Warning at every leaking bits can cause a flood of message, triggering
various stall-warning mechanisms to fire, including CSD locks, which
makes the machine to be unusable.
Track the bits that are being leaked, and only warn when a new bit is
set.
That said, this patch will help with the following issues:
1) It will tell us which bits are being set, so, it is easy to
communicate it back to vendor, and to do a root-cause analyzes.
2) It avoid the machine to be unusable, because, worst case
scenario, the user gets less than 60 WARNs (one per unhandled bit).
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sandipan Das <sandipan.das@amd.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lkml.kernel.org/r/20241001141020.2620361-1-leitao@debian.org
Add the new helper, xol_get_slot_nr() which does
find_first_zero_bit() + test_and_set_bit().
xol_take_insn_slot() can wait for the "xol_get_slot_nr() < UINSNS_PER_PAGE"
event instead of "area->slot_count < UINSNS_PER_PAGE".
So we can kill area->slot_count and avoid atomic_inc() + atomic_dec(), this
simplifies the code and can slightly improve the performance.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241001142458.GA13629@redhat.com
kernel/events/uprobes.c assumes that xol_area->vaddr is always correct but
a malicious application can remap its "[uprobes]" vma to another adress to
confuse the kernel. Introduce xol_mremap() to make this impossible.
With this change utask->xol_vaddr in xol_free_insn_slot() can't be invalid,
we can turn the offset check into WARN_ON_ONCE(offset >= PAGE_SIZE).
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144258.GA9492@redhat.com
Add the "struct uprobe_task *utask" argument to xol_get_insn_slot() and
xol_free_insn_slot(), their callers already have it so we can avoid the
unnecessary dereference and simplify the code.
Kill the "tsk" argument of xol_free_insn_slot(), it is always current.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144253.GA9487@redhat.com
This simplifies the code and makes xol_get_insn_slot() symmetric with
xol_free_insn_slot() which clears utask->xol_vaddr.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144248.GA9483@redhat.com
The do / while (slot_nr >= UINSNS_PER_PAGE) loop in xol_take_insn_slot()
makes no sense, the checked condition is always true. Change this code
to use the "for (;;)" loop, this way we do not need to change slot_nr if
test_and_set_bit() fails.
Also, kill the unnecessary xol_vaddr != NULL check in xol_get_insn_slot(),
xol_take_insn_slot() never returns NULL.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144244.GA9480@redhat.com
If pre_ssout() succeeds and sets utask->active_uprobe and utask->xol_vaddr
the task must not exit until it calls handle_singlestep() which does the
necessary put_uprobe() and xol_free_insn_slot().
Remove put_uprobe() and xol_free_insn_slot() from uprobe_free_utask(). With
this change xol_free_insn_slot() can't hit xol_area/utask/xol_vaddr == NULL,
we can kill the unnecessary checks checks and simplify this function more.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144239.GA9475@redhat.com
1. Clear utask->xol_vaddr unconditionally, even if this addr is not valid,
xol_free_insn_slot() should never return with utask->xol_vaddr != NULL.
2. Add a comment to explain why do we need to validate slot_addr.
3. Simplify the validation above. We can simply check offset < PAGE_SIZE,
unsigned underflows are fine, it should work if slot_addr < area->vaddr.
4. Kill the unnecessary "slot_nr >= UINSNS_PER_PAGE" check, slot_nr must
be valid if offset < PAGE_SIZE.
The next patches will cleanup this function even more.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144235.GA9471@redhat.com
handle_swbp() calls get_utask() before prepare_uretprobe() or pre_ssout()
can be called, they can simply use current->utask which can't be NULL.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240929144230.GA9468@redhat.com
ArrowLake-H contains 3 different uarchs, LionCove, Skymont and Crestmont.
It is different with previous hybrid processors which only contains two
kinds of uarchs.
This patch adds PMU support for ArrowLake-H processor, adds ARL-H
specific events which supports the 3 kinds of uarchs, such as
td_retiring_arl_h, and extends some existed format attributes like
offcore_rsp to make them be available to support ARL-H as well. Althrough
these format attributes like offcore_rsp have been extended to support
ARL-H, they can still support the regular hybrid platforms with 2 kinds
of uarchs since the helper hybrid_format_is_visible() would filter PMU
types and only show the format attribute for available PMUs.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Link: https://lkml.kernel.org/r/20240820073853.1974746-5-dapeng1.mi@linux.intel.com
The upcoming ARL-H hybrid processor contains 2 different atom uarchs
which have different PMU capabilities. To distinguish these atom uarchs,
CPUID.1AH.EAX[23:0] defines a native model ID which can be used to
uniquely identify the uarch of the core by combining with core type.
