kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-26 19:14:18 +00:00
Code Issues Releases Packages Activity
No description
1,281,018 commits 117 branches 5,805 tags 5.9 GiB
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Gao Xiang d40c2865bd xfs: avoid redundant AGFL buffer invalidation 
Currently AGFL blocks can be filled from the following three sources:
 - allocbt free blocks, as in xfs_allocbt_free_block();
 - rmapbt free blocks, as in xfs_rmapbt_free_block();
 - refilled from freespace btrees, as in xfs_alloc_fix_freelist().

Originally, allocbt free blocks would be marked as stale only when they
put back in the general free space pool as Dave mentioned on IRC, "we
don't stale AGF metadata btree blocks when they are returned to the
AGFL .. but once they get put back in the general free space pool, we
have to make sure the buffers are marked stale as the next user of
those blocks might be user data...."

However, after commit ca250b1b3d ("xfs: invalidate allocbt blocks
moved to the free list") and commit edfd9dd549 ("xfs: move buffer
invalidation to xfs_btree_free_block"), even allocbt / bmapbt free
blocks will be invalidated immediately since they may fail to pass
V5 format validation on writeback even writeback to free space would be
safe.

IOWs, IMHO currently there is actually no difference of free blocks
between AGFL freespace pool and the general free space pool.  So let's
avoid extra redundant AGFL buffer invalidation, since otherwise we're
currently facing unnecessary xfs_log_force() due to xfs_trans_binval()
again on buffers already marked as stale before as below:

[  333.507469] Call Trace:
[  333.507862]  xfs_buf_find+0x371/0x6a0       <- xfs_buf_lock
[  333.508451]  xfs_buf_get_map+0x3f/0x230
[  333.509062]  xfs_trans_get_buf_map+0x11a/0x280
[  333.509751]  xfs_free_agfl_block+0xa1/0xd0
[  333.510403]  xfs_agfl_free_finish_item+0x16e/0x1d0
[  333.511157]  xfs_defer_finish_noroll+0x1ef/0x5c0
[  333.511871]  xfs_defer_finish+0xc/0xa0
[  333.512471]  xfs_itruncate_extents_flags+0x18a/0x5e0
[  333.513253]  xfs_inactive_truncate+0xb8/0x130
[  333.513930]  xfs_inactive+0x223/0x270

xfs_log_force() will take tens of milliseconds with AGF buffer locked.
It becomes an unnecessary long latency especially on our PMEM devices
with FSDAX enabled and fsops like xfs_reflink_find_shared() at the same
time are stuck due to the same AGF lock.  Removing the double
invalidation on the AGFL blocks does not make this issue go away, but
this patch fixes for our workloads in reality and it should also work
by the code analysis.

Note that I'm not sure I need to remove another redundant one in
xfs_alloc_ag_vextent_small() since it's unrelated to our workloads.
Also fstests are passed with this patch.

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
History 2024-07-01 09:32:29 +05:30
arch x86-32: fix cmpxchg8b_emu build error with clang 2024-06-30 09:21:29 -07:00
block block: unmap and free user mapped integrity via submitter 2024-06-12 11:00:50 -06:00
certs kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
crypto This push fixes a bug in the new ecc P521 code as well as a buggy 2024-05-20 08:47:54 -07:00
Documentation Kbuild fixes for v6.10 (third) 2024-06-30 10:00:01 -07:00
drivers ata fixes for 6.10-rc6 2024-06-30 14:32:24 -07:00
fs xfs: avoid redundant AGFL buffer invalidation 2024-07-01 09:32:29 +05:30
include ata fixes for 6.10-rc6 2024-06-30 14:32:24 -07:00
init gcc: disable '-Warray-bounds' for gcc-9 2024-06-15 10:43:04 -07:00
io_uring io_uring: signal SQPOLL task_work with TWA_SIGNAL_NO_IPI 2024-06-24 19:46:15 -06:00
ipc Mainly singleton patches, documented in their respective changelogs. 2024-05-19 14:02:03 -07:00
kernel TTY/Serial/Console fixes for 6.10-rc6 2024-06-30 08:57:43 -07:00
lib hardening fixes for v6.10-rc6 2024-06-28 16:11:02 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm/memory: don't require head page for do_set_pmd() 2024-06-24 20:52:11 -07:00
net NFS client bugfixes for Linux 6.10 2024-06-29 13:48:24 -07:00
rust rust: avoid unused import warning in rusttest 2024-06-11 23:33:28 +02:00
samples tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
scripts kbuild: scripts/gdb: bring the "abspath" back 2024-06-27 04:20:32 +09:00
security lsm/stable-6.10 PR 20240617 2024-06-17 18:35:12 -07:00
sound ASoC: Fixes for v6.10 2024-06-26 22:02:55 +02:00
tools Fix three recent minor turbostat regressions. 2024-06-28 09:04:33 -07:00
usr kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
virt KVM fixes for 6.10 2024-06-21 08:03:55 -04:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: create a list of all built DTB files 2024-02-19 18:20:39 +09:00
.mailmap bpf-for-netdev 2024-06-14 17:57:10 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Drop Gustavo Pimentel as PCI DWC Maintainer 2024-03-27 13:41:02 -05:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS IOMMU Fixes for Linux v6.10-rc5 2024-06-28 09:18:01 -07:00
Makefile Linux 6.10-rc6 2024-06-30 14:40:44 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

README 

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 reStructuredText 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.