diff options
-rw-r--r-- | net/mac80211/debugfs.c | 168 | ||||
-rw-r--r-- | net/mac80211/debugfs_sta.c | 134 | ||||
-rw-r--r-- | net/mac80211/ieee80211_i.h | 24 | ||||
-rw-r--r-- | net/mac80211/main.c | 2 | ||||
-rw-r--r-- | net/mac80211/sta_info.c | 34 | ||||
-rw-r--r-- | net/mac80211/sta_info.h | 22 | ||||
-rw-r--r-- | net/mac80211/status.c | 78 | ||||
-rw-r--r-- | net/mac80211/tx.c | 24 |
8 files changed, 486 insertions, 0 deletions
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index 5c090e4..fa16e54 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -17,6 +17,172 @@ #define DEBUGFS_FORMAT_BUFFER_SIZE 100 +#define TX_LATENCY_BIN_DELIMTER_C ',' +#define TX_LATENCY_BIN_DELIMTER_S "," +#define TX_LATENCY_BINS_DISABLED "enable(bins disabled)\n" +#define TX_LATENCY_DISABLED "disable\n" + + +/* + * Display if Tx latency statistics & bins are enabled/disabled + */ +static ssize_t sta_tx_latency_stat_read(struct file *file, + char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct ieee80211_local *local = file->private_data; + struct ieee80211_tx_latency_bin_ranges *tx_latency; + char *buf; + int bufsz, i, ret; + int pos = 0; + + rcu_read_lock(); + + tx_latency = rcu_dereference(local->tx_latency); + + if (tx_latency && tx_latency->n_ranges) { + bufsz = tx_latency->n_ranges * 15; + buf = kzalloc(bufsz, GFP_ATOMIC); + if (!buf) + goto err; + + for (i = 0; i < tx_latency->n_ranges; i++) + pos += scnprintf(buf + pos, bufsz - pos, "%d,", + tx_latency->ranges[i]); + pos += scnprintf(buf + pos, bufsz - pos, "\n"); + } else if (tx_latency) { + bufsz = sizeof(TX_LATENCY_BINS_DISABLED) + 1; + buf = kzalloc(bufsz, GFP_ATOMIC); + if (!buf) + goto err; + + pos += scnprintf(buf + pos, bufsz - pos, "%s\n", + TX_LATENCY_BINS_DISABLED); + } else { + bufsz = sizeof(TX_LATENCY_DISABLED) + 1; + buf = kzalloc(bufsz, GFP_ATOMIC); + if (!buf) + goto err; + + pos += scnprintf(buf + pos, bufsz - pos, "%s\n", + TX_LATENCY_DISABLED); + } + + rcu_read_unlock(); + + ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos); + kfree(buf); + + return ret; +err: + rcu_read_unlock(); + return -ENOMEM; +} + +/* + * Receive input from user regarding Tx latency statistics + * The input should indicate if Tx latency statistics and bins are + * enabled/disabled. + * If bins are enabled input should indicate the amount of different bins and + * their ranges. Each bin will count how many Tx frames transmitted within the + * appropriate latency. + * Legal input is: + * a) "enable(bins disabled)" - to enable only general statistics + * b) "a,b,c,d,...z" - to enable general statistics and bins, where all are + * numbers and a < b < c < d.. < z + * c) "disable" - disable all statistics + * NOTE: must configure Tx latency statistics bins before stations connected. + */ + +static ssize_t sta_tx_latency_stat_write(struct file *file, + const char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct ieee80211_local *local = file->private_data; + char buf[128] = {}; + char *bins = buf; + char *token; + int buf_size, i, alloc_size; + int prev_bin = 0; + int n_ranges = 0; + int ret = count; + struct ieee80211_tx_latency_bin_ranges *tx_latency; + + if (sizeof(buf) <= count) + return -EINVAL; + buf_size = count; + if (copy_from_user(buf, userbuf, buf_size)) + return -EFAULT; + + mutex_lock(&local->sta_mtx); + + /* cannot change config once we have stations */ + if (local->num_sta) + goto unlock; + + tx_latency = + rcu_dereference_protected(local->tx_latency, + lockdep_is_held(&local->sta_mtx)); + + /* disable Tx statistics */ + if (!strcmp(buf, TX_LATENCY_DISABLED)) { + if (!tx_latency) + goto unlock; + rcu_assign_pointer(local->tx_latency, NULL); + synchronize_rcu(); + kfree(tx_latency); + goto unlock; + } + + /* Tx latency already enabled */ + if (tx_latency) + goto unlock; + + if (strcmp(TX_LATENCY_BINS_DISABLED, buf)) { + /* check how many bins and between what ranges