Thus a 3rd hybrid pmu type "hybrid_tiny" is defined to mark the 2nd
atom uarch. The helper find_hybrid_pmu_for_cpu() would compare the
hybrid pmu type and dynamically read core native id from cpu to identify
the corresponding hybrid pmu structure.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Link: https://lkml.kernel.org/r/20240820073853.1974746-4-dapeng1.mi@linux.intel.com
Define helper get_this_hybrid_cpu_native_id() to return the CPU core
native ID. This core native ID combining with core type can be used to
figure out the CPU core uarch uniquely.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Link: https://lkml.kernel.org/r/20240820073853.1974746-3-dapeng1.mi@linux.intel.com
Use macros instead of magic number to define hybrid_pmu_type and remove
X86_HYBRID_NUM_PMUS since it's never used.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Link: https://lkml.kernel.org/r/20240820073853.1974746-2-dapeng1.mi@linux.intel.com
bit_wait_io_timeout has been unused since 2016's
commit 6290602709 ("mm: add PageWaiters indicating tasks are waiting for a page bit")
Remove it.
Signed-off-by: "Dr. David Alan Gilbert" <linux@treblig.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lore.kernel.org/r/20241001234016.231696-1-linux@treblig.org
We do not have RESPECT_SLICE, we only have RUN_TO_PARITY.
Change RESPECT_SLICE to RUN_TO_PARITY, makes it more clear.
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
Link: https://lkml.kernel.org/r/20241001070456.10939-1-shijie@os.amperecomputing.com
When PLACE_LAG is enabled, from the relationship:
vl_i = (W + w_i)*vl'_i / W
we know that if vl'_i(se->vlag) is zero, the vl_i is zero too.
So if se->vlag is zero, there is no need to waste cycles to
do the calculation.
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
Link: https://lkml.kernel.org/r/20241001070021.10626-1-shijie@os.amperecomputing.com
The patch "5e963f2bd4 sched/fair: Commit to EEVDF"
removed the code following the DOUBLE_TICK:
-
- if (!sched_feat(EEVDF) && cfs_rq->nr_running > 1)
- check_preempt_tick(cfs_rq, curr);
The DOUBLE_TICK feature becomes dead code now, so remove it.
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: "Christoph Lameter (Ampere)" <cl@linux.com>
Reviewed-by: Vishal Chourasia <vishalc@linux.ibm.com>
Link: https://lore.kernel.org/r/20241001065451.10356-1-shijie@os.amperecomputing.com
__HAVE_THREAD_FUNCTIONS could be defined by architectures wishing to
provide their own task_thread_info(), task_stack_page(),
setup_thread_stack() and end_of_stack() hooks.
Commit cf8e865810 ("arch: Remove Itanium (IA-64) architecture")
removed the last upstream consumer of __HAVE_THREAD_FUNCTIONS, so change
the remaining !CONFIG_THREAD_INFO_IN_TASK && !__HAVE_THREAD_FUNCTIONS
conditionals to only check for the former case.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lkml.kernel.org/r/20240930050945.30304-2-ddiss@suse.de
The waiting in softirq.c is always waiting for a bit to be cleared.
This makes the bit wait functions seem more suitable.
By switching over we can rid of all explicit barriers. We also use
wait_on_bit_lock() to avoid an explicit loop.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-8-neilb@suse.de
It is not currently possible to wait wait_var_event for an io_schedule()
style wait. This patch adds wait_var_event_io() for that purpose.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-7-neilb@suse.de
Sometimes we need to wait for a condition to be true which must be
testing while holding a lock. Correspondingly the condition is made
true while holding the lock and the wake up is sent under the lock.
This patch provides wake and wait interfaces which can be used for this
situation when the lock is a mutex or a spinlock, or any other lock for
which there are foo_lock() and foo_unlock() functions.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-6-neilb@suse.de
There are common patterns in the kernel of using test_and_clear_bit()
before wake_up_bit(), and atomic_dec_and_test() before wake_up_var().
These combinations don't need extra barriers but sometimes include them
unnecessarily.
To help avoid the unnecessary barriers and to help discourage the
general use of wake_up_bit/var (which is a fragile interface) introduce
two combined functions which implement these patterns.
