Quick DPDK log

1.DPDK log level
#define RTE_LOG_EMERG 1U /**< System is unusable. */
#define RTE_LOG_ALERT 2U /**< Action must be taken immediately. */
#define RTE_LOG_CRIT 3U /**< Critical conditions. */
#define RTE_LOG_ERR 4U /**< Error conditions. */
#define RTE_LOG_WARNING 5U /**< Warning conditions. */
#define RTE_LOG_NOTICE 6U /**< Normal but significant condition. */
#define RTE_LOG_INFO 7U /**< Informational. */
#define RTE_LOG_DEBUG 8U /**< Debug-level messages. */

rte_set_log_level(); 

eg：rte_set_log_level(RTE_LOG_DEBUG    );  

rte_set_log_level() was called inside rte_eal_init()

2.DPDK log types

defined in "./liblibrte_eal/common/include/rte_log.h"：

#define RTE_LOGTYPE_EAL 0x00000001 /**< Log related to eal. */
#define RTE_LOGTYPE_MALLOC 0x00000002 /**< Log related to malloc. */
#define RTE_LOGTYPE_RING 0x00000004 /**< Log related to ring. */
#define RTE_LOGTYPE_MEMPOOL 0x00000008 /**< Log related to mempool. */
#define RTE_LOGTYPE_TIMER 0x00000010 /**< Log related to timers. */
#define RTE_LOGTYPE_PMD 0x00000020 /**< Log related to poll mode driver. */
#define RTE_LOGTYPE_HASH 0x00000040 /**< Log related to hash table. */
#define RTE_LOGTYPE_LPM 0x00000080 /**< Log related to LPM. */
#define RTE_LOGTYPE_KNI 0x00000100 /**< Log related to KNI. */
#define RTE_LOGTYPE_ACL 0x00000200 /**< Log related to ACL. */
#define RTE_LOGTYPE_POWER 0x00000400 /**< Log related to power. */
#define RTE_LOGTYPE_METER 0x00000800 /**< Log related to QoS meter. */
#define RTE_LOGTYPE_SCHED 0x00001000 /**< Log related to QoS port scheduler. */
#define RTE_LOGTYPE_PORT 0x00002000 /**< Log related to port. */
#define RTE_LOGTYPE_TABLE 0x00004000 /**< Log related to table. */
#define RTE_LOGTYPE_PIPELINE 0x00008000 /**< Log related to pipeline. */

/* these log types can be used in an application */
#define RTE_LOGTYPE_USER1 0x01000000 /**< User-defined log type 1. */
#define RTE_LOGTYPE_USER2 0x02000000 /**< User-defined log type 2. */
#define RTE_LOGTYPE_USER3 0x04000000 /**< User-defined log type 3. */
#define RTE_LOGTYPE_USER4 0x08000000 /**< User-defined log type 4. */
#define RTE_LOGTYPE_USER5 0x10000000 /**< User-defined log type 5. */
#define RTE_LOGTYPE_USER6 0x20000000 /**< User-defined log type 6. */
#define RTE_LOGTYPE_USER7 0x40000000 /**< User-defined log type 7. */
#define RTE_LOGTYPE_USER8 0x80000000 /**< User-defined log type 8. */

3. support syslog
configuration in syslog.conf

4. eal command line option
--log-level
eg： ./build/l2fwd -c 3 -n 4  --log-level  8  

5. log example code
  File *my_log = fopen("./my_log.txt", "a");
  rte_openlog_stream(my_log);
  rte_log_set_global_level(RTE_LOG_WARNING);
  RTE_LOG(ERR, USER8, "my test log, id: %d\n", 1688);