Age | Commit message (Collapse) | Author |
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When connected mode is set, and we have connected and datagram traffic in
parallel, ipoib might crash with double free of datagram skb.
The current mechanism assumes that the order in the completion queue is
the same as the order of sent packets for all QPs. Order is kept only for
specific QP, in case of mixed UD and CM traffic we have few QPs (one UD and
few CM's) in parallel.
The problem:
----------------------------------------------------------
Transmit queue:
-----------------
UD skb pointer kept in queue itself, CM skb kept in spearate queue and
uses transmit queue as a placeholder to count the number of total
transmitted packets.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 .........127
------------------------------------------------------------
NL ud1 UD2 CM1 ud3 cm2 cm3 ud4 cm4 ud5 NL NL NL ...........
------------------------------------------------------------
^ ^
tail head
Completion queue (problematic scenario) - the order not the same as in
the transmit queue:
1 2 3 4 5 6 7 8 9
------------------------------------
ud1 CM1 UD2 ud3 cm2 cm3 ud4 cm4 ud5
------------------------------------
1. CM1 'wc' processing
- skb freed in cm separate ring.
- tx_tail of transmit queue increased although UD2 is not freed.
Now driver assumes UD2 index is already freed and it could be used for
new transmitted skb.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 .........127
------------------------------------------------------------
NL NL UD2 CM1 ud3 cm2 cm3 ud4 cm4 ud5 NL NL NL ...........
------------------------------------------------------------
^ ^ ^
(Bad)tail head
(Bad - Could be used for new SKB)
In this case (due to heavy load) UD2 skb pointer could be replaced by new
transmitted packet UD_NEW, as the driver assumes its free. At this point
we will have to process two 'wc' with same index but we have only one
pointer to free.
During second attempt to free the same skb we will have NULL pointer
exception.
2. UD2 'wc' processing
- skb freed according the index we got from 'wc', but it was already
overwritten by mistake. So actually the skb that was released is the
skb of the new transmitted packet and not the original one.
3. UD_NEW 'wc' processing
- attempt to free already freed skb. NUll pointer exception.
The fix:
-----------------------------------------------------------------------
The fix is to stop using the UD ring as a placeholder for CM packets, the
cyclic ring variables tx_head and tx_tail will manage the UD tx_ring, a
new cyclic variables global_tx_head and global_tx_tail are introduced for
managing and counting the overall outstanding sent packets, then the send
queue will be stopped and waken based on these variables only.
Note that no locking is needed since global_tx_head is updated in the xmit
flow and global_tx_tail is updated in the NAPI flow only. A previous
attempt tried to use one variable to count the outstanding sent packets,
but it did not work since xmit and NAPI flows can run at the same time and
the counter will be updated wrongly. Thus, we use the same simple cyclic
head and tail scheme that we have today for the UD tx_ring.
Fixes: 2c104ea68350 ("IB/ipoib: Get rid of the tx_outstanding variable in all modes")
Link: https://lore.kernel.org/r/20200527134705.480068-1-leon@kernel.org
Signed-off-by: Valentine Fatiev <valentinef@mellanox.com>
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
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[Why]
If VUPDATE_END is before VUPDATE_START the delay calculated can become
very large, causing a soft hang.
[How]
Take the absolute value of the difference between START and END.
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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get_cursor_position already handles the case where the cursor has
negative off-screen coordinates by not setting
dc_cursor_position.enabled.
Signed-off-by: Simon Ser <contact@emersion.fr>
Fixes: 626bf90fe03f ("drm/amd/display: add basic atomic check for cursor plane")
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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[Why]
If VUPDATE_END is before VUPDATE_START the delay calculated can become
very large, causing a soft hang.
[How]
Take the absolute value of the difference between START and END.
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
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get_cursor_position already handles the case where the cursor has
negative off-screen coordinates by not setting
dc_cursor_position.enabled.
