Commit Graph

466 Commits

Author SHA1 Message Date
Minchan Kim
c6bc1396ce FROMLIST: mm: replace migrate_[prep|finish] with lru_cache_[disable|enable]
Currently, migrate_[prep|finish] is merely a wrapper of
lru_cache_[disable|enable]. There is not much to gain from
having additional abstraction.

Use lru_cache_[disable|enable] instead of migrate_[prep|finish],
which would be more descriptive.

note: migrate_prep_local in compaction.c changed into lru_add_drain
to avoid CPU schedule cost with involving many other CPUs to keep
keep old behavior.

Bug: 180018981
Link: https://lore.kernel.org/linux-mm/20210319175127.886124-2-minchan@kernel.org/
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I2f298c9ff53c8693527f1207ff25ab76a4ac3ada
2021-03-23 04:05:24 +00:00
Minchan Kim
68a4731181 BACKPORT: FROMLIST: mm: disable LRU pagevec during the migration temporarily
LRU pagevec holds refcount of pages until the pagevec are drained.
It could prevent migration since the refcount of the page is greater
than the expection in migration logic. To mitigate the issue,
callers of migrate_pages drains LRU pagevec via migrate_prep or
lru_add_drain_all before migrate_pages call.

However, it's not enough because pages coming into pagevec after the
draining call still could stay at the pagevec so it could keep
preventing page migration. Since some callers of migrate_pages have
retrial logic with LRU draining, the page would migrate at next trail
but it is still fragile in that it doesn't close the fundamental race
between upcoming LRU pages into pagvec and migration so the migration
failure could cause contiguous memory allocation failure in the end.

To close the race, this patch disables lru caches(i.e, pagevec)
during ongoing migration until migrate is done.

Since it's really hard to reproduce, I measured how many times
migrate_pages retried with force mode(it is about a fallback to a
sync migration) with below debug code.

int migrate_pages(struct list_head *from, new_page_t get_new_page,
			..
			..

if (rc && reason == MR_CONTIG_RANGE && pass > 2) {
       printk(KERN_ERR, "pfn 0x%lx reason %d\n", page_to_pfn(page), rc);
       dump_page(page, "fail to migrate");
}

The test was repeating android apps launching with cma allocation
in background every five seconds. Total cma allocation count was
about 500 during the testing. With this patch, the dump_page count
was reduced from 400 to 30.

The new interface is also useful for memory hotplug which currently
drains lru pcp caches after each migration failure. This is rather
suboptimal as it has to disrupt others running during the operation.
With the new interface the operation happens only once. This is also in
line with pcp allocator cache which are disabled for the offlining as
well.

Bug: 180018981
Link: https://lore.kernel.org/linux-mm/20210319175127.886124-1-minchan@kernel.org/
Reviewed-by: Chris Goldsworthy <cgoldswo@codeaurora.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I838c63d11ca49a8734d8b37a7d5272ab6b802f9f
2021-03-23 04:05:15 +00:00
Minchan Kim
d3c1bf42af Revert "FROMLIST: mm: replace migrate_prep with lru_add_drain_all"
This reverts commit 134ac2d4dc.

Bug: 180018981
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I579c72398447f770c235e4fefd246f1dbbd250d0
2021-03-23 04:05:07 +00:00
Minchan Kim
7ed55d7025 Revert "BACKPORT: FROMLIST: mm: disable LRU pagevec during the migration temporarily"
This reverts commit 3039d8580c.

Bug: 180018981
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: Iadadd7f4c7aafa439afd7a1c3e575e5e31602bef
2021-03-23 04:04:58 +00:00
Minchan Kim
3039d8580c BACKPORT: FROMLIST: mm: disable LRU pagevec during the migration temporarily
LRU pagevec holds refcount of pages until the pagevec are drained.
It could prevent migration since the refcount of the page is greater
than the expection in migration logic. To mitigate the issue,
callers of migrate_pages drains LRU pagevec via migrate_prep or
lru_add_drain_all before migrate_pages call.

However, it's not enough because pages coming into pagevec after the
draining call still could stay at the pagevec so it could keep
preventing page migration. Since some callers of migrate_pages have
retrial logic with LRU draining, the page would migrate at next trail
but it is still fragile in that it doesn't close the fundamental race
between upcoming LRU pages into pagvec and migration so the migration
failure could cause contiguous memory allocation failure in the end.

To close the race, this patch disables lru caches(i.e, pagevec)
during ongoing migration until migrate is done.

Since it's really hard to reproduce, I measured how many times
migrate_pages retried with force mode(it is about a fallback to a
sync migration) with below debug code.

int migrate_pages(struct list_head *from, new_page_t get_new_page,
			..
			..

if (rc && reason == MR_CONTIG_RANGE && pass > 2) {
       printk(KERN_ERR, "pfn 0x%lx reason %d\n", page_to_pfn(page), rc);
       dump_page(page, "fail to migrate");
}

The test was repeating android apps launching with cma allocation
in background every five seconds. Total cma allocation count was
about 500 during the testing. With this patch, the dump_page count
was reduced from 400 to 30.

The new interface is also useful for memory hotplug which currently
drains lru pcp caches after each migration failure. This is rather
suboptimal as it has to disrupt others running during the operation.
With the new interface the operation happens only once. This is also in
line with pcp allocator cache which are disabled for the offlining as
well.

Bug: 180018981
Link: https://lore.kernel.org/linux-mm/20210310161429.399432-2-minchan@kernel.org/
[minchan: Resolved conflict in mm/memory_hotplug.c, mm/swap.c]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: Ie1e09cf26e3105b674a9aed4ac65070efee608af
2021-03-12 12:35:53 -08:00
Minchan Kim
134ac2d4dc FROMLIST: mm: replace migrate_prep with lru_add_drain_all
Currently, migrate_prep is merely a wrapper of lru_cache_add_all.
There is not much to gain from having additional abstraction.

Use lru_add_drain_all instead of migrate_prep, which would be more
descriptive.

note: migrate_prep_local in compaction.c changed into lru_add_drain
to avoid CPU schedule cost with involving many other CPUs to keep
keep old behavior.

Bug: 180018981
Link: https://lore.kernel.org/linux-mm/20210310161429.399432-1-minchan@kernel.org/
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I1bd3fcb13993e8a7a7961ceec817ac17304364cb
2021-03-12 12:35:53 -08:00
Yang Shi
059eaf82c0 UPSTREAM: mm: migrate: clean up migrate_prep{_local}
The migrate_prep{_local} never fails, so it is pointless to have return
value and check the return value.

