ath9k currently forces hw->max_rate_tries to 4 to work around rate
control inefficiencies. This has some negative side effects, such as
rate_control_send_low also using a maximum of 4 tries, which could
negatively affect reliability of unicast management frames.
This patch pushes the retry limit to the rate control instead, and
allows it to use more tries on the last stage to prevent unnecessary
packet loss.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Atheros single stream AR9285 and AR9271 have half the PCU TX FIFO
buffer size of that of dual stream devices. Dual stream devices
have a max PCU TX FIFO size of 8 KB while single stream devices
have 4 KB. Single stream devices have an issue though and require
hardware only to use half of the amount of its capable PCU TX FIFO
size, 2 KB and this requires a change in software.
Technically a change would not have been required (except for frame
burst considerations of 128 bytes) if these devices would have been
able to use the full 4 KB of the PCU TX FIFO size but our systems
engineers recommend 2 KB to be used only. We enforce this through
software by reducing the max frame triggger level to 2 KB.
Fixing the max frame trigger level should then have a few benefits:
* The PER will now be adjusted as designed for underruns when the
max trigger level is reached. This should help alleviate the
bus as the rate control algorithm chooses a slower rate which
should ensure frames are transmitted properly under high system
bus load.
* The poll we use on our TX queues should now trigger and work
as designed for single stream devices. The hardware passes
data from each TX queue on the PCU TX FIFO queue respecting each
queue's priority. The new trigger level ensures this seeding of
the PCU TX FIFO queue occurs as designed which could mean avoiding
false resets and actually reseting hw correctly when a TX queue
is indeed stuck.
* Some undocumented / unsupported behaviour could have been triggered
when the max trigger level level was being set to 4 KB on single
stream devices. Its not clear what this issue was to me yet.
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Cc: Bennyam Malavazi <bennyam.malavazi@atheros.com>
Cc: Stephen Chen <stephen.chen@atheros.com>
Cc: Shan Palanisamy <shan.palanisamy@atheros.com>
Cc: Paul Shaw <paul.shaw@atheros.com>
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Remove some fields from struct ath_rate_table that are now unused.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch changes ath9k to pass proper MCS indexes and flags
between the RC and the rest of the driver code.
sc->cur_rate_table remains, as it's used by the RC code internally,
but the rest of the driver code no longer uses it, so a potential
new RC for ath9k would not have to update it.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The entire aggregation code currently operates on the
hw pointer and station addresses, but that needs to
change to make stations purely per-vif; As one step
preparing for that make the aggregation code callable
with the station, or by the combination of virtual
interface and station address.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch removes the need for separately allocated private tx info
data in ath9k and brings the driver one small step closer to using the
mac80211 rate control API properly.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Conflicts:
drivers/net/usb/cdc_ether.c
All CDC ethernet devices of type USB_CLASS_COMM need to use
'&mbm_info'.
Signed-off-by: David S. Miller <davem@davemloft.net>
The patch e43419f9:
ath9k: downgrade assert in rc.c for invalid rate
downgraded an ASSERT to a WARN_ON() but also misplaced a
semicolon at the end of the second check. What this did
was force the rate control code to always return the rate
even if we should have warned about it. Since this should
not have happened anymore anyway this fix isn't critical
as the proper rate would have been returned anyway.
Cc: stable@kernel.org
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ath9k uses this for now, ath9k_htc is expected to re-use this
as well. We lave ath5k as is, but it certainly can also be
converted later.
The ath9k module parameter and debugfs entry is kept.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
DPRINTF() is used in hw specific related code, as such
ensure we don't rely on the private driver core ath_softc
struct when calling it. Drivers can then implement their
own DPRINTF() as they see fit.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Monotonicity of packet error rate should be kept when moving
from one phy to another (legacy to ht, ht single stream to dual,
etc). Current code skips updating per for other phys.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Now the lowest rate in 11na ht40 mode is 13.5Mbps this shortens the
range when compared to 11na ht20 mode where the lowest rate is 6.5Mbps.