Signed-off-by: Simon Ser <contact@emersion.fr>
Fixes: 626bf90fe03f ("drm/amd/display: add basic atomic check for cursor plane")
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
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Be there a platform with the following layout:
Regular NIC
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+----> DSA master for switch port
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+----> DSA master for another switch port
After changing DSA back to static lockdep class keys in commit
1a33e10e4a95 ("net: partially revert dynamic lockdep key changes"), this
kernel splat can be seen:
[ 13.361198] ============================================
[ 13.366524] WARNING: possible recursive locking detected
[ 13.371851] 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988 Not tainted
[ 13.377874] --------------------------------------------
[ 13.383201] swapper/0/0 is trying to acquire lock:
[ 13.388004] ffff0000668ff298 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[ 13.397879]
[ 13.397879] but task is already holding lock:
[ 13.403727] ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[ 13.413593]
[ 13.413593] other info that might help us debug this:
[ 13.420140] Possible unsafe locking scenario:
[ 13.420140]
[ 13.426075] CPU0
[ 13.428523] ----
[ 13.430969] lock(&dsa_slave_netdev_xmit_lock_key);
[ 13.435946] lock(&dsa_slave_netdev_xmit_lock_key);
[ 13.440924]
[ 13.440924] *** DEADLOCK ***
[ 13.440924]
[ 13.446860] May be due to missing lock nesting notation
[ 13.446860]
[ 13.453668] 6 locks held by swapper/0/0:
[ 13.457598] #0: ffff800010003de0 ((&idev->mc_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x0/0x400
[ 13.466593] #1: ffffd4d3fb478700 (rcu_read_lock){....}-{1:2}, at: mld_sendpack+0x0/0x560
[ 13.474803] #2: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x64/0xb10
[ 13.483886] #3: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
[ 13.492793] #4: ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[ 13.503094] #5: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
[ 13.512000]
[ 13.512000] stack backtrace:
[ 13.516369] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988
[ 13.530421] Call trace:
[ 13.532871] dump_backtrace+0x0/0x1d8
[ 13.536539] show_stack+0x24/0x30
[ 13.539862] dump_stack+0xe8/0x150
[ 13.543271] __lock_acquire+0x1030/0x1678
[ 13.547290] lock_acquire+0xf8/0x458
[ 13.550873] _raw_spin_lock+0x44/0x58
[ 13.554543] __dev_queue_xmit+0x84c/0xbe0
[ 13.558562] dev_queue_xmit+0x24/0x30
[ 13.562232] dsa_slave_xmit+0xe0/0x128
[ 13.565988] dev_hard_start_xmit+0xf4/0x448
[ 13.570182] __dev_queue_xmit+0x808/0xbe0
[ 13.574200] dev_queue_xmit+0x24/0x30
[ 13.577869] neigh_resolve_output+0x15c/0x220
[ 13.582237] ip6_finish_output2+0x244/0xb10
[ 13.586430] __ip6_finish_output+0x1dc/0x298
[ 13.590709] ip6_output+0x84/0x358
[ 13.594116] mld_sendpack+0x2bc/0x560
[ 13.597786] mld_ifc_timer_expire+0x210/0x390
[ 13.602153] call_timer_fn+0xcc/0x400
[ 13.605822] run_timer_softirq+0x588/0x6e0
[ 13.609927] __do_softirq+0x118/0x590
[ 13.613597] irq_exit+0x13c/0x148
[ 13.616918] __handle_domain_irq+0x6c/0xc0
[ 13.621023] gic_handle_irq+0x6c/0x160
[ 13.624779] el1_irq+0xbc/0x180
[ 13.627927] cpuidle_enter_state+0xb4/0x4d0
[ 13.632120] cpuidle_enter+0x3c/0x50
[ 13.635703] call_cpuidle+0x44/0x78
[ 13.639199] do_idle+0x228/0x2c8
[ 13.642433] cpu_startup_entry+0x2c/0x48
[ 13.646363] rest_init+0x1ac/0x280
[ 13.649773] arch_call_rest_init+0x14/0x1c
[ 13.653878] start_kernel+0x490/0x4bc
Lockdep keys themselves were added in commit ab92d68fc22f ("net: core:
add generic lockdep keys"), and it's very likely that this splat existed
since then, but I have no real way to check, since this stacked platform
wasn't supported by mainline back then.
>From Taehee's own words:
This patch was considered that all stackable devices have LLTX flag.
But the dsa doesn't have LLTX, so this splat happened.
After this patch, dsa shares the same lockdep class key.
On the nested dsa interface architecture, which you illustrated,
the same lockdep class key will be used in __dev_queue_xmit() because
dsa doesn't have LLTX.
So that lockdep detects deadlock because the same lockdep class key is
used recursively although actually the different locks are used.
There are some ways to fix this problem.
1. using NETIF_F_LLTX flag.
If possible, using the LLTX flag is a very clear way for it.
But I'm so sorry I don't know whether the dsa could have LLTX or not.
2. using dynamic lockdep again.
It means that each interface uses a separate lockdep class key.
So, lockdep will not detect recursive locking.
But this way has a problem that it could consume lockdep class key
too many.
Currently, lockdep can have 8192 lockdep class keys.
- you can see this number with the following command.
cat /proc/lockdep_stats
lock-classes: 1251 [max: 8192]
...
The [max: 8192] means that the maximum number of lockdep class keys.
If too many lockdep class keys are registered, lockdep stops to work.
So, using a dynamic(separated) lockdep class key should be considered
carefully.
In addition, updating lockdep class key routine might have to be existing.
(lockdep_register_key(), lockdep_set_class(), lockdep_unregister_key())
3. Using lockdep subclass.
A lockdep class key could have 8 subclasses.
The different subclass is considered different locks by lockdep
infrastructure.
But "lock-classes" is not counted by subclasses.
So, it could avoid stopping lockdep infrastructure by an overflow of
lockdep class keys.
This approach should also have an updating lockdep class key routine.
(lockdep_set_subclass())
4. Using nonvalidate lockdep class key.
The lockdep infrastructure supports nonvalidate lockdep class key type.
It means this lockdep is not validated by lockdep infrastructure.