Bug: 180018981
Link: https://lkml.kernel.org/r/20201113205359.556831-5-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 236c32eb109696590b7428957eda50cc05e22af8)
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I26ae0a4240c704e6127b51532e5de8ba778edd6e
2021-03-12 12:35:52 -08:00
Greg Kroah-Hartman
ba152773be Merge 5.10.11 into android12-5.10
Changes in 5.10.11
	scsi: target: tcmu: Fix use-after-free of se_cmd->priv
	mtd: rawnand: gpmi: fix dst bit offset when extracting raw payload
	mtd: rawnand: nandsim: Fix the logic when selecting Hamming soft ECC engine
	i2c: tegra: Wait for config load atomically while in ISR
	i2c: bpmp-tegra: Ignore unknown I2C_M flags
	platform/x86: i2c-multi-instantiate: Don't create platform device for INT3515 ACPI nodes
	platform/x86: ideapad-laptop: Disable touchpad_switch for ELAN0634
	ALSA: seq: oss: Fix missing error check in snd_seq_oss_synth_make_info()
	ALSA: hda/realtek - Limit int mic boost on Acer Aspire E5-575T
	ALSA: hda/via: Add minimum mute flag
	crypto: xor - Fix divide error in do_xor_speed()
	dm crypt: fix copy and paste bug in crypt_alloc_req_aead
	ACPI: scan: Make acpi_bus_get_device() clear return pointer on error
	btrfs: don't get an EINTR during drop_snapshot for reloc
	btrfs: do not double free backref nodes on error
	btrfs: fix lockdep splat in btrfs_recover_relocation
	btrfs: don't clear ret in btrfs_start_dirty_block_groups
	btrfs: send: fix invalid clone operations when cloning from the same file and root
	fs: fix lazytime expiration handling in __writeback_single_inode()
	pinctrl: ingenic: Fix JZ4760 support
	mmc: core: don't initialize block size from ext_csd if not present
	mmc: sdhci-of-dwcmshc: fix rpmb access
	mmc: sdhci-xenon: fix 1.8v regulator stabilization
	mmc: sdhci-brcmstb: Fix mmc timeout errors on S5 suspend
	dm: avoid filesystem lookup in dm_get_dev_t()
	dm integrity: fix a crash if "recalculate" used without "internal_hash"
	dm integrity: conditionally disable "recalculate" feature
	drm/atomic: put state on error path
	drm/syncobj: Fix use-after-free
	drm/amdgpu: remove gpu info firmware of green sardine
	drm/amd/display: DCN2X Find Secondary Pipe properly in MPO + ODM Case
	drm/i915/gt: Prevent use of engine->wa_ctx after error
	drm/i915: Check for rq->hwsp validity after acquiring RCU lock
	ASoC: Intel: haswell: Add missing pm_ops
	ASoC: rt711: mutex between calibration and power state changes
	SUNRPC: Handle TCP socket sends with kernel_sendpage() again
	HID: multitouch: Enable multi-input for Synaptics pointstick/touchpad device
	HID: sony: select CONFIG_CRC32
	dm integrity: select CRYPTO_SKCIPHER
	x86/hyperv: Fix kexec panic/hang issues
	scsi: ufs: Relax the condition of UFSHCI_QUIRK_SKIP_MANUAL_WB_FLUSH_CTRL
	scsi: ufs: Correct the LUN used in eh_device_reset_handler() callback
	scsi: qedi: Correct max length of CHAP secret
	scsi: scsi_debug: Fix memleak in scsi_debug_init()
	scsi: sd: Suppress spurious errors when WRITE SAME is being disabled
	riscv: Fix kernel time_init()
	riscv: Fix sifive serial driver
	riscv: Enable interrupts during syscalls with M-Mode
	HID: logitech-dj: add the G602 receiver
	HID: Ignore battery for Elan touchscreen on ASUS UX550
	clk: tegra30: Add hda clock default rates to clock driver
	ALSA: hda/tegra: fix tegra-hda on tegra30 soc
	riscv: cacheinfo: Fix using smp_processor_id() in preemptible
	arm64: make atomic helpers __always_inline
	xen: Fix event channel callback via INTX/GSI
	x86/xen: Add xen_no_vector_callback option to test PCI INTX delivery
	x86/xen: Fix xen_hvm_smp_init() when vector callback not available
	dts: phy: fix missing mdio device and probe failure of vsc8541-01 device
	dts: phy: add GPIO number and active state used for phy reset
	riscv: defconfig: enable gpio support for HiFive Unleashed
	drm/amdgpu/psp: fix psp gfx ctrl cmds
	drm/amd/display: disable dcn10 pipe split by default
	HID: logitech-hidpp: Add product ID for MX Ergo in Bluetooth mode
	drm/amd/display: Fix to be able to stop crc calculation
	drm/nouveau/bios: fix issue shadowing expansion ROMs
	drm/nouveau/privring: ack interrupts the same way as RM
	drm/nouveau/i2c/gm200: increase width of aux semaphore owner fields
	drm/nouveau/mmu: fix vram heap sizing
	drm/nouveau/kms/nv50-: fix case where notifier buffer is at offset 0
	io_uring: flush timeouts that should already have expired
	libperf tests: If a test fails return non-zero
	libperf tests: Fail when failing to get a tracepoint id
	RISC-V: Set current memblock limit
	RISC-V: Fix maximum allowed phsyical memory for RV32
	x86/xen: fix 'nopvspin' build error
	nfsd: Fixes for nfsd4_encode_read_plus_data()
	nfsd: Don't set eof on a truncated READ_PLUS
	gpiolib: cdev: fix frame size warning in gpio_ioctl()
	pinctrl: aspeed: g6: Fix PWMG0 pinctrl setting
	pinctrl: mediatek: Fix fallback call path
	RDMA/ucma: Do not miss ctx destruction steps in some cases
	btrfs: print the actual offset in btrfs_root_name
	scsi: megaraid_sas: Fix MEGASAS_IOC_FIRMWARE regression
	scsi: ufs: ufshcd-pltfrm depends on HAS_IOMEM
	scsi: ufs: Fix tm request when non-fatal error happens
	crypto: omap-sham - Fix link error without crypto-engine
	bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach
	powerpc: Use the common INIT_DATA_SECTION macro in vmlinux.lds.S
	powerpc: Fix alignment bug within the init sections
	arm64: entry: remove redundant IRQ flag tracing
	bpf: Reject too big ctx_size_in for raw_tp test run
	drm/amdkfd: Fix out-of-bounds read in kdf_create_vcrat_image_cpu()
	RDMA/umem: Avoid undefined behavior of rounddown_pow_of_two()
	RDMA/cma: Fix error flow in default_roce_mode_store
	printk: ringbuffer: fix line counting
	printk: fix kmsg_dump_get_buffer length calulations
	iov_iter: fix the uaccess area in copy_compat_iovec_from_user
	i2c: octeon: check correct size of maximum RECV_LEN packet
	drm/vc4: Unify PCM card's driver_name
