cvs commit: src/sys/vm vm_kern.c

[Dag-ErlingSmørgrav]

Robert Watson <rwatson at FreeBSD.org> writes:
> On Mon, 16 Feb 2004, Dag-Erling Smorgrav wrote:
> >   Log:
> >   Don't panic if we fail to satisfy an M_WAITOK request; return 0 instead.
> >   The calling code will either handle that gracefully or cause a page fault.
> This substantially modifies the semantics of the two consumers of
> kmem_malloc(), and those semantic changes trickle up the stack to a number
> of important places.  Are you going to update the consumers (and their
> comments) as well?

This can only happen if you request a ridiculously large allocation;
if you actually run out of memory (e.g. due to a leak) you will get
"out of swap space" or similar errors instead.  There are several
cases in which kmem_malloc() would previously trigger "kmem_map too
small" even though the caller could recover gracefully if given half a
chance.  Before this patch there was no incentive to fix those cases
because you'd never get a change to try to recover anyway.

DES
-- 
Dag-Erling Smørgrav - des at des.no