Commit Graph

282 Commits

Author SHA1 Message Date
Linus Torvalds 6e17c6de3d - Yosry Ahmed brought back some cgroup v1 stats in OOM logs.
- Yosry has also eliminated cgroup's atomic rstat flushing.
 
 - Nhat Pham adds the new cachestat() syscall.  It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability.
 
 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning.
 
 - Lorenzo Stoakes has done some maintanance work on the get_user_pages()
   interface.
 
 - Liam Howlett continues with cleanups and maintenance work to the maple
   tree code.  Peng Zhang also does some work on maple tree.
 
 - Johannes Weiner has done some cleanup work on the compaction code.
 
 - David Hildenbrand has contributed additional selftests for
   get_user_pages().
 
 - Thomas Gleixner has contributed some maintenance and optimization work
   for the vmalloc code.
 
 - Baolin Wang has provided some compaction cleanups,
 
 - SeongJae Park continues maintenance work on the DAMON code.
 
 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting.
 
 - Christoph Hellwig has some cleanups for the filemap/directio code.
 
 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the provided
   APIs rather than open-coding accesses.
 
 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings.
 
 - John Hubbard has a series of fixes to the MM selftesting code.
 
 - ZhangPeng continues the folio conversion campaign.
 
 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock.
 
 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from
   128 to 8.
 
 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management.
 
 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code.
 
 - Vishal Moola also has done some folio conversion work.
 
 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch.
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Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:

 - Yosry Ahmed brought back some cgroup v1 stats in OOM logs

 - Yosry has also eliminated cgroup's atomic rstat flushing

 - Nhat Pham adds the new cachestat() syscall. It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability

 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning

 - Lorenzo Stoakes has done some maintanance work on the
   get_user_pages() interface

 - Liam Howlett continues with cleanups and maintenance work to the
   maple tree code. Peng Zhang also does some work on maple tree

 - Johannes Weiner has done some cleanup work on the compaction code

 - David Hildenbrand has contributed additional selftests for
   get_user_pages()

 - Thomas Gleixner has contributed some maintenance and optimization
   work for the vmalloc code

 - Baolin Wang has provided some compaction cleanups,

 - SeongJae Park continues maintenance work on the DAMON code

 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting

 - Christoph Hellwig has some cleanups for the filemap/directio code

 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the
   provided APIs rather than open-coding accesses

 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings

 - John Hubbard has a series of fixes to the MM selftesting code

 - ZhangPeng continues the folio conversion campaign

 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock

 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
   from 128 to 8

 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management

 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code

 - Vishal Moola also has done some folio conversion work

 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
  mm/hugetlb: remove hugetlb_set_page_subpool()
  mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
  hugetlb: revert use of page_cache_next_miss()
  Revert "page cache: fix page_cache_next/prev_miss off by one"
  mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
  mm: memcg: rename and document global_reclaim()
  mm: kill [add|del]_page_to_lru_list()
  mm: compaction: convert to use a folio in isolate_migratepages_block()
  mm: zswap: fix double invalidate with exclusive loads
  mm: remove unnecessary pagevec includes
  mm: remove references to pagevec
  mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
  mm: remove struct pagevec
  net: convert sunrpc from pagevec to folio_batch
  i915: convert i915_gpu_error to use a folio_batch
  pagevec: rename fbatch_count()
  mm: remove check_move_unevictable_pages()
  drm: convert drm_gem_put_pages() to use a folio_batch
  i915: convert shmem_sg_free_table() to use a folio_batch
  scatterlist: add sg_set_folio()
  ...
2023-06-28 10:28:11 -07:00
Matthew Wilcox (Oracle) 76fa884290 net: convert sunrpc from pagevec to folio_batch
Remove the last usage of pagevecs.  There is a slight change here; we now
free the folio_batch as soon as it fills up instead of freeing the
folio_batch when we try to add a page to a full batch.  This should have
no effect in practice.