	platform/x86: intel-vbtn: Drop HP Stream x360 Convertible PC 11 from allow-list
	platform/x86: hp-wmi: Don't log a warning on HPWMI_RET_UNKNOWN_COMMAND errors
	gpio: sifive: select IRQ_DOMAIN_HIERARCHY rather than depend on it
	ALSA: hda: Balance runtime/system PM if direct-complete is disabled
	xsk: Clear pool even for inactive queues
	selftests: net: fib_tests: remove duplicate log test
	can: dev: can_restart: fix use after free bug
	can: vxcan: vxcan_xmit: fix use after free bug
	can: peak_usb: fix use after free bugs
	perf evlist: Fix id index for heterogeneous systems
	i2c: sprd: depend on COMMON_CLK to fix compile tests
	iio: common: st_sensors: fix possible infinite loop in st_sensors_irq_thread
	iio: ad5504: Fix setting power-down state
	drivers: iio: temperature: Add delay after the addressed reset command in mlx90632.c
	iio: adc: ti_am335x_adc: remove omitted iio_kfifo_free()
	counter:ti-eqep: remove floor
	powerpc/64s: fix scv entry fallback flush vs interrupt
	cifs: do not fail __smb_send_rqst if non-fatal signals are pending
	irqchip/mips-cpu: Set IPI domain parent chip
	x86/fpu: Add kernel_fpu_begin_mask() to selectively initialize state
	x86/topology: Make __max_die_per_package available unconditionally
	x86/mmx: Use KFPU_387 for MMX string operations
	x86/setup: don't remove E820_TYPE_RAM for pfn 0
	proc_sysctl: fix oops caused by incorrect command parameters
	mm: memcg/slab: optimize objcg stock draining
	mm: memcg: fix memcg file_dirty numa stat
	mm: fix numa stats for thp migration
	io_uring: iopoll requests should also wake task ->in_idle state
	io_uring: fix SQPOLL IORING_OP_CLOSE cancelation state
	io_uring: fix short read retries for non-reg files
	intel_th: pci: Add Alder Lake-P support
	stm class: Fix module init return on allocation failure
	serial: mvebu-uart: fix tx lost characters at power off
	ehci: fix EHCI host controller initialization sequence
	USB: ehci: fix an interrupt calltrace error
	usb: gadget: aspeed: fix stop dma register setting.
	USB: gadget: dummy-hcd: Fix errors in port-reset handling
	usb: udc: core: Use lock when write to soft_connect
	usb: bdc: Make bdc pci driver depend on BROKEN
	usb: cdns3: imx: fix writing read-only memory issue
	usb: cdns3: imx: fix can't create core device the second time issue
	xhci: make sure TRB is fully written before giving it to the controller
	xhci: tegra: Delay for disabling LFPS detector
	drivers core: Free dma_range_map when driver probe failed
	driver core: Fix device link device name collision
	driver core: Extend device_is_dependent()
	drm/i915: s/intel_dp_sink_dpms/intel_dp_set_power/
	drm/i915: Only enable DFP 4:4:4->4:2:0 conversion when outputting YCbCr 4:4:4
	x86/entry: Fix noinstr fail
	x86/cpu/amd: Set __max_die_per_package on AMD
	cls_flower: call nla_ok() before nla_next()
	netfilter: rpfilter: mask ecn bits before fib lookup
	tools: gpio: fix %llu warning in gpio-event-mon.c
	tools: gpio: fix %llu warning in gpio-watch.c
	drm/i915/hdcp: Update CP property in update_pipe
	sh: dma: fix kconfig dependency for G2_DMA
	sh: Remove unused HAVE_COPY_THREAD_TLS macro
	locking/lockdep: Cure noinstr fail
	ASoC: SOF: Intel: fix page fault at probe if i915 init fails
	octeontx2-af: Fix missing check bugs in rvu_cgx.c
	net: dsa: mv88e6xxx: also read STU state in mv88e6250_g1_vtu_getnext
	selftests/powerpc: Fix exit status of pkey tests
	sh_eth: Fix power down vs. is_opened flag ordering
	nvme-pci: refactor nvme_unmap_data
	nvme-pci: fix error unwind in nvme_map_data
	cachefiles: Drop superfluous readpages aops NULL check
	lightnvm: fix memory leak when submit fails
	skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too
	kasan: fix unaligned address is unhandled in kasan_remove_zero_shadow
	kasan: fix incorrect arguments passing in kasan_add_zero_shadow
	tcp: fix TCP socket rehash stats mis-accounting
	net_sched: gen_estimator: support large ewma log
	udp: mask TOS bits in udp_v4_early_demux()
	ipv6: create multicast route with RTPROT_KERNEL
	net_sched: avoid shift-out-of-bounds in tcindex_set_parms()
	net_sched: reject silly cell_log in qdisc_get_rtab()
	ipv6: set multicast flag on the multicast route
	net: mscc: ocelot: allow offloading of bridge on top of LAG
	net: Disable NETIF_F_HW_TLS_RX when RXCSUM is disabled
	net: dsa: b53: fix an off by one in checking "vlan->vid"
	tcp: do not mess with cloned skbs in tcp_add_backlog()
	tcp: fix TCP_USER_TIMEOUT with zero window
	net: mscc: ocelot: Fix multicast to the CPU port
	net: core: devlink: use right genl user_ptr when handling port param get/set
	pinctrl: qcom: Allow SoCs to specify a GPIO function that's not 0
	pinctrl: qcom: No need to read-modify-write the interrupt status
	pinctrl: qcom: Properly clear "intr_ack_high" interrupts when unmasking
	pinctrl: qcom: Don't clear pending interrupts when enabling
	x86/sev: Fix nonistr violation
	tty: implement write_iter
	tty: fix up hung_up_tty_write() conversion
	net: systemport: free dev before on error path
	x86/sev-es: Handle string port IO to kernel memory properly
	tcp: Fix potential use-after-free due to double kfree()
	ASoC: SOF: Intel: hda: Avoid checking jack on system suspend
	drm/i915/hdcp: Get conn while content_type changed
	bpf: Local storage helpers should check nullness of owner ptr passed
	kernfs: implement ->read_iter
	kernfs: implement ->write_iter
	kernfs: wire up ->splice_read and ->splice_write
	interconnect: imx8mq: Use icc_sync_state
	fs/pipe: allow sendfile() to pipe again
	Commit 9bb48c82aced ("tty: implement write_iter") converted the tty layer to use write_iter. Fix the redirected_tty_write declaration also in n_tty and change the comparisons to use write_iter instead of write. also in n_tty and change the comparisons to use write_iter instead of write.
	mm: fix initialization of struct page for holes in memory layout
	Revert "mm: fix initialization of struct page for holes in memory layout"
	Linux 5.10.11

