flow.c
>> +++ b/drivers/net/enic/enic_fm_flow.c
>> @@ -1504,7 +1504,7 @@ enic_fm_dump_tcam_entry(const struct fm_tcam_match_entry *fm_match,
>>                         const struct fm_action *fm_action,
>>                         uint8_t ingress)
>>  {
>> -       if (rte_log_get_level(enic_pmd_logtype) < (int)RTE_LOG_DEBUG)
>> +       if (!rte_log_can_log(enic_pmd_logtype, RTE_LOG_DEBUG))
>>                 return;
>>         enic_fm_dump_tcam_match(fm_match, ingress);
>>         enic_fm_dump_tcam_actions(fm_action);
>> diff --git a/drivers/net/ionic/ionic_osdep.h b/drivers/net/ionic/ionic_osdep.h
>> index ecdbc24e6..e04bb8f65 100644
>> --- a/drivers/net/ionic/ionic_osdep.h
>> +++ b/drivers/net/ionic/ionic_osdep.h
>> @@ -44,12 +44,6 @@ typedef uint16_t __le16;
>>  typedef uint32_t __le32;
>>  typedef uint64_t __le64;
>>
>> -#ifndef __cplusplus
>> -typedef uint8_t bool;
>> -#define false   0
>> -#define true    1
>> -#endif
>> -
>>  static inline uint32_t div_round_up(uint32_t n, uint32_t d)
>>  {
>>         return (n + d - 1) / d;
>> diff --git a/drivers/net/mlx5/mlx5_mr.c b/drivers/net/mlx5/mlx5_mr.c
>> index cb97c876e..6aa578646 100644
>> --- a/drivers/net/mlx5/mlx5_mr.c
>> +++ b/drivers/net/mlx5/mlx5_mr.c
>> @@ -1597,7 +1597,7 @@ mlx5_mr_release(struct mlx5_ibv_shared *sh)
>>  {
>>         struct mlx5_mr *mr_next;
>>
>> -       if (rte_log_get_level(mlx5_logtype) == RTE_LOG_DEBUG)
>> +       if (rte_log_can_log(mlx5_logtype, RTE_LOG_DEBUG))
>>                 mlx5_mr_dump_dev(sh);
>>         rte_rwlock_write_lock(&sh->mr.rwlock);
>>         /* Detach from MR list and move to free list. */
>> diff --git a/lib/librte_eal/common/eal_common_log.c b/lib/librte_eal/common/eal_common_log.c
>> index c0efd5214..679e7326f 100644
>> --- a/lib/librte_eal/common/eal_common_log.c
>> +++ b/lib/librte_eal/common/eal_common_log.c
>> @@ -112,6 +112,24 @@ rte_log_get_level(uint32_t type)
>>         return rte_logs.dynamic_types[type].loglevel;
>>  }
>>
>> +bool
>> +rte_log_can_log(uint32_t logtype, uint32_t level)
>> +{
>> +       int log_level;
>> +
>> +       if (level > rte_log_get_global_level())
>> +               return false;
>> +
>> +       log_level = rte_log_get_level(logtype);
>> +       if (log_level < 0)
>> +               return false;
>> +
>> +       if (level > (uint32_t)log_level)
>> +               return false;
>> +
>> +       return true;
>> +}
>> +
>>  int
>>  rte_log_set_level(uint32_t type, uint32_t level)
>>  {
>> diff --git a/lib/librte_eal/common/include/rte_log.h b/lib/librte_eal/common/include/rte_log.h
>> index 1bb0e6694..2d1bae5c4 100644
>> --- a/lib/librte_eal/common/include/rte_log.h
>> +++ b/lib/librte_eal/common/include/rte_log.h
>> @@ -20,6 +20,7 @@ extern "C" {
>>  #include <stdint.h>
>>  #include <stdio.h>
>>  #include <stdarg.h>
>> +#include <stdbool.h>
>>  #include <sys/queue.h>
>>
>>  #include <rte_common.h>
>> @@ -143,6 +144,19 @@ uint32_t rte_log_get_global_level(void);
>>   */
>>  int rte_log_get_level(uint32_t logtype);
>>
>> +/**
>> + * Check if a given `level` can be printed by a given `logtype`
> 
> The description is a bit odd to me.
> A "level" is not printed.
> A "logtype" does not print.

