Adrian Chadd 470a7f4191 Migrate the TX path to a taskqueue for now, until a better way of ... implementing parallel TX and TX/RX completion can be done without simply abusing long-held locks. Right now, multiple concurrent ath_start() entries can result in frames being dequeued out of order. Well, they're dequeued in order fine, but if there's any preemption or race between CPUs between: * removing the frame from the ifnet, and * calling and runningath_tx_start(), until the frame is placed on a software or hardware TXQ Then although dequeueing the frame is in-order, queueing it to the hardware may be out of order. This is solved in a lot of other drivers by just holding a TX lock over a rather long period of time. This lets them continue to direct dispatch without races between dequeue and hardware queue. Note to observers: if_transmit() doesn't necessarily solve this. It removes the ifnet from the main path, but the same issue exists if there's some intermediary queue (eg a bufring, which as an aside also may pull in ifnet when you're using ALTQ.) So, until I can sit down and code up a much better way of doing parallel TX, I'm going to leave the TX path using a deferred taskqueue task. What I will likely head towards is doing a direct dispatch to hardware or software via if_transmit(), but it'll require some driver changes to allow queues to be made without using the really large ath_buf / ath_desc entries. TODO: * Look at how feasible it'll be to just do direct dispatch to ath_tx_start() from if_transmit(), avoiding doing _any_ intermediary serialisation into a global queue. This may break ALTQ for example, so I have to be delicate. * It's quite likely that I should break up ath_tx_start() so it deposits frames onto the software queues first, and then only fill in the 802.11 fields when it's being queued to the hardware. That will make the if_transmit() -> software queue path very quick and lightweight. * This has some very bad behaviour when using ACPI and Cx states. I'll do some subsequent analysis using KTR and schedgraph and file a follow-up PR or two. PR: kern/168649		2012-06-04 22:01:12 +00:00
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ath_dfs/null	Contribute some example code which demonstrates how to initialise the	2012-02-06 20:23:21 +00:00
ath_hal	Add the AR9280 workarounds for PCIe suspend/resume.	2012-05-26 01:36:25 +00:00
ath_rate	Add in some debugging code to check whether the current rate table has	2012-02-26 06:04:44 +00:00
ah_osdep.c	Stop using the hardware register value byte order swapping for now,	2012-04-19 03:26:21 +00:00
ah_osdep.h	Add placeholder methods for WMI command access (USB, perhaps SDIO later)	2012-04-25 01:42:22 +00:00
if_ath.c	Migrate the TX path to a taskqueue for now, until a better way of	2012-06-04 22:01:12 +00:00
if_ath_ahb.c	Begin merging in some of my 802.11n TX aggregation driver changes.	2011-11-08 02:12:11 +00:00
if_ath_beacon.c	Migrate most of the beacon handling functions out to if_ath_beacon.c.	2012-05-20 04:14:29 +00:00
if_ath_beacon.h	Migrate most of the beacon handling functions out to if_ath_beacon.c.	2012-05-20 04:14:29 +00:00
if_ath_debug.c	Migrate ath_debug and sc_debug from an int to a uint64_t / QUAD;	2012-05-15 23:39:37 +00:00
if_ath_debug.h	Migrate ath_debug and sc_debug from an int to a uint64_t / QUAD;	2012-05-15 23:39:37 +00:00
if_ath_keycache.c	Add a 'vap' to ath_keyset().	2011-11-08 19:25:52 +00:00
if_ath_keycache.h	Add a 'vap' to ath_keyset().	2011-11-08 19:25:52 +00:00
if_ath_led.c	Since the only thing with a mux is the AR5416 and later, and we're now	2011-12-26 07:48:29 +00:00
if_ath_led.h	Refactor out the software LED config code into a common function, called	2011-12-26 05:46:22 +00:00
if_ath_misc.h	Migrate the TX path to a taskqueue for now, until a better way of	2012-06-04 22:01:12 +00:00
if_ath_pci.c	Override some default values to work around various issues in the deep,	2012-04-15 00:04:23 +00:00
if_ath_rx.c	Migrate the TX path to a taskqueue for now, until a better way of	2012-06-04 22:01:12 +00:00
if_ath_rx.h	Migrate the bulk of the RX routines out from if_ath.c to if_ath_rx.[ch].	2012-05-20 02:05:10 +00:00
if_ath_sysctl.c	Migrate ath_debug and sc_debug from an int to a uint64_t / QUAD;	2012-05-15 23:39:37 +00:00
if_ath_sysctl.h	Break out most of the HAL related tweaks into a per-HAL instance,	2011-06-23 02:38:36 +00:00
if_ath_tdma.c	Migrate the TDMA management functions out of if_ath.c into if_ath_tdma.c.	2012-05-20 02:49:42 +00:00
if_ath_tdma.h	Migrate the TDMA management functions out of if_ath.c into if_ath_tdma.c.	2012-05-20 02:49:42 +00:00
if_ath_tsf.h	Migrate the bulk of the RX routines out from if_ath.c to if_ath_rx.[ch].	2012-05-20 02:05:10 +00:00
if_ath_tx.c	Avoid using hard-coded numbers here.	2012-05-26 01:35:11 +00:00
if_ath_tx.h	Delay sequence number allocation for A-MPDU until just before the frame	2012-03-20 04:50:25 +00:00
if_ath_tx_ht.c	As I thought, this is a bad idea. When forming aggregates, the RTS/CTS	2012-04-07 05:46:00 +00:00
if_ath_tx_ht.h	Introduce TX aggregation and software TX queue management	2011-11-08 22:43:13 +00:00
if_athdfs.h	Change the prototype so the radar enable can fail.	2012-01-28 21:44:42 +00:00
if_athioctl.h	Squirrel away SYNC interrupt debugging if it's enabled in the HAL.	2012-04-10 07:23:37 +00:00
if_athrate.h	Introduce TX aggregation and software TX queue management	2011-11-08 22:43:13 +00:00
if_athvar.h	Migrate the TX path to a taskqueue for now, until a better way of	2012-06-04 22:01:12 +00:00