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I502239d06f9bcd68b59149376f3c796c64de5942
2021-01-27 12:12:33 +01:00
Shakeel Butt
371f3fbf4f mm: fix numa stats for thp migration
commit 5c447d274f3746fbed6e695e7b9a2d7bd8b31b71 upstream.

Currently the kernel is not correctly updating the numa stats for
NR_FILE_PAGES and NR_SHMEM on THP migration.  Fix that.

For NR_FILE_DIRTY and NR_ZONE_WRITE_PENDING, although at the moment
there is no need to handle THP migration as kernel still does not have
write support for file THP but to be more future proof, this patch adds
the THP support for those stats as well.

Link: https://lkml.kernel.org/r/20210108155813.2914586-2-shakeelb@google.com
Fixes: e71769ae52 ("mm: enable thp migration for shmem thp")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27 11:55:14 +01:00
Shakeel Butt
0dc3a130cc mm: memcg: fix memcg file_dirty numa stat
commit 8a8792f600abacd7e1b9bb667759dca1c153f64c upstream.

The kernel updates the per-node NR_FILE_DIRTY stats on page migration
but not the memcg numa stats.

That was not an issue until recently the commit 5f9a4f4a70 ("mm:
memcontrol: add the missing numa_stat interface for cgroup v2") exposed
numa stats for the memcg.

So fix the file_dirty per-memcg numa stat.

Link: https://lkml.kernel.org/r/20210108155813.2914586-1-shakeelb@google.com
Fixes: 5f9a4f4a70 ("mm: memcontrol: add the missing numa_stat interface for cgroup v2")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27 11:55:14 +01:00
Laurent Dufour
320b684750 FROMLIST: mm/migrate: Pass vm_fault pointer to migrate_misplaced_page()
migrate_misplaced_page() is only called during the page fault handling so
it's better to pass the pointer to the struct vm_fault instead of the vma.

This way during the speculative page fault path the saved vma->vm_flags
could be used.

Change-Id: I254a7c9d91dca9ee8a9afd5eccd6de9af5dc8bc0
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Link: https://lore.kernel.org/lkml/1523975611-15978-14-git-send-email-ldufour@linux.vnet.ibm.com/
Bug: 161210518
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
2021-01-22 18:00:23 +00:00
Laurent Dufour
32507b6ff2 FROMLIST: mm: cache some VMA fields in the vm_fault structure
When handling speculative page fault, the vma->vm_flags and
vma->vm_page_prot fields are read once the page table lock is released. So
there is no more guarantee that these fields would not change in our back.
They will be saved in the vm_fault structure before the VMA is checked for
changes.

This patch also set the fields in hugetlb_no_page() and
__collapse_huge_page_swapin even if it is not need for the callee.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Change-Id: I9821f02ea32ef220b57b8bfd817992bbf71bbb1d
Link: https://lore.kernel.org/lkml/1523975611-15978-13-git-send-email-ldufour@linux.vnet.ibm.com/
Bug: 161210518
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
2021-01-22 18:00:15 +00:00
Shakeel Butt
dd156e3fca mm/rmap: always do TTU_IGNORE_ACCESS
[ Upstream commit 013339df116c2ee0d796dd8bfb8f293a2030c063 ]

Since commit 369ea8242c ("mm/rmap: update to new mmu_notifier semantic
v2"), the code to check the secondary MMU's page table access bit is
broken for !(TTU_IGNORE_ACCESS) because the page is unmapped from the
secondary MMU's page table before the check.  More specifically for those
secondary MMUs which unmap the memory in
mmu_notifier_invalidate_range_start() like kvm.

However memory reclaim is the only user of !(TTU_IGNORE_ACCESS) or the
absence of TTU_IGNORE_ACCESS and it explicitly performs the page table
access check before trying to unmap the page.  So, at worst the reclaim
will miss accesses in a very short window if we remove page table access
check in unmapping code.

There is an unintented consequence of !(TTU_IGNORE_ACCESS) for the memcg
reclaim.  From memcg reclaim the page_referenced() only account the
accesses from the processes which are in the same memcg of the target page
but the unmapping code is considering accesses from all the processes, so,
decreasing the effectiveness of memcg reclaim.

The simplest solution is to always assume TTU_IGNORE_ACCESS in unmapping
code.

Link: https://lkml.kernel.org/r/20201104231928.1494083-1-shakeelb@google.com
Fixes: 369ea8242c ("mm/rmap: update to new mmu_notifier semantic v2")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:55 +01:00
Mike Kravetz
336bf30eb7 hugetlbfs: fix anon huge page migration race
Qian Cai reported the following BUG in [1]

  LTP: starting move_pages12
  BUG: unable to handle page fault for address: ffffffffffffffe0
  ...
  RIP: 0010:anon_vma_interval_tree_iter_first+0xa2/0x170 avc_start_pgoff at mm/interval_tree.c:63
  Call Trace:
    rmap_walk_anon+0x141/0xa30 rmap_walk_anon at mm/rmap.c:1864
    try_to_unmap+0x209/0x2d0 try_to_unmap at mm/rmap.c:1763
    migrate_pages+0x1005/0x1fb0
    move_pages_and_store_status.isra.47+0xd7/0x1a0
    __x64_sys_move_pages+0xa5c/0x1100
    do_syscall_64+0x5f/0x310
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

Hugh Dickins diagnosed this as a migration bug caused by code introduced
to use i_mmap_rwsem for pmd sharing synchronization.  Specifically, the
routine unmap_and_move_huge_page() is always passing the TTU_RMAP_LOCKED
flag to try_to_unmap() while holding i_mmap_rwsem.  This is wrong for
anon pages as the anon_vma_lock should be held in this case.  Further
analysis suggested that i_mmap_rwsem was not required to he held at all
when calling try_to_unmap for anon pages as an anon page could never be
part of a shared pmd mapping.

Discussion also revealed that the hack in hugetlb_page_mapping_lock_write
to drop page lock and acquire i_mmap_rwsem is wrong.  There is no way to
keep mapping valid while dropping page lock.

This patch does the following:

 - Do not take i_mmap_rwsem and set TTU_RMAP_LOCKED for anon pages when
   calling try_to_unmap.

 - Remove the hacky code in hugetlb_page_mapping_lock_write. The routine
   will now simply do a 'trylock' while still holding the page lock. If
   the trylock fails, it will return NULL. This could impact the
   callers:

    - migration calling code will receive -EAGAIN and retry up to the
      hard coded limit (10).

    - memory error code will treat the page as BUSY. This will force
      killing (SIGKILL) instead of SIGBUS any mapping tasks.

   Do note that this change in behavior only happens when there is a
   race. None of the standard kernel testing suites actually hit this
   race, but it is possible.

