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643 Commits (7e47682ea555e7c1edef1d8fd96e2aa4c12abe59)

Author SHA1 Message Date
Viresh Kumar 0a0fca9d83 sched: Rename sched.c as sched/core.c in comments and Documentation
Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time
back and the comments/Documentation never got updated.

I figured it out when I was going through sched-domains.txt and so thought of
fixing it globally.

I haven't crossed check if the stuff that is referenced in sched/core.c by all
these files is still present and hasn't changed as that wasn't the motive behind
this patch.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19 12:58:42 +02:00
Tejun Heo 196779b9b4 dump_stack: consolidate dump_stack() implementations and unify their behaviors
Both dump_stack() and show_stack() are currently implemented by each
architecture.  show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack().  On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.

The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().

There's no reason to require archs to implement two separate but mostly
identical functions.  It leads to unnecessary subtle information.

This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin.  Blackfin's
dump_stack() does something wonky that I don't understand.

Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information.  This is used
in blackfin.

This patch brings the following behavior changes.

* On some archs, an extra level in backtrace for show_stack() could be
  printed.  This is because the top frame was determined in
  dump_stack() on those archs while generic dump_stack() can't do that
  reliably.  It can be compensated by inlining dump_stack() but not
  sure whether that'd be necessary.

* Most archs didn't use to print debug info on dump_stack().  They do
  now.

An example WARN dump follows.

 WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
 Hardware name: empty
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
  0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
  ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
  0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
 Call Trace:
  [<ffffffff81c614dc>] dump_stack+0x19/0x1b
  [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
  [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff8234a071>] init_workqueues+0x35/0x505
  ...

v2: CPU number added to the generic debug info as requested by s390
    folks and dropped the s390 specific dump_stack().  This loses %ksp
    from the debug message which the maintainers think isn't important
    enough to keep the s390-specific dump_stack() implementation.

    dump_stack_print_info() is moved to kernel/printk.c from
    lib/dump_stack.c.  Because linkage is per objecct file,
    dump_stack_print_info() living in the same lib file as generic
    dump_stack() means that archs which implement custom dump_stack()
    - at this point, only blackfin - can't use dump_stack_print_info()
    as that will bring in the generic version of dump_stack() too.  v1
    The v1 patch broke build on blackfin due to this issue.  The build
    breakage was reported by Fengguang Wu.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>	[s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:02 -07:00
Linus Torvalds 8700c95adb Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP/hotplug changes from Ingo Molnar:
 "This is a pretty large, multi-arch series unifying and generalizing
  the various disjunct pieces of idle routines that architectures have
  historically copied from each other and have grown in random, wildly
  inconsistent and sometimes buggy directions:

   101 files changed, 455 insertions(+), 1328 deletions(-)

  this went through a number of review and test iterations before it was
  committed, it was tested on various architectures, was exposed to
  linux-next for quite some time - nevertheless it might cause problems
  on architectures that don't read the mailing lists and don't regularly
  test linux-next.

  This cat herding excercise was motivated by the -rt kernel, and was
  brought to you by Thomas "the Whip" Gleixner."

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  idle: Remove GENERIC_IDLE_LOOP config switch
  um: Use generic idle loop
  ia64: Make sure interrupts enabled when we "safe_halt()"
  sparc: Use generic idle loop
  idle: Remove unused ARCH_HAS_DEFAULT_IDLE
  bfin: Fix typo in arch_cpu_idle()
  xtensa: Use generic idle loop
  x86: Use generic idle loop
  unicore: Use generic idle loop
  tile: Use generic idle loop
  tile: Enter idle with preemption disabled
  sh: Use generic idle loop
  score: Use generic idle loop
  s390: Use generic idle loop
  powerpc: Use generic idle loop
  parisc: Use generic idle loop
  openrisc: Use generic idle loop
  mn10300: Use generic idle loop
  mips: Use generic idle loop
  microblaze: Use generic idle loop
  ...
2013-04-30 07:50:17 -07:00
Thomas Gleixner d0380e6c3c early_printk: consolidate random copies of identical code
The early console implementations are the same all over the place.  Move
the print function to kernel/printk and get rid of the copies.