So, the splat will not happen but lockdep couldn't detect real deadlock
case because lockdep really doesn't validate it.
I think this should be used for really special cases.
(lockdep_set_novalidate_class())
Further discussion here:
https://patchwork.ozlabs.org/project/netdev/patch/20200503052220.4536-2-xiyou.wangcong@gmail.com/
There appears to be no negative side-effect to declaring lockless TX for
the DSA virtual interfaces, which means they handle their own locking.
So that's what we do to make the splat go away.
Patch tested in a wide variety of cases: unicast, multicast, PTP, etc.
Fixes: ab92d68fc22f ("net: core: add generic lockdep keys")
Suggested-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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copy the corresponding pieces of init_fpstate into the gaps instead.
Cc: stable@kernel.org
Tested-by: Alexander Potapenko <glider@google.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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As explained in other commits before (b9cd75e66895 and 87b0f983f66f),
ocelot switches have a single egress-untagged VLAN per port, and the
driver would deny adding a second one while an egress-untagged VLAN
already exists.
But on the CPU port (where the VLAN configuration is implicit, because
there is no net device for the bridge to control), the DSA core attempts
to add a VLAN using the same flags as were used for the front-panel
port. This would make adding any untagged VLAN fail due to the CPU port
rejecting the configuration:
bridge vlan add dev swp0 vid 100 pvid untagged
[ 1865.854253] mscc_felix 0000:00:00.5: Port already has a native VLAN: 1
[ 1865.860824] mscc_felix 0000:00:00.5: Failed to add VLAN 100 to port 5: -16
(note that port 5 is the CPU port and not the front-panel swp0).
So this hardware will send all VLANs as tagged towards the CPU.
Fixes: 56051948773e ("net: dsa: ocelot: add driver for Felix switch family")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Clang-10 and clang-11 run into a corner case of the register
allocator on 32-bit ARM, leading to excessive stack usage from
register spilling:
net/bridge/br_multicast.c:2422:6: error: stack frame size of 1472 bytes in function 'br_multicast_get_stats' [-Werror,-Wframe-larger-than=]
Work around this by marking one of the internal functions as
noinline_for_stack.
Link: https://bugs.llvm.org/show_bug.cgi?id=45802#c9
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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There may be a race between nvme_reap_pending_cqes() and nvme_poll(), e.g.,
when doing live reset while polling the nvme device.
CPU X CPU Y
nvme_poll()
nvme_dev_disable()
-> nvme_stop_queues()
-> nvme_suspend_io_queues()
-> nvme_suspend_queue()
-> spin_lock(&nvmeq->cq_poll_lock);
-> nvme_reap_pending_cqes()
-> nvme_process_cq() -> nvme_process_cq()
In the above scenario, the nvme_process_cq() for the same queue may be
running on both CPU X and CPU Y concurrently.
It is much more easier to reproduce the issue when CONFIG_PREEMPT is
enabled in kernel. When CONFIG_PREEMPT is disabled, it would take longer
time for nvme_stop_queues()-->blk_mq_quiesce_queue() to wait for grace
period.
This patch protects nvme_process_cq() with nvmeq->cq_poll_lock in
nvme_reap_pending_cqes().
Fixes: fa46c6fb5d61 ("nvme/pci: move cqe check after device shutdown")
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The accept(2) is an "input" socket interface, so we should use
SO_RCVTIMEO instead of SO_SNDTIMEO to set the timeout.
So this patch replace sock_sndtimeo() with sock_rcvtimeo() to
use the right timeout in the vsock_accept().
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Prior to this change the correct value for the used counter is calculated
but not stored nor, therefore, propagated to user-space. In use-cases such
as OVS use-case at least this results in active flows being removed from
the hardware datapath. Which results in both unnecessary flow tear-down
and setup, and packet processing on the host.
This patch addresses the problem by saving the calculated used value
which allows the value to propagate to user-space.
Found by inspection.
Fixes: aa6ce2ea0c93 ("nfp: flower: support stats update for merge flows")
Signed-off-by: Heinrich Kuhn <heinrich.kuhn@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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this command hangs forever:
# tc qdisc add dev eth0 root fq_pie flows 65536
watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [tc:1028]
[...]
