From owner-freebsd-hackers@freebsd.org  Mon Jul  9 06:27:09 2018
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From: Pratyush Yadav <pratyush@freebsd.org>
Date: Mon, 9 Jul 2018 11:51:02 +0530
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Subject: Can contigmalloc(9) fail even when M_NOWAIT is *not* specified?
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Hi,

The contigmalloc(9) man page says:

> The contigmalloc() function does not sleep waiting for memory resources
> to be freed up, but instead actively reclaims pages before giving up.
> However, unless M_NOWAIT is specified, it may select a page for reclama-
> tion that must first be written to backing storage, causing it to sleep.

So if M_NOWAIT is *not* specified, can contigmalloc() "give up", and
return NULL?

-- 
Regards,
Pratyush Yadav