This reverts commit a2064b7a4a.
when CONFIG_IWLAGN=n:
drivers/net/wireless/iwlwifi/iwl-rx.c:254: error: 'struct iwl_priv' has no member named '_agn'
drivers/net/wireless/iwlwifi/iwl-rx.c:303: error: 'struct iwl_priv' has no member named '_agn'
drivers/net/wireless/iwlwifi/iwl-rx.c:304: error: 'struct iwl_priv' has no member named '_agn'
drivers/net/wireless/iwlwifi/iwl-rx.c:305: error: 'struct iwl_priv' has no member named '_agn'
drivers/net/wireless/iwlwifi/iwl-rx.c:306: error: 'struct iwl_priv' has no member named '_agn'
and many more.
Conflicts:
drivers/net/wireless/iwlwifi/iwl-agn-debugfs.c
drivers/net/wireless/iwlwifi/iwl-debugfs.c
drivers/net/wireless/iwlwifi/iwl-dev.h
drivers/net/wireless/iwlwifi/iwl-rx.c
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
It may be desirable in some systems to have
insight into the driver via debugfs, but not
affect its operation via the debug logging
code that is inserted everywhere when DEBUG
is configured.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
agn and 3945 has different statistics_notif data structure; since 3945
has it statistics_notif data structure inside the _3945 portion of
iwl_priv, it make sense to move the agn statistics_notif into _agn portion.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Add plcp error checking for 3945. After threshold of plcp
is reached , it resets the radio
Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Multiple error condition require fw/rf reset, driver should check all
the possible errors as long as the error checking functions for the
devices are available.
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
We go to great lengths to calculate this value
that is never used by mac80211. Additionally,
it is now deprecated by mac80211 and is causing
driver compilation to give warnings.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Move more functions only used by agn driver from iwlcore to iwlagn.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Identify the rx functions only used by agn driver and move those from
iwlcore to iwlagn.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Identify the tx functions only used by agn driver and move those from
iwlcore to iwlagn.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
iwl_good_ack_health() check for expected and actual ack count which only
apply to aggregation mode. Move the function to iwlagn module.
Reported-by: Chantry Xavier <chantry.xavier@gmail.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
This reverts commit 76232ebf89.
iwl_good_ack_health only applies to aggregation and thus only to iwlagn. We
can thus move the function to iwlagn instead of modifying compile flags.
This is done in following patch.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
drivers/net/wireless/iwlwifi/iwl-rx.c: In function 'iwl_good_ack_health':
drivers/net/wireless/iwlwifi/iwl-rx.c:647: error: 'struct iwl_priv' has no member named '_agn'
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Split the connectivity check and recovery routine into separated
functions based on the types
1. iwl_good_ack_health() - check for ack count
2. iwl_good_plcp_health() - check for plcp error
Based on the type of errors being detected, different recovery methods
will be used to bring the system back to normal operational state.
Because different NIC has different HW and uCode, the behavior is also
different; these functions thus now form part of the ops infrastructure,
so we can have more control on how to monitor and recover from error condition
case per device.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Monitors the tx statistics to detect the drop in throughput.
When the throughput drops, the ratio of the actual_ack_count and the
expected_ack_count also drops. At the same time, the aggregated
ba_timeout (the number of ba timeout retries) also rises. If the
actual_ack_count/expected_ack_count ratio is 0 and the number of ba
timeout retries rises to BA_TIMEOUT_MAX, no tx packets can be delivered.
Reloading the uCode and bring the system back to normal operational
state.
Signed-off-by: Trieu 'Andrew' Nguyen <trieux.t.nguyen@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Move the plcp error checking into stand alone function and pointed by ops
to accommodate devices not needing this recovery.
Signed-off-by: Trieu 'Andrew' Nguyen <trieux.t.nguyen@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Updating the variables last_rx_rssi, last_tsf
and last_beacon_time needs a lot of code but
they are not actually used in iwlagn (only in
3945) so we can move them to the 3945 specific
data.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
This reverts commit 1db5950f1d.
