1. 28 11月, 2017 1 次提交
  2. 09 2月, 2017 4 次提交
  3. 01 2月, 2017 1 次提交
  4. 14 1月, 2017 1 次提交
    • P
      locking/atomic, kref: Add kref_read() · 2c935bc5
      Peter Zijlstra 提交于
      Since we need to change the implementation, stop exposing internals.
      
      Provide kref_read() to read the current reference count; typically
      used for debug messages.
      
      Kills two anti-patterns:
      
      	atomic_read(&kref->refcount)
      	kref->refcount.counter
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      2c935bc5
  5. 25 12月, 2016 1 次提交
  6. 28 9月, 2016 1 次提交
    • K
      sunrpc: queue work on system_power_efficient_wq · 77b00bc0
      Ke Wang 提交于
      sunrpc uses workqueue to clean cache regulary. There is no real dependency
      of executing work on the cpu which queueing it.
      
      On a idle system, especially for a heterogeneous systems like big.LITTLE,
      it is observed that the big idle cpu was woke up many times just to service
      this work, which against the principle of power saving. It would be better
      if we can schedule it on a cpu which the scheduler believes to be the most
      appropriate one.
      
      After apply this patch, system_wq will be replaced by
      system_power_efficient_wq for sunrpc. This functionality is enabled when
      CONFIG_WQ_POWER_EFFICIENT is selected.
      Signed-off-by: NKe Wang <ke.wang@spreadtrum.com>
      Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
      77b00bc0
  7. 14 7月, 2016 1 次提交
  8. 05 4月, 2016 1 次提交
    • K
      mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros · 09cbfeaf
      Kirill A. Shutemov 提交于
      PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
      ago with promise that one day it will be possible to implement page
      cache with bigger chunks than PAGE_SIZE.
      
      This promise never materialized.  And unlikely will.
      
      We have many places where PAGE_CACHE_SIZE assumed to be equal to
      PAGE_SIZE.  And it's constant source of confusion on whether
      PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
      especially on the border between fs and mm.
      
      Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
      breakage to be doable.
      
      Let's stop pretending that pages in page cache are special.  They are
      not.
      
      The changes are pretty straight-forward:
      
       - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
      
       - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
      
       - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
      
       - page_cache_get() -> get_page();
      
       - page_cache_release() -> put_page();
      
      This patch contains automated changes generated with coccinelle using
      script below.  For some reason, coccinelle doesn't patch header files.
      I've called spatch for them manually.
      
      The only adjustment after coccinelle is revert of changes to
      PAGE_CAHCE_ALIGN definition: we are going to drop it later.
      
      There are few places in the code where coccinelle didn't reach.  I'll
      fix them manually in a separate patch.  Comments and documentation also
      will be addressed with the separate patch.
      
      virtual patch
      
      @@
      expression E;
      @@
      - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
      + E
      
      @@
      expression E;
      @@
      - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
      + E
      
      @@
      @@
      - PAGE_CACHE_SHIFT
      + PAGE_SHIFT
      
      @@
      @@
      - PAGE_CACHE_SIZE
      + PAGE_SIZE
      
      @@
      @@
      - PAGE_CACHE_MASK
      + PAGE_MASK
      
      @@
      expression E;
      @@
      - PAGE_CACHE_ALIGN(E)
      + PAGE_ALIGN(E)
      
      @@
      expression E;
      @@
      - page_cache_get(E)
      + get_page(E)
      
      @@
      expression E;
      @@
      - page_cache_release(E)
      + put_page(E)
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      09cbfeaf
  9. 18 3月, 2016 1 次提交
  10. 24 2月, 2016 1 次提交
    • S
      sunrpc/cache: fix off-by-one in qword_get() · b7052cd7
      Stefan Hajnoczi 提交于
      The qword_get() function NUL-terminates its output buffer.  If the input
      string is in hex format \xXXXX... and the same length as the output
      buffer, there is an off-by-one:
      
        int qword_get(char **bpp, char *dest, int bufsize)
        {
            ...
            while (len < bufsize) {
                ...
                *dest++ = (h << 4) | l;
                len++;
            }
            ...
            *dest = '\0';
            return len;
        }
      
      This patch ensures the NUL terminator doesn't fall outside the output
      buffer.
      Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      b7052cd7
  11. 23 1月, 2016 1 次提交
    • A
      wrappers for ->i_mutex access · 5955102c
      Al Viro 提交于
      parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
      inode_foo(inode) being mutex_foo(&inode->i_mutex).
      
      Please, use those for access to ->i_mutex; over the coming cycle
      ->i_mutex will become rwsem, with ->lookup() done with it held
      only shared.
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      5955102c
  12. 24 10月, 2015 1 次提交
    • N
      sunrpc/cache: make cache flushing more reliable. · 77862036
      Neil Brown 提交于
      The caches used to store sunrpc authentication information can be
      flushed by writing a timestamp to a file in /proc.
      
