sync_instruction_memory - make modified instructions execut-
void sync_instruction_memory(caddr_t addr, int len);
The sync_instruction_memory() function performs whatever
steps are required to make instructions modified by a pro-
Some processor architectures, including some SPARC proces-
sors, have separate and independent instruction and data
caches which are not kept consistent by hardware. For exam-
ple, 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_instruction_memory() function per-
forms this function, and/or any other functions needed to
make modified instructions between addr and addr+len visi-
ble. A program should call sync_instruction_memory() after
modifying 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 func-
tion may do nothing and just return.
The changes are immediately visible to the thread calling
sync_instruction_memory() when the call returns, even if the
thread should migrate to another processor during or after
the call. The changes become visible 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 program making the call.
No values are returned.
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| MT-Level | MT-Safe |
Man(1) output converted with