[1] https://lore.kernel.org/lkml/20200708012044.GC992@lca.pw/
[2] https://lore.kernel.org/linux-mm/alpine.LSU.2.11.2010071833100.2214@eggly.anvils/

Fixes: c0d0381ade ("hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization")
Reported-by: Qian Cai <cai@lca.pw>
Suggested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20201105195058.78401-1-mike.kravetz@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-14 11:26:04 -08:00
Miaohe Lin
4dc200cee1 mm/migrate: avoid possible unnecessary process right check in kernel_move_pages()
There is no need to check if this process has the right to modify the
specified process when they are same.  And we could also skip the security
hook call if a process is modifying its own pages.  Add helper function to
handle these.

Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Hongxiang Lou <louhongxiang@huawei.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christopher Lameter <cl@linux.com>
Link: https://lkml.kernel.org/r/20200819083331.19012-1-linmiaohe@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-18 09:27:09 -07:00
Oscar Salvador
79f5f8fab4 mm,hwpoison: rework soft offline for in-use pages
This patch changes the way we set and handle in-use poisoned pages.  Until
now, poisoned pages were released to the buddy allocator, trusting that
the checks that take place at allocation time would act as a safe net and
would skip that page.

This has proved to be wrong, as we got some pfn walkers out there, like
compaction, that all they care is the page to be in a buddy freelist.

Although this might not be the only user, having poisoned pages in the
buddy allocator seems a bad idea as we should only have free pages that
are ready and meant to be used as such.

Before explaining the taken approach, let us break down the kind of pages
we can soft offline.

- Anonymous THP (after the split, they end up being 4K pages)
- Hugetlb
- Order-0 pages (that can be either migrated or invalited)

* Normal pages (order-0 and anon-THP)

  - If they are clean and unmapped page cache pages, we invalidate
    then by means of invalidate_inode_page().
  - If they are mapped/dirty, we do the isolate-and-migrate dance.

Either way, do not call put_page directly from those paths.  Instead, we
keep the page and send it to page_handle_poison to perform the right
handling.

page_handle_poison sets the HWPoison flag and does the last put_page.

Down the chain, we placed a check for HWPoison page in
free_pages_prepare, that just skips any poisoned page, so those pages
do not end up in any pcplist/freelist.

After that, we set the refcount on the page to 1 and we increment
the poisoned pages counter.

If we see that the check in free_pages_prepare creates trouble, we can
always do what we do for free pages:

  - wait until the page hits buddy's freelists
  - take it off, and flag it

The downside of the above approach is that we could race with an
allocation, so by the time we  want to take the page off the buddy, the
page has been already allocated so we cannot soft offline it.
But the user could always retry it.

* Hugetlb pages

  - We isolate-and-migrate them

After the migration has been successful, we call dissolve_free_huge_page,
and we set HWPoison on the page if we succeed.
Hugetlb has a slightly different handling though.

While for non-hugetlb pages we cared about closing the race with an
allocation, doing so for hugetlb pages requires quite some additional
and intrusive code (we would need to hook in free_huge_page and some other
places).
So I decided to not make the code overly complicated and just fail
normally if the page we allocated in the meantime.

We can always build on top of this.

As a bonus, because of the way we handle now in-use pages, we no longer
need the put-as-isolation-migratetype dance, that was guarding for poisoned
pages to end up in pcplists.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Aristeu Rozanski <aris@ruivo.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitry Yakunin <zeil@yandex-team.ru>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200922135650.1634-10-osalvador@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 11:11:16 -07:00
Ralph Campbell
f1f4f3ab54 mm/migrate: remove obsolete comment about device public
Device public memory never had an in tree consumer and was removed in
commit 25b2995a35 ("mm: remove MEMORY_DEVICE_PUBLIC support").  Delete
the obsolete comment.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20200827190735.12752-2-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:36 -07:00
Ralph Campbell
4257889124 mm/migrate: remove cpages-- in migrate_vma_finalize()
The variable struct migrate_vma->cpages is only used in
migrate_vma_setup().  There is no need to decrement it in
migrate_vma_finalize() since it is never checked.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20200827190735.12752-1-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:35 -07:00
Linus Torvalds
3ad11d7ac8 Merge tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:

 - Series of merge handling cleanups (Baolin, Christoph)

 - Series of blk-throttle fixes and cleanups (Baolin)

 - Series cleaning up BDI, seperating the block device from the
   backing_dev_info (Christoph)

 - Removal of bdget() as a generic API (Christoph)

 - Removal of blkdev_get() as a generic API (Christoph)

 - Cleanup of is-partition checks (Christoph)

 - Series reworking disk revalidation (Christoph)

 - Series cleaning up bio flags (Christoph)

 - bio crypt fixes (Eric)

 - IO stats inflight tweak (Gabriel)

 - blk-mq tags fixes (Hannes)

 - Buffer invalidation fixes (Jan)

 - Allow soft limits for zone append (Johannes)

 - Shared tag set improvements (John, Kashyap)

 - Allow IOPRIO_CLASS_RT for CAP_SYS_NICE (Khazhismel)

 - DM no-wait support (Mike, Konstantin)

 - Request allocation improvements (Ming)

 - Allow md/dm/bcache to use IO stat helpers (Song)

 - Series improving blk-iocost (Tejun)

 - Various cleanups (Geert, Damien, Danny, Julia, Tetsuo, Tian, Wang,
   Xianting, Yang, Yufen, yangerkun)

* tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block: (191 commits)
  block: fix uapi blkzoned.h comments
  blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue
  blk-mq: get rid of the dead flush handle code path
  block: get rid of unnecessary local variable
  block: fix comment and add lockdep assert
  blk-mq: use helper function to test hw stopped
  block: use helper function to test queue register
  block: remove redundant mq check
  block: invoke blk_mq_exit_sched no matter whether have .exit_sched
  percpu_ref: don't refer to ref->data if it isn't allocated
  block: ratelimit handle_bad_sector() message
  blk-throttle: Re-use the throtl_set_slice_end()
  blk-throttle: Open code __throtl_de/enqueue_tg()
  blk-throttle: Move service tree validation out of the throtl_rb_first()
  blk-throttle: Move the list operation after list validation
  blk-throttle: Fix IO hang for a corner case
  blk-throttle: Avoid tracking latency if low limit is invalid
  blk-throttle: Avoid getting the current time if tg->last_finish_time is 0
  blk-throttle: Remove a meaningless parameter for throtl_downgrade_state()
  block: Remove redundant 'return' statement
  ...
2020-10-13 12:12:44 -07:00
Zi Yan
6c5c7b9f33 mm/migrate: correct thp migration stats
PageTransHuge returns true for both thp and hugetlb, so thp stats was
counting both thp and hugetlb migrations.  Exclude hugetlb migration by
setting is_thp variable right.

Clean up thp handling code too when we are there.

