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1,058,063 commits

Author SHA1 Message Date
Robert Hancock
92817dad7d net: phylink: Support disabling autonegotiation for PCS
The auto-negotiation state in the PCS as set by
phylink_mii_c22_pcs_config was previously always enabled when the
driver is configured for in-band autonegotiation, even if
autonegotiation was disabled on the interface with ethtool. Update the
code to set the BMCR_ANENABLE bit based on the interface's
autonegotiation enabled state.

Update phylink_mii_c22_pcs_get_state to not check
autonegotiation-related fields when autonegotiation is disabled.

Update phylink_mac_pcs_get_state to initialize the state based on the
interface's configured speed, duplex and pause parameters rather than
to unknown when autonegotiation is disabled, before calling the
driver's pcs_get_state functions, as they are not likely to provide
meaningful data for these fields when autonegotiation is disabled. In
this case the driver is really just filling in the link state field.

Note that in cases where there is a downstream PHY connected, such as
with SGMII and a copper PHY, the configuration set by ethtool is
handled by phy_ethtool_ksettings_set and not propagated to the PCS.
This is correct since SGMII or 1000Base-X autonegotiation with the PCS
should normally still be used even if the copper side has disabled it.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-19 13:07:36 +01:00
Sebastian Andrzej Siewior
e22db7bd55 net: sched: Allow statistics reads from softirq.
Eric reported that the rate estimator reads statics from the softirq
which in turn triggers a warning introduced in the statistics rework.

The warning is too cautious. The updates happen in the softirq context
so reads from softirq are fine since the writes can not be preempted.
The updates/writes happen during qdisc_run() which ensures one writer
and the softirq context.
The remaining bad context for reading statistics remains in hard-IRQ
because it may preempt a writer.

Fixes: 29cbcd8582 ("net: sched: Remove Qdisc::running sequence counter")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-19 13:07:35 +01:00
Russell King (Oracle)
dc90604b58 net: phylink: rejig SFP interface selection in ksettings_set()
Commit ea269a6f72 ("net: phylink: Update SFP selected interface on
advertising changes") added a better solution to selecting the
interface mode for SFPs using the advertisement mask. This method will
work for mvneta and mvpp2 when selecting between 2500base-X and
1000base-X without needing to use the basex helper, or indicate that
we support both 1000base-X and 2500base-X when in either of these two
interface modes.

Hence, we need to eliminate the validation prior to selecting the
interface, otherwise when we clean up mvneta's validation function, we
will end up locking to 2500base-X as we validate with an interface mode
of PHY_INERFACE_MODE_2500BASEX.

The supported mask will already have been reduced down to the union of
support for the SFP and MAC already, so we can be confident that the
advertisement mask is already appropriately restricted. We only need to
select the appropriate interface, and then revalidate with the new
interface mode.

We get rid of the check for pl->sfp_port too, this is meaningless here
as it doesn't get cleared when a module is removed, so it doesn't
indicate if a module is present. Just rely on pl->sfp_bus.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-19 13:07:35 +01:00
Tom Lendacky
e7d445ab26 x86/sme: Use #define USE_EARLY_PGTABLE_L5 in mem_encrypt_identity.c
When runtime support for converting between 4-level and 5-level pagetables
was added to the kernel, the SME code that built pagetables was updated
to use the pagetable functions, e.g. p4d_offset(), etc., in order to
simplify the code. However, the use of the pagetable functions in early
boot code requires the use of the USE_EARLY_PGTABLE_L5 #define in order to
ensure that the proper definition of pgtable_l5_enabled() is used.

Without the #define, pgtable_l5_enabled() is #defined as
cpu_feature_enabled(X86_FEATURE_LA57). In early boot, the CPU features
have not yet been discovered and populated, so pgtable_l5_enabled() will
return false even when 5-level paging is enabled. This causes the SME code
to always build 4-level pagetables to perform the in-place encryption.
If 5-level paging is enabled, switching to the SME pagetables results in
a page-fault that kills the boot.

Adding the #define results in pgtable_l5_enabled() using the
__pgtable_l5_enabled variable set in early boot and the SME code building
pagetables for the proper paging level.