[akpm@linux-foundation.org: arch/mips/kernel/early_printk.c needs kernel.h for va_list]
[paul.gortmaker@windriver.com: sh4: make the bios early console support depend on EARLY_PRINTK]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:13 -07:00
Jiang Liu 5b472b2057 mm/um: use free_highmem_page() to free highmem pages into buddy system
Use helper function free_highmem_page() to free highmem pages into
the buddy system.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:32 -07:00
Jiang Liu e16e0b1b98 mm/um: use common help functions to free reserved pages
Use common help functions to free reserved pages.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:31 -07:00
Richard Weinberger 8198c1696a um: Use generic idle loop
Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: user-mode-linux-devel@lists.sourceforge.net
Link: http://lkml.kernel.org/r/1366149209-24787-1-git-send-email-richard@nod.at
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 10:39:38 +02:00
Al Viro 15ce1f7154 x86,um: switch to generic old sigsuspend()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:16:26 -05:00
Al Viro 6bf9adfc90 introduce generic sys_sigaltstack(), switch x86 and um to it
Conditional on CONFIG_GENERIC_SIGALTSTACK; architectures that do not
select it are completely unaffected

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-19 18:07:40 -05:00
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 1d4b4b2994 x86, um: switch to generic fork/vfork/clone
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 22:13:44 -05:00
Al Viro 2b067fc9dd um: don't bother looking at regs in copy_thread() - current_pt_regs() is what we'll get
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:49:03 -05:00
Al Viro 8cddebd767 um: don't bother with passing sp to do_fork() for fork(2)/vfork(2)
copy_thread() on um will do the right thing when getting 0 for sp...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:49:03 -05:00
Al Viro 9436d5c32b um: get_safe_registers() should be done in flush_thread(), not start_thread()
... or we'll end up buggering the results of ELF_PLAT_INIT()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:46:03 -05:00
Linus Torvalds 4e21fc138b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull third pile of kernel_execve() patches from Al Viro:
 "The last bits of infrastructure for kernel_thread() et.al., with
  alpha/arm/x86 use of those.  Plus sanitizing the asm glue and
  do_notify_resume() on alpha, fixing the "disabled irq while running
  task_work stuff" breakage there.

  At that point the rest of kernel_thread/kernel_execve/sys_execve work
  can be done independently for different architectures.  The only
  pending bits that do depend on having all architectures converted are
  restrictred to fs/* and kernel/* - that'll obviously have to wait for
  the next cycle.

  I thought we'd have to wait for all of them done before we start
  eliminating the longjump-style insanity in kernel_execve(), but it
  turned out there's a very simple way to do that without flagday-style
  changes."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  alpha: switch to saner kernel_execve() semantics
  arm: switch to saner kernel_execve() semantics
  x86, um: convert to saner kernel_execve() semantics
  infrastructure for saner ret_from_kernel_thread semantics
  make sure that kernel_thread() callbacks call do_exit() themselves
  make sure that we always have a return path from kernel_execve()
  ppc: eeh_event should just use kthread_run()
  don't bother with kernel_thread/kernel_execve for launching linuxrc
  alpha: get rid of switch_stack argument of do_work_pending()
  alpha: don't bother passing switch_stack separately from regs
  alpha: take SIGPENDING/NOTIFY_RESUME loop into signal.c
  alpha: simplify TIF_NEED_RESCHED handling
2012-10-13 10:05:52 +09:00
Al Viro 22e2430d60 x86, um: convert to saner kernel_execve() semantics
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 13:35:22 -04:00
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
Linus Torvalds f59b51fe3d Merge branch 'for-linus-37rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML changes from Richard Weinberger:
 "UML receives this time only cleanups.

  The most outstanding change is the 'include "foo.h"' do 'include
  <foo.h>' conversion done by Al Viro.

  It touches many files, that's why the diffstat is rather big."

* 'for-linus-37rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  typo in UserModeLinux-HOWTO
  hppfs: fix the return value of get_inode()
  hostfs: drop vmtruncate
  um: get rid of pointless include "..." where include <...> will do
  um: move sysrq.h out of include/shared
  um/x86: merge 32 and 64 bit variants of ptrace.h
  um/x86: merge 32 and 64bit variants of checksum.h
2012-10-10 11:15:20 +09:00
Al Viro 37185b3324 um: get rid of pointless include "..." where include <...> will do
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-10-09 22:28:45 +02:00
Al Viro 382d95fdfa um: move sysrq.h out of include/shared
never used by userland-side objects

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-10-09 22:28:19 +02:00
Shaohua Li 45cac65b0f readahead: fault retry breaks mmap file read random detection
.fault now can retry.  The retry can break state machine of .fault.  In
filemap_fault, if page is miss, ra->mmap_miss is increased.  In the second
try, since the page is in page cache now, ra->mmap_miss is decreased.  And
these are done in one fault, so we can't detect random mmap file access.