      This timestamp has a one-second resolution and any entry in cache that
      was last_refreshed *before* that time is treated as expired.
      
      This is problematic as it is not possible to reliably flush the cache
      without interrupting NFS service.
      If the current time is written to the "flush" file, any entry that was
      added since the current second started will still be treated as valid.
      If one second beyond than the current time is written to the file
      then no entries can be valid until the second ticks over.  This will
      mean that no NFS request will be handled for up to 1 second.
      
      To resolve this issue we make two changes:
      
      1/ treat an entry as expired if the timestamp when it was last_refreshed
        is before *or the same as* the expiry time.  This means that current
        code which writes out the current time will now flush the cache
        reliably.
      
      2/ when a new entry in added to the cache -  set the last_refresh timestamp
        to 1 second *beyond* the current flush time, when that not in the
        past.
        This ensures that newly added entries will always be valid.
      
      Now that we have a very reliable way to flush the cache, and also
      since we are using "since-boot" timestamps which are monotonic,
      change cache_purge() to set the smallest future flush_time which
      will work, and leave it there: don't revert to '1'.
      
      Also disable the setting of the 'flush_time' far into the future.
      That has never been useful and is now awkward as it would cause
      last_refresh times to be strange.
      Finally: if a request is made to set the 'flush_time' to the current
      second, assume the intent is to flush the cache and advance it, if
      necessary, to 1 second beyond the current 'flush_time' so that all
      active entries will be deemed to be expired.
      
      As part of this we need to add a 'cache_detail' arg to cache_init()
      and cache_fresh_locked() so they can find the current ->flush_time.
      Signed-off-by: NNeilBrown <neilb@suse.com>
      Reported-by: NOlaf Kirch <okir@suse.com>
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      77862036
  13. 13 8月, 2015 3 次提交
  14. 16 4月, 2015 1 次提交
    • R
      lib/string_helpers.c: change semantics of string_escape_mem · 41416f23
      Rasmus Villemoes 提交于
      The current semantics of string_escape_mem are inadequate for one of its
      current users, vsnprintf().  If that is to honour its contract, it must
      know how much space would be needed for the entire escaped buffer, and
      string_escape_mem provides no way of obtaining that (short of allocating a
      large enough buffer (~4 times input string) to let it play with, and
      that's definitely a big no-no inside vsnprintf).
      
      So change the semantics for string_escape_mem to be more snprintf-like:
      Return the size of the output that would be generated if the destination
      buffer was big enough, but of course still only write to the part of dst
      it is allowed to, and (contrary to snprintf) don't do '\0'-termination.
      It is then up to the caller to detect whether output was truncated and to
      append a '\0' if desired.  Also, we must output partial escape sequences,
      otherwise a call such as snprintf(buf, 3, "%1pE", "\123") would cause
      printf to write a \0 to buf[2] but leaving buf[0] and buf[1] with whatever
      they previously contained.
      
      This also fixes a bug in the escaped_string() helper function, which used
      to unconditionally pass a length of "end-buf" to string_escape_mem();
      since the latter doesn't check osz for being insanely large, it would
      happily write to dst.  For example, kasprintf(GFP_KERNEL, "something and
      then %pE", ...); is an easy way to trigger an oops.
      
      In test-string_helpers.c, the -ENOMEM test is replaced with testing for
      getting the expected return value even if the buffer is too small.  We
      also ensure that nothing is written (by relying on a NULL pointer deref)
      if the output size is 0 by passing NULL - this has to work for
      kasprintf("%pE") to work.
      
      In net/sunrpc/cache.c, I think qword_add still has the same semantics.
      Someone should definitely double-check this.
      
      In fs/proc/array.c, I made the minimum possible change, but longer-term it
      should stop poking around in seq_file internals.
      
      [andriy.shevchenko@linux.intel.com: simplify qword_add]
      [andriy.shevchenko@linux.intel.com: add missed curly braces]
      Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
      Acked-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
      Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      41416f23
  15. 09 3月, 2015 1 次提交
  16. 10 12月, 2014 1 次提交
  17. 09 5月, 2014 1 次提交
  18. 15 1月, 2014 1 次提交
  19. 13 12月, 2013 1 次提交
  20. 14 7月, 2013 1 次提交
  21. 02 7月, 2013 5 次提交
    • N
      sunrpc: Don't schedule an upcall on a replaced cache entry. · 0bebc633
      NeilBrown 提交于
      When a cache entry is replaced, the "expiry_time" get set to
      zero by a call to "cache_fresh_locked(..., 0)" at the end of
      "sunrpc_cache_update".
      
