Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
492e0d0d6f
Grabbing the spinlock for every bucket even if it's empty, was causing
significant perfomance cost when traversing htab maps that have only a
few entries. This patch addresses the issue by checking first the
bucket_cnt, if the bucket has some entries then we go and grab the
spinlock and proceed with the batching.
Tested with a htab of size 50K and different value of populated entries.
Before:
Benchmark Time(ns) CPU(ns)
---------------------------------------------
BM_DumpHashMap/1 2759655 2752033
BM_DumpHashMap/10 2933722 2930825
BM_DumpHashMap/200 3171680 3170265
BM_DumpHashMap/500 3639607 3635511
BM_DumpHashMap/1000 4369008 4364981
BM_DumpHashMap/5k 11171919 11134028
BM_DumpHashMap/20k 69150080 69033496
BM_DumpHashMap/39k 190501036 190226162
After:
Benchmark Time(ns) CPU(ns)
---------------------------------------------
BM_DumpHashMap/1 202707 200109
BM_DumpHashMap/10 213441 210569
BM_DumpHashMap/200 478641 472350
BM_DumpHashMap/500 980061 967102
BM_DumpHashMap/1000 1863835 1839575
BM_DumpHashMap/5k 8961836 8902540
BM_DumpHashMap/20k 69761497 69322756
BM_DumpHashMap/39k 187437830 186551111
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| 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 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.