Fixes: aad983913d ("x86/mm/encrypt: Simplify sme_populate_pgd() and sme_populate_pgd_large()")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org> # 4.18.x
Link: https://lkml.kernel.org/r/2cb8329655f5c753905812d951e212022a480475.1634318656.git.thomas.lendacky@amd.com
2021-10-19 14:07:17 +02:00
Jens Axboe
6155631a0c block: align blkdev_dio inlined bio to a cacheline
We get all sorts of unreliable and funky results since the bio is
designed to align on a cacheline, which it does not when inlined like
this.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:55:52 -06:00
Jens Axboe
e028f167ec block: move blk_mq_tag_to_rq() inline
This is in the fast path of driver issue or completion, and it's a single
array index operation. Move it inline to avoid a function call for it.

This does mean making struct blk_mq_tags block layer public, but there's
not really much in there.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:55:41 -06:00
Jens Axboe
df87eb0fce block: get rid of plug list sorting
Even if we have multiple queues in the plug list, chances that they
are very interspersed is minimal. Don't bother spending CPU cycles
sorting the list.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:55:26 -06:00
Jens Axboe
87c037d11b block: return whether or not to unplug through boolean
Instead of returning the same queue request through a request pointer,
use a boolean to accomplish the same.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:55:04 -06:00
Christoph Hellwig
8a7d267b4a block: don't call blk_status_to_errno in blk_update_request
We only need to call it to resolve the blk_status_t -> errno mapping for
tracing, so move the conversion into the tracepoints that are not called
at all when tracing isn't enabled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:54:57 -06:00
Borislav Petkov
c688bd5dc9 x86/sev: Carve out HV call's return value verification
Carve out the verification of the HV call return value into a separate
helper and make it more readable.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/YVbYWz%2B8J7iMTJjc@zn.tnic
2021-10-19 13:54:47 +02:00
Jens Axboe
db9a02baa2 block: move bdev_read_only() into the header
This is called for every write in the fast path, move it inline next
to get_disk_ro() which is called internally.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:53:22 -06:00
Jens Axboe
5ca7a8b3f6 io_uring: inform block layer of how many requests we are submitting
The block layer can use this knowledge to make smarter decisions on
how to handle the request, if it knows that N more may be coming. Switch
to using blk_start_plug_nr_ios() to pass in that information.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
88459b50b4 io_uring: simplify io_file_supports_nowait()
Make sure that REQ_F_SUPPORT_NOWAIT is always set io_prep_rw(), and so
we can stop caring about setting it down the line simplifying
io_file_supports_nowait().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/60c8f1f5e2cb45e00f4897b2cec10c5b3669da91.1634425438.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
35645ac3c1 io_uring: combine REQ_F_NOWAIT_{READ,WRITE} flags
Merge REQ_F_NOWAIT_READ and REQ_F_NOWAIT_WRITE into one flag, i.e.
REQ_F_SUPPORT_NOWAIT. First it gets rid of dependence on CONFIG_64BIT
but also simplifies the code.

One thing to consider is when we don't have ->{read,write}_iter and go
through loop_rw_iter(). Just fail it with -EAGAIN if we expect nowait
behaviour but not sure whether it supports it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f832a20e5186c2e79c6519280c238f559a1d2bbc.1634425438.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
e74ead135b io_uring: arm poll for non-nowait files
Don't check if we can do nowait before arming apoll, there are several
reasons for that. First, we don't care much about files that don't
support nowait. Second, it may be useful -- we don't want to be taking
away extra workers from io-wq when it can go in some async. Even if it
will go through io-wq eventually, it make difference in the numbers of
workers actually used. And the last one, it's needed to clean nowait in
future commits.

[kernel test robot: fix unused-var]

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9d06f3cb2c8b686d970269a87986f154edb83043.1634425438.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Noah Goldstein
b10841c98c fs/io_uring: Prioritise checking faster conditions first in io_write
This commit reorders the conditions in a branch in io_write. The
reorder to check 'ret2 == -EAGAIN' first as checking
'(req->ctx->flags & IORING_SETUP_IOPOLL)' will likely be more
expensive due to 2x memory derefences.

Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
Link: https://lore.kernel.org/r/20211017013229.4124279-1-goldstein.w.n@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
5cb03d6342 io_uring: clean io_prep_rw()
We already store req->file in a variable in io_prep_rw(), just use it
instead of a couple of left references to kicob->ki_filp.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2f5889fc7ab670daefd5ccaedd99416d8355f0ad.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
578c0ee234 io_uring: optimise fixed rw rsrc node setting
Move fixed rw io_req_set_rsrc_node() from rw prep into
io_import_fixed(), if we're using fixed buffers it will always be called
during submission as we save the state in advance,

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/68c06f66d5aa9661f1e4b88d08c52d23528297ec.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
caa8fe6e86 io_uring: return iovec from __io_import_iovec
We pass iovec** into __io_import_iovec(), which should keep it,
initialise and modify accordingly. It's expensive, return it directly
from __io_import_iovec encoding errors with ERR_PTR if needed.

io_import_iovec keeps the old interface, but it's inline and so
everything is optimised nicely.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6230e9769982f03a8f86fa58df24666088c44d3e.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:56 -06:00
Pavel Begunkov
d1d681b084 io_uring: optimise io_import_iovec fixed path
Delay loading req->rw.{addr,len} in io_import_iovec until it's really
needed, so removing extra loads for the fixed path, which doesn't use
them.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3cc48dd0c4f1a37c4ce9aab5784281a2d83ad8be.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
9882131cd9 io_uring: kill io_wq_current_is_worker() in iopoll
Don't decide about locking based on io_wq_current_is_worker(), it's not
consistent with all other code and is expensive, use issue_flags.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7546d5a58efa4360173541c6fe02ee6b8c7b4ea7.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
9983028e76 io_uring: optimise req->ctx reloads
Don't load req->ctx in advance, it takes an extra register and the field
stays valid even after opcode handlers. It also optimises out req->ctx
load in io_iopoll_req_issued() once it's inlined.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1e45ff671c44be0eb904f2e448a211734893fa0b.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
607b6fb801 io_uring: rearrange io_read()/write()
Combine force_nonblock branches (which is already optimised by
compiler), flip branches so the most hot/common path is the first, e.g.
as with non on-stack iov setup, and add extra likely/unlikely
attributions for errror paths.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2c2536c5896d70994de76e387ea09a0402173a3f.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
5e49c973fc io_uring: clean up io_import_iovec
Make io_import_iovec taking struct io_rw_state instead of an iter
pointer. First it takes care of initialising iovec pointer, which can be
forgotten. Even more, we can not init it if not needed, e.g. in case of
IORING_OP_READ_FIXED or IORING_OP_READ. Also hide saving iter_state
inside of it by splitting out an inline function of it to avoid extra
ifs.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b1bbc213a95e5272d4da5867bb977d9acb6f2109.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
51aac424ae io_uring: optimise io_import_iovec nonblock passing
First, change IO_URING_F_NONBLOCK to take sign bit of the int, so
checking for it can be turned into test + sign-based-jump, makes the
binary smaller and may be faster.

Then, instead of passing need_lock boolean into io_import_iovec() just
give it issue_flags, which is already stored somewhere. Saves some space
on stack, a couple of test + cmov operations and other conversions.

