Michael Stapelberg has reported that for workload with short big spikes of
writes (GCC linker seem to trigger this frequently) the write throughput
is heavily underestimated and tends to steadily sink until it reaches
zero. This has rather bad impact on writeback throttling (causing
stalls). The problem is that writeback throughput estimate gets updated
at most once per 200 ms. One update happens early after we submit pages
for writeback (at that point writeout of only small fraction of pages is
completed and thus observed throughput is tiny). Next update happens only
during the next write spike (updates happen only from inode writeback and
dirty throttling code) and if that is more than 1s after previous spike,
we decide system was idle and just ignore whatever was written until this
moment.
Fix the problem by making sure writeback throughput estimate is also
updated shortly after writeback completes to get reasonable estimate of
throughput for spiky workloads.
[jack@suse.cz: avoid division by 0 in wb_update_dirty_ratelimit()]
Link: https://lore.kernel.org/lkml/20210617095309.3542373-1-stapelberg+linux@google.com
Link: https://lkml.kernel.org/r/20210713104716.22868-3-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Michael Stapelberg <stapelberg+linux@google.com>
Tested-by: Michael Stapelberg <stapelberg+linux@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "writeback: Fix bandwidth estimates", v4.
Fix estimate of writeback throughput when device is not fully busy doing
writeback. Michael Stapelberg has reported that such workload (e.g.
generated by linking) tends to push estimated throughput down to 0 and as
a result writeback on the device is practically stalled.
The first three patches fix the reported issue, the remaining two patches
are unrelated cleanups of problems I've noticed when reading the code.
This patch (of 4):
Track number of inodes under writeback for each bdi_writeback structure.
We will use this to decide whether wb does any IO and so we can estimate
its writeback throughput. In principle we could use number of pages under
writeback (WB_WRITEBACK counter) for this however normal percpu counter
reads are too inaccurate for our purposes and summing the counter is too
expensive.
Link: https://lkml.kernel.org/r/20210713104519.16394-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20210713104716.22868-1-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Michael Stapelberg <stapelberg+linux@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A recent lockdep report included these lines:
[ 96.177910] 3 locks held by containerd/770:
[ 96.177934] #0: ffff88810815ea28 (&mm->mmap_lock#2){++++}-{3:3},
at: do_user_addr_fault+0x115/0x770
[ 96.177999] #1: ffffffff82915020 (rcu_read_lock){....}-{1:2}, at:
get_swap_device+0x33/0x140
[ 96.178057] #2: ffffffff82955ba0 (fs_reclaim){+.+.}-{0:0}, at:
__fs_reclaim_acquire+0x5/0x30
While it was not useful to that bug report to know where the reclaim lock
had been acquired, it might be useful under other circumstances. Allow
the caller of __fs_reclaim_acquire to specify the instruction pointer to
use.
Link: https://lkml.kernel.org/r/20210719185709.1755149-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In page table entry modifying tests, set_xxx_at() are used to populate
the page table entries. On ARM64, PG_arch_1 (PG_dcache_clean) flag is
set to the target page flag if execution permission is given. The logic
exits since commit 4f04d8f005 ("arm64: MMU definitions"). The page
flag is kept when the page is free'd to buddy's free area list. However,
it will trigger page checking failure when it's pulled from the buddy's
free area list, as the following warning messages indicate.
BUG: Bad page state in process memhog pfn:08000
page:0000000015c0a628 refcount:0 mapcount:0 \
mapping:0000000000000000 index:0x1 pfn:0x8000
flags: 0x7ffff8000000800(arch_1|node=0|zone=0|lastcpupid=0xfffff)
raw: 07ffff8000000800 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag(s) set
This fixes the issue by clearing PG_arch_1 through flush_dcache_page()
after set_xxx_at() is called. For architectures other than ARM64, the
unexpected overhead of cache flushing is acceptable.
