[FS#111] [ath9k] Commit 207338c causes WiFi performance regression(160MBit -> 45MBit)

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Zhong Jianxin (azuwis) 

Attached to Project - LEDE Project
Summary - [ath9k] Commit 207338c causes WiFi performance regression(160MBit -> 45MBit)
Task Type - Bug Report
Category - Kernel
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Low
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - Tested with Mercury MW4530R(TP-Link TL-WDR4310 clone).

Use commit 98e4b50(r1001) or revert 207338c, WiFi performance goes back to normal.

Git bisect log:

# bad: [4eb376586c5785025af07d439f58cb31337bb6b6] kernel: bgmac: use upstream accepted patches
# good: [7bdc21de7241f779146be2dd7c77bb3a8067a672] image.mk: fix append-dtb race when multiple devices use the same .dts
git bisect start 'master' '7bdc21d' '--'
# bad: [ea6a3be62eb980313f009acdc6f4dafddf48a3b7] kernel: silence a false positive uninitialized variable warning
git bisect bad ea6a3be62eb980313f009acdc6f4dafddf48a3b7
# bad: [18f368fa35269aba4ad444d3a4bae06d4608a2c8] linux: Get rid of 000-keep_initrafs_the_default.patch
git bisect bad 18f368fa35269aba4ad444d3a4bae06d4608a2c8
# bad: [eceb6b924aea73223ea0b64c6ccf8c5d87a8138d] x86: remove obsolete reference to $(PROFILE)
git bisect bad eceb6b924aea73223ea0b64c6ccf8c5d87a8138d
# bad: [d963ddf0424a551e5fadd561c934bfdb5d198764] ar71xx: add support for gl-ar300m
git bisect bad d963ddf0424a551e5fadd561c934bfdb5d198764
# bad: [56f686b7107b17341e6357e31435237e6fb1bb0c] samba36: disable local browse master by default
git bisect bad 56f686b7107b17341e6357e31435237e6fb1bb0c
# bad: [efdd3bf5fbab94b3f84e8a285e83ef36e39b3e8b] scripts/getver.sh: fix older git versions from printing stuff to stdout
git bisect bad efdd3bf5fbab94b3f84e8a285e83ef36e39b3e8b
# bad: [207338c78edbd4d52767f1b20b9a95bdb32c29dd] ath9k: implement temperature compensation support for AR93xx and newer
git bisect bad 207338c78edbd4d52767f1b20b9a95bdb32c29dd
# good: [98e4b504b45c5d6e68a48fc815e3d2a5d0d2ba13] ath9k: use external reset on AR91xx and QCA955x to improve stability
git bisect good 98e4b504b45c5d6e68a48fc815e3d2a5d0d2ba13
# first bad commit: [207338c78edbd4d52767f1b20b9a95bdb32c29dd] ath9k: implement temperature compensation support for AR93xx and newer


More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=111