Link: https://lkml.kernel.org/r/20230621164557.3510324-10-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-23 16:59:30 -07:00
Chuck Lever 00a87e5d1d SUNRPC: Address RCU warning in net/sunrpc/svc.c
$ make C=1 W=1 net/sunrpc/svc.o
make[1]: Entering directory 'linux/obj/manet.1015granger.net'
  GEN     Makefile
  CALL    linux/server-development/scripts/checksyscalls.sh
  DESCEND objtool
  INSTALL libsubcmd_headers
  DESCEND bpf/resolve_btfids
  INSTALL libsubcmd_headers
  CC [M]  net/sunrpc/svc.o
  CHECK   linux/server-development/net/sunrpc/svc.c
linux/server-development/net/sunrpc/svc.c:1225:9: warning: incorrect type in argument 1 (different address spaces)
linux/server-development/net/sunrpc/svc.c:1225:9:    expected struct spinlock [usertype] *lock
linux/server-development/net/sunrpc/svc.c:1225:9:    got struct spinlock [noderef] __rcu *
linux/server-development/net/sunrpc/svc.c:1227:40: warning: incorrect type in argument 1 (different address spaces)
linux/server-development/net/sunrpc/svc.c:1227:40:    expected struct spinlock [usertype] *lock
linux/server-development/net/sunrpc/svc.c:1227:40:    got struct spinlock [noderef] __rcu *
make[1]: Leaving directory 'linux/obj/manet.1015granger.net'

Warning introduced by commit 913292c97d ("sched.h: Annotate
sighand_struct with __rcu").

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-06-17 13:18:07 -04:00
Azeem Shaikh a9156d7e7d SUNRPC: Use sysfs_emit in place of strlcpy/sprintf
Part of an effort to remove strlcpy() tree-wide [1].

Direct replacement is safe here since the getter in kernel_params_ops
handles -errno return [2].

[1] https://github.com/KSPP/linux/issues/89
[2] https://elixir.bootlin.com/linux/v6.4-rc6/source/include/linux/moduleparam.h#L52

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-06-17 13:18:07 -04:00
Chuck Lever 88e4d41a26 SUNRPC: Use __alloc_bulk_pages() in svc_init_buffer()
Clean up: Use the bulk page allocator when filling a server thread's
buffer page array.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-06-05 09:01:44 -04:00
Chuck Lever 07a2730593 SUNRPC: Fix trace_svc_register() call site
The trace event recorded incorrect values for the registered family,
protocol, and port because the arguments are in the wrong order.

Fixes: b4af59328c ("SUNRPC: Trace server-side rpcbind registration events")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-05-14 15:58:14 -04:00
Chuck Lever 29cd2927fb SUNRPC: Fix encoding of accepted but unsuccessful RPC replies
Jiri Slaby says:
> I bisected to this ... as it breaks nfs3-only servers in 6.3.
> I.e. /etc/nfs.conf containing:
> [nfsd]
> vers4=no
>
> The client sees:
>  mount("10.0.2.15:/tmp", "/mnt", "nfs", 0, "vers=4.2,addr=10.0.2.15,clientad"...) = -1 EIO (Input/output error)
>  write(2, "mount.nfs: mount system call fai"..., 45
>  mount.nfs: mount system call failed for /mnt
>
> And the kernel says:
>  nfs4_discover_server_trunking unhandled error -5. Exiting with error EIO

Reported-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://bugzilla.suse.com/show_bug.cgi?id=1210995
Fixes: 4bcf0343e8 ("SUNRPC: Set rq_accept_statp inside ->accept methods")
Tested-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-05-03 09:35:51 -04:00
Chuck Lever 6a0cdf56bf SUNRPC: Be even lazier about releasing pages
A single RPC transaction that touches only a couple of pages means
rq_pvec will not be even close to full in svc_xpt_release(). This is
a common case.