CPU: 1 PID: 1028 Comm: tc Not tainted 5.7.0-rc6+ #167
RIP: 0010:fq_pie_init+0x60e/0x8b7 [sch_fq_pie]
Code: 4c 89 65 50 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 2a 02 00 00 48 8d 7d 10 4c 89 65 58 48 89 f8 48 c1 e8 03 42 80 3c 30 00 <0f> 85 a7 01 00 00 48 8d 7d 18 48 c7 45 10 46 c3 23 00 48 89 f8 48
RSP: 0018:ffff888138d67468 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff9200018d2b2 RBX: ffff888139c1c400 RCX: ffffffffffffffff
RDX: 000000000000c5e8 RSI: ffffc900000e5000 RDI: ffffc90000c69590
RBP: ffffc90000c69580 R08: fffffbfff79a9699 R09: fffffbfff79a9699
R10: 0000000000000700 R11: fffffbfff79a9698 R12: ffffc90000c695d0
R13: 0000000000000000 R14: dffffc0000000000 R15: 000000002347c5e8
FS: 00007f01e1850e40(0000) GS:ffff88814c880000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000067c340 CR3: 000000013864c000 CR4: 0000000000340ee0
Call Trace:
qdisc_create+0x3fd/0xeb0
tc_modify_qdisc+0x3be/0x14a0
rtnetlink_rcv_msg+0x5f3/0x920
netlink_rcv_skb+0x121/0x350
netlink_unicast+0x439/0x630
netlink_sendmsg+0x714/0xbf0
sock_sendmsg+0xe2/0x110
____sys_sendmsg+0x5b4/0x890
___sys_sendmsg+0xe9/0x160
__sys_sendmsg+0xd3/0x170
do_syscall_64+0x9a/0x370
entry_SYSCALL_64_after_hwframe+0x44/0xa9
we can't accept 65536 as a valid number for 'nflows', because the loop on
'idx' in fq_pie_init() will never end. The extack message is correct, but
it doesn't say that 0 is not a valid number for 'flows': while at it, fix
this also. Add a tdc selftest to check correct validation of 'flows'.
CC: Ivan Vecera <ivecera@redhat.com>
Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fanotify FAN_DIR_MODIFY disabling from Jan Kara:
"A single patch that disables FAN_DIR_MODIFY support that was merged in
this merge window.
When discussing further functionality we realized it may be more
logical to guard it with a feature flag or to call things slightly
differently (or maybe not) so let's not set the API in stone for now."
* tag 'fsnotify_for_v5.7-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fanotify: turn off support for FAN_DIR_MODIFY
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
- Reverted stricter synchronization for cgroup recursive stats which
was prepping it for event counter usage which never got merged. The
change was causing performation regressions in some cases.
- Restore bpf-based device-cgroup operation even when cgroup1 device
cgroup is disabled.
- An out-param init fix.
* 'for-5.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
device_cgroup: Cleanup cgroup eBPF device filter code
xattr: fix uninitialized out-param
Revert "cgroup: Add memory barriers to plug cgroup_rstat_updated() race window"
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Fix use after free when user user space request uobject concurrently for
the same object, within the RCU grace period.
In that case, remove_handle_idr_uobject() is called twice and we will have
an extra put on the uobject which cause use after free. Fix it by leaving
the uobject write locked after it was removed from the idr.
Call to rdma_lookup_put_uobject with UVERBS_LOOKUP_DESTROY instead of
UVERBS_LOOKUP_WRITE will do the work.
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 1381 at lib/refcount.c:28 refcount_warn_saturate+0xfe/0x1a0
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 1381 Comm: syz-executor.0 Not tainted 5.5.0-rc3 #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x94/0xce
panic+0x234/0x56f
__warn+0x1cc/0x1e1
report_bug+0x200/0x310
fixup_bug.part.11+0x32/0x80
do_error_trap+0xd3/0x100
do_invalid_op+0x31/0x40
invalid_op+0x1e/0x30
RIP: 0010:refcount_warn_saturate+0xfe/0x1a0
Code: 0f 0b eb 9b e8 23 f6 6d ff 80 3d 6c d4 19 03 00 75 8d e8 15 f6 6d ff 48 c7 c7 c0 02 55 bd c6 05 57 d4 19 03 01 e8 a2 58 49 ff <0f> 0b e9 6e ff ff ff e8 f6 f5 6d ff 80 3d 42 d4 19 03 00 0f 85 5c
RSP: 0018:ffffc90002df7b98 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88810f6a193c RCX: ffffffffba649009
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88811b0283cc
RBP: 0000000000000003 R08: ffffed10236060e3 R09: ffffed10236060e3
R10: 0000000000000001 R11: ffffed10236060e2 R12: ffff88810f6a193c
R13: ffffc90002df7d60 R14: 0000000000000000 R15: ffff888116ae6a08
uverbs_uobject_put+0xfd/0x140
__uobj_perform_destroy+0x3d/0x60
ib_uverbs_close_xrcd+0x148/0x170
ib_uverbs_write+0xaa5/0xdf0
__vfs_write+0x7c/0x100
vfs_write+0x168/0x4a0
ksys_write+0xc8/0x200
do_syscall_64+0x9c/0x390
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b49
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f759d122c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000073bfa8 RCX: 0000000000465b49
RDX: 000000000000000c RSI: 0000000020000080 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f759d1236bc
R13: 00000000004ca27c R14: 000000000070de40 R15: 00000000ffffffff
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: 0x39400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
Fixes: 7452a3c745a2 ("IB/uverbs: Allow RDMA_REMOVE_DESTROY to work concurrently with disassociate")
Link: https://lore.kernel.org/r/20200527135534.482279-1-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
|
|
FAN_DIR_MODIFY has been enabled by commit 44d705b0370b ("fanotify:
report name info for FAN_DIR_MODIFY event") in 5.7-rc1. Now we are
planning further extensions to the fanotify API and during that we
realized that FAN_DIR_MODIFY may behave slightly differently to be more
consistent with extensions we plan. So until we finalize these
extensions, let's not bind our hands with exposing FAN_DIR_MODIFY to
userland.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull execve fix from Eric Biederman:
"While working on my exec cleanups I found a bug in exec that winds up
miscomputing the ambient credentials during exec. Andy appears to have
to been confused as to why credentials are computed for both the
script and the interpreter
From the original patch description:
[3] Linux very confusingly processes both the script and the
interpreter if applicable, for reasons that elude me. The results
from thinking about a script's file capabilities and/or setuid
bits are mostly discarded.