Fixes: 1a5bae25e3 ("mm/vmstat: add events for THP migration without split")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lkml.kernel.org/r/20200917210413.1462975-1-zi.yan@sent.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-26 10:33:57 -07:00
Christoph Hellwig
f56753ac2a bdi: replace BDI_CAP_NO_{WRITEBACK,ACCT_DIRTY} with a single flag
Replace the two negative flags that are always used together with a
single positive flag that indicates the writeback capability instead
of two related non-capabilities.  Also remove the pointless wrappers
to just check the flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24 13:43:39 -06:00
Hugh Dickins
a333e3e73b mm: migration of hugetlbfs page skip memcg
hugetlbfs pages do not participate in memcg: so although they do find most
of migrate_page_states() useful, it would be better if they did not call
into mem_cgroup_migrate() - where Qian Cai reported that LTP's
move_pages12 triggers the warning in Alex Shi's prospective commit
"mm/memcg: warning on !memcg after readahead page charged".

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxch.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301359460.5954@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-19 13:13:38 -07:00
Ralph Campbell
3d321bf82c mm/migrate: preserve soft dirty in remove_migration_pte()
The code to remove a migration PTE and replace it with a device private
PTE was not copying the soft dirty bit from the migration entry.  This
could lead to page contents not being marked dirty when faulting the page
back from device private memory.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Link: https://lkml.kernel.org/r/20200831212222.22409-3-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-05 12:14:30 -07:00
Ralph Campbell
6128763fc3 mm/migrate: remove unnecessary is_zone_device_page() check
Patch series "mm/migrate: preserve soft dirty in remove_migration_pte()".

I happened to notice this from code inspection after seeing Alistair
Popple's patch ("mm/rmap: Fixup copying of soft dirty and uffd ptes").

This patch (of 2):

The check for is_zone_device_page() and is_device_private_page() is
unnecessary since the latter is sufficient to determine if the page is a
device private page.  Simplify the code for easier reading.

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Link: https://lkml.kernel.org/r/20200831212222.22409-1-rcampbell@nvidia.com
Link: https://lkml.kernel.org/r/20200831212222.22409-2-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-05 12:14:30 -07:00
Alistair Popple
ad7df764b7 mm/rmap: fixup copying of soft dirty and uffd ptes
During memory migration a pte is temporarily replaced with a migration
swap pte.  Some pte bits from the existing mapping such as the soft-dirty
and uffd write-protect bits are preserved by copying these to the
temporary migration swap pte.

However these bits are not stored at the same location for swap and
non-swap ptes.  Therefore testing these bits requires using the
appropriate helper function for the given pte type.

Unfortunately several code locations were found where the wrong helper
function is being used to test soft_dirty and uffd_wp bits which leads to
them getting incorrectly set or cleared during page-migration.

Fix these by using the correct tests based on pte type.

Fixes: a5430dda8a ("mm/migrate: support un-addressable ZONE_DEVICE page in migration")
Fixes: 8c3328f1f3 ("mm/migrate: migrate_vma() unmap page from vma while collecting pages")
Fixes: f45ec5ff16 ("userfaultfd: wp: support swap and page migration")
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Alistair Popple <alistair@popple.id.au>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200825064232.10023-2-alistair@popple.id.au
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-05 12:14:30 -07:00
Alistair Popple
ebdf8321ee mm/migrate: fixup setting UFFD_WP flag
Commit f45ec5ff16 ("userfaultfd: wp: support swap and page migration")
introduced support for tracking the uffd wp bit during page migration.
However the non-swap PTE variant was used to set the flag for zone device
private pages which are a type of swap page.

This leads to corruption of the swap offset if the original PTE has the
uffd_wp flag set.

Fixes: f45ec5ff16 ("userfaultfd: wp: support swap and page migration")
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Link: https://lkml.kernel.org/r/20200825064232.10023-1-alistair@popple.id.au
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-05 12:14:30 -07:00
Matthew Wilcox (Oracle)
6c357848b4 mm: replace hpage_nr_pages with thp_nr_pages
The thp prefix is more frequently used than hpage and we should be
consistent between the various functions.

[akpm@linux-foundation.org: fix mm/migrate.c]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: http://lkml.kernel.org/r/20200629151959.15779-6-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 19:56:56 -07:00
Joonsoo Kim
a097631160 mm/mempolicy: use a standard migration target allocation callback
There is a well-defined migration target allocation callback.  Use it.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Link: http://lkml.kernel.org/r/1594622517-20681-7-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Joonsoo Kim
19fc7bed25 mm/migrate: introduce a standard migration target allocation function
There are some similar functions for migration target allocation.  Since
there is no fundamental difference, it's better to keep just one rather
than keeping all variants.  This patch implements base migration target
allocation function.  In the following patches, variants will be converted
to use this function.

Changes should be mechanical, but, unfortunately, there are some
differences.  First, some callers' nodemask is assgined to NULL since NULL
nodemask will be considered as all available nodes, that is,
&node_states[N_MEMORY].  Second, for hugetlb page allocation, gfp_mask is
redefined as regular hugetlb allocation gfp_mask plus __GFP_THISNODE if
user provided gfp_mask has it.  This is because future caller of this
function requires to set this node constaint.  Lastly, if provided nodeid
is NUMA_NO_NODE, nodeid is set up to the node where migration source
lives.  It helps to remove simple wrappers for setting up the nodeid.

Note that PageHighmem() call in previous function is changed to open-code
"is_highmem_idx()" since it provides more readability.

[akpm@linux-foundation.org: tweak patch title, per Vlastimil]
[akpm@linux-foundation.org: fix typo in comment]

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Link: http://lkml.kernel.org/r/1594622517-20681-6-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Joonsoo Kim
9933a0c8a5 mm/migrate: clear __GFP_RECLAIM to make the migration callback consistent with regular THP allocations
new_page_nodemask is a migration callback and it tries to use a common gfp
flags for the target page allocation whether it is a base page or a THP.
The later only adds GFP_TRANSHUGE to the given mask.  This results in the
allocation being slightly more aggressive than necessary because the
resulting gfp mask will contain also __GFP_RECLAIM_KSWAPD.  THP
allocations usually exclude this flag to reduce over eager background
reclaim during a high THP allocation load which has been seen during large
mmaps initialization.  There is no indication that this is a problem for
migration as well but theoretically the same might happen when migrating
large mappings to a different node.  Make the migration callback
consistent with regular THP allocations.

[akpm@linux-foundation.org: fix comment typo, per Vlastimil]

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Link: http://lkml.kernel.org/r/1594622517-20681-5-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Joonsoo Kim
d92bbc2719 mm/hugetlb: unify migration callbacks
There is no difference between two migration callback functions,
alloc_huge_page_node() and alloc_huge_page_nodemask(), except
__GFP_THISNODE handling.  It's redundant to have two almost similar
functions in order to handle this flag.  So, this patch tries to remove
one by introducing a new argument, gfp_mask, to
alloc_huge_page_nodemask().

