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Alexei Starovoitov b625030c90 Merge branch 'bpf: add percpu stats for bpf_map'
Anton Protopopov says:

====================
This series adds a mechanism for maps to populate per-cpu counters on
insertions/deletions. The sum of these counters can be accessed by a new kfunc
from map iterator and tracing programs.

The following patches are present in the series:

  * Patch 1 adds a generic per-cpu counter to struct bpf_map
  * Patch 2 adds a new kfunc to access the sum of per-cpu counters
  * Patch 3 utilizes this mechanism for hash-based maps
  * Patch 4 extends the preloaded map iterator to dump the sum
  * Patch 5 adds a self-test for the change

The reason for adding this functionality in our case (Cilium) is to get signals
about how full some heavy-used maps are and what the actual dynamic profile of
map capacity is. In the case of LRU maps this is impossible to get this
information anyhow else. The original presentation can be found here [1].

  [1] https://lpc.events/event/16/contributions/1368/

v4 -> v5:
* don't pass useless empty opts when creating a link, pass NULL (Hou)
* add a debug message (Hou)
* make code more readable (Alexei)
* remove the selftest which only checked that elem_count != NULL

v3 -> v4:
* fix selftests:
  * added test code for batch map operations
  * added a test for BPF_MAP_TYPE_HASH_OF_MAPS (Hou)
  * added tests for BPF_MAP_TYPE_LRU* with BPF_F_NO_COMMON_LRU (Hou)
  * map_info was called multiple times unnecessarily (Hou)
  * small fixes + some memory leaks (Hou)
* fixed wrong error path for freeing a non-prealloc map (Hou)
* fixed counters for batch delete operations (Hou)

v2 -> v3:
- split commits to better represent update logic (Alexei)
- remove filter from kfunc to allow all tracing programs (Alexei)
- extend selftests (Alexei)

v1 -> v2:
- make the counters generic part of struct bpf_map (Alexei)
- don't use map_info and /proc/self/fdinfo in favor of a kfunc (Alexei)
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-06 12:42:31 -07:00
arch Networking changes for 6.5. 2023-06-28 16:43:10 -07:00
block - Yosry Ahmed brought back some cgroup v1 stats in OOM logs. 2023-06-28 10:28:11 -07:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24 15:50:13 -07:00
Documentation bpf, docs: Fix definition of BPF_NEG operation 2023-06-29 15:58:50 +02:00
drivers bpf: Replace deprecated -target with --target= for Clang 2023-06-29 15:46:17 +02:00
fs Networking changes for 6.5. 2023-06-28 16:43:10 -07:00
include bpf: add percpu stats for bpf_map elements insertions/deletions 2023-07-06 12:42:25 -07:00
init - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in 2023-06-28 10:59:38 -07:00
io_uring Networking changes for 6.5. 2023-06-28 16:43:10 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel bpf: make preloaded map iterators to display map elements count 2023-07-06 12:42:25 -07:00
lib lib/test_bpf: Call page_address() on page acquired with GFP_KERNEL flag 2023-06-29 15:32:25 +02:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm Networking changes for 6.5. 2023-06-28 16:43:10 -07:00
net selftests/bpf: Add test to exercise typedef walking 2023-06-30 10:36:08 +02:00
rust rust: error: impl Debug for Error with errname() integration 2023-06-13 01:24:42 +02:00
samples bpf: Replace deprecated -target with --target= for Clang 2023-06-29 15:46:17 +02:00
scripts Networking changes for 6.5. 2023-06-28 16:43:10 -07:00
security v6.5-rc1-sysctl-next 2023-06-28 16:05:21 -07:00
sound regulator: Updates for v6.5 2023-06-28 13:32:47 -07:00
tools selftests/bpf: test map percpu stats 2023-07-06 12:42:25 -07:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt - Yosry Ahmed brought back some cgroup v1 stats in OOM logs. 2023-06-28 10:28:11 -07:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap NFSD 6.5 Release Notes 2023-06-26 10:48:57 -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 - Address -Wmissing-prototype warnings 2023-06-26 16:43:54 -07:00
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 Networking changes for 6.5. 2023-06-28 16:43:10 -07:00
Makefile hardening updates for v6.5-rc1 2023-06-27 21:24:18 -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.