note: we still leave
force_nonblock = issue_flags & IO_URING_F_NONBLOCK
variable, but it's optimised out by the compiler into testing
issue_flags directly.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ee96547e692f6c975c229cd82fc721679571a734.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
c88598a92a io_uring: optimise read/write iov state storing
Currently io_read() and io_write() keep separate pointers to an iter and
to struct iov_iter_state, which is not great for register spilling and
requires more on-stack copies. They are both either on-stack or in
req->async_data at the same time, so use struct io_rw_state and keep a
pointer only to it, so having all the state with just one pointer.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5c5e7ffd7dc25fc35075c70411ba99df72f237fa.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
538941e268 io_uring: encapsulate rw state
Add a new struct io_rw_state storing all iov related bits: fast iov,
iterator and iterator state. Not much changes here, simply convert
struct io_async_rw to use it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e8245ffcb568b228a009ec1eb79c993c813679f1.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
258f3a7f84 io_uring: optimise rw comletion handlers
Don't override req->result in io_complete_rw_iopoll() when it's already
of the same value, we have an if just above it, so move the assignment
there. Also, add one simle unlikely() in __io_complete_rw_common().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8dfeb4f84026a20172bcf82c05010abe955874ae.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
f80a50a632 io_uring: prioritise read success path over fails
Rearrange io_read return handling so first we expect it completing
successfully and only then checking for errors, which is a colder path.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c91c7c2da11815ec8b04b5d872f60dc4cde662c5.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
04f34081c5 io_uring: consistent typing for issue_flags
Some of the functions keep issue_flags as int, change those to unsigned.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/04ad43797783bc9cc7567f287ab545518f8e8cf2.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
ab40940247 io_uring: optimise rsrc referencing
Apparently, percpu_ref_put/get() are expensive enough if done per
request, get them in a batch and cache on the submission side to avoid
getting it over and over again. Also, if we're completing under
uring_lock, return refs back into the cache instead of
perfcpu_ref_put(). Pretty similar to how we do tctx->cached_refs
accounting, but fall back to normal putting when we already changed a
rsrc node by the time of free.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b40d8c5bc77d3c9550df8a319117a374ac85f8f4.1633817310.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
a46be971ed io_uring: optimise io_req_set_rsrc_node()
io_req_set_rsrc_node() reloads loads req->ctx, however it's already in
registers in all use cases, so better to pass it as a parameter.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/67a25557b8a51e90bfd578447a6f1671911b05ae.1633817310.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
def77acf43 io_uring: fix io_free_batch_list races
[  158.514382] WARNING: CPU: 5 PID: 15251 at fs/io_uring.c:1141 io_free_batch_list+0x269/0x360
[  158.514426] RIP: 0010:io_free_batch_list+0x269/0x360
[  158.514437] Call Trace:
[  158.514440]  __io_submit_flush_completions+0xde/0x180
[  158.514444]  tctx_task_work+0x14a/0x220
[  158.514447]  task_work_run+0x64/0xa0
[  158.514448]  __do_sys_io_uring_enter+0x7c/0x970
[  158.514450]  __x64_sys_io_uring_enter+0x22/0x30
[  158.514451]  do_syscall_64+0x43/0x90
[  158.514453]  entry_SYSCALL_64_after_hwframe+0x44/0xae

We should not touch request internals including req->comp_list.next
after putting our ref if it's not final, e.g. we can start freeing
requests from the free cache.

Fixed: 62ca9cb93e7f8 ("io_uring: optimise io_free_batch_list()")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b1f4df38fbb8f111f52911a02fd418d0283a4e6f.1634047298.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
0cd3e3ddb4 io_uring: remove extra io_ring_exit_work wake up
task_work_add() takes care of waking up the thread, remove useless
wake_up_process().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/de9a71ee255112dcaed3b5d426be24934e74722c.1633532552.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
4a04d1d148 io_uring: optimise out req->opcode reloading
Looking at the assembly, the compiler decided to reload req->opcode in
io_op_defs[opcode].needs_file instead of one it had in a register, so
store it in a temp variable so it can be optimised out. Also move the
personality block later, it's better for spilling/etc. as it only
depends on @sqe, which we're keeping anyway.

By the way, zero req->opcode if it over IORING_OP_LAST, not a problem,
at the moment but is safer.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6ba869f5f8b7b0f991c87fdf089f0abf87cbe06b.1633532552.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
5a158c6b0d io_uring: reshuffle io_submit_state bits
struct io_submit_state's ->free_list and ->link are hotter and smaller
than ->plug, place them first.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6ad3c15849f50b27ad012c042c73e6e069d22df7.1633532552.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
756ab7c0ec io_uring: safer fallback_work free
Add extra wq flushing for fallback_work, that's not necessary but safer
if invariants of io_fallback_req_func() change.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/24179419d6748516299600bc914f50b9e0b02275.1633532552.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
6d63416dc5 io_uring: optimise plugging
Plugging is only needed with requests that also need a file, so hide
plugging under a ->needs_file check. Also, place ->needs_file and ->plug
bits into the same byte of io_op_defs, it may matter for compilers, e.g.
only with the change a tested one decided to optimise two memory testb
into a more with two register testb.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1600d1287bb7d16451d4ef3343252787a5314927.1633532552.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
54daa9b2d8 io_uring: correct fill events helpers types
CQE result is a 32-bit integer, so the functions generating CQEs are
better to accept not long but ints. Convert io_cqring_fill_event() and
other helpers.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7ca6f15255e9117eae28adcac272744cae29b113.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
eb6e6f0690 io_uring: inline io_poll_complete
Inline io_poll_complete(), it's simple and doesn't have any particular
purpose.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/933d7ee3e4450749a2d892235462c8f18d030293.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:55 -06:00
Pavel Begunkov
867f8fa5ae io_uring: inline io_req_needs_clean()
There is only a single user of io_req_needs_clean() inline it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6111d0221ef4b439cad401e135dd6a5f990a0501.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
d17e56eb49 io_uring: remove struct io_completion
We keep struct io_completion only as a temporal storage of cflags, Place
it in io_kiocb, it's cleaner, removes extra bits and even might be used
for future optimisations.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5299bd5c223204065464bd87a515d0e405316086.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
d886e185a1 io_uring: control ->async_data with a REQ_F flag
->async_data is a slow path, so it won't matter much if we do the clean
up inside io_clean_op(). Moreover, in many cases it's allocated together
with setting one or more of IO_REQ_CLEAN_FLAGS flags, so it'd go through
io_clean_op() anyway.

