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Weitao Wang 4d7da7e565 USB: HCD: Fix URB giveback issue in tasklet function
commit 26c6c2f8a9 upstream.

Usb core introduce the mechanism of giveback of URB in tasklet context to
reduce hardware interrupt handling time. On some test situation(such as
FIO with 4KB block size), when tasklet callback function called to
giveback URB, interrupt handler add URB node to the bh->head list also.
If check bh->head list again after finish all URB giveback of local_list,
then it may introduce a "dynamic balance" between giveback URB and add URB
to bh->head list. This tasklet callback function may not exit for a long
time, which will cause other tasklet function calls to be delayed. Some
real-time applications(such as KB and Mouse) will see noticeable lag.

In order to prevent the tasklet function from occupying the cpu for a long
time at a time, new URBS will not be added to the local_list even though
the bh->head list is not empty. But also need to ensure the left URB
giveback to be processed in time, so add a member high_prio for structure
giveback_urb_bh to prioritize tasklet and schelule this tasklet again if
bh->head list is not empty.

At the same time, we are able to prioritize tasklet through structure
member high_prio. So, replace the local high_prio_bh variable with this
structure member in usb_hcd_giveback_urb.

Fixes: 94dfd7edfd ("USB: HCD: support giveback of URB in tasklet context")
Cc: stable <stable@kernel.org>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Weitao Wang <WeitaoWang-oc@zhaoxin.com>
Link: https://lore.kernel.org/r/20220726074918.5114-1-WeitaoWang-oc@zhaoxin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:15:26 +02:00
arch MIPS: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK 2022-08-21 15:15:26 +02:00
block block: Fix handling of offline queues in blk_mq_alloc_request_hctx() 2022-06-22 14:13:17 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:13:17 +02:00
crypto crypto: memneq - move into lib/ 2022-06-22 14:13:18 +02:00
Documentation x86/speculation: Add RSB VM Exit protections 2022-08-11 13:06:47 +02:00
drivers USB: HCD: Fix URB giveback issue in tasklet function 2022-08-21 15:15:26 +02:00
fs fuse: limit nsec 2022-08-21 15:15:25 +02:00
include USB: HCD: Fix URB giveback issue in tasklet function 2022-08-21 15:15:26 +02:00
init Kconfig: Add option for asm goto w/ tied outputs to workaround clang-13 bug 2022-06-09 10:21:25 +02:00
ipc ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() 2022-06-09 10:21:17 +02:00
kernel watch_queue: Fix missing locking in add_watch_to_object() 2022-08-03 12:00:44 +02:00
lib ida: don't use BUG_ON() for debugging 2022-07-12 16:32:23 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm/mremap: hold the rmap lock in write mode when moving page table entries. 2022-08-21 15:15:21 +02:00
net bpf: Add PROG_TEST_RUN support for sk_lookup programs 2022-08-03 12:00:52 +02:00
samples x86: Prepare inline-asm for straight-line-speculation 2022-07-25 11:26:29 +02:00
scripts x86/retbleed: Add fine grained Kconfig knobs 2022-07-25 11:26:50 +02:00
security lockdown: Fix kexec lockdown bypass with ima policy 2022-07-29 17:19:06 +02:00
sound ALSA: hda/realtek: Add a quirk for HP OMEN 15 (8786) mute LED 2022-08-21 15:15:22 +02:00
tools x86/speculation: Add RSB VM Exit protections 2022-08-11 13:06:47 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:25:48 +01:00
virt KVM: Don't null dereference ops->destroy 2022-07-29 17:19:23 +02:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: generate Module.symvers only when vmlinux exists 2021-05-19 10:12:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: add Amir as xfs maintainer for 5.10.y 2022-07-02 16:39:22 +02:00
Makefile Makefile: link with -z noexecstack --no-warn-rwx-segments 2022-08-21 15:15:18 +02:00
README

Linux kernel
============

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Please read the Documentation/process/changes.rst file, as it contains the
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