From a5e8b5056ea8762e67c9fa980c8db48009ed2a67 Mon Sep 17 00:00:00 2001 From: Guy Cohen Date: Thu, 29 May 2008 16:35:11 +0800 Subject: [PATCH] iwlwifi: fix in-column rate scaling This patch fixes cases that the code raised or didn't decrease the rate although the success ratio was not good. Signed-off-by: Guy Cohen Signed-off-by: Tomas Winkler Signed-off-by: John W. Linville --- drivers/net/wireless/iwlwifi/iwl-4965-rs.c | 45 +++++++++++----------- 1 file changed, 23 insertions(+), 22 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-4965-rs.c b/drivers/net/wireless/iwlwifi/iwl-4965-rs.c index f28b3cc272..a89639f958 100644 --- a/drivers/net/wireless/iwlwifi/iwl-4965-rs.c +++ b/drivers/net/wireless/iwlwifi/iwl-4965-rs.c @@ -1336,7 +1336,7 @@ static int rs_move_legacy_other(struct iwl_priv *priv, lq_sta->search_better_tbl = 1; goto out; } - + break; case IWL_LEGACY_SWITCH_SISO: IWL_DEBUG_RATE("LQ: Legacy switch to SISO\n"); @@ -1422,9 +1422,9 @@ static int rs_move_siso_to_other(struct iwl_priv *priv, lq_sta->search_better_tbl = 1; goto out; } - + break; case IWL_SISO_SWITCH_MIMO2: - IWL_DEBUG_RATE("LQ: SISO switch to MIMO\n"); + IWL_DEBUG_RATE("LQ: SISO switch to MIMO2\n"); memcpy(search_tbl, tbl, sz); search_tbl->is_SGI = 0; search_tbl->ant_type = ANT_AB; /*FIXME:RS*/ @@ -1689,6 +1689,7 @@ static void rs_rate_scale_perform(struct iwl_priv *priv, u8 active_tbl = 0; u8 done_search = 0; u16 high_low; + s32 sr; #ifdef CONFIG_IWL4965_HT u8 tid = MAX_TID_COUNT; #endif @@ -1864,6 +1865,8 @@ static void rs_rate_scale_perform(struct iwl_priv *priv, low = high_low & 0xff; high = (high_low >> 8) & 0xff; + sr = window->success_ratio; + /* Collect measured throughputs for current and adjacent rates */ current_tpt = window->average_tpt; if (low != IWL_RATE_INVALID) @@ -1871,19 +1874,22 @@ static void rs_rate_scale_perform(struct iwl_priv *priv, if (high != IWL_RATE_INVALID) high_tpt = tbl->win[high].average_tpt; - /* Assume rate increase */ - scale_action = 1; + scale_action = 0; /* Too many failures, decrease rate */ - if ((window->success_ratio <= IWL_RATE_DECREASE_TH) || - (current_tpt == 0)) { + if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) { IWL_DEBUG_RATE("decrease rate because of low success_ratio\n"); scale_action = -1; /* No throughput measured yet for adjacent rates; try increase. */ } else if ((low_tpt == IWL_INVALID_VALUE) && - (high_tpt == IWL_INVALID_VALUE)) - scale_action = 1; + (high_tpt == IWL_INVALID_VALUE)) { + + if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH) + scale_action = 1; + else if (low != IWL_RATE_INVALID) + scale_action = -1; + } /* Both adjacent throughputs are measured, but neither one has better * throughput; we're using the best rate, don't change it! */ @@ -1899,9 +1905,10 @@ static void rs_rate_scale_perform(struct iwl_priv *priv, /* Higher adjacent rate's throughput is measured */ if (high_tpt != IWL_INVALID_VALUE) { /* Higher rate has better throughput */ - if (high_tpt > current_tpt) + if (high_tpt > current_tpt && + sr >= IWL_RATE_INCREASE_TH) { scale_action = 1; - else { + } else { IWL_DEBUG_RATE ("decrease rate because of high tpt\n"); scale_action = -1; @@ -1914,23 +1921,17 @@ static void rs_rate_scale_perform(struct iwl_priv *priv, IWL_DEBUG_RATE ("decrease rate because of low tpt\n"); scale_action = -1; - } else + } else if (sr >= IWL_RATE_INCREASE_TH) { scale_action = 1; + } } } /* Sanity check; asked for decrease, but success rate or throughput * has been good at old rate. Don't change it. */ - if (scale_action == -1) { - if ((low != IWL_RATE_INVALID) && - ((window->success_ratio > IWL_RATE_HIGH_TH) || + if ((scale_action == -1) && (low != IWL_RATE_INVALID) && + ((sr > IWL_RATE_HIGH_TH) || (current_tpt > (100 * tbl->expected_tpt[low])))) - scale_action = 0; - - /* Sanity check; asked for increase, but success rate has not been great - * even at old rate, higher rate will be worse. Don't change it. */ - } else if ((scale_action == 1) && - (window->success_ratio < IWL_RATE_INCREASE_TH)) scale_action = 0; switch (scale_action) { @@ -1959,7 +1960,7 @@ static void rs_rate_scale_perform(struct iwl_priv *priv, "high %d type %d\n", index, scale_action, low, high, tbl->lq_type); - lq_update: +lq_update: /* Replace uCode's rate table for the destination station. */ if (update_lq) { rate = rate_n_flags_from_tbl(tbl, index, is_green); -- 2.39.5