The only value in struct cred that gets changed in cap_bprm_set_creds
that I could find that might persist between the script and the
interpreter was cap_ambient. Which is fixed with this trivial change"
* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
exec: Always set cap_ambient in cap_bprm_set_creds
|
|
Building this driver with "clang -O3" produces a link error
after the compiler partially unrolls the loop and 256ms
becomes a compile-time constant that triggers the check
in udelay():
ld.lld: error: undefined symbol: __bad_udelay
>>> referenced by applesmc.c
>>> hwmon/applesmc.o:(read_smc) in archive drivers/built-in.a
I can see no reason against using a sleeping function here,
as no part of the driver runs in atomic context, so instead use
usleep_range() with a wide range and use jiffies for the
end condition.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200527135207.1118624-1-arnd@arndb.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
|
|
Hibernation via snapshot device requires write permission to the swap
block device, the one that more often (but not necessarily) is used to
store the hibernation image.
With this patch, such permissions are granted iff:
1) snapshot device config option is enabled
2) swap partition is used as resume device
In other circumstances the swap device is not writable from userspace.
In order to achieve this, every write attempt to a swap device is
checked against the device configured as part of the uswsusp API [0]
using a pointer to the inode struct in memory. If the swap device being
written was not configured for resuming, the write request is denied.
NOTE: this implementation works only for swap block devices, where the
inode configured by swapon (which sets S_SWAPFILE) is the same used
by SNAPSHOT_SET_SWAP_AREA.
In case of swap file, SNAPSHOT_SET_SWAP_AREA indeed receives the inode
of the block device containing the filesystem where the swap file is
located (+ offset in it) which is never passed to swapon and then has
not set S_SWAPFILE.
As result, the swap file itself (as a file) has never an option to be
written from userspace. Instead it remains writable if accessed directly
from the containing block device, which is always writeable from root.
[0] Documentation/power/userland-swsusp.rst
v2:
- rename is_hibernate_snapshot_dev() to is_hibernate_resume_dev()
- fix description so to correctly refer to the resume device
Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com>
Acked-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
Commit ea6f3af4c5e63f69 ("ACPI: GED: add support for _Exx / _Lxx handler
methods") added a reference to the 'triggering' field of either the
normal or the extended ACPI IRQ resource struct, but inadvertently used
the wrong pointer in the latter case. Note that both pointers refer to the
same union, and the 'triggering' field appears at the same offset in both
struct types, so it currently happens to work by accident. But let's fix
it nonetheless
Fixes: ea6f3af4c5e63f69 ("ACPI: GED: add support for _Exx / _Lxx handler methods")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
Dave Airlie reported the following lockdep complaint:
> ======================================================
> WARNING: possible circular locking dependency detected
> 5.7.0-0.rc5.20200515git1ae7efb38854.1.fc33.x86_64 #1 Not tainted
> ------------------------------------------------------
> kswapd0/159 is trying to acquire lock:
> ffff9b38d01a4470 (&xfs_nondir_ilock_class){++++}-{3:3},
> at: xfs_ilock+0xde/0x2c0 [xfs]
>
> but task is already holding lock:
> ffffffffbbb8bd00 (fs_reclaim){+.+.}-{0:0}, at:
> __fs_reclaim_acquire+0x5/0x30
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #1 (fs_reclaim){+.+.}-{0:0}:
> fs_reclaim_acquire+0x34/0x40
> __kmalloc+0x4f/0x270
> kmem_alloc+0x93/0x1d0 [xfs]
> kmem_alloc_large+0x4c/0x130 [xfs]
> xfs_attr_copy_value+0x74/0xa0 [xfs]
> xfs_attr_get+0x9d/0xc0 [xfs]
> xfs_get_acl+0xb6/0x200 [xfs]
> get_acl+0x81/0x160
> posix_acl_xattr_get+0x3f/0xd0
> vfs_getxattr+0x148/0x170
> getxattr+0xa7/0x240
> path_getxattr+0x52/0x80
> do_syscall_64+0x5c/0xa0
> entry_SYSCALL_64_after_hwframe+0x49/0xb3
>
> -> #0 (&xfs_nondir_ilock_class){++++}-{3:3}:
> __lock_acquire+0x1257/0x20d0
> lock_acquire+0xb0/0x310
> down_write_nested+0x49/0x120
> xfs_ilock+0xde/0x2c0 [xfs]
> xfs_reclaim_inode+0x3f/0x400 [xfs]
> xfs_reclaim_inodes_ag+0x20b/0x410 [xfs]
> xfs_reclaim_inodes_nr+0x31/0x40 [xfs]
> super_cache_scan+0x190/0x1e0
> do_shrink_slab+0x184/0x420
> shrink_slab+0x182/0x290
> shrink_node+0x174/0x680
> balance_pgdat+0x2d0/0x5f0
> kswapd+0x21f/0x510
> kthread+0x131/0x150
> ret_from_fork+0x3a/0x50
>
> other info that might help us debug this:
>
> Possible unsafe locking scenario:
>
> CPU0 CPU1
> ---- ----
> lock(fs_reclaim);
