linux-toradex.git/include/linux/signal.h, branch v3.3.5

signal: add block_sigmask() for adding sigmask to current->blocked

2012-01-11T00:30:54+00:00

Abstract the code sequence for adding a signal handler's sa_mask to
current->blocked because the sequence is identical for all architectures.
Furthermore, in the past some architectures actually got this code wrong,
so introduce a wrapper that all architectures can use.

Signed-off-by: Matt Fleming 
Signed-off-by: Oleg Nesterov 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: H. Peter Anvin 
Cc: Tejun Heo 
Cc: "David S. Miller" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc

2011-05-20T20:33:21+00:00

* 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc: (41 commits)
  signal: trivial, fix the "timespec declared inside parameter list" warning
  job control: reorganize wait_task_stopped()
  ptrace: fix signal->wait_chldexit usage in task_clear_group_stop_trapping()
  signal: sys_sigprocmask() needs retarget_shared_pending()
  signal: cleanup sys_sigprocmask()
  signal: rename signandsets() to sigandnsets()
  signal: do_sigtimedwait() needs retarget_shared_pending()
  signal: introduce do_sigtimedwait() to factor out compat/native code
  signal: sys_rt_sigtimedwait: simplify the timeout logic
  signal: cleanup sys_rt_sigprocmask()
  x86: signal: sys_rt_sigreturn() should use set_current_blocked()
  x86: signal: handle_signal() should use set_current_blocked()
  signal: sigprocmask() should do retarget_shared_pending()
  signal: sigprocmask: narrow the scope of ->siglock
  signal: retarget_shared_pending: optimize while_each_thread() loop
  signal: retarget_shared_pending: consider shared/unblocked signals only
  signal: introduce retarget_shared_pending()
  ptrace: ptrace_check_attach() should not do s/STOPPED/TRACED/
  signal: Turn SIGNAL_STOP_DEQUEUED into GROUP_STOP_DEQUEUED
  signal: do_signal_stop: Remove the unneeded task_clear_group_stop_pending()
  ...

signal.h need a definition of struct task_struct

2011-05-20T01:22:20+00:00

This fixes these build errors on powerpc:

  In file included from arch/powerpc/mm/fault.c:18:
  include/linux/signal.h:239: error: 'struct task_struct' declared inside parameter list
  include/linux/signal.h:239: error: its scope is only this definition or declaration, which is probably not what you want
  include/linux/signal.h:240: error: 'struct task_struct' declared inside parameter list
  ..

Exposed by commit e66eed651fd1 ("list: remove prefetching from regular
list iterators"), which removed the include of  from
.

Without that, linux/signal.h no longer accidentally got the declaration
of 'struct task_struct'.

Fix by properly declaring the struct, rather than introducing any new
header file dependency.

Signed-off-by: Stephen Rothwell 
Signed-off-by: Linus Torvalds

signal: trivial, fix the "timespec declared inside parameter list" warning

2011-05-18T13:08:03+00:00

Fix the compile warning, do_sigtimedwait(struct timespec *) in signal.h
needs the forward declaration of timespec.

Reported-and-acked-by: Mike Frysinger 
Signed-off-by: Oleg Nesterov

signal: rename signandsets() to sigandnsets()

2011-04-28T11:01:39+00:00

As Tejun and Linus pointed out, "nand" is the wrong name for "x & ~y",
it should be "andn". Rename signandsets() as suggested.

Suggested-by: Tejun Heo 
Signed-off-by: Oleg Nesterov 
Acked-by: Tejun Heo

signal: introduce do_sigtimedwait() to factor out compat/native code

2011-04-28T11:01:38+00:00

Factor out the common code in sys_rt_sigtimedwait/compat_sys_rt_sigtimedwait
to the new helper, do_sigtimedwait().

Add the comment to document the extra tick we add to timespec_to_jiffies(ts),
thanks to Linus who explained this to me.

Perhaps it would be better to move compat_sys_rt_sigtimedwait() into
signal.c under CONFIG_COMPAT, then we can make do_sigtimedwait() static.

Signed-off-by: Oleg Nesterov 
Acked-by: Tejun Heo 
Reviewed-by: Matt Fleming

signal: sigprocmask() should do retarget_shared_pending()

2011-04-28T11:01:37+00:00

In short, almost every changing of current->blocked is wrong, or at least
can lead to the unexpected results.

For example. Two threads T1 and T2, T1 sleeps in sigtimedwait/pause/etc.
kill(tgid, SIG) can pick T2 for TIF_SIGPENDING. If T2 calls sigprocmask()
and blocks SIG before it notices the pending signal, nobody else can handle
this pending shared signal.

I am not sure this is bug, but at least this looks strange imho. T1 should
not sleep forever, there is a signal which should wake it up.

This patch moves the code which actually changes ->blocked into the new
helper, set_current_blocked() and changes this code to call
retarget_shared_pending() as exit_signals() does. We should only care about
the signals we just blocked, we use "newset & ~current->blocked" as a mask.

We do not check !sigisemptyset(newblocked), retarget_shared_pending() is
cheap unless mask & shared_pending.

Note: for this particular case we could simply change sigprocmask() to
return -EINTR if signal_pending(), but then we should change other callers
and, more importantly, if we need this fix then set_current_blocked() will
have more callers and some of them can't restart. See the next patch as a
random example.

Signed-off-by: Oleg Nesterov 
Reviewed-by: Matt Fleming 
Acked-by: Tejun Heo

sysctl extern cleanup: signal

2010-03-12T23:52:44+00:00

Extern declarations in sysctl.c should be moved to their own header file,
and then include them in relavant .c files.

Move print_fatal_signals extern declaration to linux/signal.h

Signed-off-by: Dave Young 
Cc: Oleg Nesterov 
Cc: Roland McGrath 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

signals: introduce do_send_sig_info() helper

2009-09-24T14:21:01+00:00

Introduce do_send_sig_info() and convert group_send_sig_info(),
send_sig_info(), do_send_specific() to use this helper.

Hopefully it will have more users soon, it allows to specify
specific/group behaviour via "bool group" argument.

Shaves 80 bytes from .text.

Signed-off-by: Oleg Nesterov 
Cc: Peter Zijlstra 
Cc: stephane eranian 
Cc: Ingo Molnar 
Cc: Roland McGrath 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

signals: implement sys_rt_tgsigqueueinfo

2009-04-30T17:24:24+00:00

sys_kill has the per thread counterpart sys_tgkill. sigqueueinfo is
missing a thread directed counterpart. Such an interface is important
for migrating applications from other OSes which have the per thread
delivery implemented.

Signed-off-by: Thomas Gleixner 
Reviewed-by: Oleg Nesterov 
Acked-by: Roland McGrath 
Acked-by: Ulrich Drepper