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sync_instruction_memory(3c) [opensolaris man page]

sync_instruction_memory(3C)				   Standard C Library Functions 			       sync_instruction_memory(3C)

NAME
sync_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_instruction_memory() function performs this function, and/or any other functions needed to make modified instructions between addr and addr+len visible. 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 function 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. 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 ALSO
attributes(5) SunOS 5.11 12 Feb 1997 sync_instruction_memory(3C)

Check Out this Related Man Page

CACHEFLUSH(2)						     Linux Programmer's Manual						     CACHEFLUSH(2)

NAME
cacheflush - flush contents of instruction and/or data cache SYNOPSIS
#include <asm/cachectl.h> int cacheflush(char *addr, int nbytes, int cache); DESCRIPTION
cacheflush() flushes the contents of the indicated cache(s) for the user addresses in the range addr to (addr+nbytes-1). cache may be one of: ICACHE Flush the instruction cache. DCACHE Write back to memory and invalidate the affected valid cache lines. BCACHE Same as (ICACHE|DCACHE). RETURN VALUE
cacheflush() returns 0 on success or -1 on error. If errors are detected, errno will indicate the error. ERRORS
EFAULT Some or all of the address range addr to (addr+nbytes-1) is not accessible. EINVAL cache is not one of ICACHE, DCACHE, or BCACHE (but see BUGS). CONFORMING TO
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 standard. Caveat cacheflush() 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 cacheflush() system call on some other architectures, but with different arguments. BUGS
Linux kernels older than version 2.6.11 ignore the addr and nbytes arguments, making this function fairly expensive. Therefore, the whole cache is always flushed. This function always behaves as if BCACHE has been passed for the cache argument and does not do any error checking on the cache argument. COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/. Linux 2017-09-15 CACHEFLUSH(2)
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