[Codel] [PATCHv3 3/5] mac80211: add debug knobs for fair queuing
Michal Kazior
michal.kazior at tieto.com
Thu Apr 14 08:18:20 EDT 2016
This adds a few debugfs entries and a module
parameter to make it easier to test, debug and
experiment.
Signed-off-by: Michal Kazior <michal.kazior at tieto.com>
---
net/mac80211/debugfs.c | 77 +++++++++++++++++++++++++++++++++++++++++++
net/mac80211/debugfs_netdev.c | 28 +++++++++++++++-
net/mac80211/debugfs_sta.c | 45 +++++++++++++++++++++++++
net/mac80211/fq.h | 13 +++++++-
net/mac80211/fq_i.h | 7 ++++
net/mac80211/tx.c | 8 ++++-
6 files changed, 175 insertions(+), 3 deletions(-)
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 4ab5c522ceee..5cbaa5872e6b 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -31,6 +31,30 @@ int mac80211_format_buffer(char __user *userbuf, size_t count,
return simple_read_from_buffer(userbuf, count, ppos, buf, res);
}
+static int mac80211_parse_buffer(const char __user *userbuf,
+ size_t count,
+ loff_t *ppos,
+ char *fmt, ...)
+{
+ va_list args;
+ char buf[DEBUGFS_FORMAT_BUFFER_SIZE] = {};
+ int res;
+
+ if (count > sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(buf, userbuf, count))
+ return -EFAULT;
+
+ buf[sizeof(buf) - 1] = '\0';
+
+ va_start(args, fmt);
+ res = vsscanf(buf, fmt, args);
+ va_end(args);
+
+ return count;
+}
+
#define DEBUGFS_READONLY_FILE_FN(name, fmt, value...) \
static ssize_t name## _read(struct file *file, char __user *userbuf, \
size_t count, loff_t *ppos) \
@@ -70,6 +94,52 @@ DEBUGFS_READONLY_FILE(wep_iv, "%#08x",
DEBUGFS_READONLY_FILE(rate_ctrl_alg, "%s",
local->rate_ctrl ? local->rate_ctrl->ops->name : "hw/driver");
+#define DEBUGFS_RW_FILE_FN(name, expr) \
+static ssize_t name## _write(struct file *file, \
+ const char __user *userbuf, \
+ size_t count, \
+ loff_t *ppos) \
+{ \
+ struct ieee80211_local *local = file->private_data; \
+ return expr; \
+}
+
+#define DEBUGFS_RW_FILE(name, expr, fmt, value...) \
+ DEBUGFS_READONLY_FILE_FN(name, fmt, value) \
+ DEBUGFS_RW_FILE_FN(name, expr) \
+ DEBUGFS_RW_FILE_OPS(name)
+
+#define DEBUGFS_RW_FILE_OPS(name) \
+static const struct file_operations name## _ops = { \
+ .read = name## _read, \
+ .write = name## _write, \
+ .open = simple_open, \
+ .llseek = generic_file_llseek, \
+}
+
+#define DEBUGFS_RW_EXPR_FQ(args...) \
+({ \
+ int res; \
+ res = mac80211_parse_buffer(userbuf, count, ppos, args); \
+ res; \
+})
+
+DEBUGFS_READONLY_FILE(fq_flows_cnt, "%u",
+ local->fq.flows_cnt);
+DEBUGFS_READONLY_FILE(fq_backlog, "%u",
+ local->fq.backlog);
+DEBUGFS_READONLY_FILE(fq_overlimit, "%u",
+ local->fq.overlimit);
+DEBUGFS_READONLY_FILE(fq_collisions, "%u",
+ local->fq.collisions);
+
+DEBUGFS_RW_FILE(fq_limit,
+ DEBUGFS_RW_EXPR_FQ("%u", &local->fq.limit),
+ "%u", local->fq.limit);
+DEBUGFS_RW_FILE(fq_quantum,