> lock(&xfs_nondir_ilock_class);
> lock(fs_reclaim);
> lock(&xfs_nondir_ilock_class);
>
> *** DEADLOCK ***
>
> 4 locks held by kswapd0/159:
> #0: ffffffffbbb8bd00 (fs_reclaim){+.+.}-{0:0}, at:
> __fs_reclaim_acquire+0x5/0x30
> #1: ffffffffbbb7cef8 (shrinker_rwsem){++++}-{3:3}, at:
> shrink_slab+0x115/0x290
> #2: ffff9b39f07a50e8
> (&type->s_umount_key#56){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0
> #3: ffff9b39f077f258
> (&pag->pag_ici_reclaim_lock){+.+.}-{3:3}, at:
> xfs_reclaim_inodes_ag+0x82/0x410 [xfs]
This is a known false positive because inodes cannot simultaneously be
getting reclaimed and the target of a getxattr operation, but lockdep
doesn't know that. We can (selectively) shut up lockdep until either
it gets smarter or we change inode reclaim not to require the ILOCK by
applying a stupid GFP_NOLOCKDEP bandaid.
Reported-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Tested-by: Dave Airlie <airlied@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
When writing to a delalloc region in the data fork, commit the new
allocations (of the da reservation) as unwritten so that the mappings
are only marked written once writeback completes successfully. This
fixes the problem of stale data exposure if the system goes down during
targeted writeback of a specific region of a file, as tested by
generic/042.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
Refactor xfs_iomap_prealloc_size to be the function that dynamically
computes the per-file preallocation size by moving the allocsize= case
to the caller. Break up the huge comment preceding the function to
annotate the relevant parts of the code, and remove the impossible
check_writeio case.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
When we're estimating a new speculative preallocation length for an
extending write, we should walk backwards through the extent list to
determine the number of number of blocks that are physically and
logically contiguous with the write offset, and use that as an input to
the preallocation size computation.
This way, preallocation length is truly measured by the effectiveness of
the allocator in giving us contiguous allocations without being
influenced by the state of a given extent. This fixes both the problem
where ZERO_RANGE within an EOF can reduce preallocation, and prevents
the unnecessary shrinkage of preallocation when delalloc extents are
turned into unwritten extents.
This was found as a regression in xfs/014 after changing delalloc writes
to create unwritten extents during writeback.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
During writeback, it's possible for the quota block reservation in
xfs_iomap_write_unwritten to fail with EDQUOT because we hit the quota
limit. This causes writeback errors for data that was already written
to disk, when it's not even guaranteed that the bmbt will expand to
exceed the quota limit. Irritatingly, this condition is reported to
userspace as EIO by fsync, which is confusing.
We wrote the data, so allow the reservation. That might put us slightly
above the hard limit, but it's better than losing data after a write.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
|
|
The perag structure already has a pointer to the xfs_mount, so we don't
need to pass that separately and can drop it. Having done that, move
iter_flags so that the argument order is the same between xfs_inode_walk
and xfs_inode_walk_ag. The latter will make things less confusing for a
future patch that enables background scanning work to be done in
parallel.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
We're not very consistent about function names for the incore inode
iteration function. Turn them all into xfs_inode_walk* variants.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
|
|
Move the xfs_inode_ag_iterator function to be nearer xfs_inode_ag_walk
so that we don't have to scroll back and forth to figure out how the
incore inode walking function works. No functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
This is a boolean variable, so use the bool type.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
There are a number of predicate functions that help the incore inode
walking code decide if we really want to apply the iteration function to
the inode. These are boolean decisions, so change the return types to
boolean to match.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
Refactor the two eofb-matching logics into a single helper so that we
don't repeat ourselves.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
|
|
This is now a pointless wrapper, so kill it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
The incore inode walk code passes a flags argument and a pointer from
the xfs_inode_ag_iterator caller all the way to the iteration function.
