[tree-wide] finally take no_llseek out

no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

At -rc1 we'll need do a mechanical

[tree-wide] finally take no_llseek out

no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

At -rc1 we'll need do a mechanical removal of no_llseek -

git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done

would do it.

Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

mac80211: minstrel_ht: show sampling rates in debugfs

This makes it easier to see what rates are going to be tested next

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/

mac80211: minstrel_ht: show sampling rates in debugfs

This makes it easier to see what rates are going to be tested next

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210127055735.78599-5-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel_ht: use bitfields to encode rate indexes

Get rid of a lot of divisions and modulo operations
Reduces code size and improves performance

Signed-off-by: Felix Fietkau <nbd@nbd.name

mac80211: minstrel_ht: use bitfields to encode rate indexes

Get rid of a lot of divisions and modulo operations
Reduces code size and improves performance

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210127055735.78599-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: remove legacy minstrel rate control

Now that minstrel_ht supports legacy rates, it is no longer needed

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210115

mac80211: remove legacy minstrel rate control

Now that minstrel_ht supports legacy rates, it is no longer needed

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210115120242.89616-4-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel_ht: add support for OFDM rates on non-HT clients

The legacy minstrel code is essentially unmaintained and receives only very
little testing. In order to bring the significant algo

mac80211: minstrel_ht: add support for OFDM rates on non-HT clients

The legacy minstrel code is essentially unmaintained and receives only very
little testing. In order to bring the significant algorithm improvements from
minstrel_ht to legacy clients, this patch adds support for OFDM rates to
minstrel_ht and removes the fallback to the legacy codepath.
This also makes it work much better on hardware with rate selection constraints,
e.g. mt76.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210115120242.89616-3-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average

Reduces per-rate data structure size

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/2019

mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average

Reduces per-rate data structure size

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20191008171139.96476-3-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

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

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 #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

mac80211: minstrel_ht: add flag to indicate missing/inaccurate tx A-MPDU length

Some hardware (e.g. MediaTek MT7603) cannot report A-MPDU length in tx status
information. Add support for a flag to i

mac80211: minstrel_ht: add flag to indicate missing/inaccurate tx A-MPDU length

Some hardware (e.g. MediaTek MT7603) cannot report A-MPDU length in tx status
information. Add support for a flag to indicate that, to allow minstrel_ht
to use a fixed value in its internal calculation (which gives better results
than just defaulting to 1).

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: rc80211_minstrel: remove variance / stddev calculation

When there are few packets (e.g. for sampling attempts), the exponentially
weighted variance is usually vastly overestimated, making

mac80211: rc80211_minstrel: remove variance / stddev calculation

When there are few packets (e.g. for sampling attempts), the exponentially
weighted variance is usually vastly overestimated, making the resulting data
essentially useless. As far as I know, there has not been any practical use
for this, so let's not waste any cycles on it.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel: reduce minstrel_mcs_groups size

By storing a shift value for all duration values of a group, we can
reduce precision by a neglegible amount to make it fit into a u16 value.
This

mac80211: minstrel: reduce minstrel_mcs_groups size

By storing a shift value for all duration values of a group, we can
reduce precision by a neglegible amount to make it fit into a u16 value.
This improves cache footprint and reduces size:

Before:
text data bss dec hex filename
10024 116 0 10140 279c rc80211_minstrel_ht.o

After:
text data bss dec hex filename
9368 116 0 9484 250c rc80211_minstrel_ht.o

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel: merge with minstrel_ht, always enable VHT support

Legacy-only devices are not very common and the overhead of the extra
code for HT and VHT rates is not big enough to justify all

mac80211: minstrel: merge with minstrel_ht, always enable VHT support

Legacy-only devices are not very common and the overhead of the extra
code for HT and VHT rates is not big enough to justify all those extra
lines of code to make it optional.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel: remove unnecessary debugfs cleanup code

debugfs entries are cleaned up by debugfs_remove_recursive already.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes B

mac80211: minstrel: remove unnecessary debugfs cleanup code

debugfs entries are cleaned up by debugfs_remove_recursive already.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

net: Use octal not symbolic permissions

Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace nea

net: Use octal not symbolic permissions

Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace neatening around these conversions.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

mac80211: minstrel: store probability variance instead of standard deviation

This avoids the costly int_sqrt calls in the statistics update and moves
it to the debugfs code instead.
This also fixes

mac80211: minstrel: store probability variance instead of standard deviation

This avoids the costly int_sqrt calls in the statistics update and moves
it to the debugfs code instead.
This also fixes an overflow in the previous standard deviation
calculation.