Add a new flag to indicate .fault is tried once.  In the second try, skip
ra->mmap_miss decreasing.  The filemap_fault state machine is ok with it.

I only tested x86, didn't test other archs, but looks the change for other
archs is obvious, but who knows :)

Signed-off-by: Shaohua Li <shaohua.li@fusionio.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:47 +09:00
Al Viro 1f02ab4a23 um: switch to generic kernel_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 22:53:32 -04:00
Al Viro 6783eaa2e1 x86, um/x86: switch to generic sys_execve and kernel_execve
32bit wrapper is lost on that; 64bit one is *not*, since
we need to arrange for full pt_regs on stack when we call
sys_execve() and we need to load callee-saved ones from
there afterwards.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 22:53:32 -04:00
Al Viro d2ce4e92fa um: kill thread->forking
we only use that to tell copy_thread() done by syscall from that
done by kernel_thread().  However, it's easier to do simply by
checking PF_KTHREAD in thread flags.

Merge sys_clone() guts for 32bit and 64bit, while we are at it...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-27 18:04:55 +02:00
Al Viro f9a38eace4 um: let signal_delivered() do SIGTRAP on singlestepping into handler
... rather than duplicating that in sigframe setup code (and doing that
inconsistently, at that)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-27 18:04:47 +02:00
Al Viro bf56d57638 um: don't leak floating point state and segment registers on execve()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-27 18:04:38 +02:00
Al Viro 424597921a um: take cleaning singlestep to start_thread()
... assuming it's needed to be done at all

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-27 18:04:26 +02:00
Al Viro a4d94ff8aa um: kill thread->forking
we only use that to tell copy_thread() done by syscall from that
done by kernel_thread().  However, it's easier to do simply by
checking PF_KTHREAD in thread flags.

Merge sys_clone() guts for 32bit and 64bit, while we are at it...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-20 10:49:09 -04:00
Al Viro 8e2c85aa6c um: let signal_delivered() do SIGTRAP on singlestepping into handler
... rather than duplicating that in sigframe setup code (and doing that
inconsistently, at that)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-20 09:53:01 -04:00
Al Viro 344569aef3 um: don't leak floating point state and segment registers on execve()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-20 09:53:01 -04:00
Al Viro ab286b21aa um: take cleaning singlestep to start_thread()
... assuming it's needed to be done at all

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-20 09:53:00 -04:00
Linus Torvalds 1871e845e5 Merge branch 'for-linus-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML fixes from Richard Weinberger:
 "This patch set contains mostly fixes and cleanups.  The UML tty driver
  uses now tty_port and is no longer broken like hell  :-)"

* 'for-linus-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Add arch/x86/um to MAINTAINERS
  um: pass siginfo to guest process
  um: fix ubd_file_size for read-only files
  um: pull interrupt_end() into userspace()
  um: split syscall_trace(), pass pt_regs to it
  um: switch UPT_SET_RETURN_VALUE and regs_return_value to pt_regs
  um: set BLK_CGROUP=y in defconfig
  um: remove count_lock
  um: fully use tty_port
  um: Remove dead code
  um: remove line_ioctl()
  TTY: um/line, use tty from tty_port
  TTY: um/line, add tty_port
2012-08-01 16:45:02 -07:00
Martin Pärtel d3c1cfcdb4 um: pass siginfo to guest process
UML guest processes now get correct siginfo_t for SIGTRAP, SIGFPE,
SIGILL and SIGBUS. Specifically, si_addr and si_code are now correct
where previously they were si_addr = NULL and si_code = 128.

Signed-off-by: Martin Pärtel <martin.partel@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-08-02 00:49:17 +02:00
Al Viro b8a4209523 um: pull interrupt_end() into userspace()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-08-02 00:25:44 +02:00
Al Viro 1bfa2317b2 um: split syscall_trace(), pass pt_regs to it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[richard@nod.at: Fixed some minor build issues]
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-08-02 00:25:38 +02:00
Al Viro a3170d2ec2 um: switch UPT_SET_RETURN_VALUE and regs_return_value to pt_regs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-08-01 23:33:16 +02:00
Theodore Ts'o aab944606f um: remove IRQF_SAMPLE_RANDOM which is now a no-op
With the changes in the random tree, IRQF_SAMPLE_RANDOM is now a
no-op; interrupt randomness is now collected unconditionally in a very
low-overhead fashion; see commit 775f4b297b.  The IRQF_SAMPLE_RANDOM
flag was scheduled to be removed in 2009 on the
feature-removal-schedule, so this patch is preparation for the final
removal of this flag.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
2012-07-19 10:40:42 -04:00
Al Viro efee984c27 new helper: signal_delivered()
Does block_sigmask() + tracehook_signal_handler();  called when
sigframe has been successfully built.  All architectures converted
to it; block_sigmask() itself is gone now (merged into this one).

