Commit Graph

106996 Commits

Author SHA1 Message Date
Adrian Bunk 175fb09f4a sh: make EARLY_PCI_OP's static
This patch makes the needlessly global EARLY_PCI_OP's static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:30 +09:00
Adrian Bunk 2b7bf930ae sh/boards/dreamcast/rtc.c: make 2 functions static
This patch makes the needlessly global aica_rtc_{get,set}timeofday()
static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:30 +09:00
Adrian McMenamin 306cfd630a maple: tidy maple_driver code by removing redundant connect/disconnect
The connect and disconnect functions are unnecessary - everything they do can be
accomplished in the initial probe - so remove them.

Signed-off-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:30 +09:00
Nobuhiro Iwamatsu 4cec1a37ba sh: Renesas Solutions SH7763RDP board support
This patch adds basic support for the SH7763RDP board.
This supports a basic stuff provided in SH7763, like SCIF,
NOR Flash and USB host.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:30 +09:00
Nobuhiro Iwamatsu c63847a362 sh: Add SCIF2 support for SH7763.
SH7763 has 3 SCIF device. Current code supports SCIF0 and 1.
SCIF0 and 1 are same register constitution, but only SCIF2 is different.
I added support of SCIF2.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:29 +09:00
Yusuke Goda 04e917b606 sh: Add support Renesas Solutions AP-325RXA board
This board is SH7723 base board.

This has SCIF, LCDC, USB Host controler, NOR/NAND Flash, Sound,
Ether and other.

This patch supports SCIF, NOR Flash.

Signed-off-by: Yusuke Goda <goda.yusuke@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:29 +09:00
Paul Mundt 42fd3b142d sh: Initial consolidation of the _32/_64 uaccess split.
This consolidates everything but the bare assembly routines, which we
will sync up in a follow-up patch.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:29 +09:00
Paul Mundt 31f6a11fe7 sh: Consolidate addr/access_ok across mmu/nommu on 32bit.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:29 +09:00
Paul Mundt 85247285ea sh: Use the common segment definitions for the _64 uaccess routines.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:29 +09:00
Paul Mundt 66dfe18114 sh: Add support for 16kB PAGE_SIZE.
16kB is a useful size on nommu, while 64kB still tends to be too big to
be useful. Newer MMUs are likely to support this as well, so plug it
in in anticipation of those, too.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:29 +09:00
Paul Mundt 74fcc77982 sh: Support variable page sizes on nommu.
PAGE_SIZE doesn't need to be fixed at 4096 on nommu, so stub in a !MMU
case for the various PAGE_SIZE Kconfig options.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:28 +09:00
Paul Mundt 02f7e627f9 sh: Consolidate segment modifiers across mmu/nommu systems.
This moves get_fs/set_fs() and friends in to asm/segment.h. The
mm_segment_t definition is likewise consolidated from the _32/_64 split.

This is prepatory groundwork for using the generic address space limit
and verification routines across mmu/nommu configs.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:28 +09:00
Paul Mundt 3787aa112c sh: RSK+ 7203 board support.
This adds initial support for the RTE RSK+ SH7203 board.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:28 +09:00
Paul Mundt 2cd1e31859 sh: Make dump_task dependent on ELF core.
Currently this is only linked in for CONFIG_BINFMT_ELF, make it dependent
on CONFIG_ELF_CORE, so it's both selectable there and also linked in for
CONFIG_BINFMT_ELF_FDPIC.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:28 +09:00
Paul Mundt 3bc24a1a54 sh: Initial ELF FDPIC support.
This adds initial support for ELF FDPIC on MMU-less SH, as per version
0.2 of the ABI definition at:

	http://www.codesourcery.com/public/docs/sh-fdpic/sh-fdpic-abi.txt

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:28 +09:00
Paul Mundt 9b14ec35f0 binfmt_elf_fdpic: Magical stack pointer index, for NEW_AUX_ENT compat.
While implementing binfmt_elf_fdpic on SH it quickly became apparent
that SH was the first platform to support both binfmt_elf_fdpic and
binfmt_elf, as well as the only of the FDPIC platforms to make use of the
auxvt.