After introducing gfp_mask argument, it's caller's job to provide correct
gfp_mask.  So, every callsites for alloc_huge_page_nodemask() are changed
to provide gfp_mask.

Note that it's safe to remove a node id check in alloc_huge_page_node()
since there is no caller passing NUMA_NO_NODE as a node id.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Link: http://lkml.kernel.org/r/1594622517-20681-4-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Joonsoo Kim
b4b382238e mm/migrate: move migration helper from .h to .c
It's not performance sensitive function.  Move it to .c.  This is a
preparation step for future change.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Link: http://lkml.kernel.org/r/1594622517-20681-3-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Randy Dunlap
eaf444deed mm/migrate.c: delete duplicated word
Drop the repeated word "and".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200801173822.14973-8-rdunlap@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:58 -07:00
Anshuman Khandual
1a5bae25e3 mm/vmstat: add events for THP migration without split
Add following new vmstat events which will help in validating THP
migration without split.  Statistics reported through these new VM events
will help in performance debugging.

1. THP_MIGRATION_SUCCESS
2. THP_MIGRATION_FAILURE
3. THP_MIGRATION_SPLIT

In addition, these new events also update normal page migration statistics
appropriately via PGMIGRATE_SUCCESS and PGMIGRATE_FAILURE.  While here,
this updates current trace event 'mm_migrate_pages' to accommodate now
available THP statistics.

[akpm@linux-foundation.org: s/hpage_nr_pages/thp_nr_pages/]
[ziy@nvidia.com: v2]
  Link: http://lkml.kernel.org/r/C5E3C65C-8253-4638-9D3C-71A61858BB8B@nvidia.com
[anshuman.khandual@arm.com: s/thp_nr_pages/hpage_nr_pages/]
  Link: http://lkml.kernel.org/r/1594287583-16568-1-git-send-email-anshuman.khandual@arm.com

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Link: http://lkml.kernel.org/r/1594080415-27924-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:57 -07:00
Ralph Campbell
0744f2807a mm/migrate: optimize migrate_vma_setup() for holes
Patch series "mm/migrate: optimize migrate_vma_setup() for holes".

A simple optimization for migrate_vma_*() when the source vma is not an
anonymous vma and a new test case to exercise it.

This patch (of 2):

When migrating system memory to device private memory, if the source
address range is a valid VMA range and there is no memory or a zero page,
the source PFN array is marked as valid but with no PFN.

This lets the device driver allocate private memory and clear it, then
insert the new device private struct page into the CPU's page tables when
migrate_vma_pages() is called.  migrate_vma_pages() only inserts the new
page if the VMA is an anonymous range.

There is no point in telling the device driver to allocate device private
memory and then not migrate the page.  Instead, mark the source PFN array
entries as not migrating to avoid this overhead.

[rcampbell@nvidia.com: v2]
  Link: http://lkml.kernel.org/r/20200710194840.7602-2-rcampbell@nvidia.com

Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: "Bharata B Rao" <bharata@linux.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/20200710194840.7602-1-rcampbell@nvidia.com
Link: http://lkml.kernel.org/r/20200709165711.26584-1-rcampbell@nvidia.com
Link: http://lkml.kernel.org/r/20200709165711.26584-2-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:56 -07:00
Joonsoo Kim
b518154e59 mm/vmscan: protect the workingset on anonymous LRU
In current implementation, newly created or swap-in anonymous page is
started on active list.  Growing active list results in rebalancing
active/inactive list so old pages on active list are demoted to inactive
list.  Hence, the page on active list isn't protected at all.

Following is an example of this situation.

Assume that 50 hot pages on active list.  Numbers denote the number of
pages on active/inactive list (active | inactive).

1. 50 hot pages on active list
50(h) | 0

2. workload: 50 newly created (used-once) pages
50(uo) | 50(h)

3. workload: another 50 newly created (used-once) pages
50(uo) | 50(uo), swap-out 50(h)

This patch tries to fix this issue.  Like as file LRU, newly created or
swap-in anonymous pages will be inserted to the inactive list.  They are
promoted to active list if enough reference happens.  This simple
modification changes the above example as following.

1. 50 hot pages on active list
50(h) | 0

2. workload: 50 newly created (used-once) pages
50(h) | 50(uo)

3. workload: another 50 newly created (used-once) pages
50(h) | 50(uo), swap-out 50(uo)

As you can see, hot pages on active list would be protected.

Note that, this implementation has a drawback that the page cannot be
promoted and will be swapped-out if re-access interval is greater than the
size of inactive list but less than the size of total(active+inactive).
To solve this potential issue, following patch will apply workingset
detection similar to the one that's already applied to file LRU.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Link: http://lkml.kernel.org/r/1595490560-15117-3-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:55 -07:00
Ralph Campbell
c1a06df6eb mm/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER
On x86_64, when CONFIG_MMU_NOTIFIER is not set/enabled, there is a
compiler error:

   mm/migrate.c: In function 'migrate_vma_collect':
   mm/migrate.c:2481:7: error: 'struct mmu_notifier_range' has no member named 'migrate_pgmap_owner'
     range.migrate_pgmap_owner = migrate->pgmap_owner;
          ^

Fixes: 998427b3ad ("mm/notifier: add migration invalidation type")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "Jason Gunthorpe" <jgg@mellanox.com>
Link: http://lkml.kernel.org/r/20200806193353.7124-1-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:21 -07:00
Linus Torvalds
fffe3ae0ee Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull hmm updates from Jason Gunthorpe:
 "Ralph has been working on nouveau's use of hmm_range_fault() and
  migrate_vma() which resulted in this small series. It adds reporting
  of the page table order from hmm_range_fault() and some optimization
  of migrate_vma():

   - Report the size of the page table mapping out of hmm_range_fault().

     This makes it easier to establish a large/huge/etc mapping in the
     device's page table.

   - Allow devices to ignore the invalidations during migration in cases
     where the migration is not going to change pages.

     For instance migrating pages to a device does not require the
     device to invalidate pages already in the device.

   - Update nouveau and hmm_tests to use the above"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  mm/hmm/test: use the new migration invalidation
  nouveau/svm: use the new migration invalidation
  mm/notifier: add migration invalidation type
  mm/migrate: add a flags parameter to migrate_vma
  nouveau: fix storing invalid ptes
  nouveau/hmm: support mapping large sysmem pages
  nouveau: fix mapping 2MB sysmem pages
  nouveau/hmm: fault one page at a time
  mm/hmm: add tests for hmm_pfn_to_map_order()
  mm/hmm: provide the page mapping order in hmm_range_fault()
2020-08-05 13:28:50 -07:00
Ralph Campbell
998427b3ad mm/notifier: add migration invalidation type
Currently migrate_vma_setup() calls mmu_notifier_invalidate_range_start()
which flushes all device private page mappings whether or not a page is
being migrated to/from device private memory.

