No description
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Guoqing Jiang d715ff8acb RDMA/rtrs-srv: Don't guard the whole __alloc_srv with srv_mutex
The purpose of srv_mutex is to protect srv_list as in put_srv, so no need
to hold it when allocate memory for srv since it could be time consuming.

Otherwise if one machine has limited memory, rsrv_close_work could be
blocked for a longer time due to the mutex is held by get_or_create_srv
since it can't get memory in time.

  INFO: task kworker/1:1:27478 blocked for more than 120 seconds.
        Tainted: G           O    4.14.171-1-storage #4.14.171-1.3~deb9
  "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  kworker/1:1     D    0 27478      2 0x80000000
  Workqueue: rtrs_server_wq rtrs_srv_close_work [rtrs_server]
  Call Trace:
   ? __schedule+0x38c/0x7e0
   schedule+0x32/0x80
   schedule_preempt_disabled+0xa/0x10
   __mutex_lock.isra.2+0x25e/0x4d0
   ? put_srv+0x44/0x100 [rtrs_server]
   put_srv+0x44/0x100 [rtrs_server]
   rtrs_srv_close_work+0x16c/0x280 [rtrs_server]
   process_one_work+0x1c5/0x3c0
   worker_thread+0x47/0x3e0
   kthread+0xfc/0x130
   ? trace_event_raw_event_workqueue_execute_start+0xa0/0xa0
   ? kthread_create_on_node+0x70/0x70
   ret_from_fork+0x1f/0x30

Let's move all the logics from __find_srv_and_get and __alloc_srv to
get_or_create_srv, and remove the two functions. Then it should be safe
for multiple processes to access the same srv since it is protected with
srv_mutex.

And since we don't want to allocate chunks with srv_mutex held, let's
check the srv->refcount after get srv because the chunks could not be
allocated yet.

Fixes: 9cb8374804 ("RDMA/rtrs: server: main functionality")
Link: https://lore.kernel.org/r/20201023074353.21946-6-jinpu.wang@cloud.ionos.com
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
History 2020-10-28 13:17:40 -03:00
arch treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
block block-5.10-2020-10-24 2020-10-24 12:46:42 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto drivers-5.10-2020-10-12 2020-10-13 13:04:41 -07:00
Documentation xen: branch for v5.10-rc1c 2020-10-25 10:55:35 -07:00
drivers RDMA/rtrs-srv: Don't guard the whole __alloc_srv with srv_mutex 2020-10-28 13:17:40 -03:00
fs treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
include IB/verbs: avoid nested container_of() 2020-10-28 10:06:51 -03:00
init linux-kselftest-kunit-5.10-rc1 2020-10-18 14:45:59 -07:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
lib random32: make prandom_u32() less predictable 2020-10-25 10:40:08 -07:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm Refactored code for 5.10: 2020-10-23 11:33:41 -07:00
net mm: remove kzfree() compatibility definition 2020-10-25 11:39:02 -07:00
samples bpf, libbpf: Guard bpf inline asm from bpf_tail_call_static 2020-10-22 01:46:52 +02:00
scripts treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
security SafeSetID changes for v5.10 2020-10-25 10:45:26 -07:00
sound ARM: SoC platform updates 2020-10-24 10:33:08 -07:00
tools treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt kvm: x86/mmu: Support dirty logging for the TDP MMU 2020-10-23 03:42:13 -04:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap MAINTAINERS: jarkko.sakkinen@linux.intel.com -> jarkko@kernel.org 2020-10-16 11:11:19 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS networking changes for the 5.10 merge window 2020-10-15 18:42:13 -07:00
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 ARM: Devicetree updates 2020-10-24 10:44:18 -07:00
Makefile Linux 5.10-rc1 2020-10-25 15:14:11 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.