      This low expiry time makes cache_check() think that the 'refresh_age'
      is negative, so the 'age' is comparatively large and a refresh is
      triggered.
      However refreshing a replaced entry it pointless, it cannot achieve
      anything useful.
      
      So teach cache_check to ignore a low refresh_age when expiry_time
      is zero.
      Reported-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      0bebc633
    • N
      net/sunrpc: xpt_auth_cache should be ignored when expired. · 7715cde8
      NeilBrown 提交于
      commit d202cce8
          sunrpc: never return expired entries in sunrpc_cache_lookup
      
      moved the 'entry is expired' test from cache_check to
      sunrpc_cache_lookup, so that it happened early and some races could
      safely be ignored.
      
      However the ip_map (in svcauth_unix.c) has a separate single-item
      cache which allows quick lookup without locking.  An entry in this
      case would not be subject to the expiry test and so could be used
      well after it has expired.
      
      This is not normally a big problem because the first time it is used
      after it is expired an up-call will be scheduled to refresh the entry
      (if it hasn't been scheduled already) and the old entry will then
      be invalidated.  So on the second attempt to use it after it has
      expired, ip_map_cached_get will discard it.
      
      However that is subtle and not ideal, so replace the "!cache_valid"
      test with "cache_is_expired".
      In doing this we drop the test on the "CACHE_VALID" bit.  This is
      unnecessary as the bit is never cleared, and an entry will only
      be cached if the bit is set.
      Reported-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      7715cde8
    • N
      sunrpc/cache: ensure items removed from cache do not have pending upcalls. · 013920eb
      NeilBrown 提交于
      It is possible for a race to set CACHE_PENDING after cache_clean()
      has removed a cache entry from the cache.
      If CACHE_PENDING is still set when the entry is finally 'put',
      the cache_dequeue() will never happen and we can leak memory.
      
      So set a new flag 'CACHE_CLEANED' when we remove something from
      the cache, and don't queue any upcall if it is set.
      
      If CACHE_PENDING is set before CACHE_CLEANED, the call that
      cache_clean() makes to cache_fresh_unlocked() will free memory
      as needed.  If CACHE_PENDING is set after CACHE_CLEANED, the
      test in sunrpc_cache_pipe_upcall will ensure that the memory
      is not allocated.
      
      Reported-by: <bstroesser@ts.fujitsu.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      013920eb
    • N
      sunrpc/cache: use cache_fresh_unlocked consistently and correctly. · 2a1c7f53
      NeilBrown 提交于
      cache_fresh_unlocked() is called when a cache entry
      has been updated and ensures that if there were any
      pending upcalls, they are cleared.
      
      So every time we update a cache entry, we should call this,
      and this should be the only way that we try to clear
      pending calls (that sort of uniformity makes code sooo much
      easier to read).
      
      try_to_negate_entry() will (possibly) mark an entry as
      negative.  If it doesn't, it is because the entry already
      is VALID.
      So the entry will be valid on exit, so it is appropriate to
      call cache_fresh_unlocked().
      So tidy up try_to_negate_entry() to do that, and remove
      partial open-coded cache_fresh_unlocked() from the one
      call-site of try_to_negate_entry().
      
      In the other branch of the 'switch(cache_make_upcall())',
      we again have a partial open-coded version of cache_fresh_unlocked().
      Replace that with a real call.
      
      And again in cache_clean(), use a real call to cache_fresh_unlocked().
      
      These call sites might previously have called
      cache_revisit_request() if CACHE_PENDING wasn't set.
      This is never necessary because cache_revisit_request() can
      only do anything if the item is in the cache_defer_hash,
      However any time that an item is added to the cache_defer_hash
      (setup_deferral), the code immediately tests CACHE_PENDING,
      and removes the entry again if it is clear.  So all other
      places we only need to 'cache_revisit_request' if we've
      just cleared CACHE_PENDING.
      Reported-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
      Signed-off-by: NNeilBrown  <neilb@suse.de>
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      2a1c7f53
    • N
      sunrpc/cache: remove races with queuing an upcall. · f9e1aedc
      NeilBrown 提交于
      We currently queue an upcall after setting CACHE_PENDING,
      and dequeue after clearing CACHE_PENDING.
      So a request should only be present when CACHE_PENDING is set.
      
      However we don't combine the test and the enqueue/dequeue in
      a protected region, so it is possible (if unlikely) for a race
      to result in a request being queued without CACHE_PENDING set,
      or a request to be absent despite CACHE_PENDING.
      
      So: include a test for CACHE_PENDING inside the regions of
      enqueue and dequeue where queue_lock is held, and abort
      the operation if the value is not as expected.
      
      Also remove the early 'return' from cache_dequeue() to ensure that it
      always removes all entries: As there is no locking between setting
      CACHE_PENDING and calling sunrpc_cache_pipe_upcall it is not
      inconceivable for some other thread to clear CACHE_PENDING and then
      someone else to set it and call sunrpc_cache_pipe_upcall, both before
      the original threads completed the call.
      