Instead, just leave the pages in rq_pvec until it is completely
full. This improves the efficiency of the batch release mechanism
on workloads that involve small RPC messages.

The rq_pvec is also fully emptied just before thread exit.

Reviewed-by: Calum Mackay <calum.mackay@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-04-27 18:49:23 -04:00
Chuck Lever 647a2a6428 SUNRPC: Convert svc_xprt_release() to the release_pages() API
Instead of invoking put_page() one-at-a-time, pass the "response"
portion of rq_pages directly to release_pages() to reduce the number
of times each nfsd thread invokes a page allocator API.

Since svc_xprt_release() is not invoked while a client is waiting
for an RPC Reply, this is not expected to directly impact mean
request latencies on a lightly or moderately loaded server. However
as workload intensity increases, I expect somewhat better
scalability: the same number of server threads should be able to
handle more work.

Reviewed-by: Calum Mackay <calum.mackay@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-04-26 09:05:02 -04:00
Chuck Lever b20cb39def SUNRPC: Relocate svc_free_res_pages()
Clean-up: There doesn't seem to be a reason why this function is
stuck in a header. One thing it prevents is the convenient addition
of tracing. Moving it to a source file also makes the rq_respages
clean-up logic easier to find.

Reviewed-by: Calum Mackay <calum.mackay@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-04-26 09:05:01 -04:00
Chuck Lever 55fcc7d915 SUNRPC: Ignore return value of ->xpo_sendto
Clean up: All callers of svc_process() ignore its return value, so
svc_process() can safely be converted to return void. Ditto for
svc_send().

The return value of ->xpo_sendto() is now used only as part of a
trace event.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-04-26 09:05:01 -04:00
Chuck Lever 0f5162480b NFSD: Watch for rq_pages bounds checking errors in nfsd_splice_actor()
There have been several bugs over the years where the NFSD splice
actor has attempted to write outside the rq_pages array.

This is a "should never happen" condition, but if for some reason
the pipe splice actor should attempt to walk past the end of
rq_pages, it needs to terminate the READ operation to prevent
corruption of the pointer addresses in the fields just beyond the
array.

A server crash is thus prevented. Since the code is not behaving,
the READ operation returns -EIO to the client. None of the READ
payload data can be trusted if the splice actor isn't operating as
expected.

Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2023-04-26 09:05:01 -04:00
Benjamin Coddington 9ca6705d9d SUNRPC: Fix a server shutdown leak
Fix a race where kthread_stop() may prevent the threadfn from ever getting
called.  If that happens the svc_rqst will not be cleaned up.

Fixes: ed6473ddc7 ("NFSv4: Fix callback server shutdown")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-03-08 08:46:41 -05:00
Chuck Lever ccf08bed6e SUNRPC: Replace pool stats with per-CPU variables
Eliminate the use of bus-locked operations in svc_xprt_enqueue(),
which is a hot path. Replace them with per-cpu variables to reduce
cross-CPU memory bus traffic.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:32 -05:00
Chuck Lever 65ba3d2425 SUNRPC: Use per-CPU counters to tally server RPC counts
- Improves counting accuracy
 - Reduces cross-CPU memory traffic

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:32 -05:00
Chuck Lever 4bcf0343e8 SUNRPC: Set rq_accept_statp inside ->accept methods
To navigate around the space that svcauth_gss_accept() reserves
for the RPC payload body length and sequence number fields,
svcauth_gss_release() does a little dance with the reply's
accept_stat, moving the accept_stat value in the response buffer
down by two words.

Instead, let's have the ->accept() methods each set the proper
final location of the accept_stat to avoid having to move
things.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:31 -05:00
Chuck Lever cee4db1945 SUNRPC: Refactor RPC server dispatch method
Currently, svcauth_gss_accept() pre-reserves response buffer space
for the RPC payload length and GSS sequence number before returning
to the dispatcher, which then adds the header's accept_stat field.

