880cb3cddd
Our current LPI allocator relies on a bitmap, each bit representing a chunk of 32 LPIs, meaning that each device gets allocated LPIs in multiple of 32. It served us well so far, but new use cases now require much more finer grain allocations, down the the individual LPI. Given the size of the IntID space (up to 32bit), it isn't practical to continue using a bitmap, so let's use a different data structure altogether. We switch to a list, where each element represent a contiguous range of LPIs. On allocation, we simply grab the first group big enough to satisfy the allocation, and substract what we need from it. If the group becomes empty, we just remove it. On freeing interrupts, we insert a new group of interrupt in the list, sort it and fuse the adjacent groups. This makes freeing interrupt much more expensive than allocating them (an unusual behaviour), but that's fine as long as we consider that freeing interrupts is an extremely rare event. We still allocate interrupts in blocks of 32 for the time being, but subsequent patches will relax this. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| 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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.