ddi_intr_hilevel(9F) Kernel Functions for Drivers ddi_intr_hilevel(9F)NAMEddi_intr_hilevel - indicate interrupt handler type
SYNOPSIS
#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_intr_hilevel(dev_info_t *dip, uint_t inumber);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). This interface is obsolete. Use the
new interrupt interfaces referenced in Intro(9F). Refer to Writing
Device Drivers for more information.
PARAMETERS
dip Pointer to dev_info structure.
inumber Interrupt number.
DESCRIPTION
The ddi_intr_hilevel() function returns non-zero if the specified
interrupt is a "high level" interrupt.
High level interrupts must be handled without using system services
that manipulate thread or process states, because these interrupts are
not blocked by the scheduler.
In addition, high level interrupt handlers must take care to do a mini‐
mum of work because they are not preemptable.
A typical high level interrupt handler would put data into a circular
buffer and schedule a soft interrupt by calling ddi_trigger_softintr().
The circular buffer could be protected by using a mutex that was prop‐
erly initialized for the interrupt handler.
The ddi_intr_hilevel() function can be used before calling
ddi_add_intr() to decide which type of interrupt handler should be
used. Most device drivers are designed with the knowledge that the
devices they support will always generate low level interrupts, however
some devices, for example those using SBus or VME bus level 6 or 7
interrupts must use this test because on some machines those interrupts
are high level (above the scheduler level) and on other machines they
are not.
RETURN VALUES
non-zero indicates a high-level interrupt.
CONTEXT
These functions can be called from useruser, interrupt, or kernel con‐
text.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Obsolete │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOddi_add_intr(9F), Intro(9F), mutex(9F)
Writing Device Drivers
SunOS 5.10 16 Jan 2006 ddi_intr_hilevel(9F)