The problem is the accept_stat field is supposed to go before the
length and seq_num fields. So svcauth_gss_release() has to relocate
the accept_stat value (see svcauth_gss_prepare_to_wrap()).

To enable these fields to be added to the response buffer in the
correct (final) order, the pointer to the accept_stat has to be made
available to svcauth_gss_accept() so that it can set it before
reserving space for the length and seq_num fields.

As a first step, move the pointer to the location of the accept_stat
field into struct svc_rqst.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:31 -05:00
Chuck Lever 5f69d5f65a SUNRPC: Final clean-up of svc_process_common()
The @resv parameter is no longer used.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:31 -05:00
Chuck Lever 649a692e0f SUNRPC: Convert RPC Reply header encoding to use xdr_stream
The main part of RPC header encoding and the formation of error
responses are now done using the xdr_stream helpers. Bounds checking
before each XDR data item is encoded makes the server's encoding
path safer against accidental buffer overflows.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:30 -05:00
Chuck Lever fcef2afffe SUNRPC: Hoist init_encode out of svc_authenticate()
Now that each ->accept method has been converted, the
svcxdr_init_encode() calls can be hoisted back up into the generic
RPC server code.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:29 -05:00
Chuck Lever faca897816 SUNRPC: Move svcxdr_init_encode() into ->accept methods
Refactor: So that the overhaul of each ->accept method can be done
in separate smaller patches, temporarily move the
svcxdr_init_encode() call into those methods.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:28 -05:00
Chuck Lever 8dd41d70f3 SUNRPC: Push svcxdr_init_encode() into svc_process_common()
Now that all vs_dispatch functions invoke svcxdr_init_encode(), it
is common code and can be pushed down into the generic RPC server.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:27 -05:00
Chuck Lever 6d037b15e4 SUNRPC: Remove the rpc_stat variable in svc_process_common()
There's no RPC header field called rpc_stat; more precisely, the
variable appears to be recording an accept_stat value. But it looks
like we don't need to preserve this value at all, actually, so
simply remove the variable.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:25 -05:00
Chuck Lever f4afc8fead SUNRPC: Hoist svcxdr_init_decode() into svc_process()
Now the entire RPC Call header parsing path is handled via struct
xdr_stream-based decoders.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:21 -05:00
Chuck Lever 1c59a532ae SUNRPC: Remove svc_process_common's argv parameter
Clean up: With xdr_stream decoding, the @argv parameter is no longer
used.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:21 -05:00
Chuck Lever 163cdfca34 SUNRPC: Decode most of RPC header with xdr_stream
Done as part of hardening the server-side RPC header decoding path.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:21 -05:00
Chuck Lever 4119bd0306 SUNRPC: Eliminate unneeded variable
Clean up: Saving the RPC program number in two places is
unnecessary.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:19 -05:00
Chuck Lever 2009e32997 SUNRPC: Re-order construction of the first reply fields
Clean up: Group these together for legibility.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:19 -05:00
Chuck Lever 6898b47a0f SUNRPC: Hoist init_decode out of svc_authenticate()
Now that each ->accept method has been converted to use xdr_stream,
the svcxdr_init_decode() calls can be hoisted back up into the
generic RPC server code.

The dprintk in svc_authenticate() is removed, since
trace_svc_authenticate() reports the same information.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:19 -05:00
Chuck Lever 1e9e177df3 SUNRPC: Move svcxdr_init_decode() into ->accept methods
Refactor: So that the overhaul of each ->accept method can be done
in separate smaller patches, temporarily move the
svcxdr_init_decode() call into those methods.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:09 -05:00
Chuck Lever dba5eaa46b SUNRPC: Push svcxdr_init_decode() into svc_process_common()
Now that all vs_dispatch functions invoke svcxdr_init_decode(), it
is common code and can be pushed down into the generic RPC server.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:09 -05:00
Linus Torvalds 7dd4b804e0 nfsd-6.2 fixes:
- Fix a race when creating NFSv4 files
 - Revert the use of relaxed bitops
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Merge tag 'nfsd-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

