Commit Graph

92 Commits

Author SHA1 Message Date
Martin Schwidefsky
b5f87f15e2 s390/idle: consolidate idle functions and definitions
Move the C functions and definitions related to the idle state handling
to arch/s390/include/asm/idle.h and arch/s390/kernel/idle.c. The function
s390_get_idle_time is renamed to arch_cpu_idle_time and vtime_stop_cpu to
enabled_wait.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-09 09:14:03 +02:00
Martin Schwidefsky
d3a73acbc2 s390: split TIF bits into CIF, PIF and TIF bits
The oi and ni instructions used in entry[64].S to set and clear bits
in the thread-flags are not guaranteed to be atomic in regard to other
CPUs. Split the TIF bits into CPU, pt_regs and thread-info specific
bits. Updates on the TIF bits are done with atomic instructions,
updates on CPU and pt_regs bits are done with non-atomic instructions.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-05-20 08:58:47 +02:00
Martin Schwidefsky
9efe4f2992 s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
Skip the call to brk_rnd() if the PF_RANDOMIZE flag is not set for
the process. This avoids the costly get_random_int() call. Modify
arch_randomize_brk() as well to make it look like randomize_et_dyn().

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-18 17:36:38 +01:00
Martin Schwidefsky
4725c86055 s390: fix save and restore of the floating-point-control register
The FPC_VALID_MASK has been used to check the validity of the value
to be loaded into the floating-point-control register. With the
introduction of the floating-point extension facility and the
decimal-floating-point additional bits have been defined which need
to be checked in a non straight forward way. So far these bits have
been ignored which can cause an incorrect results for decimal-
floating-point operations, e.g. an incorrect rounding mode to be
set after signal return.

The static check with the FPC_VALID_MASK is replaced with a trial
load of the floating-point-control value, see test_fp_ctl.

In addition an information leak with the padding word between the
floating-point-control word and the floating-point registers in
the s390_fp_regs is fixed.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:11 +02:00
Martin Schwidefsky
e258d719ff s390/uaccess: always run the kernel in home space
Simplify the uaccess code by removing the user_mode=home option.
The kernel will now always run in the home space mode.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:57 +02:00
Martin Schwidefsky
0587d409ec s390/time: return with irqs disabled from psw_idle
Modify the psw_idle waiting logic in entry[64].S to return with
interrupts disabled. This avoids potential issues with udelay
and interrupt loops as interrupts are not reenabled after
clock comparator interrupts.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-28 09:19:23 +02:00
Thomas Gleixner
52c0065947 s390: Use generic idle loop
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Link: http://lkml.kernel.org/r/20130321215235.090816526@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-08 17:39:27 +02:00
Al Viro
afa86fc426 flagday: don't pass regs to copy_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 23:43:42 -05:00
Al Viro
87f1ca8fd9 s390: switch to generic fork/vfork/clone
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 22:44:37 -05:00
Linus Torvalds
42859eea96 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull generic execve() changes from Al Viro:
 "This introduces the generic kernel_thread() and kernel_execve()
  functions, and switches x86, arm, alpha, um and s390 over to them."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits)
  s390: convert to generic kernel_execve()
  s390: switch to generic kernel_thread()
  s390: fold kernel_thread_helper() into ret_from_fork()
  s390: fold execve_tail() into start_thread(), convert to generic sys_execve()
  um: switch to generic kernel_thread()
  x86, um/x86: switch to generic sys_execve and kernel_execve
  x86: split ret_from_fork
  alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
  alpha: switch to generic kernel_thread()
  alpha: switch to generic sys_execve()
  arm: get rid of execve wrapper, switch to generic execve() implementation
  arm: optimized current_pt_regs()
  arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
  arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk]
  generic sys_execve()
  generic kernel_execve()
  new helper: current_pt_regs()
  preparation for generic kernel_thread()
  um: kill thread->forking
  um: let signal_delivered() do SIGTRAP on singlestepping into handler
  ...
2012-10-10 12:02:25 +09:00
Al Viro
f9a7e025df s390: switch to generic kernel_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 23:03:03 -04:00
Al Viro
37fe5d41f6 s390: fold kernel_thread_helper() into ret_from_fork()
... and don't bother with syscall return path in case of kernel
threads.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 23:03:03 -04:00
Al Viro
65f22a906e s390: fold execve_tail() into start_thread(), convert to generic sys_execve()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 23:03:02 -04:00
Heiko Carstens
f6e38691a2 s390/process: add missing header include
Add appropriate header file:

arch/s390/kernel/process.c:327:15: warning: symbol 'arch_align_stack' was not declared.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26 15:45:22 +02:00
Jan Glauber
e4b8b3f33f s390: add support for runtime instrumentation
Allow user-space threads to use runtime instrumentation (RI). To enable RI
for a thread there is a new s390 specific system call, sys_s390_runtime_instr,
that takes as parameter a realtime signal number. If the RI facility is
available the system call sets up a control block for the calling thread with
the appropriate permissions for the thread to modify the control block.

The user-space thread can then use the store and modify RI instructions to
alter the control block and start/stop the instrumentation via RION/RIOFF.

If the user specified program buffer runs full RI triggers an external
interrupt. The external interrupt is translated to a real-time signal that
is delivered to the thread that enabled RI on that CPU. The number of
the real-time signal is the number specified in the RI system call. So,
user-space can select any available real-time signal number in case the
application itself uses real-time signals for other purposes.

The kernel saves the RI control blocks on task switch only if the running
thread was enabled for RI. Therefore, the performance impact on task switch
should be negligible if RI is not used.

RI is only enabled for user-space mode and is disabled for the supervisor
state.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26 15:45:02 +02:00
Martin Schwidefsky
27f6b41662 s390/vtimer: rework virtual timer interface
The current virtual timer interface is inherently per-cpu and hard to
use. The sole user of the interface is appldata which uses it to execute
a function after a specific amount of cputime has been used over all cpus.

Rework the virtual timer interface to hook into the cputime accounting.
This makes the interface independent from the CPU timer interrupts, and
makes the virtual timers global as opposed to per-cpu.
Overall the code is greatly simplified. The downside is that the accuracy
is not as good as the original implementation, but it is still good enough
for appldata.

Reviewed-by: Jan Glauber <jang@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-07-20 11:15:08 +02:00
Heiko Carstens
a53c8fab3f s390/comments: unify copyright messages and remove file names
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00
David Howells
a0616cdebc Disintegrate asm/system.h for S390
Disintegrate asm/system.h for S390.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-s390@vger.kernel.org
2012-03-28 18:30:02 +01:00
Linus Torvalds
db14179679 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 patches from Martin Schwidefsky:
 "The biggest patch is the rework of the smp code, something I wanted to
  do for some time.  There are some patches for our various dump methods
  and one new thing: z/VM LGR detection.  LGR stands for linux-guest-
  relocation and is the guest migration feature of z/VM.  For debugging
  purposes we keep a log of the systems where a specific guest has lived."

Fix up trivial conflict in arch/s390/kernel/smp.c due to the scheduler
cleanup having removed some code next to removed s390 code.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  [S390] kernel: Pass correct stack for smp_call_ipl_cpu()
  [S390] Ensure that vmcore_info pointer is never accessed directly
  [S390] dasd: prevent validate server for offline devices
  [S390] Remove monolithic build option for zcrypt driver.
  [S390] stack dump: fix indentation in output
  [S390] kernel: Add OS info memory interface
  [S390] Use block_sigmask()
  [S390] kernel: Add z/VM LGR detection
  [S390] irq: external interrupt code passing
  [S390] irq: set __ARCH_IRQ_EXIT_IRQS_DISABLED
  [S390] zfcpdump: Implement async sdias event processing
  [S390] Use copy_to_absolute_zero() instead of "stura/sturg"
  [S390] rework idle code
  [S390] rework smp code
  [S390] rename lowcore field
  [S390] Fix gcc 4.6.0 compile warning
2012-03-22 18:15:32 -07:00
Martin Schwidefsky
4c1051e37a [S390] rework idle code
Whenever the cpu loads an enabled wait PSW it will appear as idle to the
underlying host system. The code in default_idle calls vtime_stop_cpu
which does the necessary voodoo to get the cpu time accounting right.
The udelay code just loads an enabled wait PSW. To correct this rework
the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts
to entry[64].S, vtime_stop_cpu can now be called from anywhere and
vtime_start_cpu is gone. The correction of the cpu time during wakeup
from an enabled wait PSW is done with a critical section in entry[64].S.
As vtime_start_cpu is gone, s390_idle_check can be removed as well.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11 11:59:28 -04:00
Thomas Gleixner
bd2f55361f sched/rt: Use schedule_preempt_disabled()
Coccinelle based conversion.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01 10:28:03 +01:00
Heiko Carstens
048cd4e51d compat: fix compile breakage on s390
The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.