I'm still not too happy with the signature, but that's a separate
story (IMO we need a structure that would contain signal number +
siginfo + k_sigaction, so that get_signal_to_deliver() would fill one,
signal_delivered(), handle_signal() and probably setup...frame() -
take one).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:52 -04:00
Al Viro 77097ae503 most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set
Only 3 out of 63 do not.  Renamed the current variant to __set_current_blocked(),
added set_current_blocked() that will exclude unblockable signals, switched
open-coded instances to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:51 -04:00
Al Viro a610d6e672 pull clearing RESTORE_SIGMASK into block_sigmask()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:49 -04:00
Al Viro b7f9a11a6c new helper: sigmask_to_save()
replace boilerplate "should we use ->saved_sigmask or ->blocked?"
with calls of obvious inlined helper...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:48 -04:00
Al Viro 51a7b448d4 new helper: restore_saved_sigmask()
first fruits of ..._restore_sigmask() helpers: now we can take
boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK
and restore the blocked mask from ->saved_mask" into a common
helper.  Open-coded instances switched...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:47 -04:00
Linus Torvalds fb21affa49 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull second pile of signal handling patches from Al Viro:
 "This one is just task_work_add() series + remaining prereqs for it.

  There probably will be another pull request from that tree this
  cycle - at least for helpers, to get them out of the way for per-arch
  fixes remaining in the tree."

Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile
had brought in commit 97fd75b7b8 ("kernel/irq/manage.c: use the
pr_foo() infrastructure to prefix printks") which changed one of the
pr_err() calls that this merge moves around.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  keys: kill task_struct->replacement_session_keyring
  keys: kill the dummy key_replace_session_keyring()
  keys: change keyctl_session_to_parent() to use task_work_add()
  genirq: reimplement exit_irq_thread() hook via task_work_add()
  task_work_add: generic process-context callbacks
  avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers
  parisc: need to check NOTIFY_RESUME when exiting from syscall
  move key_repace_session_keyring() into tracehook_notify_resume()
  TIF_NOTIFY_RESUME is defined on all targets now
2012-05-31 18:47:30 -07:00
Anton Vorontsov 2c922c51e6 um: properly check all process' threads for a live mm
kill_off_processes() might miss a valid process, this is because checking
for process->mm is not enough.  Process' main thread may exit or detach
its mm via use_mm(), but other threads may still have a valid mm.

To catch this we use find_lock_task_mm(), which walks up all threads and
returns an appropriate task (with task lock held).

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:30 -07:00
Anton Vorontsov 137d1a26c8 um: fix possible race on task->mm
Checking for task->mm is dangerous as ->mm might disappear (exit_mm()
assigns NULL under task_lock(), so tasklist lock is not enough).

We can't use get_task_mm()/mmput() pair as mmput() might sleep, so let's
take the task lock while we care about its mm.

Note that we should also use find_lock_task_mm() to check all process'
threads for a valid mm, but for uml we'll do it in a separate patch.

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:30 -07:00
Anton Vorontsov 9bd0a07712 um: should hold tasklist_lock while traversing processes
Traversing the tasks requires holding tasklist_lock, otherwise it is
unsafe.

p.s.  However, I'm not sure that calling os_kill_ptraced_process() in the
atomic context is correct.  It seem to work, but please take a closer
look.

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:30 -07:00
Kautuk Consul 1cefe28f95 um/kernel/trap.c: port OOM changes to handle_page_fault()
Commit d065bd810b ("mm: retry page fault when blocking on disk
transfer") and commit 37b23e0525 ("x86,mm: make pagefault killable")
introduced changes into the x86 pagefault handler for making the page
fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial during OOM
killer invocation.

Port these changes to um.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:26 -07:00
Al Viro a42c6ded82 move key_repace_session_keyring() into tracehook_notify_resume()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-23 22:09:20 -04:00
Linus Torvalds f9369910a6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull first series of signal handling cleanups from Al Viro:
 "This is just the first part of the queue (about a half of it);
  assorted fixes all over the place in signal handling.