 - Fix a race when creating NFSv4 files

 - Revert the use of relaxed bitops

* tag 'nfsd-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Use set_bit(RQ_DROPME)
  Revert "SUNRPC: Use RMW bitops in single-threaded hot paths"
  nfsd: fix handling of cached open files in nfsd4_open codepath
2023-01-10 15:03:06 -06:00
Chuck Lever 7827c81f02 Revert "SUNRPC: Use RMW bitops in single-threaded hot paths"
The premise that "Once an svc thread is scheduled and executing an
RPC, no other processes will touch svc_rqst::rq_flags" is false.
svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd
threads when determining which thread to wake up next.

Found via KCSAN.

Fixes: 28df098881 ("SUNRPC: Use RMW bitops in single-threaded hot paths")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-06 13:17:12 -05:00
Steven Rostedt (Google) 292a089d78 treewide: Convert del_timer*() to timer_shutdown*()
Due to several bugs caused by timers being re-armed after they are
shutdown and just before they are freed, a new state of timers was added
called "shutdown".  After a timer is set to this state, then it can no
longer be re-armed.

The following script was run to find all the trivial locations where
del_timer() or del_timer_sync() is called in the same function that the
object holding the timer is freed.  It also ignores any locations where
the timer->function is modified between the del_timer*() and the free(),
as that is not considered a "trivial" case.

This was created by using a coccinelle script and the following
commands:

    $ cat timer.cocci
    @@
    expression ptr, slab;
    identifier timer, rfield;
    @@
    (
    -       del_timer(&ptr->timer);
    +       timer_shutdown(&ptr->timer);
    |
    -       del_timer_sync(&ptr->timer);
    +       timer_shutdown_sync(&ptr->timer);
    )
      ... when strict
          when != ptr->timer
    (
            kfree_rcu(ptr, rfield);
    |
            kmem_cache_free(slab, ptr);
    |
            kfree(ptr);
    )

    $ spatch timer.cocci . > /tmp/t.patch
    $ patch -p1 < /tmp/t.patch

Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ]
Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ]
Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-25 13:38:09 -08:00
Chuck Lever c65d9df0c4 SUNRPC: Make the svc_authenticate tracepoint conditional
Clean up: Simplify the tracepoint's only call site.

Also, I noticed that when svc_authenticate() returns SVC_COMPLETE,
it leaves rq_auth_stat set to an error value. That doesn't need to
be recorded in the trace log.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-12-10 11:01:13 -05:00
Chuck Lever 5a717a6e01 SUNRPC: Remove unused svc_rqst::rq_lock field
Clean up after commit 22700f3c6d ("SUNRPC: Improve ordering of
transport processing").

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-28 12:54:44 -05:00
Chuck Lever f18d8afbf2 SUNRPC: Clarify comment that documents svc_max_payload()
Note the function returns a per-transport value, not a per-request
value (eg, one that is related to the size of the available send or
receive buffer space).

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26 14:02:43 -04:00
Chuck Lever 103cc1fafe SUNRPC: Parametrize how much of argsize should be zeroed
Currently, SUNRPC clears the whole of .pc_argsize before processing
each incoming RPC transaction. Add an extra parameter to struct
svc_procedure to enable upper layers to reduce the amount of each
operation's argument structure that is zeroed by SUNRPC.

The size of struct nfsd4_compoundargs, in particular, is a lot to
clear on each incoming RPC Call. A subsequent patch will cut this
down to something closer to what NFSv2 and NFSv3 uses.

This patch should cause no behavior changes.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26 14:02:42 -04:00
Chuck Lever 81593c4dff SUNRPC: Optimize svc_process()
Move exception handling code out of the hot path, and avoid the need
for a bswap of a non-constant.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26 14:02:42 -04:00
Chuck Lever 28df098881 SUNRPC: Use RMW bitops in single-threaded hot paths
I noticed CPU pipeline stalls while using perf.

