mirror of https://gitee.com/openkylin/linux.git
4ca234a9cb
Anton Blanchard reported that his 4096 vcpu KVM guest took around 30 minutes to boot. He also analyzed it to the time taken to iterate while setting the cpu_core_mask. Further analysis shows that cpu_core_mask and cpu_cpu_mask for any CPU would be equal on Power. However updating cpu_core_mask took forever to update as its a per cpu cpumask variable. Instead cpu_cpu_mask was a per NODE /per DIE cpumask that was shared by all the respective CPUs. Also cpu_cpu_mask is needed from a scheduler perspective. However cpu_core_map is an exported symbol. Hence stop updating cpu_core_map and make it point to cpu_cpu_mask. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-3-srikar@linux.vnet.ibm.com |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| 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 | ||
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.