We can reduce the function complexity by passing flags through the
private pointer.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
Combine xfs_inode_ag_iterator_flags and xfs_inode_ag_iterator_tag into a
single wrapper function since there's only one caller of the _flags
variant.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
Not used by anyone, so get rid of it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
Use XFS_ICI_NO_TAG instead of -1 when appropriate.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
Move xfs_fs_eofblocks_from_user into the only file that actually uses
it, so that we don't have this function cluttering up the header file.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
The only grace period which can be set in the kernel today is for id 0,
i.e. the default grace period for all users. However, setting an
individual grace period is useful; for example:
Alice has a soft quota of 100 inodes, and a hard quota of 200 inodes
Alice uses 150 inodes, and enters a short grace period
Alice really needs to use those 150 inodes past the grace period
The administrator extends Alice's grace period until next Monday
vfs quota users such as ext4 can do this today, with setquota -T
To enable this for XFS, we simply move the timelimit assignment out
from under the (id == 0) test. Default setting remains under (id == 0).
Note that this now is consistent with how we set warnings.
(Userspace requires updates to enable this as well; xfs_quota needs to
parse new options, and setquota needs to set appropriate field flags.)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
Move timers and warnings out of xfs_quotainfo and into xfs_def_quota
so that we can utilize them on a per-type basis, rather than enforcing
them based on the values found in the first enabled quota type.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[zlang: new way to get defquota in xfs_qm_init_timelimits]
[zlang: remove redundant defq assign]
Signed-off-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
xfs_get_defquota() currently takes an xfs_dquot, and from that obtains
the type of default quota we should get (user/group/project).
But early in init, we don't have access to a fully set up quota, so
that's not possible. The next patch needs go set up default quota
timers early, so switch xfs_get_defquota to take an explicit type
and add a helper function to obtain that type from an xfs_dquot
for the existing callers.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
Pass xfs_dquot rather than xfs_disk_dquot to xfs_qm_adjust_dqtimers;
this makes it symmetric with xfs_qm_adjust_dqlimits and will help
the next patch.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
There is a fair bit of whitespace damage in the quota code, so
fix up enough of it that subsequent patches are restricted to
functional change to aid review.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
XFS project quota treats project hierarchies as "mini filesysems" and
so rather than -EDQUOT, the intent is to return -ENOSPC when a quota
reservation fails, but this behavior is not consistent.
The only place we make a decision between -EDQUOT and -ENOSPC
returns based on quota type is in xfs_trans_dqresv().
This behavior is currently controlled by whether or not the
XFS_QMOPT_ENOSPC flag gets passed into the quota reservation. However,
its use is not consistent; paths such as xfs_create() and xfs_symlink()
don't set the flag, so a reservation failure will return -EDQUOT for
project quota reservation failures rather than -ENOSPC for these sorts
of operations, even for project quota:
# mkdir mnt/project
# xfs_quota -x -c "project -s -p mnt/project 42" mnt
# xfs_quota -x -c 'limit -p isoft=2 ihard=3 42' mnt
# touch mnt/project/file{1,2,3}
touch: cannot touch ‘mnt/project/file3’: Disk quota exceeded
We can make this consistent by not requiring the flag to be set at the
top of the callchain; instead we can simply test whether we are
reserving a project quota with XFS_QM_ISPDQ in xfs_trans_dqresv and if
so, return -ENOSPC for that failure. This removes the need for the
XFS_QMOPT_ENOSPC altogether and simplifies the code a fair bit.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
Long ago, group & project quota were mutually exclusive, and so
when we turned on XFS_QMOPT_ENOSPC ("return ENOSPC if project quota
is exceeded") when project quota was enabled, we only needed to
disable it again for user quota.
When group & project quota got separated, this got missed, and as a
result if project quota is enabled and group quota is exceeded, the
error code returned is incorrectly returned as ENOSPC not EDQUOT.
Fix this by stripping XFS_QMOPT_ENOSPC out of flags for group
quota when we try to reserve the space.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
It's a global atomic counter, and we are hitting it at a rate of
half a million transactions a second, so it's bouncing the counter
cacheline all over the place on large machines. We don't actually
need it anymore - it used to be required because the VFS freeze code
could not track/prevent filesystem transactions that were running,
but that problem no longer exists.
Hence to remove the counter, we simply have to ensure that nothing
calls xfs_sync_sb() while we are trying to quiesce the filesytem.
That only happens if the log worker is still running when we call
xfs_quiesce_attr(). The log worker is cancelled at the end of
xfs_quiesce_attr() by calling xfs_log_quiesce(), so just call it
early here and then we can remove the counter altogether.
Concurrent create, 50 million inodes, identical 16p/16GB virtual
machines on different physical hosts. Machine A has twice the CPU
cores per socket of machine B:
unpatched patched
machine A: 3m16s 2m00s
machine B: 4m04s 4m05s
Create rates:
unpatched patched
machine A: 282k+/-31k 468k+/-21k
machine B: 231k+/-8k 233k+/-11k
Concurrent rm of same 50 million inodes:
unpatched patched
machine A: 6m42s 2m33s
machine B: 4m47s 4m47s
The transaction rate on the fast machine went from just under
300k/sec to 700k/sec, which indicates just how much of a bottleneck
this atomic counter was.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
|
|
Seeing massive cpu usage from xfs_agino_range() on one machine;
instruction level profiles look similar to another machine running
the same workload, only one machine is consuming 10x as much CPU as
the other and going much slower. The only real difference between
the two machines is core count per socket. Both are running
identical 16p/16GB virtual machine configurations
Machine A:
25.83% [k] xfs_agino_range
12.68% [k] __xfs_dir3_data_check
6.95% [k] xfs_verify_ino
6.78% [k] xfs_dir2_data_entry_tag_p
3.56% [k] xfs_buf_find
2.31% [k] xfs_verify_dir_ino
2.02% [k] xfs_dabuf_map.constprop.0
1.65% [k] xfs_ag_block_count
And takes around 13 minutes to remove 50 million inodes.