user requested */ + token = buf; + while (*token != '\0') { + if (*token == TX_LATENCY_BIN_DELIMTER_C) + n_ranges++; + token++; + } + n_ranges++; + } + + alloc_size = sizeof(struct ieee80211_tx_latency_bin_ranges) + + n_ranges * sizeof(u32); + tx_latency = kzalloc(alloc_size, GFP_ATOMIC); + if (!tx_latency) { + ret = -ENOMEM; + goto unlock; + } + tx_latency->n_ranges = n_ranges; + for (i = 0; i < n_ranges; i++) { /* setting bin ranges */ + token = strsep(&bins, TX_LATENCY_BIN_DELIMTER_S); + sscanf(token, "%d", &tx_latency->ranges[i]); + /* bins values should be in ascending order */ + if (prev_bin >= tx_latency->ranges[i]) { + ret = -EINVAL; + kfree(tx_latency); + goto unlock; + } + prev_bin = tx_latency->ranges[i]; + } + rcu_assign_pointer(local->tx_latency, tx_latency); + +unlock: + mutex_unlock(&local->sta_mtx); + + return ret; +} + +static const struct file_operations stats_tx_latency_ops = { + .write = sta_tx_latency_stat_write, + .read = sta_tx_latency_stat_read, + .open = simple_open, + .llseek = generic_file_llseek, +}; + int mac80211_format_buffer(char __user *userbuf, size_t count, loff_t *ppos, char *fmt, ...) { @@ -315,4 +481,6 @@ void debugfs_hw_add(struct ieee80211_local *local) DEBUGFS_DEVSTATS_ADD(dot11RTSFailureCount); DEBUGFS_DEVSTATS_ADD(dot11FCSErrorCount); DEBUGFS_DEVSTATS_ADD(dot11RTSSuccessCount); + + DEBUGFS_DEVSTATS_ADD(tx_latency); } diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c index 19c54a4..80194b5 100644 --- a/net/mac80211/debugfs_sta.c +++ b/net/mac80211/debugfs_sta.c @@ -38,6 +38,13 @@ static const struct file_operations sta_ ##name## _ops = { \ .llseek = generic_file_llseek, \ } +#define STA_OPS_W(name) \ +static const struct file_operations sta_ ##name## _ops = { \ + .write = sta_##name##_write, \ + .open = simple_open, \ + .llseek = generic_file_llseek, \ +} + #define STA_OPS_RW(name) \ static const struct file_operations sta_ ##name## _ops = { \ .read = sta_##name##_read, \ @@ -388,6 +395,131 @@ static ssize_t sta_last_rx_rate_read(struct file *file, char __user *userbuf, } STA_OPS(last_rx_rate); +static int +sta_tx_latency_stat_header(struct ieee80211_tx_latency_bin_ranges *tx_latency, + char *buf, int pos, int bufsz) +{ + int i; + int range_count = tx_latency->n_ranges; + u32 *bin_ranges = tx_latency->ranges; + + pos += scnprintf(buf + pos, bufsz - pos, + "Station\t\t\tTID\tMax\tAvg"); + if (range_count) { + pos += scnprintf(buf + pos, bufsz - pos, + "\t<=%d", bin_ranges[0]); + for (i = 0; i < range_count - 1; i++) + pos += scnprintf(buf + pos, bufsz - pos, "\t%d-%d", + bin_ranges[i], bin_ranges[i+1]); + pos += scnprintf(buf + pos, bufsz - pos, + "\t%d<", bin_ranges[range_count - 1]); + } + + pos += scnprintf(buf + pos, bufsz - pos, "\n"); + + return pos; +} + +static int +sta_tx_latency_stat_table(struct ieee80211_tx_latency_bin_ranges *tx_lat_range, + struct ieee80211_tx_latency_stat *tx_lat, + char *buf, int pos, int bufsz, int tid) +{ + u32 avg = 0; + int j; + int bin_count = tx_lat->bin_count; + + pos += scnprintf(buf + pos, bufsz - pos, "\t\t\t%d", tid); + /* make sure you don't divide in 0 */ + if (tx_lat->counter) + avg = tx_lat->sum / tx_lat->counter; + + pos += scnprintf(buf + pos, bufsz - pos, "\t%d\t%d", + tx_lat->max, avg); + + if (tx_lat_range->n_ranges && tx_lat->bins) + for (j = 0; j < bin_count; j++) + pos += scnprintf(buf + pos, bufsz - pos, + "\t%d", tx_lat->bins[j]); + pos += scnprintf(buf + pos, bufsz - pos, "\n"); + + return pos; +} + +/* + * Output Tx latency statistics station && restart all statistics information + */ +static ssize_t sta_tx_latency_stat_read(struct file *file, + char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct sta_info *sta = file->private_data; + struct ieee80211_local *local = sta->local; + struct ieee80211_tx_latency_bin_ranges *tx_latency; + char *buf; + int bufsz, ret, i; + int pos = 0; + + bufsz = 20 * IEEE80211_NUM_TIDS * + sizeof(struct ieee80211_tx_latency_stat); + buf = kzalloc(bufsz, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + rcu_read_lock(); + + tx_latency = rcu_dereference(local->tx_latency); + + if (!sta->tx_lat) { + pos += scnprintf(buf + pos, bufsz - pos, + "Tx latency statistics are not enabled\n"); + goto unlock; + } + + pos = sta_tx_latency_stat_header(tx_latency, buf, pos, bufsz); + + pos += scnprintf(buf + pos, bufsz - pos, "%pM\n", sta->sta.addr); + for (i = 0; i < IEEE80211_NUM_TIDS; i++) + pos = sta_tx_latency_stat_table(tx_latency, &sta->tx_lat[i], + buf, pos, bufsz, i); +unlock: + rcu_read_unlock(); + + ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos); + kfree(buf); + + return ret; +} +STA_OPS(tx_latency_stat); + +static ssize_t sta_tx_latency_stat_reset_write(struct file *file, + const char __user *userbuf, + size_t count, loff_t *ppos) +{ + u32 *bins; + int bin_count; + struct sta_info *sta = file->private_data; + int i; + + if (!sta->tx_lat) + return -EINVAL; + + for (i = 0; i < IEEE80211_NUM_TIDS; i++) { + bins = sta->tx_lat[i].bins; + bin_count = sta->tx_lat[i].bin_count; + + sta->tx_lat[i].max = 0; + sta->tx_lat[i].sum = 0; + sta->tx_lat[i].counter = 0; + + if (bin_count) + memset(bins, 0, bin_count * sizeof(u32)); + } + + return count; +} +STA_OPS_W(tx_latency_stat_reset); + #define DEBUGFS_ADD(name) \ debugfs_create_file(#name, 0400, \ sta->debugfs.dir, sta, &sta_ ##name## _ops); @@ -441,6 +573,8 @@ void ieee80211_sta_debugfs_add(struct sta_info *sta) DEBUGFS_ADD(last_ack_signal); DEBUGFS_ADD(current_tx_rate); DEBUGFS_ADD(last_rx_rate); + DEBUGFS_ADD(tx_latency_stat); + DEBUGFS_ADD(tx_latency_stat_reset); DEBUGFS_ADD_COUNTER(rx_packets, rx_packets); DEBUGFS_ADD_COUNTER(tx_packets, tx_packets); diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 4022ee1..834f0eb 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -898,6 +898,24 @@ struct tpt_led_trigger { }; #endif +/* + * struct ieee80211_tx_latency_bin_ranges - Tx latency statistics bins ranges + * + * Measuring Tx latency statistics. Counts how many Tx frames transmitted in a + * certain latency range (in Milliseconds). Each station that uses these + * ranges will have bins to count the amount of frames received in that range. + * The user can configure the ranges via debugfs. + * If ranges is NULL then Tx latency statistics bins are disabled for all + * stations. + * + * @n_ranges: number of ranges that are taken in account + * @ranges: the ranges that the user requested or NULL if disabled. + */ +struct ieee80211_tx_latency_bin_ranges { + int n_ranges; + u32 ranges[]; +}; + /** * mac80211 scan flags - currently active scan mode * @@ -1050,6 +1068,12 @@ struct ieee80211_local { struct timer_list sta_cleanup; int sta_generation; + /* + * Tx latency statistics parameters for all stations. + * Can enable via debugfs (NULL when disabled). + */ + struct ieee80211_tx_latency_bin_ranges __rcu *tx_latency; + struct sk_buff_head pending[IEEE80211_MAX_QUEUES]; struct tasklet_struct tx_pending_tasklet; diff --git a/net/mac80211/main.c b/net/mac80211/main.c index bdb0b6c..8af75f0 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -1142,6 +1142,8 @@ void ieee80211_free_hw(struct ieee80211_hw *hw) ieee80211_free_ack_frame, NULL); idr_destroy(&local->ack_status_frames); + kfree(rcu_access_pointer(local->tx_latency)); + wiphy_free(local->hw.wiphy); } EXPORT_SYMBOL(ieee80211_free_hw); diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 7b69d4c..8ed97f7 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -266,9 +266,17 @@ struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata, */ void sta_info_free(struct ieee80211_local *local, struct sta_info *sta) { + int i; + if (sta->rate_ctrl) rate_control_free_sta(sta); + if (sta->tx_lat) { + for (i = 0; i < IEEE80211_NUM_TIDS; i++) + kfree(sta->tx_lat[i].bins); + kfree(sta->tx_lat); + } + sta_dbg(sta->sdata, "Destroyed