buf::Block_hint Class Reference

#include <buf0block_hint.h>

Public Member Functions
void	store (buf_block_t *block)
	Stores the pointer to the block, which is currently buffer-fixed. More...
void	clear ()
	Clears currently stored pointer. More...
template<typename F >
auto	run_with_hint (F &&f)
	Executes given function with the block pointer which was previously stored or with nullptr if the pointer is no longer valid, was cleared or not stored. More...

Private Member Functions
void	buffer_fix_block_if_still_valid ()
	A helper function which checks if m_block is not a dangling pointer and still points to block with page with m_page_id and if so, buffer-fixes it, otherwise clear()s it. More...

Static Private Member Functions
static void	buffer_unfix_block_if_needed (buf_block_t *block)
	A helper function which decrements block->buf_fix_count if it's non-null. More...

Private Attributes
buf_block_t *	m_block {nullptr}
	The block pointer stored by store(). More...
page_id_t	m_page_id {0, 0}
	If m_block is non-null, the m_block->page.id at time it was stored. More...

Member Function Documentation

buffer_fix_block_if_still_valid()

void buf::Block_hint::buffer_fix_block_if_still_valid ( )

private

A helper function which checks if m_block is not a dangling pointer and still points to block with page with m_page_id and if so, buffer-fixes it, otherwise clear()s it.

buffer_unfix_block_if_needed()

void buf::Block_hint::buffer_unfix_block_if_needed ( buf_block_t *  block )

staticprivate

A helper function which decrements block->buf_fix_count if it's non-null.

Parameters

[in]

block

A pointer to a block or nullptr

clear()

void buf::Block_hint::clear

(

)

Clears currently stored pointer.

run_with_hint()

template<typename F >

auto buf::Block_hint::run_with_hint ( F &&  f )

inline

Executes given function with the block pointer which was previously stored or with nullptr if the pointer is no longer valid, was cleared or not stored.

Parameters

[in]

f

The function to be executed. It will be passed the pointer. If you wish to use the block pointer subsequently, you need to ensure you buffer-fix it before returning from f.

Returns

the return value of f

store()

void buf::Block_hint::store

(

buf_block_t *

block

)

Stores the pointer to the block, which is currently buffer-fixed.

Parameters

[in]

block

a pointer to a buffer-fixed block to be stored

Member Data Documentation

m_block

buf_block_t* buf::Block_hint::m_block {nullptr}

private

The block pointer stored by store().

m_page_id

page_id_t buf::Block_hint::m_page_id {0, 0}

private

If m_block is non-null, the m_block->page.id at time it was stored.

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

• storage/innobase/include/buf0block_hint.h
• storage/innobase/buf/buf0block_hint.cc