forked from Minki/linux
mainlining shenanigans
5d18ee67d4
Currently the driver doesn't support completion vectors. These are used to indicate which sets of CQs should be grouped together into the same vector. A vector is a CQ processing thread that runs on a specific CPU. If an application has several CQs bound to different completion vectors, and each completion vector runs on different CPUs, then the completion queue workload is balanced. This helps scale as more nodes are used. Implement CQ completion vector support using a global workqueue where a CQ entry is queued to the CPU corresponding to the CQ's completion vector. Since the workqueue is global, it's guaranteed to always be there when queueing CQ entries; Therefore, the RCU locking for cq->rdi->worker in the hot path is superfluous. Each completion vector is assigned to a different CPU. The number of completion vectors available is computed by taking the number of online, physical CPUs from the local NUMA node and subtracting the CPUs used for kernel receive queues and the general interrupt. Special use cases: * If there are no CPUs left for completion vectors, the same CPU for the general interrupt is used; Therefore, there would only be one completion vector available. * For multi-HFI systems, the number of completion vectors available for each device is the total number of completion vectors in the local NUMA node divided by the number of devices in the same NUMA node. If there's a division remainder, the first device to get initialized gets an extra completion vector. Upon a CQ creation, an invalid completion vector could be specified. Handle it as follows: * If the completion vector is less than 0, set it to 0. * Set the completion vector to the result of the passed completion vector moded with the number of device completion vectors available. Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
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. 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.