Agree, what about following, is it more clear:

"
For a given `logtype`, check if log with `loglevel` will be printed or not.
"

> 
> 
>> + *
>> + * @param logtype
>> + *   The log type identifier
>> + * @param level
>> + *   Log level. A value between RTE_LOG_EMERG (1) and RTE_LOG_DEBUG (8).
>> + * @return
>> + * Returns 'true' if log can be printed and 'false' if it can't.
>> + */
>> +__rte_experimental
>> +bool rte_log_can_log(uint32_t logtype, uint32_t level);
>> +
> 
> Would it make sense to actually change rte_log_get_level() to always
> take the global level into account?

Not sure, it can make 'rte_log_get_level()' confusing

> Then we would not introduce a new API, but this means deferring this
> patch to 20.11.

Apart from global level check, I think it is good to have this helper instead of
applications getting log level and comparing themselves, this API simplifies it.

> 
> 
> If we go with this helper, we can replace the check we have in rte_vlog:
> https://git.dpdk.org/dpdk/tree/lib/librte_eal/common/eal_common_log.c#n420

Right, why not, I can update in next version.

> 
> 
>>  /**
>>   * Set the log level for a given type based on shell pattern.
>>   *
>> diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
>> index 6cf507068..f9ede5b41 100644
>> --- a/lib/librte_eal/rte_eal_version.map
>> +++ b/lib/librte_eal/rte_eal_version.map
>> @@ -335,4 +335,7 @@ EXPERIMENTAL {
>>
>>         # added in 20.02
>>         rte_thread_is_intr;
>> +
>> +       # added in 20.05
>> +       rte_log_can_log;
>>  };
>> diff --git a/lib/librte_flow_classify/rte_flow_classify.c b/lib/librte_flow_classify/rte_flow_classify.c
>> index 5ff585803..6022064d8 100644
>> --- a/lib/librte_flow_classify/rte_flow_classify.c
>> +++ b/lib/librte_flow_classify/rte_flow_classify.c
>> @@ -417,7 +417,6 @@ static struct rte_flow_classify_rule *
>>  allocate_acl_ipv4_5tuple_rule(struct rte_flow_classifier *cls)
>>  {
>>         struct rte_flow_classify_rule *rule;
>> -       int log_level;
>>
>>         rule = malloc(sizeof(struct rte_flow_classify_rule));
>>         if (!rule)
>> @@ -466,9 +465,7 @@ allocate_acl_ipv4_5tuple_rule(struct rte_flow_classifier *cls)
>>                         cls->ntuple_filter.dst_port_mask;
>>         rule->rules.u.ipv4_5tuple.dst_port = cls->ntuple_filter.dst_port;
>>
>> -       log_level = rte_log_get_level(librte_flow_classify_logtype);
>> -
>> -       if (log_level == RTE_LOG_DEBUG)
>> +       if (rte_log_can_log(librte_flow_classify_logtype, RTE_LOG_DEBUG))
> 
> Idem, behavior change, but looks sane.
> 
> 
>>                 print_acl_ipv4_key_add(&rule->u.key.key_add);
>>
>>         /* key delete values */
>> @@ -476,7 +473,7 @@ allocate_acl_ipv4_5tuple_rule(struct rte_flow_classifier *cls)
>>                &rule->u.key.key_add.field_value[PROTO_FIELD_IPV4],
>>                NUM_FIELDS_IPV4 * sizeof(struct rte_acl_field));
>>
>> -       if (log_level == RTE_LOG_DEBUG)
>> +       if (rte_log_can_log(librte_flow_classify_logtype, RTE_LOG_DEBUG))
>>                 print_acl_ipv4_key_delete(&rule->u.key.key_del);
>>
>>         return rule;
>> --
>> 2.24.1
>>
> 
>