The goal of "iwlwifi: Monitor and recover the aggregation TX flow failure"
is to first detect when data transmission stalls and then to recover from
this situation with a reset of the radio or the firmware, depending on how
bad the transmission failures are.
Unfortunately we have found that this change causes excessive resets with
its current detection algorithm. It also performs its recovery action when
none is really needed, like when we are not associated.
Revert this change until the issues have been addressed.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Previous patch "use paged Rx" broke AMSDU Rx functionality. If an AP
sends out A-MSDU packets the station will crash. Fix it by linearizing
skbuff for AMSDU packet before handing it to mac80211 since mac80211
doesn't support paged skbuff.
This fixes http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=2155
Reported-by: Norbert Preining <preining@logic.at>
Signed-off-by: Shanyu Zhao <shanyu.zhao@intel.com>
Acked-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This change monitors the tx statistics to detect the drop in throughput.
When the throughput drops, the ratio of the actual_ack_count and the expected_
ack_count also drops. At the same time, the aggregated ba_timeout (the number
of ba timeout retries) also rises. If the actual_ack_count/expected_ack_count
ratio is 0 and the number of ba timeout retries rises to 16, no tx packets
(tcp, udp, or ping - icmp) can be delivered. The driver recovers from this
situation by reseting the uCode firmware. If the actual_ack_count/expected_
ack_count ratio drops below 50% (but not 0) and the aggregated ba_timeout
retries just exceed 5 (but not 16), then the driver can reset the radio to
bring the throughput up.
Signed-off-by: Trieu 'Andrew' Nguyen <trieux.t.nguyen@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Change pci_alloc_consistent() to dma_alloc_coherent() so we can use
GFP_KERNEL flag.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Provide the function to perform different type of uCode reset/reload operation.
When uCode detect error and can not fix itself, this iwl_force_reset()
function allow driver to perform the necessary reset/reload functions and help
to bring uCode back to normal operation state.
Currently only 2 type of force reset are available:
- reset radio
- reload firmware
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
In iwlagn the support for spectrum measurement command has been
disabled since v2.6.29 without any requests for it. In addition to this
when this command is indeed enabled it has been found to trigger firmware
SYSASSERT on at least 4965 and 5100 hardware (see
http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=1952 ). Since then
this code has been bitrotting and cannot just be enabled without porting.
Remove support for spectrum measurement command from iwlagn. It can be
added back if there is a future need and the firmware problem it triggers
has been fixed. Support for the spectrim measurement notification remains
as it has been enabled all the time.
In addition to this remove the 3945 spectrum measurement command Kconfig
option and make this command always supported. The code added by this
enabling is minimal and only run when user triggers a spectrum measurement
request via sysfs.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
We have seen the throughput dropped due to external noisy environment
and the radio is out of tune. There are lot of plcp errors indicating
this condition. Eventually the station can get de-authenticated by the
Access Point. By resetting and tuning the radio, the plcp errors are
reduced or eliminated and the throughput starts to rise.
To prevent unexpected behavior such as drop in throughput or deauthentication,
- The change provides the driver feature to monitor and tune the radio base on
the statistics notification from the uCode.
- It also allows the setting of the plcp error rate threshold via
the plcp_delta under debugfs interface.
Signed-off-by: Trieu 'Andrew' Nguyen <trieux.t.nguyen@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add support to configure missed beacon threshold, by default, if receive
"missed beacon" notification from uCode and has more than 5 consecutive
beacon missed, then perform sensitivity calibration; with this change,
allow user to adjust the missed beacon threshold from debugfs in case
more sensitivity calibration required for better performance in noisy
environment
The default value (=5) should be good enough for the normal condition,
but for very noisy environment, more sensitivity calibration could help
improve the throughput, so by setting the missed beacon threshold to
lower number, user might experience better performance result.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For interrupt coalescing timer, the CSR_INT_COALESCING is an 8 bit
register in 32-usec unit, the range can go from 0x00 - 0xFF. set the
range and default timeout value for both calibration mode and operation mode.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
To help debug uCode related problem, adding "delta" and "max"
information in debugfs statistics counters display.