Machine B:
13.90% [k] __pv_queued_spin_lock_slowpath
3.76% [k] do_raw_spin_lock
2.83% [k] xfs_dir3_leaf_check_int
2.75% [k] xfs_agino_range
2.51% [k] __raw_callee_save___pv_queued_spin_unlock
2.18% [k] __xfs_dir3_data_check
2.02% [k] xfs_log_commit_cil
And takes around 5m30s to remove 50 million inodes.
Suspect is cacheline contention on m_sectbb_log which is used in one
of the macros in xfs_agino_range. This is a read-only variable but
shares a cacheline with m_active_trans which is a global atomic that
gets bounced all around the machine.
The workload is trying to run hundreds of thousands of transactions
per second and hence cacheline contention will be occurring on this
atomic counter. Hence xfs_agino_range() is likely just be an
innocent bystander as the cache coherency protocol fights over the
cacheline between CPU cores and sockets.
On machine A, this rearrangement of the struct xfs_mount
results in the profile changing to:
9.77% [kernel] [k] xfs_agino_range
6.27% [kernel] [k] __xfs_dir3_data_check
5.31% [kernel] [k] __pv_queued_spin_lock_slowpath
4.54% [kernel] [k] xfs_buf_find
3.79% [kernel] [k] do_raw_spin_lock
3.39% [kernel] [k] xfs_verify_ino
2.73% [kernel] [k] __raw_callee_save___pv_queued_spin_unlock
Vastly less CPU usage in xfs_agino_range(), but still 3x the amount
of machine B and still runs substantially slower than it should.
Current rm -rf of 50 million files:
vanilla patched
machine A 13m20s 6m42s
machine B 5m30s 5m02s
It's an improvement, hence indicating that separation and further
optimisation of read-only global filesystem data is worthwhile, but
it clearly isn't the underlying issue causing this specific
performance degradation.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Shaokun Zhang reported that XFS was using substantial CPU time in
percpu_count_sum() when running a single threaded benchmark on
a high CPU count (128p) machine from xfs_mod_ifree(). The issue
is that the filesystem is empty when the benchmark runs, so inode
allocation is running with a very low inode free count.
With the percpu counter batching, this means comparisons when the
counter is less that 128 * 256 = 32768 use the slow path of adding
up all the counters across the CPUs, and this is expensive on high
CPU count machines.
The summing in xfs_mod_ifree() is only used to fire an assert if an
underrun occurs. The error is ignored by the higher level code.
Hence this is really just debug code and we don't need to run it
on production kernels, nor do we need such debug checks to return
error values just to trigger an assert.
Finally, xfs_mod_icount/xfs_mod_ifree are only called from
xfs_trans_unreserve_and_mod_sb(), so get rid of them and just
directly call the percpu_counter_add/percpu_counter_compare
functions. The compare functions are now run only on debug builds as
they are internal to ASSERT() checks and so only compiled in when
ASSERTs are active (CONFIG_XFS_DEBUG=y or CONFIG_XFS_WARN=y).
Reported-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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xfs: gut error handling in xfs_trans_unreserve_and_mod_sb()
From: Dave Chinner <dchinner@redhat.com>
The error handling in xfs_trans_unreserve_and_mod_sb() is largely
incorrect - rolling back the changes in the transaction if only one
counter underruns makes all the other counters incorrect. We still
allow the change to proceed and committing the transaction, except
now we have multiple incorrect counters instead of a single
underflow.
Further, we don't actually report the error to the caller, so this
is completely silent except on debug kernels that will assert on
failure before we even get to the rollback code. Hence this error
handling is broken, untested, and largely unnecessary complexity.
Just remove it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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There is a generic, kernel wide configuration symbol for enabling the
IOMMU specific bits: CONFIG_IOMMU_API. Implementations (including
INTEL_IOMMU and AMD_IOMMU driver) select it so use it here as well.
This makes the conditional archdata.iommu field consistent with other
platforms and also fixes any compile test builds of other IOMMU drivers,
when INTEL_IOMMU or AMD_IOMMU are not selected).
For the case when INTEL_IOMMU/AMD_IOMMU and COMPILE_TEST are not
selected, this should create functionally equivalent code/choice. With
COMPILE_TEST this field could appear if other IOMMU drivers are chosen
but neither INTEL_IOMMU nor AMD_IOMMU are not.
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: e93a1695d7fb ("iommu: Enable compile testing for some of drivers")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200518120855.27822-2-krzk@kernel.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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