Also add store_release_wake_up() which supports the task of simply
setting a non-atomic variable and sending a wakeup. This pattern
requires barriers which are often omitted.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-5-neilb@suse.de
wake_up_var(), wait_var_event() and related interfaces are not
documented but have important ordering requirements. This patch adds
documentation and makes these requirements explicit.
The return values for those wait_var_event_* functions which return a
value are documented. Note that these are, perhaps surprisingly,
sometimes different from comparable wait_on_bit() functions.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-4-neilb@suse.de
This patch revises the documention for wake_up_bit(),
clear_and_wake_up_bit(), and all the wait_on_bit() family of functions.
The new documentation places less emphasis on the pool of waitqueues
used (an implementation detail) and focuses instead on details of how
the functions behave.
The barriers included in the wait functions and clear_and_wake_up_bit()
and those required for wake_up_bit() are spelled out more clearly.
The error statuses returned are given explicitly.
The fact that the wait_on_bit_lock() function sets the bit is made more
obvious.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-3-neilb@suse.de
wake_up_bit() currently allows a "void *". While this isn't strictly a
problem as the address is never dereferenced, it is inconsistent with
the corresponding wait_on_bit() which requires "unsigned long *" and
does dereference the pointer.
Any code that needs to wait for a change in something other than an
unsigned long would be better served by wake_up_var()/wait_var_event().
This patch changes all related "void *" to "unsigned long *".
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240925053405.3960701-2-neilb@suse.de
If CONFIG_GENERIC_LOCKBREAK=y and CONFIG_DEBUG_LOCK_ALLOC=n
(e.g. sh/sdk7786_defconfig):
kernel/locking/spinlock.c:68:17: warning: no previous prototype for '__raw_spin_lock' [-Wmissing-prototypes]
kernel/locking/spinlock.c:80:26: warning: no previous prototype for '__raw_spin_lock_irqsave' [-Wmissing-prototypes]
kernel/locking/spinlock.c:98:17: warning: no previous prototype for '__raw_spin_lock_irq' [-Wmissing-prototypes]
kernel/locking/spinlock.c:103:17: warning: no previous prototype for '__raw_spin_lock_bh' [-Wmissing-prototypes]
kernel/locking/spinlock.c:68:17: warning: no previous prototype for '__raw_read_lock' [-Wmissing-prototypes]
kernel/locking/spinlock.c:80:26: warning: no previous prototype for '__raw_read_lock_irqsave' [-Wmissing-prototypes]
kernel/locking/spinlock.c:98:17: warning: no previous prototype for '__raw_read_lock_irq' [-Wmissing-prototypes]
kernel/locking/spinlock.c:103:17: warning: no previous prototype for '__raw_read_lock_bh' [-Wmissing-prototypes]
kernel/locking/spinlock.c:68:17: warning: no previous prototype for '__raw_write_lock' [-Wmissing-prototypes]
kernel/locking/spinlock.c:80:26: warning: no previous prototype for '__raw_write_lock_irqsave' [-Wmissing-prototypes]
kernel/locking/spinlock.c:98:17: warning: no previous prototype for '__raw_write_lock_irq' [-Wmissing-prototypes]
kernel/locking/spinlock.c:103:17: warning: no previous prototype for '__raw_write_lock_bh' [-Wmissing-prototypes]
All __raw_* lock ops are internal functions without external callers.
Hence fix this by making them static.
Note that if CONFIG_GENERIC_LOCKBREAK=y, no lock ops are inlined, as all
of CONFIG_INLINE_*_LOCK* depend on !GENERIC_LOCKBREAK.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lkml.kernel.org/r/7201d7fb408375c6c4df541270d787b1b4a32354.1727879348.git.geert+renesas@glider.be
This expands the validation introduced in commit 07bf790895 ("xfrm:
Validate address prefix lengths in the xfrm selector.")
syzbot created an SA with
usersa.sel.family = AF_UNSPEC
usersa.sel.prefixlen_s = 128
usersa.family = AF_INET
Because of the AF_UNSPEC selector, verify_newsa_info doesn't put
limits on prefixlen_{s,d}. But then copy_from_user_state sets
x->sel.family to usersa.family (AF_INET). Do the same conversion in
verify_newsa_info before validating prefixlen_{s,d}, since that's how
prefixlen is going to be used later on.
Reported-by: syzbot+cc39f136925517aed571@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
The Sierra SERDES can be configured for QSGMII and SGMII protocols. Hence,
update the bindings to treat "PHY_TYPE_QSGMII" and "PHY_TYPE_SGMII" as
valid values for the "cdns,phy-type" property.
Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240930095145.3004053-1-s-vadapalli@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Addition of the COMBOPHY driver found on STM32MP25 platforms
This single lane PHY is shared (exclusive) between the USB3 and PCIE
controllers.
Supports 5Gbit/s for PCIE gen2 or 2.5Gbit/s for PCIE gen1.
Supports wakeup-source capability to wakeup system using remote-wakeup
capable USB device
Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
Link: https://lore.kernel.org/r/20240930170847.948779-3-christian.bruel@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Document the bindings for STM32 COMBOPHY interface, used to support
the PCIe and USB3 stm32mp25 drivers.
Following entries can be used to tune caracterisation parameters
- st,output-micro-ohms and st,output-vswing-microvolt bindings entries
to tune the impedance and voltage swing using discrete simulation results
- st,rx-equalizer register to set the internal rx equalizer filter value.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
Link: https://lore.kernel.org/r/20240930170847.948779-2-christian.bruel@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
CP11x UTMI PHY supports swapping D+/D- signals via digital control
register 1.
Add support for the "swap-dx-lanes" device-tree property, which lists
the port-ids that should swap D+ and D-.
The property is evaluated in probe and applied before power-on
during mvebu_cp110_utmi_port_setup.
Signed-off-by: Josua Mayer <josua@solid-run.com>
Link: https://lore.kernel.org/r/20241002-mvebu-utmi-phy-v4-1-83783dc89b9d@solid-run.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Fix the value of SIERRA_DEQ_OPENEYE_CTRL_PREG and add a definition for
SIERRA_DEQ_TAU_EPIOFFSET_MODE_PREG. This fixes the SGMII single link
register configuration.
Fixes: 7a5ad9b4b9 ("phy: cadence: Sierra: Update single link PCIe register configuration")
Signed-off-by: Bartosz Wawrzyniak <bwawrzyn@cisco.com>
Link: https://lore.kernel.org/r/20241003123405.1101157-1-bwawrzyn@cisco.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Return the actual error code upon failure to allocate extcon device, instead
of hardcoding -ENOMEM. Use dev_err_probe() to also log appropriate messages,
which is fine because the containing function is used in the probe path.
Helped-by: Heiko Stubner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
Link: https://lore.kernel.org/r/cc4995aa3e569be6bc23ca126b41fba82d50eeee.1725524802.git.dsimic@manjaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Perform a few trivial code cleanups, e.g. to obey the reverse Christmas tree
rule, to avoid use of "{ ... }" code blocks where they aren't really needed,
or to avoid line wrapping by using the 100-column width better.
No intended functional changes are introduced by these code cleanups.
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
Link: https://lore.kernel.org/r/adce7309f6fd9e1191c53bab552a8531d1a71216.1725524802.git.dsimic@manjaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The Broadcom USB PHY driver contains a lookup table
(`reg_bits_map_tables`) to resolve register bitmaps unique to certain
versions of the USB PHY as found in various Broadcom chip families.
Historically, this table was just kept carefully in sync with the
"selector" enum every time the latter changed to ensure consistency.
However, a recent commit [1] introduced two new enumerators but did not
adjust the array for BCM4908, thus breaking the xHCI controller (and
boot process) on this platform and revealing the fragility of this
approach.
Since these arrays are a little sparse (many elements are zero) and the
position of the array elements is significant only insofar as they agree
with the enumerators, designated initializers are a better fit than
positional initializers here. Convert this table accordingly.
[1] 4536fe9640 ("phy: usb: suppress OC condition for 7439b2")
Signed-off-by: Sam Edwards <CFSworks@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Justin Chen <justin.chen@broadcom.com>
Link: https://lore.kernel.org/r/20241004034131.1363813-3-CFSworks@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The Broadcom USB PHY driver contains a lookup table
(`reg_bits_map_tables`) to resolve register bitmaps unique to certain
versions of the USB PHY as found in various Broadcom chip families. A
recent commit (see 'fixes' tag) introduced two new elements to each chip
family in this table -- except for one: BCM4908. This resulted in the
xHCI controller not being initialized correctly, causing a panic on
boot.
The next patch will update this table to use designated initializers in
order to prevent this from happening again. For now, just add back the
missing array elements to resolve the regression.