Those information show the delta between two statistics report from
uCode, user can monitor the counters for any "un-normal" behavior.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Jay Sternberg<jay.e.sternberg@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When receive reply statistics command with "clear" mask, just reset the
accumulated statistics counters, but not the current statistics counters,
so the accumulated statistics counter can provide the correct
information.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This removes the remaining users of the rx status
'qual' field and the field itself.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In iwlwifi, priv->alloc_rxb_page is used to keep track of the Rx
pages allocated by the driver. This cleans up the page free routines
by introducing __iwl_free_pages/iwl_free_pages so that the accounting
is more accurate and less error prone. This also fixes two instances where
the counter was not updated.
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
CSR_INT_COALESCING previously had only one, but now has two single-byte fields.
With only one single-byte field (lowest order byte) it was okay to write via
iwl_write32(), but now with two, an iwl_write32() to the lower order field
clobbers the other field (odd-address CSR_INT_PERIODIC_REG, offset 0x5), and an
iwl_write32() to CSR_INT_PERIODIC_REG could clobber the lowest byte of the
next-higher register (CSR_INT, offset 0x8).
Fortunately, no bad side effects have been produced by the iwl_write32()
usage, due to order of execution (low order byte was always written before
higher order byte), and the fact that writing "0" to the low byte of the
next higher register has no effect (only action is when writing "1"s).
Nonetheless, this cleans up the accesses so no bad side effects might occur
in the future, if execution order changes, or more bit fields get added to
CSR_INT_COALESCING.
Add some comments regarding periodic interrupt usage.
Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Using the new mac80211 functionality, this makes
iwlwifi handle unicast PS buffering correctly.
The device works like this:
* when a station goes to sleep, the microcode notices
this and marks the station as asleep
* when the station is marked asleep, the microcode
refuses to transmit to the station and rejects all
frames queued to it with the failure status code
TX_STATUS_FAIL_DEST_PS (a previous patch handled
this correctly)
* when we need to send frames to the station _although_
it is asleep, we need to tell the ucode how many,
and this is asynchronous with sending so we cannot
just send the frames, we need to wait for all other
frames to be flushed, and then update the counter
before sending out the poll response frames. This
is handled partially in the driver and partially in
mac80211.
In order to do all this correctly, we need to
* keep track of how many frames are pending for each
associated client station (avoid doing it for other
stations to avoid the atomic ops)
* tell mac80211 that we driver-block the PS status
while there are still frames pending on the queues,
and once they are all rejected (due to the dest sta
being in PS) unblock mac80211
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When issue REPLY_STATISTICS_CMD to uCode, two possible flag
can be set in the configuration flags
bit 0: Clear statistics
0: Do not clear Statistics counters
1: Clear to zero Statistics counters
Allow "clear" parameter to be set from the caller.
Add debugfs file to clear the statistics counters to help monitor and
debug the uCode behavior.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add txq_id info to "Tx queue requesting wakeup" debug message
Add "Rx queue requesting wakeup" debug message
Move clear of CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ to be after nearby
iwl_write_prph(), since iwl_write_prph() sets it and clears it. Almost
removed it entirely, but just making sure in case someone removes the
iwl_write_prph()! Also remove unneeded priv->lock usage; this is now
handled by priv->reg_lock within iwl_clear_bit().
Join a couple of lines that had unneeded line returns.
Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Allocate 128 bytes linear buffer for rx skb. The first 64 bytes is
reserved for mac80211 usage (for radiotap header expansion, etc).
The frame header starts from the second 64 bytes.
