Section: Linux Programmer's Manual (2)
cacheflush - flush contents of instruction and/or data cache
int cacheflush(char *addr, int nbytes, int cache);
flushes the contents of the indicated cache(s) for the
user addresses in the range
may be one of:
Flush the instruction cache.
Write back to memory and invalidate the affected valid cache lines.
returns 0 on success or -1 on error.
If errors are detected,
will indicate the error.
Some or all of the address range
is not accessible.
is not one of
(but see BUGS).
Historically, this system call was available on all MIPS UNIX variants
including RISC/os, IRIX, Ultrix, NetBSD, OpenBSD, and FreeBSD
(and also on some non-UNIX MIPS operating systems), so that
the existence of this call in MIPS operating systems is a de-facto
should not be used in programs intended to be portable.
On Linux, this call first appeared on the MIPS architecture,
but nowadays, Linux provides a
system call on some other architectures, but with different arguments.
Linux kernels older than version 2.6.11 ignore the
arguments, making this function fairly expensive.
Therefore, the whole cache is always flushed.
This function always behaves as if
has been passed for the
argument and does not do any error checking on the
This page is part of release 5.02 of the Linux
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