diff options
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/pie.h | 85 |
1 files changed, 58 insertions, 27 deletions
diff --git a/include/net/pie.h b/include/net/pie.h index ec0fbe98ec2f..51a1984c2dce 100644 --- a/include/net/pie.h +++ b/include/net/pie.h @@ -14,42 +14,74 @@ #define DQCOUNT_INVALID -1 #define PIE_SCALE 8 -/* parameters used */ +/** + * struct pie_params - contains pie parameters + * @target: target delay in pschedtime + * @tudpate: interval at which drop probability is calculated + * @limit: total number of packets that can be in the queue + * @alpha: parameter to control drop probability + * @beta: parameter to control drop probability + * @ecn: is ECN marking of packets enabled + * @bytemode: is drop probability scaled based on pkt size + * @dq_rate_estimator: is Little's law used for qdelay calculation + */ struct pie_params { - psched_time_t target; /* user specified target delay in pschedtime */ - u32 tupdate; /* timer frequency (in jiffies) */ - u32 limit; /* number of packets that can be enqueued */ - u32 alpha; /* alpha and beta are between 0 and 32 */ - u32 beta; /* and are used for shift relative to 1 */ - u8 ecn; /* true if ecn is enabled */ - u8 bytemode; /* to scale drop early prob based on pkt size */ - u8 dq_rate_estimator; /* to calculate delay using Little's law */ + psched_time_t target; + u32 tupdate; + u32 limit; + u32 alpha; + u32 beta; + u8 ecn; + u8 bytemode; + u8 dq_rate_estimator; }; -/* variables used */ +/** + * struct pie_vars - contains pie variables + * @qdelay: current queue delay + * @qdelay_old: queue delay in previous qdelay calculation + * @burst_time: burst time allowance + * @dq_tstamp: timestamp at which dq rate was last calculated + * @prob: drop probability + * @accu_prob: accumulated drop probability + * @dq_count: number of bytes dequeued in a measurement cycle + * @avg_dq_rate: calculated average dq rate + * @qlen_old: queue length during previous qdelay calculation + * @accu_prob_overflows: number of times accu_prob overflows + */ struct pie_vars { psched_time_t qdelay; psched_time_t qdelay_old; psched_time_t burst_time; - psched_time_t dq_tstamp; /* drain rate */ - u64 prob; /* probability but scaled by u64 limit. */ - u64 accu_prob; /* accumulated drop probability */ - u64 dq_count; /* measured in bytes */ - u32 avg_dq_rate; /* bytes per pschedtime tick,scaled */ - u32 qlen_old; /* in bytes */ - u8 accu_prob_overflows; /* overflows of accu_prob */ + psched_time_t dq_tstamp; + u64 prob; + u64 accu_prob; + u64 dq_count; + u32 avg_dq_rate; + u32 qlen_old; + u8 accu_prob_overflows; }; -/* statistics gathering */ +/** + * struct pie_stats - contains pie stats + * @packets_in: total number of packets enqueued + * @dropped: packets dropped due to pie action + * @overlimit: packets dropped due to lack of space in queue + * @ecn_mark: packets marked with ECN + * @maxq: maximum queue size + */ struct pie_stats { - u32 packets_in; /* total number of packets enqueued */ - u32 dropped; /* packets dropped due to pie_action */ - u32 overlimit; /* dropped due to lack of space in queue */ - u32 ecn_mark; /* packets marked with ECN */ - u32 maxq; /* maximum queue size */ + u32 packets_in; + u32 dropped; + u32 overlimit; + u32 ecn_mark; + u32 maxq; }; -/* private skb vars */ +/** + * struct pie_skb_cb - contains private skb vars + * @enqueue_time: timestamp when the packet is enqueued + */ struct pie_skb_cb { psched_time_t enqueue_time; }; @@ -58,7 +90,7 @@ static inline void pie_params_init(struct pie_params *params) { params->target = PSCHED_NS2TICKS(15 * NSEC_PER_MSEC); /* 15 ms */ params->tupdate = usecs_to_jiffies(15 * USEC_PER_MSEC); /* 15 ms */ - params->limit = 1000; /* default of 1000 packets */ + params->limit = 1000; params->alpha = 2; params->beta = 20; params->ecn = false; @@ -68,8 +100,7 @@ static inline void pie_params_init(struct pie_params *params) static inline void pie_vars_init(struct pie_vars *vars) { - /* default of 150 ms in pschedtime */ - vars->burst_time = PSCHED_NS2TICKS(150 * NSEC_PER_MSEC); + vars->burst_time = PSCHED_NS2TICKS(150 * NSEC_PER_MSEC); /* 150 ms */ vars->dq_tstamp = DTIME_INVALID; vars->accu_prob = 0; vars->dq_count = DQCOUNT_INVALID; |