m_reg Kernel Service

Purpose

Registers expected mbuf usage.

Syntax

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/mbuf.h>

void m_reg ( mbp)
struct mbreq mbp;

Parameter

Item Description
mbp Defines the address of an mbreq structure that specifies expected mbuf usage.

Description

The m_reg kernel service lets users of mbuf services specify initial requirements. The m_reg kernel service also allows the buffer pool low-water and deallocation marks to be adjusted based on expected usage. Its use is recommended for better control of the buffer pool.

When the number of free mbuf structures falls below the low-water mark, the total mbuf pool is expanded. When the number of free mbuf structures rises above the deallocation mark, the total mbuf pool is contracted and resources are returned to the system.

Execution Environment

The m_reg kernel service can be called from the process environment only.

Return Values

The m_reg service has no return values.