  This one ends with all sigsuspend() implementations switched to
  generic one (->saved_sigmask-based).

  With this, a bunch of assorted old buglets are fixed and most of the
  missing bits of NOTIFY_RESUME hookup are in place.  Two more fixes sit
  in arm and um trees respectively, and there's a couple of broken ones
  that need obvious fixes - parisc and avr32 check TIF_NOTIFY_RESUME
  only on one of two codepaths; fixes for that will happen in the next
  series"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (55 commits)
  unicore32: if there's no handler we need to restore sigmask, syscall or no syscall
  xtensa: add handling of TIF_NOTIFY_RESUME
  microblaze: drop 'oldset' argument of do_notify_resume()
  microblaze: handle TIF_NOTIFY_RESUME
  score: add handling of NOTIFY_RESUME to do_notify_resume()
  m68k: add TIF_NOTIFY_RESUME and handle it.
  sparc: kill ancient comment in sparc_sigaction()
  h8300: missing checks of __get_user()/__put_user() return values
  frv: missing checks of __get_user()/__put_user() return values
  cris: missing checks of __get_user()/__put_user() return values
  powerpc: missing checks of __get_user()/__put_user() return values
  sh: missing checks of __get_user()/__put_user() return values
  sparc: missing checks of __get_user()/__put_user() return values
  avr32: struct old_sigaction is never used
  m32r: struct old_sigaction is never used
  xtensa: xtensa_sigaction doesn't exist
  alpha: tidy signal delivery up
  score: don't open-code force_sigsegv()
  cris: don't open-code force_sigsegv()
  blackfin: don't open-code force_sigsegv()
  ...
2012-05-23 18:11:45 -07:00
Linus Torvalds 3a8580f820 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
 "Most changes are bug fixes and cleanups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: missing checks of __put_user()/__get_user() return values
  um: stub_rt_sigsuspend isn't needed these days anymore
  um/x86: merge (and trim) 32- and 64-bit variants of ptrace.h
  irq: Remove irq_chip->release()
  um: Remove CONFIG_IRQ_RELEASE_METHOD
  um: Remove usage of irq_chip->release()
  um: Implement um_free_irq()
  um: Fix __swp_type()
  um: Implement a custom pte_same() function
  um: Add BUG() to do_ops()'s error path
  um: Remove unused variables
  um: bury unused _TIF_RESTORE_SIGMASK
  um: wrong sigmask saved in case of multiple sigframes
  um: add TIF_NOTIFY_RESUME
  um: ->restart_block.fn needs to be reset on sigreturn
2012-05-23 09:01:41 -07:00
Al Viro 68f3f16d9a new helper: sigsuspend()
guts of saved_sigmask-based sigsuspend/rt_sigsuspend.  Takes
kernel sigset_t *.

Open-coded instances replaced with calling it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:52:30 -04:00
Richard Weinberger 2ccf62b360 Merge branch 'for-um' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal into for-3.5 2012-05-21 23:25:37 +02:00
Al Viro 243412be9c um/x86: merge (and trim) 32- and 64-bit variants of ptrace.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 16:28:34 -04:00
Richard Weinberger 8e514b2a81 um: Remove usage of irq_chip->release()
UML does no longer need irq_chip->release().

Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-21 21:09:36 +02:00
Richard Weinberger fa7a0449e0 um: Implement um_free_irq()
Instead of using chip->release() we can achieve the same
using a simple wrapper for free_irq().
We have already um_request_irq(), so um_free_irq() is the perfect
counterpart.

Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-21 21:09:36 +02:00
Richard Weinberger 62179d47c2 um: Add BUG() to do_ops()'s error path
In case we encounter a bad operation in do_ops() something is really
broken and it's better to BUG().

