Return-path: Received: from mail-lf0-f43.google.com ([209.85.215.43]:33934 "EHLO mail-lf0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752002AbcESIgG (ORCPT ); Thu, 19 May 2016 04:36:06 -0400 Received: by mail-lf0-f43.google.com with SMTP id m64so31604437lfd.1 for ; Thu, 19 May 2016 01:36:05 -0700 (PDT) From: Michal Kazior To: linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, dave.taht@gmail.com, make-wifi-fast@lists.bufferbloat.net, apenwarr@gmail.com, Michal Kazior Subject: [PATCHv5 3/5] mac80211: add debug knobs for fair queuing Date: Thu, 19 May 2016 10:37:50 +0200 Message-Id: <1463647072-16201-4-git-send-email-michal.kazior@tieto.com> (sfid-20160519_103618_084126_A402511F) In-Reply-To: <1463647072-16201-1-git-send-email-michal.kazior@tieto.com> References: <1462446039-1070-1-git-send-email-michal.kazior@tieto.com> <1463647072-16201-1-git-send-email-michal.kazior@tieto.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: This adds a debugfs entry to read and modify some fq parameters and inroduces a module parameter to control number of flows mac80211 shuold maintain. This makes it easy to debug, test and experiment. Signed-off-by: Michal Kazior --- Notes: v5: * expose a single "aqm" debugfs knob to maintain coherent stat values [Dave] net/mac80211/debugfs.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++ net/mac80211/tx.c | 8 ++- 2 files changed, 180 insertions(+), 1 deletion(-) diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index b251b2f7f8dd..2906c1004e1a 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -10,6 +10,7 @@ #include #include +#include #include "ieee80211_i.h" #include "driver-ops.h" #include "rate.h" @@ -70,6 +71,177 @@ DEBUGFS_READONLY_FILE(wep_iv, "%#08x", DEBUGFS_READONLY_FILE(rate_ctrl_alg, "%s", local->rate_ctrl ? local->rate_ctrl->ops->name : "hw/driver"); +struct aqm_info { + struct ieee80211_local *local; + size_t size; + size_t len; + unsigned char buf[0]; +}; + +#define AQM_HDR_LEN 200 +#define AQM_HW_ENTRY_LEN 40 +#define AQM_TXQ_ENTRY_LEN 110 + +static int aqm_open(struct inode *inode, struct file *file) +{ + struct ieee80211_local *local = inode->i_private; + struct ieee80211_sub_if_data *sdata; + struct sta_info *sta; + struct txq_info *txqi; + struct fq *fq = &local->fq; + struct aqm_info *info = NULL; + int len = 0; + int i; + + if (!local->ops->wake_tx_queue) + return -EOPNOTSUPP; + + len += AQM_HDR_LEN; + len += 6 * AQM_HW_ENTRY_LEN; + + rcu_read_lock(); + list_for_each_entry_rcu(sdata, &local->interfaces, list) + len += AQM_TXQ_ENTRY_LEN; + list_for_each_entry_rcu(sta, &local->sta_list, list) + len += AQM_TXQ_ENTRY_LEN * ARRAY_SIZE(sta->sta.txq); + rcu_read_unlock(); + + info = vmalloc(len); + if (!info) + return -ENOMEM; + + spin_lock_bh(&local->fq.lock); + rcu_read_lock(); + + file->private_data = info; + info->local = local; + info->size = len; + len = 0; + + len += scnprintf(info->buf + len, info->size - len, + "* hw\n" + "access name value\n" + "R fq_flows_cnt %u\n" + "R fq_backlog %u\n" + "R fq_overlimit %u\n" + "R fq_collisions %u\n" + "RW fq_limit %u\n" + "RW fq_quantum %u\n", + fq->flows_cnt, + fq->backlog, + fq->overlimit, + fq->collisions, + fq->limit, + fq->quantum); + + len += scnprintf(info->buf + len, + info->size - len, + "* vif\n" + "ifname addr ac backlog-bytes backlog-packets flows overlimit collisions tx-bytes tx-packets\n"); + + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + txqi = to_txq_info(sdata->vif.txq); + len += scnprintf(info->buf + len, info->size - len, + "%s %pM %u %u %u %u %u %u %u %u\n", + sdata->name, + sdata->vif.addr, + 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); + } + + len += scnprintf(info->buf + len, + info->size - len, + "* sta\n" + "ifname addr tid ac backlog-bytes backlog-packets flows overlimit collisions tx-bytes tx-packets\n"); + + list_for_each_entry_rcu(sta, &local->sta_list, list) { + sdata = sta->sdata; + for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) { + txqi = to_txq_info(sta->sta.txq[i]); + len += scnprintf(info->buf + len, info->size - len, + "%s %pM %d %d %u %u %u %u %u %u %u\n", + sdata->name, + sta->sta.addr, + txqi->txq.tid, + 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); + } + } + + info->len = len; + + rcu_read_unlock(); + spin_unlock_bh(&local->fq.lock); + + return 0; +} + +static int aqm_release(struct inode *inode, struct file *file) +{ + vfree(file->private_data); + return 0; +} + +static ssize_t aqm_read(struct file *file, + char __user *user_buf, + size_t count, + loff_t *ppos) +{ + struct aqm_info *info = file->private_data; + + return simple_read_from_buffer(user_buf, count, ppos, + info->buf, info->len); +} + +static ssize_t aqm_write(struct file *file, + const char __user *user_buf, + size_t count, + loff_t *ppos) +{ + struct aqm_info *info = file->private_data; + struct ieee80211_local *local = info->local; + char buf[100]; + size_t len; + + if (count > sizeof(buf)) + return -EINVAL; + + if (copy_from_user(buf, user_buf, count)) + return -EFAULT; + + buf[sizeof(buf) - 1] = '\0'; + len = strlen(buf); + if (len > 0 && buf[len-1] == '\n') + buf[len-1] = 0; + + if (sscanf(buf, "fq_limit %u", &local->fq.limit) == 1) + return count; + else if (sscanf(buf, "fq_quantum %u", &local->fq.quantum) == 1) + return count; + + return -EINVAL; +} + +static const struct file_operations aqm_ops = { + .write = aqm_write, + .read = aqm_read, + .open = aqm_open, + .release = aqm_release, + .llseek = default_llseek, +}; + #ifdef CONFIG_PM static ssize_t reset_write(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) @@ -256,6 +428,7 @@ void debugfs_hw_add(struct ieee80211_local *local) DEBUGFS_ADD(hwflags); DEBUGFS_ADD(user_power); DEBUGFS_ADD(power); + DEBUGFS_ADD_MODE(aqm, 0600); statsd = debugfs_create_dir("statistics", phyd); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 1d8343fca6d4..2b60b10e6990 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -36,6 +37,11 @@ #include "wme.h" #include "rate.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) @@ -1346,7 +1352,7 @@ 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