74d47d75be
I think we can get rid of the spinlock protecting the kthread from being interrupted by a wakeup in certain parts. Even with the current implementation of the kthread the only lost wakeup scenario could happen if the wakeup occurs between the kfifo_len check and setting the state to TASK_INTERRUPTIBLE. In the changed version we could lose a wakeup if it occurs between processing the fifo content and setting the state to TASK_INTERRUPTIBLE. This scenario is covered by an additional check for available events in the fifo and setting the state to TASK_RUNNING in this case. In addition the changed version flushes the kfifo before ending when the kthread is stopped. With this patch we gain: - Get rid of the spinlock - Simplify code - Don't grep / release the mutex for each individual event but just once for the complete fifo content. This reduces overhead if a driver e.g. triggers processing after writing the content of a hw fifo to the kfifo. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> |
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| Documentation | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.