Signed-off-by: Richard Weinberger <richard@nod.at>
2012-05-21 21:09:33 +02:00
Al Viro 5a30a798fb um: wrong sigmask saved in case of multiple sigframes
we can't just find oldmask once; if there are multiple signals
and we loop building sigframes for those, ->saved_mask will be
definitely wrong for all but the first one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 14:20:27 -04:00
Al Viro d50349b0c3 um: add TIF_NOTIFY_RESUME
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 14:19:53 -04:00
Al Viro 3b7d15bde5 um: ->restart_block.fn needs to be reset on sigreturn
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 14:19:31 -04:00
Thomas Gleixner 5b408241e9 um: Use generic init_task
Same code. Use the generic version.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/20120503085035.592937512@linutronix.de
2012-05-05 13:00:26 +02:00
Thomas Gleixner 8239c25f47 smp: Add task_struct argument to __cpu_up()
Preparatory patch to make the idle thread allocation for secondary
cpus generic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
2012-04-26 12:06:09 +02:00
Boaz Harrosh 657b12d3a1 um: uml_setup_stubs': warning: unused variable 'pages'
Fix the following gcc complain
arch/um/kernel/skas/mmu.c: In function 'uml_setup_stubs':
arch/um/kernel/skas/mmu.c:106:16: warning: unused variable 'pages' [-Wunused-variable]

Signed-Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-04-10 00:13:45 +02:00
Richard Weinberger 76b278edd9 um: Use asm-generic/switch_to.h
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-04-10 00:13:45 +02:00
Al Viro 3cb42092ff um: fix linker script generation
while we can't just use -U$(SUBARCH), we still need to kill idiotic define
(implicit -Di386=1), both for SUBARCH=i386 and SUBARCH=x86/CONFIG_64BIT=n
builds.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-04-09 13:59:00 -04:00
Rusty Russell 0b5f9c005d remove references to cpu_*_map in arch/
This has been obsolescent for a while; time for the final push.

In adjacent context, replaced old cpus_* with cpumask_*.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net> (arch/sparc)
Acked-by: Chris Metcalf <cmetcalf@tilera.com> (arch/tile)
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: sparclinux@vger.kernel.org
2012-03-29 15:38:30 +10:30
Linus Torvalds fa453a625d Merge branch 'for-linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML changes from Richard Weinberger:
 "Mostly bug fixes and cleanups"

* 'for-linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (35 commits)
  um: Update defconfig
  um: Switch to large mcmodel on x86_64
  MTD: Relax dependencies
  um: Wire CONFIG_GENERIC_IO up
  um: Serve io_remap_pfn_range()
  Introduce CONFIG_GENERIC_IO
  um: allow SUBARCH=x86
  um: most of the SUBARCH uses can be killed
  um: deadlock in line_write_interrupt()
  um: don't bother trying to rebuild CHECKFLAGS for USER_OBJS
  um: use the right ifdef around exports in user_syms.c
  um: a bunch of headers can be killed by using generic-y
  um: ptrace-generic.h doesn't need user.h
  um: kill HOST_TASK_PID
  um: remove pointless include of asm/fixmap.h from asm/pgtable.h
  um: asm-offsets.h might as well come from underlying arch...
  um: merge processor_{32,64}.h a bit...
  um: switch close_chan() to struct line
  um: race fix: initialize delayed_work *before* registering IRQ
  um: line->have_irq is never checked...
  ...
2012-03-27 18:29:53 -07:00
Al Viro dc5be20a64 um: most of the SUBARCH uses can be killed
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[richard@nod.at: Re-export SUBARCH in arch/um/Makefile]
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25 00:29:56 +01:00
Al Viro c2220b2a12 um: kill HOST_TASK_PID
just provide get_current_pid() to the userland side of things
instead of get_current() + manual poking in its results

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25 00:29:55 +01:00
Yong Zhang c0b79a90b1 um: irq: Remove IRQF_DISABLED
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25 00:29:52 +01:00
Matt Fleming d982d5955e um: use set_current_blocked() and block_sigmask()
As described in commit e6fa16ab9c ("signal: sigprocmask() should do
retarget_shared_pending()") the modification of current->blocked is
incorrect as we need to check whether the signal we're about to block is
pending in the shared queue.