In order to not disrupt device mappings that are not being migrated, shift
the responsibility for clearing device private mappings to the device
driver and leave CPU page table unmapping handled by
migrate_vma_setup().

To support this, the caller of migrate_vma_setup() should always set
struct migrate_vma::pgmap_owner to a non NULL value that matches the
device private page->pgmap->owner. This value is then passed to the struct
mmu_notifier_range with a new event type which the driver's invalidation
function can use to avoid device MMU invalidations.

Link: https://lore.kernel.org/r/20200723223004.9586-4-rcampbell@nvidia.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-07-28 16:20:33 -03:00
Ralph Campbell
5143192cd4 mm/migrate: add a flags parameter to migrate_vma
The src_owner field in struct migrate_vma is being used for two purposes,
it acts as a selection filter for which types of pages are to be migrated
and it identifies device private pages owned by the caller.

Split this into separate parameters so the src_owner field can be used
just to identify device private pages owned by the caller of
migrate_vma_setup().

Rename the src_owner field to pgmap_owner to reflect it is now used only
to identify which device private pages to migrate.

Link: https://lore.kernel.org/r/20200723223004.9586-3-rcampbell@nvidia.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-07-28 16:20:33 -03:00
Linus Torvalds
6ec4476ac8 Raise gcc version requirement to 4.9
I realize that we fairly recently raised it to 4.8, but the fact is, 4.9
is a much better minimum version to target.

We have a number of workarounds for actual bugs in pre-4.9 gcc versions
(including things like internal compiler errors on ARM), but we also
have some syntactic workarounds for lacking features.

In particular, raising the minimum to 4.9 means that we can now just
assume _Generic() exists, which is likely the much better replacement
for a lot of very convoluted built-time magic with conditionals on
sizeof and/or __builtin_choose_expr() with same_type() etc.

Using _Generic also means that you will need to have a very recent
version of 'sparse', but thats easy to build yourself, and much less of
a hassle than some old gcc version can be.

The latest (in a long string) of reasons for minimum compiler version
upgrades was commit 5435f73d5c ("efi/x86: Fix build with gcc 4").

Ard points out that RHEL 7 uses gcc-4.8, but the people who stay back on
old RHEL versions persumably also don't build their own kernels anyway.
And maybe they should cross-built or just have a little side affair with
a newer compiler?

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-08 10:48:35 -07:00
Michel Lespinasse
c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
3e4e28c5a8 mmap locking API: convert mmap_sem API comments
Convert comments that reference old mmap_sem APIs to reference
corresponding new mmap locking APIs instead.

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-12-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Johannes Weiner
d9eb1ea2bf mm: memcontrol: delete unused lrucare handling
Swapin faults were the last event to charge pages after they had already
been put on the LRU list.  Now that we charge directly on swapin, the
lrucare portion of the charge code is unused.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Shakeel Butt <shakeelb@google.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-19-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:48 -07:00
Johannes Weiner
9d82c69438 mm: memcontrol: convert anon and file-thp to new mem_cgroup_charge() API
With the page->mapping requirement gone from memcg, we can charge anon and
file-thp pages in one single step, right after they're allocated.

This removes two out of three API calls - especially the tricky commit
step that needed to happen at just the right time between when the page is
"set up" and when it's "published" - somewhat vague and fluid concepts
that varied by page type.  All we need is a freshly allocated page and a
memcg context to charge.

v2: prevent double charges on pre-allocated hugepages in khugepaged

[hannes@cmpxchg.org: Fix crash - *hpage could be ERR_PTR instead of NULL]
  Link: http://lkml.kernel.org/r/20200512215813.GA487759@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/20200508183105.225460-13-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:48 -07:00
Johannes Weiner
be5d0a74c6 mm: memcontrol: switch to native NR_ANON_MAPPED counter
Memcg maintains a private MEMCG_RSS counter.  This divergence from the
generic VM accounting means unnecessary code overhead, and creates a
dependency for memcg that page->mapping is set up at the time of charging,
so that page types can be told apart.

Convert the generic accounting sites to mod_lruvec_page_state and friends
to maintain the per-cgroup vmstat counter of NR_ANON_MAPPED.  We use
lock_page_memcg() to stabilize page->mem_cgroup during rmap changes, the
same way we do for NR_FILE_MAPPED.

With the previous patch removing MEMCG_CACHE and the private NR_SHMEM
counter, this patch finally eliminates the need to have page->mapping set
up at charge time.  However, we need to have page->mem_cgroup set up by
the time rmap runs and does the accounting, so switch the commit and the
rmap callbacks around.

v2: fix temporary accounting bug by switching rmap<->commit (Joonsoo)

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-11-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:47 -07:00
Johannes Weiner
0d1c20722a mm: memcontrol: switch to native NR_FILE_PAGES and NR_SHMEM counters
Memcg maintains private MEMCG_CACHE and NR_SHMEM counters.  This
divergence from the generic VM accounting means unnecessary code overhead,
and creates a dependency for memcg that page->mapping is set up at the
time of charging, so that page types can be told apart.

Convert the generic accounting sites to mod_lruvec_page_state and friends
to maintain the per-cgroup vmstat counters of NR_FILE_PAGES and NR_SHMEM.
The page is already locked in these places, so page->mem_cgroup is stable;
we only need minimal tweaks of two mem_cgroup_migrate() calls to ensure
it's set up in time.

Then replace MEMCG_CACHE with NR_FILE_PAGES and delete the private
NR_SHMEM accounting sites.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-10-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:47 -07:00
Johannes Weiner
3fba69a56e mm: memcontrol: drop @compound parameter from memcg charging API
The memcg charging API carries a boolean @compound parameter that tells
whether the page we're dealing with is a hugepage.
mem_cgroup_commit_charge() has another boolean @lrucare that indicates
whether the page needs LRU locking or not while charging.  The majority of
callsites know those parameters at compile time, which results in a lot of
naked "false, false" argument lists.  This makes for cryptic code and is a
breeding ground for subtle mistakes.

Thankfully, the huge page state can be inferred from the page itself and
doesn't need to be passed along.  This is safe because charging completes
before the page is published and somebody may split it.

Simplify the callsites by removing @compound, and let memcg infer the
state by using hpage_nr_pages() unconditionally.  That function does
PageTransHuge() to identify huge pages, which also helpfully asserts that
nobody passes in tail pages by accident.

The following patches will introduce a new charging API, best not to carry
over unnecessary weight.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-4-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 20:09:47 -07:00
Hugh Dickins
1966391fa5 mm/migrate.c: attach_page_private already does the get_page
Just finished bisecting mmotm, to find why a test which used to take
four minutes now took more than an hour: the __buffer_migrate_page()
cleanup left behind a get_page() which attach_page_private() now does.

Fixes: cd0f371544 ("mm/migrate.c: call detach_page_private to cleanup code")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 15:19:42 -07:00