Control ->async_data allocation with a new flag REQ_F_ASYNC_DATA, so we
can do all the maintainence under io_req_needs_clean() fast check.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6892cf5883c459f36bda26f30ceb16742b20b84b.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
c1e53a6988 io_uring: optimise io_free_batch_list()
Delay reading the next node in io_free_batch_list(), allows the compiler
to load the value a bit later improving register spilling in some cases.
With gcc 11.1 it helped to move @task_refs variable from the stack to a
register and optimises out a couple of per request instructions.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/cc9fdfb6f72a4e8bc9918a5e9f2d97869a263ae4.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
c072481ded io_uring: mark cold functions
Attribute cold functions so compilers can optimise them for size. It
shrinks the binary by 2.5-3%

   text    data     bss     dec     hex filename
  90670   14002       8  104680   198e8 ./fs/io_uring.o
  88053   14002       8  102063   18eaf ./fs/io_uring.o

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b53d385f91dca45170b67d7f11c7abd787e821f6.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
37f0e767e1 io_uring: optimise ctx referencing by requests
Currenlty, we allocate one ctx reference per request at submission time
and put them at free. It's batched and not so expensive but it still
bloats the kernel, adds 2 function calls for rcu and adds some overhead
for request counting in io_free_batch_list().

Always keep one reference with a request, even when it's freed and in
io_uring request caches. There is extra work at ring exit / quiesce
paths, which now need to put all cached requests. io_ring_exit_work() is
already looping, so it's not a problem. Add hybrid-busy waiting to
io_ctx_quiesce() as well for now.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/99613fbe396e80777228cde39bbda1aa8938554e.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
d60aa65ba2 io_uring: merge CQ and poll waitqueues
->cq_wait and ->poll_wait and waken up in the same manner, use a single
waitqueue for both of them. CQ waiters are queued exclusively, so wake
up should first go over all pollers and that's what we need.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/00fe603e50000365774cf8435ef5fe03f049c1c9.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
aede728aae io_uring: don't wake sqpoll in io_cqring_ev_posted
io_cqring_ev_posted() doesn't need to wake SQPOLL, it's either done by
userspace or with task_work, but no action is required on request
completion. Rip off bits waking it up in io_cqring_ev_posted().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b49dab27b64cf11f4c50f2f90dcaac123430e05d.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
765ff496c7 io_uring: optimise INIT_WQ_LIST
The invariant of io_wq_work_list is that it's empty IFF ->first is NULL,
so no need to initially set ->last. With now having more users of the
list it may play a role, i.e. used in each tw iteration and on every
completion flushing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c464ab5cab6e46a858c6d39c107e92b3b5291f13.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00
Pavel Begunkov
a33ae9ce16 io_uring: optimise request allocation
Even after fully inlining io_alloc_req() my compiler does a NULL check
in the path of successful allocation, no hacks like an empty dereference
help it. Restructure io_alloc_req() by splitting out refilling part, so
the compiler generate a slightly better binary.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/eda17571bdc7248d8e617b23e7132a5416e4680b.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:49:54 -06:00