Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 170 insertions, 0 deletions

diff --git a/kernel/net/mac80211/rc80211_minstrel.h b/kernel/net/mac80211/rc80211_minstrel.h
new file mode 100644
index 000000000..c230bbe93
--- /dev/null
+++ b/kernel/net/mac80211/rc80211_minstrel.h
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __RC_MINSTREL_H
+#define __RC_MINSTREL_H
+
+#define EWMA_LEVEL	96	/* ewma weighting factor [/EWMA_DIV] */
+#define EWMA_DIV	128
+#define SAMPLE_COLUMNS	10	/* number of columns in sample table */
+
+/* scaled fraction values */
+#define MINSTREL_SCALE  16
+#define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
+#define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
+
+/* number of highest throughput rates to consider*/
+#define MAX_THR_RATES 4
+
+/*
+ * Perform EWMA (Exponentially Weighted Moving Average) calculation
+ */
+static inline int
+minstrel_ewma(int old, int new, int weight)
+{
+	int diff, incr;
+
+	diff = new - old;
+	incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
+
+	return old + incr;
+}
+
+/*
+ * Perform EWMSD (Exponentially Weighted Moving Standard Deviation) calculation
+ */
+static inline int
+minstrel_ewmsd(int old_ewmsd, int cur_prob, int prob_ewma, int weight)
+{
+	int diff, incr, tmp_var;
+
+	/* calculate exponential weighted moving variance */
+	diff = MINSTREL_TRUNC((cur_prob - prob_ewma) * 1000000);
+	incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
+	tmp_var = old_ewmsd * old_ewmsd;
+	tmp_var = weight * (tmp_var + diff * incr / 1000000) / EWMA_DIV;
+
+	/* return standard deviation */
+	return (u16) int_sqrt(tmp_var);
+}
+
+struct minstrel_rate_stats {
+	/* current / last sampling period attempts/success counters */
+	u16 attempts, last_attempts;
+	u16 success, last_success;
+
+	/* total attempts/success counters */
+	u64 att_hist, succ_hist;
+
+	/* statistis of packet delivery probability
+	 *  cur_prob  - current prob within last update intervall
+	 *  prob_ewma - exponential weighted moving average of prob
+	 *  prob_ewmsd - exp. weighted moving standard deviation of prob */
+	unsigned int cur_prob;
+	unsigned int prob_ewma;
+	u16 prob_ewmsd;
+
+	/* maximum retry counts */
+	u8 retry_count;
+	u8 retry_count_rtscts;
+
+	u8 sample_skipped;
+	bool retry_updated;
+};
+
+struct minstrel_rate {
+	int bitrate;
+
+	s8 rix;
+	u8 retry_count_cts;
+	u8 adjusted_retry_count;
+
+	unsigned int perfect_tx_time;
+	unsigned int ack_time;
+
+	int sample_limit;
+
+	struct minstrel_rate_stats stats;
+};
+
+struct minstrel_sta_info {
+	struct ieee80211_sta *sta;
+
+	unsigned long last_stats_update;
+	unsigned int sp_ack_dur;
+	unsigned int rate_avg;
+
+	unsigned int lowest_rix;
+
+	u8 max_tp_rate[MAX_THR_RATES];
+	u8 max_prob_rate;
+	unsigned int total_packets;
+	unsigned int sample_packets;
+	int sample_deferred;
+
+	unsigned int sample_row;
+	unsigned int sample_column;
+
+	int n_rates;
+	struct minstrel_rate *r;
+	bool prev_sample;
+
+	/* sampling table */
+	u8 *sample_table;
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+	struct dentry *dbg_stats;
+	struct dentry *dbg_stats_csv;
+#endif
+};
+
+struct minstrel_priv {
+	struct ieee80211_hw *hw;
+	bool has_mrr;
+	unsigned int cw_min;
+	unsigned int cw_max;
+	unsigned int max_retry;
+	unsigned int segment_size;
+	unsigned int update_interval;
+	unsigned int lookaround_rate;
+	unsigned int lookaround_rate_mrr;
+
+	u8 cck_rates[4];
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+	/*
+	 * enable fixed rate processing per RC
+	 *   - write static index to debugfs:ieee80211/phyX/rc/fixed_rate_idx
+	 *   - write -1 to enable RC processing again
+	 *   - setting will be applied on next update
+	 */
+	u32 fixed_rate_idx;
+	struct dentry *dbg_fixed_rate;
+#endif
+};
+
+struct minstrel_debugfs_info {
+	size_t len;
+	char buf[];
+};
+
+extern const struct rate_control_ops mac80211_minstrel;
+void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
+void minstrel_remove_sta_debugfs(void *priv, void *priv_sta);
+
+/* Recalculate success probabilities and counters for a given rate using EWMA */
+void minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs);
+int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma);
+
+/* debugfs */
+int minstrel_stats_open(struct inode *inode, struct file *file);
+int minstrel_stats_csv_open(struct inode *inode, struct file *file);
+ssize_t minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos);
+int minstrel_stats_release(struct inode *inode, struct file *file);
+
+#endif