Once an svc thread is scheduled and executing an RPC, no other
processes will touch svc_rqst::rq_flags. Thus bus-locked atomics are
not needed outside the svc thread scheduler.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-23 11:06:29 -04:00
Chuck Lever 2059b698a2 SUNRPC: Simplify synopsis of svc_pool_for_cpu()
Clean up: There is one caller. The @cpu argument can be made
implicit now that a get_cpu/put_cpu pair is no longer needed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-19 12:25:40 -04:00
Chuck Lever 37902c6313 NFSD: Move svc_serv_ops::svo_function into struct svc_serv
Hoist svo_function back into svc_serv and remove struct
svc_serv_ops, since the struct is now devoid of fields.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever f49169c97f NFSD: Remove svc_serv_ops::svo_module
struct svc_serv_ops is about to be removed.

Neil Brown says:
> I suspect svo_module can go as well - I don't think the thread is
> ever the thing that primarily keeps a module active.

A random sample of kthread_create() callers shows sunrpc is the only
one that manages module reference count in this way.

Suggested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever c7d7ec8f04 SUNRPC: Remove svc_shutdown_net()
Clean up: svc_shutdown_net() now does nothing but call
svc_close_net(). Replace all external call sites.

svc_close_net() is renamed to be the inverse of svc_xprt_create().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever 4355d767a2 SUNRPC: Rename svc_close_xprt()
Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever 87cdd8641c SUNRPC: Remove svo_shutdown method
Clean up. Neil observed that "any code that calls svc_shutdown_net()
knows what the shutdown function should be, and so can call it
directly."

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-02-28 10:26:39 -05:00
NeilBrown 6b044fbaab lockd: use svc_set_num_threads() for thread start and stop
svc_set_num_threads() does everything that lockd_start_svc() does, except
set sv_maxconn.  It also (when passed 0) finds the threads and
stops them with kthread_stop().

So move the setting for sv_maxconn, and use svc_set_num_thread()

We now don't need nlmsvc_task.

Now that we use svc_set_num_threads() it makes sense to set svo_module.
This request that the thread exists with module_put_and_exit().
Also fix the documentation for svo_module to make this explicit.

svc_prepare_thread is now only used where it is defined, so it can be
made static.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-12-13 13:42:58 -05:00
NeilBrown 93aa619eb0 SUNRPC: always treat sv_nrpools==1 as "not pooled"
Currently 'pooled' services hold a reference on the pool_map, and
'unpooled' services do not.
svc_destroy() uses the presence of ->svo_function (via
svc_serv_is_pooled()) to determine if the reference should be dropped.
There is no direct correlation between being pooled and the use of
svo_function, though in practice, lockd is the only non-pooled service,
and the only one not to use svo_function.

This is untidy and would cause problems if we changed lockd to use
svc_set_num_threads(), which requires the use of ->svo_function.

So change the test for "is the service pooled" to "is sv_nrpools > 1".

This means that when svc_pool_map_get() returns 1, it must NOT take a
reference to the pool.

We discard svc_serv_is_pooled(), and test sv_nrpools directly.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-12-13 13:42:57 -05:00
NeilBrown cf0e124e0a SUNRPC: move the pool_map definitions (back) into svc.c
These definitions are not used outside of svc.c, and there is no
evidence that they ever have been.  So move them into svc.c
and make the declarations 'static'.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-12-13 13:42:57 -05:00
NeilBrown 3ebdbe5203 SUNRPC: discard svo_setup and rename svc_set_num_threads_sync()
The ->svo_setup callback serves no purpose.  It is always called from
within the same module that chooses which callback is needed.  So
discard it and call the relevant function directly.

Now that svc_set_num_threads() is no longer used remove it and rename
svc_set_num_threads_sync() to remove the "_sync" suffix.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-12-13 13:42:53 -05:00