Libfuse basically creates a new thread for each new request. This is fine for
synchronous requests, which are naturally limited. However background
requests (especially writepage) can cause a thread creation storm.
To avoid this, limit the number of background requests available to userspace.
This is done by introducing another queue for background requests, and a
counter for the number of "active" requests, which are currently available for
userspace.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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