Documentation/virt/paravirt_ops.rst
Source file repositories/reference/linux-study-clean/Documentation/virt/paravirt_ops.rst
File Facts
- System
- Linux kernel
- Corpus path
Documentation/virt/paravirt_ops.rst- Extension
.rst- Size
- 1544 bytes
- Lines
- 36
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: documentation
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
.. SPDX-License-Identifier: GPL-2.0
============
Paravirt_ops
============
Linux provides support for different hypervisor virtualization technologies.
Historically, different binary kernels would be required in order to support
different hypervisors; this restriction was removed with pv_ops.
Linux pv_ops is a virtualization API which enables support for different
hypervisors. It allows each hypervisor to override critical operations and
allows a single kernel binary to run on all supported execution environments
including native machine -- without any hypervisors.
pv_ops provides a set of function pointers which represent operations
corresponding to low-level critical instructions and high-level
functionalities in various areas. pv_ops allows for optimizations at run
time by enabling binary patching of the low-level critical operations
at boot time.
pv_ops operations are classified into three categories:
- simple indirect call
These operations correspond to high-level functionality where it is
known that the overhead of indirect call isn't very important.
- indirect call which allows optimization with binary patch
Usually these operations correspond to low-level critical instructions. They
are called frequently and are performance critical. The overhead is
very important.
- a set of macros for hand written assembly code
Hand written assembly codes (.S files) also need paravirtualization
because they include sensitive instructions or some code paths in
them are very performance critical.Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.