From 6b8f85a9188321e59995d172efab9e97afd3906f Mon Sep 17 00:00:00 2001 From: Nick Kossifidis Date: Wed, 29 Apr 2015 23:51:19 +0000 Subject: [PATCH] ath9k: Skip FFT reports if we are out of output buffers There is no reason to keep processing FFT reports if there is no space left on the relayfs buffers for the results. This saves lots of CPU cycles, especially on normal (non-short) reports. Signed-off-by: Nick Kossifidis Signed-off-by: Kalle Valo --- .../net/wireless/ath/ath9k/common-spectral.c | 28 +++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/net/wireless/ath/ath9k/common-spectral.c b/drivers/net/wireless/ath/ath9k/common-spectral.c index b8682bc4f7ac..4ab08edeb065 100644 --- a/drivers/net/wireless/ath/ath9k/common-spectral.c +++ b/drivers/net/wireless/ath/ath9k/common-spectral.c @@ -473,6 +473,24 @@ ath_cmn_copy_fft_frame(u8 *in, u8 *out, int sample_len, int sample_bytes) } } +static int +ath_cmn_is_fft_buf_full(struct ath_spec_scan_priv *spec_priv) +{ + int i = 0; + int ret = 0; + struct rchan *rc = spec_priv->rfs_chan_spec_scan; + + for_each_online_cpu(i) + ret += relay_buf_full(rc->buf[i]); + + i = num_online_cpus(); + + if (ret == i) + return 1; + else + return 0; +} + /* returns 1 if this was a spectral frame, even if not handled. */ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_hdr *hdr, struct ath_rx_status *rs, u64 tsf) @@ -509,6 +527,16 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h if (!(radar_info->pulse_bw_info & SPECTRAL_SCAN_BITMASK)) return 0; + /* Output buffers are full, no need to process anything + * since there is no space to put the result anyway + */ + ret = ath_cmn_is_fft_buf_full(spec_priv); + if (ret == 1) { + ath_dbg(common, SPECTRAL_SCAN, "FFT report ignored, no space " + "left on output buffers\n"); + return 1; + } + chan_type = cfg80211_get_chandef_type(&common->hw->conf.chandef); if ((chan_type == NL80211_CHAN_HT40MINUS) || (chan_type == NL80211_CHAN_HT40PLUS)) {