Noticed while attempting to make boolean_t unsigned: some vm-related
function declarations and defintions were using boolean_t where they
should have used int, and vice versa.
MFC after: 1 week
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D39753
also make it return the count of the swap pages freed, which are not
simultaneously resident in the object.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D37097
We don't need to hold the object lock while allocating swap space, so
don't.
Reviewed by: dougm, kib, markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D35839
With the removal of OBJT_DEFAULT, we can simply handle this in
swap_pager_dealloc(). No functional change intended.
Suggested by: alc
Reviewed by: alc, kib
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35787
With the removal of OBJT_DEFAULT, we can assume that pager operations
provide an object with OBJ_SWAP set. Also, we do not need to convert
objects from type OBJT_DEFAULT. Thus, remove checks for OBJ_SWAP and
remove code which modifies the object type. In some places, replace the
check for OBJ_SWAP with a check for whether any swap blocks are
assigned.
Reviewed by: alc, kib
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35786
The correct OID format for CTLTYPE_U64 is `QU` (`uquad_t`), not `A`
(text expressed via `char *`).
This issue was noticed while doing an sysctl tree walk using a
sysctl(9) consumer that relies on the OID format to intuit what the
type should be for a given sysctl.
MFC after: 1 month
Sponsored by: DellEMC Isilon
Differential Revision: https://reviews.freebsd.org/D34877
Remove always-false checks for UMA zone creation failure. No functional
change intended.
Reviewed by: alc, kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33809
The flag requests skipping the heuristic which tries to avoid leaving
system with more allocated memory than available from RAM and remanining
swap.
Reviewed by: markj
Discussed with: alc
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33165
For compatibility, add a placeholder pointer to the start of the
added struct swapoff_new_args, and use it to distinguish old vs. new
style of syscall invocation.
Reviewed by: markj
Discussed with: alc
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33165
When swap is turned off due to system shutdown or reboot, ignore the
check. Problem is that the check is not accurate by any means, free
page count can legitimately be low while system still able to page in
everything from the swap. Then, we turn swap off if swapping on
real file or some non-standard geom provider, and typically panic
when system appears to actually need to unavailable page.
For syscall, it is better to be safe than sorry.
Reported and tested by: peterj
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33147
VOP_STRATEGY() requires locked vnode. Note that we lock the swap vnode
while pages are busy, but this would only cause real LoR if pages belong
to the swap vnode, which must not be the case for correct use.
Reported and tested by: peterj
Reviewed by: markj
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33119
to cover VOP_GETATTR() call in sys_swapon(). Move locking from inside
swapongeom() and swaponvp() into sys_swapon().
Reported by and tested by: peterj
Reviewed by: markj
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33119
GEOM_ELI needs to know the value, cause it will soon have special
memory handling for IO operations associated with swap.
Move initialization to swap_pager_init(), which is executed at
SI_SUB_VM, unlike swap_pager_swap_init(), which would be executed
only when a swap is configured. GEOM_ELI might need the value at
SI_SUB_DRIVERS, when disks are tasted by GEOM.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D24400
This interface is used solely by md(4) when the MD_RESERVE flag is
specified, as in `mdconfig -a -t swap -s 1G -o reserve`. It
pre-allocates swap blocks for the entire object.
The number of blocks to be reserved is specified as a vm_size_t, but
swp_pager_getswapspace() can allocate at most INT_MAX blocks. vm_size_t
also seems like the incorrect type to use here it refers only to the
size of the VM object, not the size of a mapping. So:
- change the type of "size" in swap_pager_reserve() to vm_pindex_t, and
- clamp the requested number of blocks for a single
swp_pager_getswapspace() call to INT_MAX.
Reported by: syzkaller
Reviewed by: dougm, alc, kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31875
Remove OBJT_SWAP_TMPFS. Move tmpfs-specific swap pager bits into
tmpfs_subr.c.
There is no longer any code to directly support tmpfs in sys/vm, most
tmpfs knowledge is shared by non-anon swap object type implementation.
The tmpfs-specific methods are provided by registered tmpfs pager, which
inherits from the swap pager.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30168
This is OBJT_SWAP pager, specialized for tmpfs. Right now, both swap pager
and generic vm code have to explicitly handle swap objects which are tmpfs
vnode v_object, in the special ways. Replace (almost) all such places with
proper methods.
