e611f8cd87
Deferred probe usually runs only on pinned kworkers, which might take longer time if a device contains multiple sub-devices. One such case is of sound card on mobile devices, where we have good number of mixers and controls per mixer. We observed boot up improvement - deferred probes take ~600ms when bound to little core kworker and ~200ms when deferred probe is queued on unbound wq. This is due to scheduler moving the worker running deferred probe work to big CPUs. Without this change, we see the worker is running on LITTLE CPU due to affinity. Since kworker runs deferred probe of several devices, the locality may not be important. Also, init thread executing driver initcalls, can potentially migrate as it has cpu affinity set to all cpus.In addition to this, async probes use unbounded workqueue. So, using unbounded wq for deferred probes looks to be similar to these w.r.t. scheduling behavior. Signed-off-by: Yogesh Lal <ylal@codeaurora.org> Link: https://lore.kernel.org/r/1616583698-6398-1-git-send-email-ylal@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| 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.