diff options
Diffstat (limited to 'net/mac80211/status.c')
| -rw-r--r-- | net/mac80211/status.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/net/mac80211/status.c b/net/mac80211/status.c index 52a152b01b0..1ee85c40243 100644 --- a/net/mac80211/status.c +++ b/net/mac80211/status.c @@ -11,6 +11,7 @@ #include <linux/export.h> #include <linux/etherdevice.h> +#include <linux/time.h> #include <net/mac80211.h> #include <asm/unaligned.h> #include "ieee80211_i.h" @@ -463,6 +464,77 @@ static void ieee80211_report_used_skb(struct ieee80211_local *local, } /* + * Measure Tx frame completion and removal time for Tx latency statistics + * calculation. A single Tx frame latency should be measured from when it + * is entering the Kernel until we receive Tx complete confirmation indication + * and remove the skb. + */ +static void ieee80211_tx_latency_end_msrmnt(struct ieee80211_local *local, + struct sk_buff *skb, + struct sta_info *sta, + struct ieee80211_hdr *hdr) +{ + ktime_t skb_dprt; + struct timespec dprt_time; + u32 msrmnt; + u16 tid; + u8 *qc; + int i, bin_range_count, bin_count; + u32 *bin_ranges; + __le16 fc; + struct ieee80211_tx_latency_stat *tx_lat; + struct ieee80211_tx_latency_bin_ranges *tx_latency; + ktime_t skb_arv = skb->tstamp; + + tx_latency = rcu_dereference(local->tx_latency); + + /* assert Tx latency stats are enabled & frame arrived when enabled */ + if (!tx_latency || !ktime_to_ns(skb_arv)) + return; + + fc = hdr->frame_control; + + if (!ieee80211_is_data(fc)) /* make sure it is a data frame */ + return; + + /* get frame tid */ + if (ieee80211_is_data_qos(hdr->frame_control)) { + qc = ieee80211_get_qos_ctl(hdr); + tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK; + } else { + tid = 0; + } + + tx_lat = &sta->tx_lat[tid]; + + ktime_get_ts(&dprt_time); /* time stamp completion time */ + skb_dprt = ktime_set(dprt_time.tv_sec, dprt_time.tv_nsec); + msrmnt = ktime_to_ms(ktime_sub(skb_dprt, skb_arv)); + + if (tx_lat->max < msrmnt) /* update stats */ + tx_lat->max = msrmnt; + tx_lat->counter++; + tx_lat->sum += msrmnt; + + if (!tx_lat->bins) /* bins not activated */ + return; + + /* count how many Tx frames transmitted with the appropriate latency */ + bin_range_count = tx_latency->n_ranges; + bin_ranges = tx_latency->ranges; + bin_count = tx_lat->bin_count; + + for (i = 0; i < bin_range_count; i++) { + if (msrmnt <= bin_ranges[i]) { + tx_lat->bins[i]++; + break; + } + } + if (i == bin_range_count) /* msrmnt is bigger than the biggest range */ + tx_lat->bins[i]++; +} + +/* * Use a static threshold for now, best value to be determined * by testing ... * Should it depend on: @@ -620,6 +692,12 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb) if (acked) sta->last_ack_signal = info->status.ack_signal; + + /* + * Measure frame removal for tx latency + * statistics calculation + */ + ieee80211_tx_latency_end_msrmnt(local, skb, sta, hdr); } rcu_read_unlock(); |