Link: https://lkml.kernel.org/r/20210809092631.1888748-13-gshan@redhat.com
Fixes: a5c3b9ffb0 ("mm/debug_vm_pgtable: add tests validating advanced arch page table helpers")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> [powerpc 8xx]
Tested-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> [s390]
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chunyu Hu <chuhu@redhat.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/debug_vm_pgtable: Enhancements", v6.
There are a couple of issues with current implementations and this series
tries to resolve the issues:
(a) All needed information are scattered in variables, passed to various
test functions. The code is organized in pretty much relaxed fashion.
(b) The page isn't allocated from buddy during page table entry modifying
tests. The page can be invalid, conflicting to the implementations
of set_xxx_at() on ARM64. The target page is accessed so that the
iCache can be flushed when execution permission is given on ARM64.
Besides, the target page can be unmapped and accessing to it causes
kernel crash.
"struct pgtable_debug_args" is introduced to address issue (a). For issue
(b), the used page is allocated from buddy in page table entry modifying
tests. The corresponding tets will be skipped if we fail to allocate the
(huge) page. For other test cases, the original page around to kernel
symbol (@start_kernel) is still used.
The patches are organized as below. PATCH[2-10] could be combined to one
patch, but it will make the review harder:
PATCH[1] introduces "struct pgtable_debug_args" as place holder of all
needed information. With it, the old and new implementation
can coexist.
PATCH[2-10] uses "struct pgtable_debug_args" in various test functions.
PATCH[11] removes the unused code for old implementation.
PATCH[12] fixes the issue of corrupted page flag for ARM64
This patch (of 6):
In debug_vm_pgtable(), there are many local variables introduced to track
the needed information and they are passed to the functions for various
test cases. It'd better to introduce a struct as place holder for these
information. With it, what the tests functions need is the struct. In
this way, the code is simplified and easier to be maintained.
Besides, set_xxx_at() could access the data on the corresponding pages in
the page table modifying tests. So the accessed pages in the tests should
have been allocated from buddy. Otherwise, we're accessing pages that
aren't owned by us. This causes issues like page flag corruption or
kernel crash on accessing unmapped page when CONFIG_DEBUG_PAGEALLOC is
enabled.
This introduces "struct pgtable_debug_args". The struct is initialized
and destroyed, but the information in the struct isn't used yet. It will
be used in subsequent patches.
Link: https://lkml.kernel.org/r/20210809092631.1888748-1-gshan@redhat.com
Link: https://lkml.kernel.org/r/20210809092631.1888748-2-gshan@redhat.com
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> [powerpc 8xx]
Tested-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> [s390]
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Usually, ocfs2_downconvert_lock() function always downconverts dlm lock to
the expected level for satisfy dlm bast requests from the other nodes.
But there is a rare situation. When dlm lock conversion is being
canceled, ocfs2_downconvert_lock() function will return -EBUSY. You need
to be aware that ocfs2_cancel_convert() function is asynchronous in fsdlm
implementation.
If we does not requeue this lockres entry, ocfs2 downconvert thread no
longer handles this dlm lock bast request. Then, the other nodes will not
get the dlm lock again, the current node's process will be blocked when
acquire this dlm lock again.
Link: https://lkml.kernel.org/r/20210830044621.12544-1-ghe@suse.com
Signed-off-by: Gang He <ghe@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull clk fix from Stephen Boyd:
"One hotfix for a NULL pointer deref in the Renesas usb clk driver"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: renesas: rcar-usb2-clock-sel: Fix kernel NULL pointer dereference
Pull scheduler fixes from Borislav Petkov:
- Have get_push_task() check whether current has migration disabled and
thus avoid useless invocations of the migration thread
- Rework initialization flow so that all rq->core's are initialized,
even of CPUs which have not been onlined yet, so that iterating over
them all works as expected
* tag 'sched_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix get_push_task() vs migrate_disable()
sched: Fix Core-wide rq->lock for uninitialized CPUs
Pull irq fix from Borislav Petkov:
- Have msix_mask_all() check a global control which says whether MSI-X
masking should be done and thus make it usable on Xen-PV too
* tag 'irq_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
PCI/MSI: Skip masking MSI-X on Xen PV
Pull perf fixes from Borislav Petkov:
- Prevent the amd/power module from being removed while in use
- Mark AMD IBS as not supporting content exclusion
- Add a workaround for AMD erratum #1197 where IBS registers might not
be restored properly after exiting CC6 state
- Fix a potential truncation of a 32-bit variable due to shifting
- Read the correct bits describing the number of configurable address
ranges on Intel PT
* tag 'perf_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/power: Assign pmu.module
perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS Op
perf/x86/amd/ibs: Work around erratum #1197
perf/x86/intel/uncore: Fix integer overflow on 23 bit left shift of a u32
perf/x86/intel/pt: Fix mask of num_address_ranges
Pull x86 fixes from Borislav Petkov:
- Fix build error on RHEL where -Werror=maybe-uninitialized is set.