This is the minimal patch which fixes the build issues.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-27 07:54:27 -08:00
Heiko Carstens
f3612304ee [S390] idle: avoid RCU usage in extended quiescent state
Avoid calling wake_up() from our NMI "bottom halve" from RCU extended
quiescent state in idle. wake_up() has RCU read-side critical sections
but this will be completely ignored by RCU if the cpu is in extended
quiescent state.
Which means that whatever object is being accessed from within the
read-side critical section can be freed concurrently from a different
cpu.
So make sure we leave extended quiescent state before calling wake_up().

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-02-17 10:29:32 +01:00
Frederic Weisbecker
1268fbc746 nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu()
Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.

Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:57 -08:00
Frederic Weisbecker
2bbb6817c0 nohz: Allow rcu extended quiescent state handling seperately from tick stop
It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.

To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().

If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().

Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:

- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:36 -08:00
Frederic Weisbecker
280f06774a nohz: Separate out irq exit and idle loop dyntick logic
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:

- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.

There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.

Split this function into:

- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.

- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).

To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().

This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:35 -08:00
Martin Schwidefsky
638ad34a88 [S390] sparse: fix sparse warnings about missing prototypes
Add prototypes and includes for functions used in different modules.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:46 +01:00
Martin Schwidefsky
b50511e41a [S390] cleanup psw related bits and pieces
Split out addressing mode bits from PSW_BASE_BITS, rename PSW_BASE_BITS
to PSW_MASK_BASE, get rid of psw_user32_bits, remove unused function
enabled_wait(), introduce PSW_MASK_USER, and drop PSW_MASK_MERGE macros.
Change psw_kernel_bits / psw_user_bits to contain only the bits that
are always set in the respective mode.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:43 +01:00
Jan Glauber
3af6fb687b [S390] Remove unused includes in process.c
Remove unsused includes from arch/s390/kernel/process.c.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-05-23 10:24:32 +02:00
Heiko Carstens
d2c9dfccbc [S390] Randomize PIEs
Randomize ELF_ET_DYN_BASE, which is used when loading position
independent executables.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-12 09:55:25 +01:00
Heiko Carstens
3351918282 [S390] Randomise the brk region
Randomize heap address like other architectures do already.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-12 09:55:25 +01:00
Heiko Carstens
9887a1fcdd [S390] Randomize lower bits of stack address
Randomize the lower bits of the stack address like x86 and powerpc.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-12 09:55:25 +01:00
Martin Schwidefsky
5e9a26928f [S390] ptrace cleanup
Overhaul program event recording and the code dealing with the ptrace
user space interface.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:31 +01:00
Heiko Carstens
da7f51c11d [S390] smp/idle: call init_idle() before starting a new cpu
Call init_idle() which (re-)initializes the idle task structure before
it gets used on a new cpu.
That way we can also get rid of the odd preempt_enable_no_resched()
call we have in the cpu offline path within cpu_idle(). That call
prevented preempt count imbalances between cpu hotplug operations.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:30 +01:00
Martin Schwidefsky
860dba45e8 [S390] add kprobes annotations
Add kprobes annotations to get the massive 'probe kernel.function("*") {}'
stress test working.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:24 +01:00
Heiko Carstens
6931be0803 [S390] cpu hotplug/idle: move cpu_die call to enabled context
There is no difference if cpu_die is called from enabled or disabled
context. Except that the fast_gup code might be called via
cpu_die -> idle_task_exit -> __mm_drop -> crst_table_free. Which in
turn grabs and releases a spinlock using the _bh ops, which is not
allowed in irq disabled context, since spin_unlock_bh will
unconditionally enable interrupts again.
To get rid of the warning emitted by the softirq code just move the
code to enabled context.