To improve the range, make 6.5Mbps as the lowest rate in 11na ht40 mode,
this improves the range by approximately 2dB. 11ng ht40 does not have
this issue as it also has basic rates (1, 2, 5.5 and 11).
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Move its only member (u8 per) to struct ath_rate_priv.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Get rid of rssi reduce interval.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ath9k rate control is based on only PER (packet error rate),
remove unused code which was intented to do rssi based rate
selection.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
After the cleanup we just use get_rate as a wrapper, skip
the wrapper.
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
All current rate control algorithms agree to send management and no-ack
frames at the lowest rate. They also agree to do this when sta
and the private rate control data is NULL. We add a hlper to mac80211
for this and simplify the rate control algorithm code.
Developers wishing to make enhancements to rate control algorithms
are for broadcast/multicast can opt to not use this in their
gate_rate() mac80211 callback.
Cc: Zhu Yi <yi.zhu@intel.com>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: ipw3945-devel@lists.sourceforge.net
Cc: Gabor Juhos <juhosg@openwrt.org>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
We check for this condition early on in our mac80211 get_rate()
callback ath_get_rate(), so remove this check later down the path.
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The purpose is to find the highest rate we can use.
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This saves us 2733 bytes.
text data bss dec hex filename
252265 3628 1584 257477 3edc5 ath9k-has-b-rate.ko
249905 3628 1584 255117 3e48d ath9k.ko
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Siged-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
What this does is get us our next lower rate so call it that,
ath_rc_get_lower_rix().
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is just calling another helper, so just use the other
helper directly. This should make it clear that when do not
find the next rate we stick to the current one.
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is not used, remove this.
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is not used, and when we need to get the lowest rate
we should simply use mac80211's own rate_lowest_index(sband, sta).
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This has no functional change and just cleans up the code
to be more legible and removes a useless variable for
Multi Rate Retry.
For regular frames we use 2 retries for MRR segments [0-2].
For the last MRR segment [3] we use 4.
MRR[0] = 2
MRR[1] = 2
MRR[2] = 2
MRR[3] = 4
Cc: Derek Smithies <derek@indranet.co.nz>
Cc: Chittajit Mitra <Chittajit.Mitra@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The case where no vaid rate is found should not happen now
but to help debugging and downgrade this to a warn.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
On x86 this allows us to do the following small savings:
shave off 23 % off of the module's data, and
shave off 6 % off of the module's text.
We save 456 bytes, for those counting.
$ size ath9k.ko
text data bss dec hex filename
250794 3628 1600 256022 3e816 ath9k.ko
$ size ath9k-old.ko
text data bss dec hex filename
239114 15308 1600 256022 3e816 ath9k-old.ko
$ du -b ath9k.ko
4034244 ath9k.ko
$ du -b ath9k-old.ko
4033788 ath9k-old.ko
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Check for IEEE80211_TX_CTL_NO_ACK instead of is_multicast_ether_addr
when determining whether to use lowest rate without retries.
Signed-off-by: Gábor Stefanik <netrolller.3d@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
net/mac80211/tx.c: In function ‘ieee80211_tx_h_select_key’:
net/mac80211/tx.c:448: warning: ‘key’ may be used uninitialized in this function
drivers/net/wireless/ath/ath9k/rc.c: In function ‘ath_rc_rate_getidx’:
drivers/net/wireless/ath/ath9k/rc.c:815: warning: ‘nextindex’ may be used uninitialized in this function
drivers/net/wireless/hostap/hostap_plx.c: In function ‘prism2_plx_probe’:
drivers/net/wireless/hostap/hostap_plx.c:438: warning: ‘cor_index’ may be used uninitialized in this function
drivers/net/wireless/hostap/hostap_plx.c:438: warning: ‘cor_offset’ may be used uninitialized in this function
Signed-off-by: John W. Linville <linville@tuxdriver.com>
