deal with shortages of the VM maps where the backing pages are mapped
(usually kmem_map). Try to deal with this:
* Group all information about the backend allocator for a pool in a
separate structure. The pool references this structure, rather than
the individual fields.
* Change the pool_init() API accordingly, and adjust all callers.
* Link all pools using the same backend allocator on a list.
* The backend allocator is responsible for waiting for physical memory
to become available, but will still fail if it cannot callocate KVA
space for the pages. If this happens, carefully drain all pools using
the same backend allocator, so that some KVA space can be freed.
* Change pool_reclaim() to indicate if it actually succeeded in freeing
some pages, and use that information to make draining easier and more
efficient.
* Get rid of PR_URGENT. There was only one use of it, and it could be
dealt with by the caller.
From art@openbsd.org.
rounded up to respect boundary limits, adjust newstart and last before
skiping to the next region. Otherwise we may check the same candidate
region against the start of the next region, no the one immediatly following
the hole, leading to corrupted map.
This fixes the panic seen on sparc64 with scsi drivers, and probably fixes
PR 15489.
check that newstart + size - 1 doesn't overflow the end of the extent, rather
than the "dontcross" value, which can easily overflow the end of an extent
when being asked for an object with a large boundary requirement. this test
is more valid, in any case, and fixes extent_alloc() failure when the start of
the extent is not "aligned".
<vm/pglist.h> -> <uvm/uvm_pglist.h>
<vm/vm_inherit.h> -> <uvm/uvm_inherit.h>
<vm/vm_kern.h> -> into <uvm/uvm_extern.h>
<vm/vm_object.h> -> nothing
<vm/vm_pager.h> -> into <uvm/uvm_pager.h>
also includes a bunch of <vm/vm_page.h> include removals (due to redudancy
with <vm/vm.h>), and a scattering of other similar headers.
Change #define's of the form
#define panic(a) printf(a)
to
#define \
panic(a) printf(a)
to prevent ctags(1) from detecting there is a tag.
Otherwise, the tags file claims panic() is in subr_extent.c
instead of subr_prf.c.
-a subregion start was ignored if all previous allocations were before
the subregion, reported by Lennart Augustsson in PR kern/7539
-an existing allocation which overlaps the beginning of the subregion
was ignored (ie overlapped) if is is not the last allocation
Also:
* Do the boundary check when creating a new region as well.
* If we crossed the boundary, don't just throw away the region; lop off the
beginning and see if we still fit.
SB16 is now fully functional on the Alpha.
number modulo the given alignment.
To do this the function extent_alloc_subregion() takes an additional `skew'
parameter. For compatibility's sake, this function has been renamed to
extent_alloc_subregion1().
(1): "substart == ex->ex_end" and "subend == ex->ex_start"
are completely legal parameters for extent_alloc_subregion()
(2): "(subend - substart) + 1" can cause an overflow if the whole
numeric range is covered by the extent.
Submitted by Matthias Drochner <drochner@zelz26.zel.kfa-juelich.de>
in PR #3119.
If not compiled with -D_KERNEL, include different includes and
do so macro magic so that this will fit sanely into test harnesses.
When used in user-land, this should be compiled with -D_EXTENT_TESTING.
Bug fixes:
(extent_insert_and_optimize) You can't do things like:
LIST_REMOVE(elem->...le_next, ...);
free(elem->...le_next, ...);
They just don't work (and will corrupt your list and/or malloc free list).
(extent_alloc_region_descriptor) Unless you wait, malloc can fail.
Don't accidentally deref a potentially-NULL pointer.
- Rename EX_NOBLOB to EX_NOCOALESCE; it's much more descriptive of
what's going on.
- In extent_free_region_descriptor(), if we're a fixed extent,
freeing a dynamically allocated region descriptor, and someone
is waiting on the freelist, let the waiter have it, rather than
free'ing it back to the system.
- Use ALIGN(), rather than our homegrown EXTENT_ALIGN(), when dealing
with map overhead. Privatize the EXTENT_ALIGN() macro; there's no need
to export it.
- Implement EX_BOUNDZERO flag. This changes the boundary line policy in
extent_alloc() and extent_alloc_subregion(); boundary lines are
computed relative to 0, rather then the start of the extent.
- Fix a nasty race between multiple participants doing region and
descriptor allocation.
- Add a new flag to specify that it's ok to wait for space in the
extent: EX_WAITSPACE.
- Blow away an unnecessary splhigh()/splx().
- Put a bunch of sanity code inside #ifdef DIAGNOSTIC/#endif.
Understands allocation aligment and boundary restrictions, "specific region"
allocations, and suballocations. Capable of statically or dynamically
allocating map overhead.
Many thanks to Matthias Drochner for running the code for me, and sending
me bug fixes, optimizations, and suggestions. Also, many thanks to
Chris Demetriou for his extremely helpful suggestions.
XXX No manual page yet. One is forthcoming, as soon as I can scare up
the time to write one. This has been sitting on my plate for quite a
while, and several projects are waiting for it. Time to move on.
thorpej