+ DEBUGFS_RW_EXPR_FQ("%u", &local->fq.quantum),
+ "%u", local->fq.quantum);
+
#ifdef CONFIG_PM
static ssize_t reset_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
@@ -254,6 +324,13 @@ void debugfs_hw_add(struct ieee80211_local *local)
DEBUGFS_ADD(user_power);
DEBUGFS_ADD(power);
+ DEBUGFS_ADD(fq_flows_cnt);
+ DEBUGFS_ADD(fq_backlog);
+ DEBUGFS_ADD(fq_overlimit);
+ DEBUGFS_ADD(fq_collisions);
+ DEBUGFS_ADD(fq_limit);
+ DEBUGFS_ADD(fq_quantum);
+
statsd = debugfs_create_dir("statistics", phyd);
/* if the dir failed, don't put all the other things into the root! */
diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c
index 37ea30e0754c..471cab40a25f 100644
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -30,7 +30,7 @@ static ssize_t ieee80211_if_read(
size_t count, loff_t *ppos,
ssize_t (*format)(const struct ieee80211_sub_if_data *, char *, int))
{
- char buf[70];
+ char buf[200];
ssize_t ret = -EINVAL;
read_lock(&dev_base_lock);
@@ -236,6 +236,31 @@ ieee80211_if_fmt_hw_queues(const struct ieee80211_sub_if_data *sdata,
}
IEEE80211_IF_FILE_R(hw_queues);
+static ssize_t
+ieee80211_if_fmt_txq(const struct ieee80211_sub_if_data *sdata,
+ char *buf, int buflen)
+{
+ struct txq_info *txqi;
+ int len = 0;
+
+ if (!sdata->vif.txq)
+ return 0;
+
+ txqi = to_txq_info(sdata->vif.txq);
+ len += scnprintf(buf + len, buflen - len,
+ "CAB backlog %ub %up flows %u overlimit %u collisions %u tx %ub %up\n",
+ txqi->tin.backlog_bytes,
+ txqi->tin.backlog_packets,
+ txqi->tin.flows,
+ txqi->tin.overlimit,
+ txqi->tin.collisions,
+ txqi->tin.tx_bytes,
+ txqi->tin.tx_packets);
+
+ return len;
+}
+IEEE80211_IF_FILE_R(txq);
+
/* STA attributes */
IEEE80211_IF_FILE(bssid, u.mgd.bssid, MAC);
IEEE80211_IF_FILE(aid, u.mgd.aid, DEC);
@@ -618,6 +643,7 @@ static void add_common_files(struct ieee80211_sub_if_data *sdata)
DEBUGFS_ADD(rc_rateidx_vht_mcs_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_vht_mcs_mask_5ghz);
DEBUGFS_ADD(hw_queues);
+ DEBUGFS_ADD(txq);
}
static void add_sta_files(struct ieee80211_sub_if_data *sdata)
diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index a39512f09f9e..b5eb4f402710 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -319,6 +319,50 @@ static ssize_t sta_vht_capa_read(struct file *file, char __user *userbuf,
}
STA_OPS(vht_capa);
+static ssize_t sta_txqs_read(struct file *file,
+ char __user *userbuf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct sta_info *sta = file->private_data;
+ struct txq_info *txqi;
+ char *buf;
+ int buflen;
+ int len;
+ int res;
+ int i;
+
+ len = 0;
+ buflen = 200 * IEEE80211_NUM_TIDS;
+ buf = kzalloc(buflen, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
+ if (!sta->sta.txq[i])
+ break;
+
+ txqi = to_txq_info(sta->sta.txq[i]);
+ len += scnprintf(buf + len, buflen - len,