Signed-off-by: Thomas Huehn <thomas.huehn@evernet-eg.de>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel: remove cur_prob from debugfs

This field is redundant, because it is simply last success divided by
last attempt count. Removing it from the rate stats struct saves about
1.2 KiB

mac80211: minstrel: remove cur_prob from debugfs

This field is redundant, because it is simply last success divided by
last attempt count. Removing it from the rate stats struct saves about
1.2 KiB per HT station.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel_ht: move supported bitrate mask out of group data

Improves dcache footprint by ensuring that fewer cache lines need to be
touched.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Sig

mac80211: minstrel_ht: move supported bitrate mask out of group data

Improves dcache footprint by ensuring that fewer cache lines need to be
touched.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel[_ht]: remove non-ascii debugfs characters

Replace the average symbol by "avg" to avoid being warned about the
non-ASCII symbol all the time, line up the columns properly.

(I chan

mac80211: minstrel[_ht]: remove non-ascii debugfs characters

Replace the average symbol by "avg" to avoid being warned about the
non-ASCII symbol all the time, line up the columns properly.

(I changed my mind - the warnings are getting annoying)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: add standard deviation to Minstrel stats

This patch adds the statistical descriptor "standard deviation"
to better describe the current properties of Minstrel and
Minstrel-HTs success prob

mac80211: add standard deviation to Minstrel stats

This patch adds the statistical descriptor "standard deviation"
to better describe the current properties of Minstrel and
Minstrel-HTs success probability distribution. The standard
deviation (SD) is calculated as exponential weighted moving
standard deviation (EWMSD) and its current value is added as
new column in all rc_stats (in debugfs).

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: add max lossless throughput per rate

This patch adds the new statistic "maximum possible lossless
throughput" to Minstrels and Minstrel-HTs rc_stats (in debugfs). This
enables comprehensiv

mac80211: add max lossless throughput per rate

This patch adds the new statistic "maximum possible lossless
throughput" to Minstrels and Minstrel-HTs rc_stats (in debugfs). This
enables comprehensive comparison between current per-rate throughput
and max. achievable per-rate throughput.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: restructure per-rate throughput calculation into function

This patch moves Minstrels and Minstrel-HTs per-rate throughput
calculation (EWMA(thr)) into a dedicated function to be called.
Th

mac80211: restructure per-rate throughput calculation into function

This patch moves Minstrels and Minstrel-HTs per-rate throughput
calculation (EWMA(thr)) into a dedicated function to be called.
Therefore the variable "unsigned int cur_tp" within struct
"minstrel_rate_stats" becomes obsolete. and is removed to free
up its space.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: improve Minstrel variable & function naming

This patch ensures a consistent usage of variable names for type
"minstrel_rate_stats" to be used as "mrs" and from type minstrel_rate
as "mr" a

mac80211: improve Minstrel variable & function naming

This patch ensures a consistent usage of variable names for type
"minstrel_rate_stats" to be used as "mrs" and from type minstrel_rate
as "mr" across both Minstrel & Minstrel-HT. In addition some
variable and function names got changed to more meaningful ones.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: add new Minstrel-HT statistic output via csv

This patch adds a new debugfs file "rc_stats_csv" to output
Minstrel-HTs statistics in a common csv format that is easy
to parse.