- Restore the firmware's IDT when calling EFI boot services and before
ExitBootServices() has been called. This fixes a boot failure on what
appears to be a tablet with 32-bit UEFI running a 64-bit kernel.
* tag 'x86_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/resctrl: Fix a maybe-uninitialized build warning treated as error
x86/efi: Restore Firmware IDT before calling ExitBootServices()
The probe was manually passing NULL instead of dev to devm_clk_hw_register.
This caused a Unable to handle kernel NULL pointer dereference error.
Fix this by passing 'dev'.
Signed-off-by: Adam Ford <aford173@gmail.com>
Fixes: a20a40a8bb ("clk: renesas: rcar-usb2-clock-sel: Fix error handling in .probe()")
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull SCSI fix from James Bottomley:
"A single fix for a race introduced by a fix that went into 5.14-rc5"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: core: Fix hang of freezing queue between blocking and running device
Pull USB fixes from Greg KH:
"Here are a few tiny USB fixes for reported issues with some USB
drivers.
These fixes include:
- gadget driver fixes for regressions
- tcpm driver fix
- dwc3 driver fixes
- xhci renesas firmware loading fix, again.
- usb serial option driver device id addition
- usb serial ch341 revert for regression
All all of these have been in linux-next with no reported problems"
* tag 'usb-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: gadget: u_audio: fix race condition on endpoint stop
usb: gadget: f_uac2: fixup feedback endpoint stop
usb: typec: tcpm: Raise vdm_sm_running flag only when VDM SM is running
usb: renesas-xhci: Prefer firmware loading on unknown ROM state
usb: dwc3: gadget: Stop EP0 transfers during pullup disable
usb: dwc3: gadget: Fix dwc3_calc_trbs_left()
Revert "USB: serial: ch341: fix character loss at high transfer rates"
USB: serial: option: add new VID/PID to support Fibocom FG150
Pull powerpc fixes from Michael Ellerman:
- Fix scv implicit soft-mask table for relocated (eg. kdump) kernels
- Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK, which was disabled due to a
typo
Thanks to Lukas Bulwahn, Nicholas Piggin, and Daniel Axtens.
* tag 'powerpc-5.14-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: Fix scv implicit soft-mask table for relocated kernels
powerpc: Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK
Pull block fixes from Jens Axboe:
- Revert the mq-deadline priority handling, it's causing serious
performance regressions. While experimental patches exists to fix
this up, it's too late to do so now. Revert it and re-do it properly
for 5.15 instead.
- Fix a NULL vs IS_ERR() regression in this release (Dan)
- Fix a mq-deadline accounting regression in this release (Bart)
- Mark cryptoloop as deprecated. It's broken and dm-crypt fully
supports it, and it's actively intefering with loop. Plan on removal
for 5.16 (Christoph)
* tag 'block-5.14-2021-08-27' of git://git.kernel.dk/linux-block:
cryptoloop: add a deprecation warning
pd: fix a NULL vs IS_ERR() check
Revert "block/mq-deadline: Prioritize high-priority requests"
mq-deadline: Fix request accounting
Pull ARM SoC fixes from Arnd Bergmann:
"Just two trivial fixes from the reset driver tree, nothing else came
up since the last soc fixes"
* tag 'soc-fixes-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
reset: reset-zynqmp: Fixed the argument data type
reset: RESET_MCHP_SPARX5 should depend on ARCH_SPARX5
Pull ACPI fix from Rafael Wysocki:
"Fix a regression introduced during this cycle that has been partially
addressed by an earlier commit (Andy Shevchenko)"
* tag 'acpi-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
media: ipu3-cio2: Drop reference on error path in cio2_bridge_connect_sensor()
Pull power management fixes from Rafael Wysocki:
"These fix two issues introduced during this cycle, one of which is a
regression and the other one affects new code.