Fixes: 4536fe9640 ("phy: usb: suppress OC condition for 7439b2")
Signed-off-by: Sam Edwards <CFSworks@gmail.com>
Reviewed-by: Justin Chen <justin.chen@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20241004034131.1363813-2-CFSworks@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The background blockgc scanner runs on a 5m interval by default and
trims preallocation (post-eof and cow fork) from inodes that are
otherwise idle. Idle effectively means that iolock can be acquired
without blocking and that the inode has no dirty pagecache or I/O in
flight.
This simple mechanism and heuristic has worked fairly well for
post-eof speculative preallocations. Support for reflink and COW
fork preallocations came sometime later and plugged into the same
mechanism, with similar heuristics. Some recent testing has shown
that COW fork preallocation may be notably more sensitive to blockgc
processing than post-eof preallocation, however.
For example, consider an 8GB reflinked file with a COW extent size
hint of 1MB. A worst case fully randomized overwrite of this file
results in ~8k extents of an average size of ~1MB. If the same
workload is interrupted a couple times for blockgc processing
(assuming the file goes idle), the resulting extent count explodes
to over 100k extents with an average size <100kB. This is
significantly worse than ideal and essentially defeats the COW
extent size hint mechanism.
While this particular test is instrumented, it reflects a fairly
reasonable pattern in practice where random I/Os might spread out
over a large period of time with varying periods of (in)activity.
For example, consider a cloned disk image file for a VM or container
with long uptime and variable and bursty usage. A background blockgc
scan that races and processes the image file when it happens to be
clean and idle can have a significant effect on the future
fragmentation level of the file, even when still in use.
To help combat this, update the heuristic to skip cowblocks inodes
that are currently opened for write access during non-sync blockgc
scans. This allows COW fork preallocations to persist for as long as
possible unless otherwise needed for functional purposes (i.e. a
sync scan), the file is idle and closed, or the inode is being
evicted from cache. While here, update the comments to help
distinguish performance oriented heuristics from the logic that
exists to maintain functional correctness.
Suggested-by: Darrick Wong <djwong@kernel.org>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Currently the debug-only xfs_bmap_exact_minlen_extent_alloc allocation
variant fails to drop into the lowmode last resort allocator, and
thus can sometimes fail allocations for which the caller has a
transaction block reservation.
Fix this by using xfs_bmap_btalloc_low_space to do the actual allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_bmap_exact_minlen_extent_alloc duplicates the args setup in
xfs_bmap_btalloc. Switch to call it from xfs_bmap_btalloc after
doing the basic setup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Exact minlen allocations only exist as an error injection tool for debug
builds. Currently this is implemented using ifdefs, which means the code
isn't even compiled for non-XFS_DEBUG builds. Enhance the compile test
coverage by always building the code and use the compilers' dead code
elimination to remove it from the generated binary instead.
The only downside is that the alloc_minlen_only field is unconditionally
added to struct xfs_alloc_args now, but by moving it around and packing
it tightly this doesn't actually increase the size of the structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Userdata and metadata allocations end up in the same allocation helpers.
Remove the separate xfs_bmap_alloc_userdata function to make this more
clear.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Just like xfs_attr3_leaf_split, xfs_attr_node_try_addname can return
-ENOSPC both for an actual failure to allocate a disk block, but also
to signal the caller to convert the format of the attr fork. Use magic
1 to ask for the conversion here as well.
Note that unlike the similar issue in xfs_attr3_leaf_split, this one was
only found by code review.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_attr3_leaf_split propagates the need for an extra btree split as
-ENOSPC to it's only caller, but the same return value can also be
returned from xfs_da_grow_inode when it fails to find free space.
Distinguish the two cases by returning 1 for the extra split case instead
of overloading -ENOSPC.
This can be triggered relatively easily with the pending realtime group
support and a file system with a lot of small zones that use metadata
space on the main device. In this case every about 5-10th run of
xfs/538 runs into the following assert:
ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
in xfs_attr3_leaf_split caused by an allocation failure. Note that
the allocation failure is caused by another bug that will be fixed
subsequently, but this commit at least sorts out the error handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_attr3_leaf_add only has two potential return values, indicating if the
entry could be added or not. Replace the errno return with a bool so that
ENOSPC from it can't easily be confused with a real ENOSPC.
Remove the return value from the xfs_attr3_leaf_add_work helper entirely,
as it always return 0.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_attr_leaf_try_add is only called by xfs_attr_leaf_addname, and
merging the two will simplify a following error handling fix.
To facilitate this move the remote block state save/restore helpers up in
the file so that they don't need forward declarations now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