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In the paged rx patch (4854fde2), I introduced a bug that could possibly
touch an already freed page. It is fixed by avoiding the access in this
patch. I've also added some comments so that other people touching the
code won't make the same mistake. In the future, if we cannot avoid
access the page after being handled to the upper layer, we can use
get_page/put_page to handle it. For now, it's just not necessary.
It also fixed a debug message print bug reported by Stanislaw Gruszka
<sgruszka@redhat.com>.
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Detach led background task from statistic notification routine. if led
blinking is required; the blink rate is based on the traffic condition.
It do not relate to statistics notification. In addition to that, there is
not a requirement for statistics notification has to occur all the time.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This switches the iwlwifi driver to use paged skb from linear skb for Rx
buffer. So that it relieves some Rx buffer allocation pressure for the
memory subsystem. Currently iwlwifi (4K for 3945) requests 8K bytes for
Rx buffer. Due to the trailing skb_shared_info in the skb->data,
alloc_skb() will do the next order allocation, which is 16K bytes. This
is suboptimal and more likely to fail when the system is under memory
usage pressure. Switching to paged Rx skb lets us allocate the RXB
directly by alloc_pages(), so that only order 1 allocation is required.
It also adjusts the area spin_lock (with IRQ disabled) protected in the
tasklet because tasklet guarentees to run only on one CPU and the new
unprotected code can be preempted by the IRQ handler. This saves us from
spawning another workqueue to make skb_linearize/__pskb_pull_tail happy
(which cannot be called in hard irq context).
Finally, mac80211 doesn't support paged Rx yet. So we linearize the skb
for all the management frames and software decryption or defragmentation
required data frames before handed to mac80211. For all the other frames,
we __pskb_pull_tail 64 bytes in the linear area of the skb for mac80211
to handle them properly.
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Adding accumulative statistics counters in iwlwifi driver.
Statistics counters are reported by uCode every beacon interval; but can
be reset by uCode when needed. The accumulative statistics counters is
maintained by driver to keep track of the history of all the counters.
Update the ucode stats files in debugfs to display both latest and
accumulative counters.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Fixes following on big endian systems:
CC [M] drivers/net/wireless/iwlwifi/iwl-rx.o
drivers/net/wireless/iwlwifi/iwl-rx.c: In function ‘iwl_rx_reply_rx’:
drivers/net/wireless/iwlwifi/iwl-rx.c:1029: warning: integer overflow in
expression
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Reported-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Replenishment of receive buffers is done in the tasklet handling
received frames as well as in a workqueue. When we are in the tasklet
we cannot sleep and thus attempt atomic skb allocations. It is generally
not a big problem if this fails since iwl_rx_allocate is always followed
by a call to iwl_rx_queue_restock which will queue the work to replenish
the buffers at a time when sleeping is allowed.
We thus add the __GFP_NOWARN to the skb allocation in iwl_rx_allocate to
reduce the noise if such an allocation fails while we still have enough
buffers. We do maintain the warning and the error message when we are low
on buffers to communicate to the user that there is a potential problem with
memory availability on system
This addresses issue reported upstream in thread "iwlagn: order 2 page
allocation failures" in
http://thread.gmane.org/gmane.linux.kernel.wireless.general/39187
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
RX handling maintains a few lists that keep track of the RX buffers.
Buffers move from one list to the other as they are used, replenished, and
again made available for usage. In one such instance, when a buffer is used
it enters the "rx_used" list. When buffers are replenished an skb is
attached to the buffer and it is moved to the "rx_free" list. The problem
here is that the buffer is first removed from the "rx_used" list _before_ the
skb is allocated. Thus, if the skb allocation fails this buffer remains
removed from the "rx_used" list and is thus lost for future usage.
Fix this by first allocating the skb before trying to attach it to a list.
We add an additional check to not do this unnecessarily.
Reported-by: Rick Farrington <rickdic@hotmail.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
John W. Linville