      With this, it perfectly safe and correct to:
       - call cache_dequeue() if and only if we have just
         cleared CACHE_PENDING
       - call sunrpc_cache_pipe_upcall() (via cache_make_upcall)
         if and only if we have just set CACHE_PENDING.
      Reported-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      Signed-off-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      f9e1aedc
  22. 21 5月, 2013 1 次提交
  23. 30 4月, 2013 1 次提交
  24. 10 4月, 2013 1 次提交
    • A
      procfs: new helper - PDE_DATA(inode) · d9dda78b
      Al Viro 提交于
      The only part of proc_dir_entry the code outside of fs/proc
      really cares about is PDE(inode)->data.  Provide a helper
      for that; static inline for now, eventually will be moved
      to fs/proc, along with the knowledge of struct proc_dir_entry
      layout.
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      d9dda78b
  25. 04 4月, 2013 1 次提交
  26. 28 2月, 2013 1 次提交
    • S
      hlist: drop the node parameter from iterators · b67bfe0d
      Sasha Levin 提交于
      I'm not sure why, but the hlist for each entry iterators were conceived
      
              list_for_each_entry(pos, head, member)
      
      The hlist ones were greedy and wanted an extra parameter:
      
              hlist_for_each_entry(tpos, pos, head, member)
      
      Why did they need an extra pos parameter? I'm not quite sure. Not only
      they don't really need it, it also prevents the iterator from looking
      exactly like the list iterator, which is unfortunate.
      
      Besides the semantic patch, there was some manual work required:
      
       - Fix up the actual hlist iterators in linux/list.h
       - Fix up the declaration of other iterators based on the hlist ones.
       - A very small amount of places were using the 'node' parameter, this
       was modified to use 'obj->member' instead.
       - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
       properly, so those had to be fixed up manually.
      
      The semantic patch which is mostly the work of Peter Senna Tschudin is here:
      
      @@
      iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
      
      type T;
      expression a,c,d,e;
      identifier b;
      statement S;
      @@
      
      -T b;
          <+... when != b
      (
      hlist_for_each_entry(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_continue(a,
      - b,
      c) S
      |
      hlist_for_each_entry_from(a,
      - b,
      c) S
      |
      hlist_for_each_entry_rcu(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_rcu_bh(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_continue_rcu_bh(a,
      - b,
      c) S
      |
      for_each_busy_worker(a, c,
      - b,
      d) S
      |
      ax25_uid_for_each(a,
      - b,
      c) S
      |
      ax25_for_each(a,
      - b,
      c) S
      |
      inet_bind_bucket_for_each(a,
      - b,
      c) S
      |
      sctp_for_each_hentry(a,
      - b,
      c) S
      |
      sk_for_each(a,
      - b,
      c) S
      |
      sk_for_each_rcu(a,
      - b,
      c) S
      |
      sk_for_each_from
      -(a, b)
      +(a)
      S
      + sk_for_each_from(a) S
      |
      sk_for_each_safe(a,
      - b,
      c, d) S
      |
      sk_for_each_bound(a,
      - b,
      c) S
      |
      hlist_for_each_entry_safe(a,
      - b,
      c, d, e) S
      |
      hlist_for_each_entry_continue_rcu(a,
      - b,
      c) S
      |
      nr_neigh_for_each(a,
      - b,
      c) S
      |
      nr_neigh_for_each_safe(a,
      - b,
      c, d) S
      |
      nr_node_for_each(a,
      - b,
      c) S
      |
      nr_node_for_each_safe(a,
      - b,
      c, d) S
      |
      - for_each_gfn_sp(a, c, d, b) S
      + for_each_gfn_sp(a, c, d) S
      |
      - for_each_gfn_indirect_valid_sp(a, c, d, b) S
      + for_each_gfn_indirect_valid_sp(a, c, d) S
      |
      for_each_host(a,
      - b,
      c) S
      |
      for_each_host_safe(a,
      - b,
      c, d) S
      |
      for_each_mesh_entry(a,
      - b,
      c, d) S
      )
          ...+>
      
      [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
      [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
      [akpm@linux-foundation.org: checkpatch fixes]
      [akpm@linux-foundation.org: fix warnings]
      [akpm@linux-foudnation.org: redo intrusive kvm changes]
      Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
      Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
      Cc: Wu Fengguang <fengguang.wu@intel.com>
      Cc: Marcelo Tosatti <mtosatti@redhat.com>
      Cc: Gleb Natapov <gleb@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b67bfe0d
  27. 23 2月, 2013 1 次提交
  28. 15 2月, 2013 3 次提交
  29. 24 1月, 2013 1 次提交