Specifics:
- Prevent the operating performance points (OPP) code from crashing
when some entries in the table of required OPPs are set to error
pointer values (Marijn Suijten)
- Prevent the generic power domains (genpd) framework from
incorrectly overriding the performance state of a device set by its
driver while it is runtime-suspended or when runtime PM of it is
disabled (Dmitry Osipenko)"
* tag 'pm-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: domains: Improve runtime PM performance state handling
opp: core: Check for pending links before reading required_opp pointers
Pull RISC-V fixes from Palmer Dabbelt:
- device tree updates for the Microsemi Polarfire development kit that
fix some mismatches between the u-boot and Linux enternet entries
- ensure that the F register state is correctly reflected in core dumps
* tag 'riscv-for-linus-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: dts: microchip: Add ethernet0 to the aliases node
riscv: dts: microchip: Use 'local-mac-address' for emac1
riscv: Ensure the value of FP registers in the core dump file is up to date
Pull MMC host fix from Ulf Hansson:
- sdhci-iproc: Fix clock error for ACPI rpi's
* tag 'mmc-v5.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
Revert "mmc: sdhci-iproc: Set SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN on BCM2711"
Support for cryptoloop has been officially marked broken and deprecated
in favor of dm-crypt (which supports the same broken algorithms if
needed) in Linux 2.6.4 (released in March 2004), and support for it has
been entirely removed from losetup in util-linux 2.23 (released in April
2013). Add a warning and a deprecation schedule.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210827163250.255325-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull ARM fix from Russell King:
"Resolve a Keystone 2 kernel mapping regression"
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 9104/2: Fix Keystone 2 kernel mapping regression
This reverts commit 419dd626e3.
It turned out that the change from the reverted commit breaks the ACPI
based rpi's because it causes the 100Mhz max clock to be overridden to the
return from sdhci_iproc_get_max_clock(), which is 0 because there isn't a
OF/DT based clock device.
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Fixes: 419dd626e3 ("mmc: sdhci-iproc: Set SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN on BCM2711")
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
When the uac2 function is stopped, there seems to be an issue reported on
some platforms (Intel Merrifield at least)
BUG: kernel NULL pointer dereference, address: 0000000000000008
...
RIP: 0010:dwc3_gadget_del_and_unmap_request+0x19/0xe0
...
Call Trace:
dwc3_remove_requests.constprop.0+0x12f/0x170
__dwc3_gadget_ep_disable+0x7a/0x160
dwc3_gadget_ep_disable+0x3d/0xd0
usb_ep_disable+0x1c/0x70
u_audio_stop_capture+0x79/0x120 [u_audio]
afunc_set_alt+0x73/0x80 [usb_f_uac2]
composite_setup+0x224/0x1b90 [libcomposite]
The issue happens only when the gadget is using the sync type "async", not
"adaptive". This indicates that problem is coming from the feedback
endpoint, which is only used with async synchronization mode.
The problem is that request is freed regardless of usb_ep_dequeue(), which
ends up badly if the request is not actually dequeued yet.
Update the feedback endpoint free function to release the endpoint the same
way it is done for the data endpoint, which takes care of the problem.
Fixes: 24f779dac8 ("usb: gadget: f_uac2/u_audio: add feedback endpoint support")
Reported-by: Ferry Toth <ftoth@exalondelft.nl>
Tested-by: Ferry Toth <ftoth@exalondelft.nl>
Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20210827075853.266912-1-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
