geopm::IOUring Class Reference

#include <IOUring.hpp>

Inheritance diagram for geopm::IOUring:

Public Member Functions
	IOUring ()=default
	Create and initialize an IO uring.
virtual	~IOUring ()=default
	Clean up the IO uring.
virtual void	submit ()=0
	Submit all prepared uring operations in a batch, and wait for all operations to return a result. Throws if there are errors interacting with the completion queue. Failures of batched operations are reported by ret from the operation's respective prep_... function call, and do not cause this function to throw.
virtual void	prep_read (std::shared_ptr< int > ret, int fd, void *buf, unsigned nbytes, off_t offset)=0
	Perform a pread in the next batch submission.
virtual void	prep_write (std::shared_ptr< int > ret, int fd, const void *buf, unsigned nbytes, off_t offset)=0
	Perform a pwrite in the next batch submission.

Static Public Member Functions
static std::unique_ptr< IOUring >	make_unique (unsigned entries)
	Create an object that supports an io_uring-like interface. The created object uses io_uring if supported, otherwise uses individual read/write operations.

Constructor & Destructor Documentation

IOUring()

geopm::IOUring::IOUring ( )

default

Create and initialize an IO uring.

~IOUring()

virtual geopm::IOUring::~IOUring ( )

virtualdefault

Clean up the IO uring.

Member Function Documentation

make_unique()

std::unique_ptr< IOUring > geopm::IOUring::make_unique ( unsigned  entries )

static

Create an object that supports an io_uring-like interface. The created object uses io_uring if supported, otherwise uses individual read/write operations.

Parameters

entries

Maximum number of queue operations to contain within a single batch submission.

prep_read()

virtual void geopm::IOUring::prep_read ( std::shared_ptr< int >  ret, int  fd, void *  buf, unsigned  nbytes, off_t  offset  )

pure virtual

Perform a pread in the next batch submission.

Parameters

ret	Where to store the operation's return value, which will be a non-negative number of bytes read, or -errno on failure, after submit() returns.
fd	Which already-opened file to read.
buf	Where to store the read data.
nbytes	Number of bytes to read into buf.
offset	Offset within fd to start the pread. -1 uses the existing offset of fd, like in read().

Exceptions

if	the queue is already full.

Implemented in geopm::IOUringFallback, and geopm::IOUringImp.

prep_write()

virtual void geopm::IOUring::prep_write ( std::shared_ptr< int >  ret, int  fd, const void *  buf, unsigned  nbytes, off_t  offset  )

pure virtual

Perform a pwrite in the next batch submission.

Parameters

ret	Where to store the operation's return value, which will be a non-negative number of bytes written, or -errno on failure, after submit() returns.
fd	Which already-opened file to write.
buf	Which data to write to the file.
nbytes	Number of bytes to write from buf.
offset	Offset within fd to start the pwrite. -1 uses the existing offset of fd, like in write().

Exceptions

if	the queue is already full.

Implemented in geopm::IOUringFallback, and geopm::IOUringImp.

submit()

virtual void geopm::IOUring::submit ( )

pure virtual

Submit all prepared uring operations in a batch, and wait for all operations to return a result. Throws if there are errors interacting with the completion queue. Failures of batched operations are reported by ret from the operation's respective prep_... function call, and do not cause this function to throw.

Implemented in geopm::IOUringFallback, and geopm::IOUringImp.

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The documentation for this class was generated from the following files:

• IOUring.hpp
• IOUring.cpp