CACHE(3) BSD Library Functions Manual CACHE(3)

NAME
     ssyyssccaacchheeccoonnttrrooll, ssyyssiiccaacchheeiinnvvaalliiddaattee, ssyyssddccaacchheefflluusshh - cache con-
     trol

LLIIBBRRAARRYY
     Standard C Library (libc, -lc)

SYNOPSIS
     ##iinncclluuddee <>

     int
     ssyyssccaacchheeccoonnttrrooll(int function, void *start, sizet len);

     void
     ssyyssiiccaacchheeiinnvvaalliiddaattee(void *start, sizet len);

     void
     ssyyssddccaacchheefflluusshh(void *start, sizet len);

DESCRIPTION
     These functions operate on every cache line containing one of the len
     bytes of memory pointed to by start.  Normally the operations apply to
     every processor in the system, but the exact semantics of these opera-
     tions is platform dependent.  They should be used with caution.

     ssyyssccaacchheeccoonnttrrooll() performs the operation specified by function.  Refer
     to the header file for a list of currently supported functions.

     ssyyssiiccaacchheeiinnvvaalliiddaattee() prepares memory for execution, typically by
     invalidating the instruction cache for the indicated range.  This should
     be called after writing machine instructions to memory, and before exe-
     cuting them.  On IA32 processors this function is a NOP, because their
     instruction caches are coherent.

     ssyyssddccaacchheefflluusshh() writes modified data cache lines to main memory, and
     then invalidates all lines in the range being operated on.  It can be
     useful when dealing with cache incoherent devices or DMA.

RETURN VALUES
     ssyyssccaacchheeccoonnttrrooll() returns zero on success, ENOTSUP if function is not
     valid.

SEE ALSO
     atomic(3), barrier(3)

HISTORY     These functions first appeared in Mac OS 10.5 (Leopard).

Darwin                        September 21, 2006                        Darwin