Signed-off-b

mac80211: add new Minstrel-HT statistic output via csv

This patch adds a new debugfs file "rc_stats_csv" to output
Minstrel-HTs statistics in a common csv format that is easy
to parse.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Stefan Venz <ikstream86@gmail.com>
Acked-by: Felix Fietkau <nbd@openwrt.org>
[remove printing current time of day]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: enhance readability of Minstrel-HTs rc_stats output

This patch restructures the rc_stats debugfs table of Minstrel-HT in
order to achieve better human readability. A new layout of the
stat

mac80211: enhance readability of Minstrel-HTs rc_stats output

This patch restructures the rc_stats debugfs table of Minstrel-HT in
order to achieve better human readability. A new layout of the
statistics and a new header is added. In addition to the old layout
there are two new columns of information added:
idx - representing the rate index of each rate in mac80211 which
can be used to set specific rates as fixed rate via debugfs
airtime - the tx-time in micro seconds that a 1200 Byte packet
takes to be transmitted over the air at the given rate

The old layout of rc_stats:

type rate tpt eprob *prob ret *ok(*cum) ok( cum)
HT20/LGI MCS0 5.6 100.0 100.0 1 0( 0) 1( 1)
HT20/LGI B MCS1 10.5 100.0 100.0 0 0( 0) 1( 1)
HT20/LGI A MCS2 14.8 100.0 100.0 0 0( 0) 1( 1)
...

is changed into this new layout:

best ________rate______ __statistics__ ________last_______ ______sum-of________
mode guard # rate [name idx airtime] [ ø(tp) ø(prob)] [prob.|retry|suc|att] [#success | #attempts]
HT20 LGI 1 MCS0 0 1480 0.0 0.0 0.0 1 0 0 0 0
HT20 LGI 1 B MCS1 1 740 10.5 100.0 100.0 0 0 0 1 1
HT20 LGI 1 A MCS2 2 496 14.8 100.0 100.0 0 0 0 1 1
...

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Stefan Venz <ikstream86@gmail.com>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel_ht: use group flags instead of index to display rates

When displaying a rate through debugfs minstrel_ht guesses its flags
comparing group indexes. Since 3ec373c421b6 ("mac80211:

mac80211: minstrel_ht: use group flags instead of index to display rates

When displaying a rate through debugfs minstrel_ht guesses its flags
comparing group indexes. Since 3ec373c421b6 ("mac80211: minstrel_ht:
include type (cck/ht) in rates flag"), the rate flags of interest are
present in the mcs_group-s, so use it.
While improving the code, this also fixes a smatch false positive
"error: testing array offset 'i' after use" in minstrel_ht_stats_dump.
This warning only triggers after 9208247d74bc ("mac80211: minstrel_ht:
add basic support for VHT rates <= 3SS@80MHz") with
CONFIG_MAC80211_RC_MINSTREL_VHT unset because then MINSTREL_VHT_GROUP_0
is above MINSTREL_GROUPS_NB and smatch only barks when the "testing
array offset" seems to prevent possible out of bonds accesses (which
does not happen here since i < ARRAY_SIZE(mi->groups)).

Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...

mac80211: minstrel_ht: add basic support for VHT rates <= 3SS@80MHz

When the new CONFIG_MAC80211_RC_MINSTREL_VHT is not set (default 'N'),
there is no behavioral change including in sampling and MCS

mac80211: minstrel_ht: add basic support for VHT rates <= 3SS@80MHz

When the new CONFIG_MAC80211_RC_MINSTREL_VHT is not set (default 'N'),
there is no behavioral change including in sampling and MCS_GROUP_RATES
remains 8.
Otherwise MCS_GROUP_RATES is 10, and a module parameter *vht_only*
(default 'true'), restricts the rates selection to VHT when VHT is
supported.

Regarding the debugfs stats buffer:
It is explicitly increased from 8k to 32k to fit every rates incl. when
both HT and VHT rates are enabled, as for the format, before:
type rate tpt eprob *prob ret *ok(*cum) ok( cum)
HT20/LGI ABCDP MCS0 0.0 0.0 0.0 1 0( 0) 0( 0)
after:
type rate tpt eprob *prob ret *ok(*cum) ok( cum)
HT20/LGI ABCDP MCS0 0.0 0.0 0.0 1 0( 0) 0( 0)
VHT40/LGI MCS5/2 0.0 0.0 0.0 0 0( 0) 0( 0)

Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

show more ...