STA %pM\n", sta->sta.addr); kfree(sta); @@ -333,6 +341,7 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, struct ieee80211_local *local = sdata->local; struct sta_info *sta; struct timespec uptime; + struct ieee80211_tx_latency_bin_ranges *tx_latency; int i; sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); @@ -410,6 +419,31 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, } } + rcu_read_lock(); + + tx_latency = rcu_dereference(local->tx_latency); + /* init stations Tx latency statistics && TID bins */ + if (tx_latency) + sta->tx_lat = kzalloc(IEEE80211_NUM_TIDS * + sizeof(struct ieee80211_tx_latency_stat), + GFP_ATOMIC); + + /* + * if Tx latency and bins are enabled and the previous allocation + * succeeded + */ + if (tx_latency && tx_latency->n_ranges && sta->tx_lat) + for (i = 0; i < IEEE80211_NUM_TIDS; i++) { + /* size of bins is size of the ranges +1 */ + sta->tx_lat[i].bin_count = + tx_latency->n_ranges + 1; + sta->tx_lat[i].bins = kcalloc(sta->tx_lat[i].bin_count, + sizeof(u32), + GFP_ATOMIC); + } + + rcu_read_unlock(); + sta_dbg(sdata, "Allocated STA %pM\n", sta->sta.addr); return sta; diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index a2c9a4c..0218caf 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -220,6 +220,25 @@ struct sta_ampdu_mlme { u8 dialog_token_allocator; }; +/* + * struct ieee80211_tx_latency_stat - Tx latency statistics + * + * Measures TX latency and jitter for a station per TID. + * + * @max: worst case latency + * @sum: sum of all latencies + * @counter: amount of Tx frames sent from interface + * @bins: each bin counts how many frames transmitted within a certain + * latency range. when disabled it is NULL. + * @bin_count: amount of bins. + */ +struct ieee80211_tx_latency_stat { + u32 max; + u32 sum; + u32 counter; + u32 *bins; + u32 bin_count; +}; /** * struct sta_info - STA information @@ -276,6 +295,7 @@ struct sta_ampdu_mlme { * @tid_seq: per-TID sequence numbers for sending to this STA * @ampdu_mlme: A-MPDU state machine state * @timer_to_tid: identity mapping to ID timers + * @tx_lat: Tx latency statistics * @llid: Local link ID * @plid: Peer link ID * @reason: Cancel reason on PLINK_HOLDING state @@ -385,6 +405,8 @@ struct sta_info { struct sta_ampdu_mlme ampdu_mlme; u8 timer_to_tid[IEEE80211_NUM_TIDS]; + struct ieee80211_tx_latency_stat *tx_lat; + #ifdef CONFIG_MAC80211_MESH /* * Mesh peer link attributes diff --git a/net/mac80211/status.c b/net/mac80211/status.c index 52a152b..1ee85c4 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(); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index e541856..6d59e21 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -19,6 +19,7 @@ #include <linux/bitmap.h> #include <linux/rcupdate.h> #include <linux/export.h> +#include <linux/time.h> #include <net/net_namespace.h> #include <net/ieee80211_radiotap.h> #include <net/cfg80211.h> @@ -1741,6 +1742,26 @@ fail: return NETDEV_TX_OK; /* meaning, we dealt with the skb */ } +/* + * Measure Tx frame arrival 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 the skb is + * freed. + */ +static void ieee80211_tx_latency_start_msrmnt(struct ieee80211_local *local, + struct sk_buff *skb) +{ + struct timespec skb_arv; + struct ieee80211_tx_latency_bin_ranges *tx_latency; + + tx_latency = rcu_dereference(local->tx_latency); + if (!tx_latency) + return; + + ktime_get_ts(&skb_arv); + skb->tstamp = ktime_set(skb_arv.tv_sec, skb_arv.tv_nsec); +} + /** * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type * subinterfaces (wlan#, WDS, and VLAN interfaces) @@ -1791,6 +1812,9 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, rcu_read_lock(); + /* Measure frame arrival for Tx latency statistics calculation */ + ieee80211_tx_latency_start_msrmnt(local, skb); + switch (sdata->vif.type) { case NL80211_IFTYPE_AP_VLAN: sta = rcu_dereference(sdata->u.vlan.sta); |