Since VM still needs a notion of the 'swap object', regardless of its
use, add yet another type-classification flag OBJ_SWAP. Set it in
vm_object_allocate() where other type-class flags are set.
This change almost completely eliminates the knowledge of tmpfs from VM,
and opens a way to make OBJT_SWAP_TMPFS loadable from tmpfs.ko.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30070
Allow vp_heldp argument to be NULL, in which case the returned vnode
is not held for tmpfs swap objects.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30070
Makes the code in vm_object collapse/page_remove cleaner
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30070
This eliminates the staircase of conditions in vm_map_entry_set_vnode_text().
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30070
specialized for swap and vnode pagers, and used to implement
vm_object_set_writeable_dirty().
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30070
For anonymous objects, provide a handle kvo_me naming the object,
and report the handle of the backing object. This allows userspace
to deconstruct the shadow chain. Right now the handle is the address
of the object in KVA, but this is not guaranteed.
For the same anonymous objects, report the swap space used for actually
swapped out pages, in kvo_swapped field. I do not believe that it is
useful to report full 64bit counter there, so only uint32_t value is
returned, clamped to the max.
For kinfo_vmentry, report anonymous object handle backing the entry,
so that the shadow chain for the specific mapping can be deconstructed.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29771
Replace MAXPHYS by runtime variable maxphys. It is initialized from
MAXPHYS by default, but can be also adjusted with the tunable kern.maxphys.
Make b_pages[] array in struct buf flexible. Size b_pages[] for buffer
cache buffers exactly to atop(maxbcachebuf) (currently it is sized to
atop(MAXPHYS)), and b_pages[] for pbufs is sized to atop(maxphys) + 1.
The +1 for pbufs allow several pbuf consumers, among them vmapbuf(),
to use unaligned buffers still sized to maxphys, esp. when such
buffers come from userspace (*). Overall, we save significant amount
of otherwise wasted memory in b_pages[] for buffer cache buffers,
while bumping MAXPHYS to desired high value.
Eliminate all direct uses of the MAXPHYS constant in kernel and driver
sources, except a place which initialize maxphys. Some random (and
arguably weird) uses of MAXPHYS, e.g. in linuxolator, are converted
straight. Some drivers, which use MAXPHYS to size embeded structures,
get private MAXPHYS-like constant; their convertion is out of scope
for this work.
Changes to cam/, dev/ahci, dev/ata, dev/mpr, dev/mpt, dev/mvs,
dev/siis, where either submitted by, or based on changes by mav.
Suggested by: mav (*)
Reviewed by: imp, mav, imp, mckusick, scottl (intermediate versions)
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D27225
swap size by dividing a value, which was always a multiple of 64, by
64. Remove the code that reduced max swap size down to that cap.
Eliminate the distinction between BLIST_BMAP_RADIX and
BLIST_META_RADIX. Call them both BLIST_RADIX.
Make improvments to the blist self-test code to silence compiler
warnings and to test larger blists.
Reported by: jmallett
Reviewed by: alc
Discussed with: kib
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D25736
The code did not subtract from the global counter if per-uid reservation
failed.
Cleanup highlights:
- load overcommit once
- move per-uid manipulation to dedicated routines
- don't fetch wire count if requested size is below the limit
- convert return type from int to bool
- ifdef the routines with _KERNEL to keep vm.h compilable by userspace
Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D25787
The counter keeps being updated all the time and variables read afterwards
share the cacheline. Note this still fundamentally does not scale and needs
to be replaced, in the meantime gets a bandaid.
brk1_processes -t 52 ops/s:
before: 8598298
after: 9098080
The lock-protected iteration is trivially avoidable.
This removes a serialisation point from Linux binaries (which end up calling
here from the sysinfo syscall).
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
The minimum allocation size of 4 blocks is an old policy that came with
the "new" swap pager in r42957. Since then the blist allocator has
gotten better at reducing fragmentation; for example, with r349777 it
can return a range that spans multiple leaves. When swap space is close
to being exhaused, the minimum of 4 blocks most likely exacerbates
memory pressure, so reduce it to 1.
Reported by: alc
Tested by: pho
Reviewed by: alc, dougm, kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23763
virtual address or physical page allocation need to be marked with this
flag.
Reviewed by: markj
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D23712
