sync_instruction_memory(3Standard C Library Functiosync_instruction_memory(3C)NAMEsync_instruction_memory - make modified instructions executable
SYNOPSIS
void sync_instruction_memory(caddr_t addr, int len);
DESCRIPTION
The sync_instruction_memory() function performs whatever steps are
required to make instructions modified by a program executable.
Some processor architectures, including some SPARC processors, have
separate and independent instruction and data caches which are not kept
consistent by hardware. For example, if the instruction cache contains
an instruction from some address and the program then stores a new
instruction at that address, the new instruction may not be immediately
visible to the instruction fetch mechanism. Software must explicitly
invalidate the instruction cache entries for new or changed mappings of
pages that might contain executable instructions. The sync_instruc‐
tion_memory() function performs this function, and/or any other func‐
tions needed to make modified instructions between addr and addr+len
visible. A program should call sync_instruction_memory() after modify‐
ing instructions and before executing them.
On processors with unified caches (one cache for both instructions and
data) and pipelines which are flushed by a branch instruction, such as
the x86 architecture, the function may do nothing and just return.
The changes are immediately visible to the thread calling sync_instruc‐
tion_memory() when the call returns, even if the thread should migrate
to another processor during or after the call. The changes become visi‐
ble to other threads in the same manner that stores do; that is, they
eventually become visible, but the latency is implementation-dependent.
The result of executing sync_instruction_memory() are unpredictable if
addr through addr+len-1 are not valid for the address space of the pro‐
gram making the call.
RETURN VALUES
No values are returned.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOattributes(5)SunOS 5.10 12 Feb 1997 sync_instruction_memory(3C)