In this case this doesn't fix a bug, we just get rid of a warning.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25 16:10:15 +02:00
David Howells
d7627467b7 Make do_execve() take a const filename pointer
Make do_execve() take a const filename pointer so that kernel_execve() compiles
correctly on ARM:

arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type

This also requires the argv and envp arguments to be consted twice, once for
the pointer array and once for the strings the array points to.  This is
because do_execve() passes a pointer to the filename (now const) to
copy_strings_kernel().  A simpler alternative would be to cast the filename
pointer in do_execve() when it's passed to copy_strings_kernel().

do_execve() may not change any of the strings it is passed as part of the argv
or envp lists as they are some of them in .rodata, so marking these strings as
const should be fine.

Further kernel_execve() and sys_execve() need to be changed to match.

This has been test built on x86_64, frv, arm and mips.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-17 18:07:43 -07:00
David Howells
c788732523 Mark arguments to certain syscalls as being const
Mark arguments to certain system calls as being const where they should be but
aren't.  The list includes:

 (*) The filename arguments of various stat syscalls, execve(), various utimes
     syscalls and some mount syscalls.

 (*) The filename arguments of some syscall helpers relating to the above.

 (*) The buffer argument of various write syscalls.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-13 16:53:13 -07:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Martin Schwidefsky
bebf023d41 [S390] remove superfluous TIF_USEDFPU bit
The TIF_USEDFPU bit is always 0 for s390 and it is not tested anywhere.
Remove the bit. At the same time remove the calls to clear_used_math()
as well. The PF_USED_MATH bit is never set for s390 either.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-01-13 20:44:44 +01:00
Martin Schwidefsky
f8d5faf718 [S390] clear TIF_SINGLE_STEP for new process.
Clear the TIF_SINGLE_STEP bit in copy_thread. The new process did not get
a PER event of its own. It is wrong deliver a SIGTRAP that was meant for
the parent process.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-01-13 20:44:44 +01:00
Alexey Dobriyan
2bcd57ab61 headers: utsname.h redux
* remove asm/atomic.h inclusion from linux/utsname.h --
   not needed after kref conversion
 * remove linux/utsname.h inclusion from files which do not need it

NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
due to some personality stuff it _is_ needed -- cowardly leave ELF-related
headers and files alone.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 18:13:10 -07:00
Heiko Carstens
3e86a8c617 [S390] Convert sys_execve to function with parameters.
Use function parameters instead of accessing the pt_regs structure
to get the parameters.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-22 22:58:43 +02:00
Heiko Carstens
2d70ca23f8 [S390] Convert sys_clone to function with parameters.
Use function parameters instead of accessing the pt_regs structure
to get the parameters.
Also merge the 31 and 64 bit versions since they are identical.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-22 22:58:43 +02:00
Oleg Nesterov
bba7fc0a21 ptrace: remove PT_DTRACE from avr32, mn10300, parisc, s390, sh, xtensa
avr32, mn10300, parisc, s390, sh, xtensa:

They never set PT_DTRACE, but clear it after do_execve().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Chris Zankel <chris@zankel.net>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:48 -07:00
Heiko Carstens
7757591ab4 [S390] implement is_compat_task
Implement is_compat_task and use it all over the place.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12 10:27:30 +02:00
Alexey Dobriyan
6f2c55b843 Simplify copy_thread()
First argument unused since 2.3.11.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:51 -07:00
Heiko Carstens
1485c5c884 [S390] move EXPORT_SYMBOLs to definitions
Move all EXPORT_SYMBOLs to their corresponding definitions.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:11 +01:00
Heiko Carstens
f5daba1d41 [S390] split/move machine check handler code
Split machine check handler code and move it to cio and kernel code
where it belongs to. No functional change.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:10 +01:00
Heiko Carstens
5168ce2c64 [S390] cputime: initialize per thread timer values on fork
Initialize per thread timer values instead of just copying them from
the parent. That way it is easily possible to tell how much time a
thread spent in user/system context.
Doesn't fix a bug, this is just for debugging purposes.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:07 +01:00