Also, use the new helper function introduced in commit 5e6292c0f2
("signal: add block_sigmask() for adding sigmask to current->blocked")
which centralises the code for updating current->blocked after
successfully delivering a signal and reduces the amount of duplicate
code across architectures.  In the past some architectures got this code
wrong, so using this helper function should stop that from happening
again.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:31 -07:00
Matt Fleming f6adb9a6ae um: don't restore current->blocked on error
If we fail to setup the signal stack frame then we don't need to restore
current->blocked because it is not modified by setup_signal_stack_*.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:31 -07:00
Linus Torvalds e2a0883e40 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 1 from Al Viro:
 "This is _not_ all; in particular, Miklos' and Jan's stuff is not there
  yet."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
  ext4: initialization of ext4_li_mtx needs to be done earlier
  debugfs-related mode_t whack-a-mole
  hfsplus: add an ioctl to bless files
  hfsplus: change finder_info to u32
  hfsplus: initialise userflags
  qnx4: new helper - try_extent()
  qnx4: get rid of qnx4_bread/qnx4_getblk
  take removal of PF_FORKNOEXEC to flush_old_exec()
  trim includes in inode.c
  um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
  um: embed ->stub_pages[] into mmu_context
  gadgetfs: list_for_each_safe() misuse
  ocfs2: fix leaks on failure exits in module_init
  ecryptfs: make register_filesystem() the last potential failure exit
  ntfs: forgets to unregister sysctls on register_filesystem() failure
  logfs: missing cleanup on register_filesystem() failure
  jfs: mising cleanup on register_filesystem() failure
  make configfs_pin_fs() return root dentry on success
  configfs: configfs_create_dir() has parent dentry in dentry->d_parent
  configfs: sanitize configfs_create()
  ...
2012-03-21 13:36:41 -07:00
Al Viro ac2aca2817 um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
... while calling uml_dup_mmap()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20 21:29:50 -04:00
Al Viro ea6fb41752 um: embed ->stub_pages[] into mmu_context
seriously, kmalloc() for two-element array of pointers?

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20 21:29:50 -04:00
Cong Wang 91f2359396 um: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:15 +08:00
Eric Paris b05d8447e7 audit: inline audit_syscall_entry to reduce burden on archs
Every arch calls:

if (unlikely(current->audit_context))
	audit_syscall_entry()

which requires knowledge about audit (the existance of audit_context) in
the arch code.  Just do it all in static inline in audit.h so that arch's
can remain blissfully ignorant.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:56 -05:00
Eric Paris d7e7528bcd Audit: push audit success and retcode into arch ptrace.h
The audit system previously expected arches calling to audit_syscall_exit to
supply as arguments if the syscall was a success and what the return code was.
Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things
by converting from negative retcodes to an audit internal magic value stating
success or failure.  This helper was wrong and could indicate that a valid
pointer returned to userspace was a failed syscall.  The fix is to fix the
layering foolishness.  We now pass audit_syscall_exit a struct pt_reg and it
in turns calls back into arch code to collect the return value and to
determine if the syscall was a success or failure.  We also define a generic
is_syscall_success() macro which determines success/failure based on if the
value is < -MAX_ERRNO.  This works for arches like x86 which do not use a
separate mechanism to indicate syscall failure.

We make both the is_syscall_success() and regs_return_value() static inlines
instead of macros.  The reason is because the audit function must take a void*
for the regs.  (uml calls theirs struct uml_pt_regs instead of just struct
pt_regs so audit_syscall_exit can't take a struct pt_regs).  Since the audit
function takes a void* we need to use static inlines to cast it back to the
arch correct structure to dereference it.

The other major change is that on some arches, like ia64, MIPS and ppc, we
change regs_return_value() to give us the negative value on syscall failure.
THE only other user of this macro, kretprobe_example.c, won't notice and it
makes the value signed consistently for the audit functions across all archs.

In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old
audit code as the return value.  But the ptrace_64.h code defined the macro
regs_return_value() as regs[3].  I have no idea which one is correct, but this
patch now uses the regs_return_value() function, so it now uses regs[3].

For powerpc we previously used regs->result but now use the
regs_return_value() function which uses regs->gprs[3].  regs->gprs[3] is
always positive so the regs_return_value(), much like ia64 makes it negative
before calling the audit code when appropriate.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion]
Acked-by: Tony Luck <tony.luck@intel.com> [for ia64]
Acked-by: Richard Weinberger <richard@nod.at> [for uml]
Acked-by: David S. Miller <davem@davemloft.net> [for sparc]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
2012-01-17 16:16:56 -05:00
Linus Torvalds 376613e81d Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, tsc: Skip TSC synchronization checks for tsc=reliable
  clocksource: Convert tcb_clksrc to use clocksource_register_hz/khz
  clocksource: cris: Convert to clocksource_register_khz
  clocksource: xtensa: Convert to clocksource_register_hz/khz
  clocksource: um: Convert to clocksource_register_hz/khz
  clocksource: parisc: Convert to clocksource_register_hz/khz
  clocksource: m86k: Convert to clocksource_register_hz/khz
  time: x86: Replace LATCH with PIT_LATCH in i8253 clocksource driver
  time: x86: Remove CLOCK_TICK_RATE from acpi_pm clocksource driver
  time: x86: Remove CLOCK_TICK_RATE from mach_timer.h
  time: x86: Remove CLOCK_TICK_RATE from tsc code
  time: Fix spelling mistakes in new comments
  time: fix bogus comment in timekeeping_get_ns_raw
2012-01-06 13:57:44 -08:00
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
Thomas Gleixner 0518469d0a Merge branch 'fortglx/3.3/tip/timers/core' of git://git.linaro.org/people/jstultz/linux into timers/core 2011-12-05 22:13:49 +01:00
John Stultz 60d687e7d4 clocksource: um: Convert to clocksource_register_hz/khz
This converts the um clocksource to use clocksource_register_hz/khz

