mirror of https://github.com/torvalds/linux.git
593377036e
As of today, KVM notes a quiescent state only in guest entry, which is good as it avoids the guest being interrupted for current RCU operations. While the guest vcpu runs, it can be interrupted by a timer IRQ that will check for any RCU operations waiting for this CPU. In case there are any of such, it invokes rcu_core() in order to sched-out the current thread and note a quiescent state. This occasional schedule work will introduce tens of microsseconds of latency, which is really bad for vcpus running latency-sensitive applications, such as real-time workloads. So, note a quiescent state in guest exit, so the interrupted guests is able to deal with any pending RCU operations before being required to invoke rcu_core(), and thus avoid the overhead of related scheduler work. Signed-off-by: Leonardo Bras <leobras@redhat.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Sean Christopherson <seanjc@google.com> Message-ID: <20240511020557.1198200-1-leobras@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| 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 reStructuredText 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.