+ "TID %d AC %d backlog %ub %up flows %u overlimit %u collisions %u tx %ub %up\n",
+ i,
+ txqi->txq.ac,
+ txqi->tin.backlog_bytes,
+ txqi->tin.backlog_packets,
+ txqi->tin.flows,
+ txqi->tin.overlimit,
+ txqi->tin.collisions,
+ txqi->tin.tx_bytes,
+ txqi->tin.tx_packets);
+ }
+
+ res = simple_read_from_buffer(userbuf, count, ppos, buf, len);
+ kfree(buf);
+
+ return res;
+}
+STA_OPS(txqs);
+
#define DEBUGFS_ADD(name) \
debugfs_create_file(#name, 0400, \
@@ -365,6 +409,7 @@ void ieee80211_sta_debugfs_add(struct sta_info *sta)
DEBUGFS_ADD(agg_status);
DEBUGFS_ADD(ht_capa);
DEBUGFS_ADD(vht_capa);
+ DEBUGFS_ADD(txqs);
DEBUGFS_ADD_COUNTER(rx_duplicates, rx_stats.num_duplicates);
DEBUGFS_ADD_COUNTER(rx_fragments, rx_stats.fragments);
diff --git a/net/mac80211/fq.h b/net/mac80211/fq.h
index fa98576e1825..aa68363d6221 100644
--- a/net/mac80211/fq.h
+++ b/net/mac80211/fq.h
@@ -102,6 +102,8 @@ begin:
}
flow->deficit -= skb->len;
+ tin->tx_bytes += skb->len;
+ tin->tx_packets++;
return skb;
}
@@ -120,8 +122,14 @@ static struct fq_flow *fq_flow_classify(struct fq *fq,
idx = reciprocal_scale(hash, fq->flows_cnt);
flow = &fq->flows[idx];
- if (flow->tin && flow->tin != tin)
+ if (flow->tin && flow->tin != tin) {
flow = fq_flow_get_default_fn(fq, tin, idx, skb);
+ tin->collisions++;
+ fq->collisions++;
+ }
+
+ if (!flow->tin)
+ tin->flows++;
return flow;
}
@@ -174,6 +182,9 @@ static void fq_tin_enqueue(struct fq *fq,
return;
fq_skb_free_fn(fq, flow->tin, flow, skb);
+
+ flow->tin->overlimit++;
+ fq->overlimit++;
}
}
diff --git a/net/mac80211/fq_i.h b/net/mac80211/fq_i.h
index 5d8423f22e8d..0e25dda4fce3 100644
--- a/net/mac80211/fq_i.h
+++ b/net/mac80211/fq_i.h
@@ -51,6 +51,11 @@ struct fq_tin {
struct list_head old_flows;
u32 backlog_bytes;
u32 backlog_packets;
+ u32 overlimit;
+ u32 collisions;
+ u32 flows;
+ u32 tx_bytes;
+ u32 tx_packets;
};
/**
@@ -70,6 +75,8 @@ struct fq {
u32 limit;
u32 quantum;
u32 backlog;
+ u32 overlimit;
+ u32 collisions;
};
#endif
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index d4e0c87ecec5..396d0d17edeb 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
+#include <linux/moduleparam.h>
#include <linux/bitmap.h>
#include <linux/rcupdate.h>
#include <linux/export.h>
@@ -36,6 +37,11 @@
#include "rate.h"
#include "fq.h"
+static unsigned int fq_flows_cnt = 4096;
+module_param(fq_flows_cnt, uint, 0644);
+MODULE_PARM_DESC(fq_flows_cnt,
+ "Maximum number of txq fair queuing flows. ");
+
/* misc utils */
static inline void ieee80211_tx_stats(struct net_device *dev, u32 len)
@@ -1336,7 +1342,7 @@ int ieee80211_txq_setup_flows(struct ieee80211_local *local)
if (!local->ops->wake_tx_queue)
return 0;
- ret = fq_init(fq, 4096);
+ ret = fq_init(fq, max_t(u32, fq_flows_cnt, 1));
if (ret)
return ret;
--
2.1.4
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