Currently binfmt_elf_fdpic uses a special version of NEW_AUX_ENT() where
the first argument is the entry displacement after csp has been adjusted,
being reset after each adjustment. As we have no ability to sort this out
through the platform's ARCH_DLINFO, this index needs to be managed
entirely in create_elf_fdpic_tables(). Presently none of the platforms
that set their own auxvt entries are able to do so through their
respective ARCH_DLINFOs when using binfmt_elf_fdpic.

In addition to this, binfmt_elf_fdpic has been looking at
DLINFO_ARCH_ITEMS for the number of architecture-specific entries in the
auxvt. This is legacy cruft, and is not defined by any platforms in-tree,
even those that make heavy use of the auxvt. AT_VECTOR_SIZE_ARCH is
always available, and contains the number that is of interest here, so we
switch to using that unconditionally as well.

As this has direct bearing on how much stack is used, platforms that have
configurable (or dynamically adjustable) NEW_AUX_ENT calls need to either
make AT_VECTOR_SIZE_ARCH more fine-grained, or leave it as a worst-case
and live with some lost stack space if those entries aren't pushed (some
platforms may also need to purposely sacrifice some space here for
alignment considerations, as noted in the code -- although not an issue
for any FDPIC-capable platform today).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: David Howells <dhowells@redhat.com>
2008-07-28 18:10:28 +09:00
Adrian Bunk e3b0860090 move arch/sh/lib/io.o to obj-y
EXPORT_SYMBOL's in lib-y considered harmful:

<--  snip  -->

...
  MODPOST 1837 modules
ERROR: "__raw_readsl" [drivers/ssb/ssb.ko] undefined!
ERROR: "__raw_writesl" [drivers/ssb/ssb.ko] undefined!
ERROR: "__raw_writesl" [drivers/net/smc91x.ko] undefined!
ERROR: "__raw_readsl" [drivers/net/smc91x.ko] undefined!
ERROR: "__raw_writesl" [drivers/net/3c59x.ko] undefined!
ERROR: "__raw_readsl" [drivers/net/3c59x.ko] undefined!
...
make[2]: *** [__modpost] Error 1

<--  snip  -->

Reported-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:28 +09:00
Adrian Bunk 7223ce29e8 sh dreamcast: export board_pci_channels
This patch fixes the following build error:

<--  snip  -->

...
  MODPOST 1837 modules
ERROR: "board_pci_channels" [drivers/pcmcia/yenta_socket.ko] undefined!
...
make[2]: *** [__modpost] Error 1

<--  snip  -->

I freely admit that it's a pathological configuration, but as long as
it is allowed it should build.

Reported-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:27 +09:00
Adrian Bunk b19a33caba sh: export get_cpu_subtype
This patch fixes the following build error:

<--  snip  -->

...
  MODPOST 1837 modules
ERROR: "get_cpu_subtype" [arch/sh/oprofile/oprofile.ko] undefined!
...
make[2]: *** [__modpost] Error 1

<--  snip  -->

Reported-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:27 +09:00
Khem Raj 82706b8f7b sh: Prevent leaking of CONFIG_SUPERH32 to userspace in asm/unistd.h.
CONFIG_SUPERH32 is currently trickling into userspace unistd.h. Attached
patch uses __SH5__ define in userspace.

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:27 +09:00
Li Zefan 45dabf1427 sh: fix seq_file memory leak
When using single_open(), single_release() should be used instead
of seq_release(), otherwise there is a memory leak.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:27 +09:00
Benjamin Herrenschmidt 00df438e89 powerpc: Disable 64K hugetlb support when doing 64K SPU mappings
The 64K SPU local store mapping feature is incompatible with the
64K huge pages support due to the inability of some parts of
the memory management to differenciate between them while they
use a different page table format.

For now, disable 64K huge pages when CONFIG_SPU_FS_64K_LS,
in the long run, this can be fixed by making this feature use
the hugetlb page table format.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:53 +10:00
Benjamin Herrenschmidt 025d7917a5 powerpc/powermac: Fixup default serial port device for pmac_zilog
This removes the non-working code in legacy_serial that tried to handle
the powermac SCC ports, and instead add a (now working) function to the
powermac platform code to find the default serial console if any.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:53 +10:00
Benjamin Herrenschmidt f023bf0f91 powerpc/powermac: Use sane default baudrate for SCC debugging
When using the "sccdbg" option to route early kernel messages and
xmon to the SCC serial port on PowerMacs, when this wasn't the
configured output port of Open Firmware, we initialize the baudrate
to 57600bps. This isn't a very good default on some powermacs where
both the FW and pmac_zilog will default to 38400. This fixes it to
use the same logic as pmac_zilog to pick a default speed.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:52 +10:00
Nick Piggin 83ac6a1ed4 powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 64-bit
Implement _PAGE_SPECIAL and pte_special() for 64-bit powerpc. This bit will
be used by the fast get_user_pages() to differenciate PTEs that correspond
to a valid struct page from special mappings that don't such as IO mappings
obtained via io_remap_pfn_ranges().

Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Reviewed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:52 +10:00
Nathan Lynch 124c27d375 powerpc: Show processor cache information in sysfs
Collect cache information from the OF device tree and display it in
the cpu hierarchy in sysfs.  This is intended to be compatible at the
userspace level with x86's implementation[1], hence some of the funny
attribute names.  The arrangement of cache info is not immediately
intuitive, but (again) it's for compatibility's sake.

The cache attributes exposed are:

type (Data, Instruction, or Unified)
level (1, 2, 3...)
size
coherency_line_size
number_of_sets
ways_of_associativity

All of these can be derived on platforms that follow the OF PowerPC
Processor binding.  The code "publishes" only those attributes for
which it is able to determine values; attributes for values which
cannot be determined are not created at all.

[1] arch/x86/kernel/cpu/intel_cacheinfo.c

BenH: Turned some printk's into pr_debug, added better NULL checking
in a couple of places.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:52 +10:00
Nathan Lynch e9efed3b80 powerpc: Make core id information available to userspace
Existing Open Firmware practice is to report each processor core as a
separate node in the device tree.  Report the value of the "reg" OF
property corresponding to a logical CPU's device node as the core_id
attribute in /sys/devices/system/cpu/cpu*/topology/core_id.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:52 +10:00
Nathan Lynch 440a0857e3 powerpc: Make core sibling information available to userspace
Implement the notion of "core siblings" for powerpc.  This makes
/sys/devices/system/cpu/cpu*/topology/core_siblings present sensible
values, indicating online CPUs which share an L2 cache.

BenH: Made cpu_to_l2cache() use of_find_node_by_phandle() instead
of IBM-specific open coded search

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:51 +10:00
Stephen Rothwell 0764bf63da powerpc/vio: More fallout from dma_mapping_error API change
arch/powerpc/kernel/vio.c:533: error: too few arguments to function 'dma_mapping_error'

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:51 +10:00
Stephen Rothwell c713e7cbfa ibmveth: Fix multiple errors with dma_mapping_error conversion
The addition of an argument to dma_mapping_error() in commit
8d8bb39b9e "dma-mapping: add the device
argument to dma_mapping_error()" left a bit of fallout:

drivers/net/ibmveth.c:263: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:264: error: expected ')' before 'goto'
drivers/net/ibmveth.c:284: error: expected expression before '}' token
drivers/net/ibmveth.c:297: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:298: error: expected ')' before 'dma_unmap_single'
drivers/net/ibmveth.c:306: error: expected expression before '}' token
drivers/net/ibmveth.c:491: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:927: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:927: error: expected ')' before '{' token
drivers/net/ibmveth.c:974: error: expected expression before '}' token
drivers/net/ibmveth.c:914: error: label 'out' used but not defined m

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:51 +10:00
Stephen Rothwell 3cee67f779 powerpc/pseries: Fix CMO sysdev attribute API change fallout
Noticed due to these wanings:

arch/powerpc/platforms/pseries/cmm.c:298: warning: initialization from incompatible pointer type
arch/powerpc/platforms/pseries/cmm.c:299: warning: initialization from incompatible pointer type
arch/powerpc/platforms/pseries/cmm.c:320: warning: initialization from incompatible pointer type
arch/powerpc/platforms/pseries/cmm.c:320: warning: initialization from incompatible pointer type

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:50 +10:00
Roland McGrath dec2b0d0cc powerpc: Enable tracehook for the architecture
The powerpc arch code has all the prerequisites, so set HAVE_ARCH_TRACEHOOK.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:50 +10:00
Roland McGrath 7d6d637dac powerpc: Add TIF_NOTIFY_RESUME support for tracehook
This adds TIF_NOTIFY_RESUME support for powerpc.  When set,
we call tracehook_notify_resume() on the way to user mode.
This overloads do_signal() to do the work, but changes its
arguments to it has the TIF_* bits handy in a register and
drops the useless first argument that was always zero.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:50 +10:00
Roland McGrath f1ba12856b powerpc: Add asm/syscall.h with the tracehook entry points
Add asm/syscall.h for powerpc with all the required entry points.
This will allow arch-independent tracing code for system calls.