This is untested, so any assistance in testing would be appreciated!

CC: Jeff Dike <jdike@addtoit.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
2011-11-21 19:01:03 -08:00
Al Viro 73395a0002 um: distribute exports to where exported stuff is defined
ksyms.c is down to the stuff defined in various USER_OBJS

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:36 +01:00
Al Viro 4d211093e8 um: fix gcov build breakage
a) exports in gmon_syms.c duplicate kernel/gcov/* ones
b) excluding -pg in vdso compile is not enough - -fprofile-arcs
and -ftest-coverage also needs to be excluded

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:26 +01:00
Al Viro 445c5786c9 um: kill shared/tlb.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:10 +01:00
Al Viro c75d053b70 um: make flush_tlb_kernel_range_common() static
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:09 +01:00
Al Viro 549e78db94 um: make load_initrd() static, kill shared/initrd.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:06 +01:00
Al Viro adcfb9852d um: kill includes of sysdep/sigcontext.h from stuff built with kernel headers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:14:54 +01:00
Al Viro 5d40de0f6e um: kill dead code around uaccess
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:14:52 +01:00
Al Viro 078073a3d4 um: -include user.h for USER_OBJ, trim includes
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:14:44 +01:00
Al Viro f2833aef6a um: clean arch_ptrace() up a bit
1) take subarch-specific stuff to subarch_ptrace()
2) PTRACE_{PEEK,POKE}{TEXT,DATA} is handled by ptrace_request() just fine...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14 18:09:37 -07:00
Ingo van Lil fbfe9c847e um: Save FPU registers between task switches
Some time ago Jeff prepared 42daba3165 ("uml: stop saving process FP
state") for UML to stop saving the process FP state between task
switches.  The assumption was that since with SKAS0 every guest process
runs inside a host process context the host OS will take care of keeping
the proper FP state.

Unfortunately this is not true for multi-threaded applications, where
all guest threads share a single host process context yet all may use
the FPU on their own.  Although I haven't verified it I suspect things
to be even worse in SKAS3 mode where all guest processes run inside a
single host process.

The patch reintroduces the saving and restoring of the FP context
between task switches.

[richard@nod.at: Ingo posted this patch in 2009, sadly it was never applied
and got lost. Now in 2011 the problem was reported by Gunnar.]

Signed-off-by: Ingo van Lil <inguin@gmx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Reported-by: <gunnarlindroth@hotmail.com>
Tested-by: <gunnarlindroth@hotmail.com>
Cc: Stanislav Meduna <stano@meduna.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14 18:09:37 -07:00
Richard Weinberger f1c93e4946 um: remove dead code
GCC 4.6's -Wunused-but-set-variable found some dead code.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:13 -07:00
Mathias Krause c0ce5b6734 um, exec: remove redundant set_fs(USER_DS)
The address limit is already set in flush_old_exec() so this
set_fs(USER_DS) is redundant.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:12 -07:00
Richard Weinberger 3ef6130ab2 um: print info about fatal segfaults
Print a short info about fatal segfaults like other archs do.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:41 -07:00
Richard Weinberger d634f194d4 um: add earlyprintk support
User Mode Linux can also benefit from earlyprintk.  UML's earlyprintk
writes kernel messages directly to stdout.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:41 -07:00
Peter Zijlstra 1c39517696 mm: now that all old mmu_gather code is gone, remove the storage
Fold all the mmu_gather rework patches into one for submission

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:16 -07:00
Peter Zijlstra 184748cc50 sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()
For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.

In order to do so we need a generic callback from the existing scheduler IPI.

This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.

BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
2011-04-14 08:52:32 +02:00
Thomas Gleixner df31a0a06f um: Use generic show_interrupts()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-24 20:35:57 +01:00