linux-toradex.git/kernel/padata.c, branch v4.11-rc1

padata: Remove unused but set variables

2016-10-25T03:08:10+00:00

Remove the unused but set variable pinst in padata_parallel_worker to
fix the following warning when building with 'W=1':

  kernel/padata.c: In function ‘padata_parallel_worker’:
  kernel/padata.c:68:26: warning: variable ‘pinst’ set but not used [-Wunused-but-set-variable]

Also remove the now unused variable pd which is only used to set pinst.

Signed-off-by: Tobias Klauser 
Acked-by: Steffen Klassert 
Signed-off-by: Herbert Xu

padata: Convert to hotplug state machine

2016-09-19T19:44:30+00:00

Install the callbacks via the state machine. CPU-hotplug multinstance support
is used with the nocalls() version. Maybe parts of padata_alloc() could be
moved into the online callback so that we could invoke ->startup callback for
instance and drop get_online_cpus().

Signed-off-by: Sebastian Andrzej Siewior 
Cc: Steffen Klassert 
Cc: Peter Zijlstra 
Cc: linux-crypto@vger.kernel.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160906170457.32393-14-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner

kernel/padata.c: hide unused functions

2016-05-20T02:12:14+00:00

A recent cleanup removed some exported functions that were not used
anywhere, which in turn exposed the fact that some other functions in
the same file are only used in some configurations.

We now get a warning about them when CONFIG_HOTPLUG_CPU is disabled:

  kernel/padata.c:670:12: error: '__padata_remove_cpu' defined but not used [-Werror=unused-function]
   static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
              ^~~~~~~~~~~~~~~~~~~
  kernel/padata.c:650:12: error: '__padata_add_cpu' defined but not used [-Werror=unused-function]
   static int __padata_add_cpu(struct padata_instance *pinst, int cpu)

This rearranges the code so the __padata_remove_cpu/__padata_add_cpu
functions are within the #ifdef that protects the code that calls them.

[akpm@linux-foundation.org: coding-style fixes]
Fixes: 4ba6d78c671e ("kernel/padata.c: removed unused code")
Signed-off-by: Arnd Bergmann 
Cc: Richard Cochran 
Cc: Steffen Klassert 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kernel/padata.c: removed unused code

2016-05-20T02:12:14+00:00

By accident I stumbled across code that has never been used.  This
driver has EXPORT_SYMBOL functions, and the only user of the code is
pcrypt.c, but this only uses a subset of the exported symbols.

According to 'git log -G', the functions, padata_set_cpumasks,
padata_add_cpu, and padata_remove_cpu have never been used since they
were first introduced.  This patch removes the unused code.

On one 64 bit build, with CRYPTO_PCRYPT built in, the text is more than
4k smaller.

  kbuild_hp> size $KBUILD_OUTPUT/vmlinux
      text    data     bss      dec hex    filename
  10566658 4678360 1122304 16367322 f9beda vmlinux
  10561984 4678360 1122304 16362648 f9ac98 vmlinux

On another config, 32 bit, the saving is about 0.5k bytes.

  kbuild_hp-x86> size $KBUILD_OUTPUT/vmlinux
  6012005 2409513 2785280 11206798 ab008e vmlinux
  6011491 2409513 2785280 11206284 aafe8c vmlinux

Signed-off-by: Richard Cochran 
Cc: Steffen Klassert 
Cc: Herbert Xu 
Cc: "David S. Miller" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

padata: use %*pb[l] to print bitmaps including cpumasks and nodemasks

2015-02-14T05:21:38+00:00

printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

Signed-off-by: Tejun Heo 
Cc: Steffen Klassert 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

padata: Fix wrong usage of rcu_dereference()

2013-12-05T13:28:42+00:00

A kernel with enabled lockdep complains about the wrong usage of
rcu_dereference() under a rcu_read_lock_bh() protected region.

  ===============================
  [ INFO: suspicious RCU usage. ]
  3.13.0-rc1+ #126 Not tainted
  -------------------------------
  linux/kernel/padata.c:115 suspicious rcu_dereference_check() usage!

  other info that might help us debug this:

  rcu_scheduler_active = 1, debug_locks = 1
  1 lock held by cryptomgr_test/153:
   #0:  (rcu_read_lock_bh){.+....}, at: [] padata_do_parallel+0x5/0x270

Fix that by using rcu_dereference_bh() instead.

Signed-off-by: Mathias Krause 
Acked-by: Steffen Klassert 
Signed-off-by: Herbert Xu

padata: make the sequence counter an atomic_t

2013-10-30T04:02:58+00:00

Using a spinlock to atomically increase a counter sounds wrong -- we've
atomic_t for this!

Also move 'seq_nr' to a different cache line than 'lock' to reduce cache
line trashing. This has the nice side effect of decreasing the size of
struct parallel_data from 192 to 128 bytes for a x86-64 build, e.g.
occupying only two instead of three cache lines.

Those changes results in a 5% performance increase on an IPsec test run
using pcrypt.

Btw. the seq_lock spinlock was never explicitly initialized -- one more
reason to get rid of it.

Signed-off-by: Mathias Krause 
Acked-by: Steffen Klassert 
Signed-off-by: Herbert Xu

padata - Register hotcpu notifier after initialization

2013-08-29T04:37:59+00:00

padata_cpu_callback() takes pinst->lock, to avoid taking
an uninitialized lock, register the notifier after it's
initialization.

Signed-off-by: Richard Weinberger 
Acked-by: Steffen Klassert 
Signed-off-by: Herbert Xu

padata - share code between CPU_ONLINE and CPU_DOWN_FAILED, same to CPU_DOWN_PREPARE and CPU_UP_CANCELED

2013-08-29T04:37:59+00:00

Share code between CPU_ONLINE and CPU_DOWN_FAILED, same to
CPU_DOWN_PREPARE and CPU_UP_CANCELED.

It will fix 2 bugs:

  "not check the return value of __padata_remove_cpu() and __padata_add_cpu()".
  "need add 'break' between CPU_UP_CANCELED and CPU_DOWN_FAILED".

Signed-off-by: Chen Gang 
Acked-by: Steffen Klassert 
Signed-off-by: Herbert Xu

padata: use __this_cpu_read per-cpu helper

2012-12-06T09:16:23+00:00

For bottom halves off, __this_cpu_read is better.

Signed-off-by: Shan Wei 
Reviewed-by: Christoph Lameter 
Acked-by: Steffen Klassert 
Signed-off-by: Herbert Xu