BenH: Fixed up use of regs->trap to properly mask low bit

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:49 +10:00
Roland McGrath 4f72c4279e powerpc: Make syscall tracing use tracehook.h helpers
This changes powerpc syscall tracing to use the new tracehook.h entry
points.  There is no change, only cleanup.

In addition, the assembly changes allow do_syscall_trace_enter() to
abort the syscall without losing the information about the original
r0 value.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:49 +10:00
Roland McGrath 6558ba2b5c powerpc: Call tracehook_signal_handler() when setting up signal frames
This makes the powerpc signal handling code call tracehook_signal_handler()
after a handler is set up.  This means that using PTRACE_SINGLESTEP to
enter a signal handler will report to ptrace on the first instruction of
the handler, instead of the second.  This is consistent with what x86 and
other machines do, and what users and debuggers want.

BenH: Fixed up the test for the trap value.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:49 +10:00
Nathan Lynch e2075f79a9 powerpc: Update cpu_sibling_maps dynamically
Rather doing one initialization pass over all the per-cpu
cpu_sibling_maps at boot, update the maps at cpu online/offline time.

This is a behavior change -- the thread_siblings attribute now
reflects only online siblings, whereas it would display offline
siblings before.  The new behavior matches that of x86, and is
arguably more useful.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:49 +10:00
Nathan Lynch 9ba1984ead powerpc: register_cpu_online should be __cpuinit
It is called only in cpu online paths.

(caught by CONFIG_DEBUG_SECTION_MISMATCH=y)

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:48 +10:00
Nathan Lynch 7d2f6075f9 powerpc: kill useless SMT code in prom_hold_cpus
This piece of code is broken for >2 threads, and possibly in some
other subtle ways (such as comparing a value obtained from an
"ibm,ppc-interrupt-server#s" property to a value obtained from a
"reg" property) and doesn't seem to have any useful purpose in the
first place other than a dubious warning in case NR_CPUS is too
small, which probably isn't the right place to do so.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:48 +10:00
Kumar Gala ff8dc7698c powerpc: Fix 8xx build failure
The 'powerpc ioremap_prot' broke 8xx builds:

include2/asm/pgtable-ppc32.h:555: error: '_PAGE_WRITETHRU' undeclared (first use in this function)
include2/asm/pgtable-ppc32.h:555: error: (Each undeclared identifier is reported only once
include2/asm/pgtable-ppc32.h:555: error: for each function it appears in.)

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:48 +10:00
Nathan Lynch b9fa49a9a9 powerpc: Fix vio build warnings
arch/powerpc/kernel/vio.c:1034: warning: function declaration isn’t a prototype
arch/powerpc/kernel/vio.c:1035: warning: function declaration isn’t a prototype

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:47 +10:00
Kumar Gala 2325f0a0c3 powerpc/booke: Clean up the hardware watchpoint support
* CONFIG_BOOKE is selected by CONFIG_44x so we dont need both
* Fixed a few comments
* Go back to only using DBCR0_IDM to determine if we are using
  debug resources.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:47 +10:00
Huang Weiyi d3b060231b powerpc: Removed duplicated include in stacktrace.c
Removed duplicated include file <linux/module.h> in
arch/powerpc/kernel/stacktrace.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-28 16:30:47 +10:00
Benjamin Herrenschmidt d65d830ca0 Merge commit 'gcl/gcl-next' 2008-07-28 16:30:40 +10:00
Rusty Russell 784e2d7600 stop_machine: fix up ftrace.c
Simple conversion.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Abhishek Sagar <sagar.abhishek@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
2008-07-28 12:16:31 +10:00
Rusty Russell 9b1a4d3837 stop_machine: Wean existing callers off stop_machine_run()
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-28 12:16:31 +10:00
Rusty Russell eeec4fad96 stop_machine(): stop_machine_run() changed to use cpu mask
Instead of a "cpu" arg with magic values NR_CPUS (any cpu) and ~0 (all
cpus), pass a cpumask_t.  Allow NULL for the common case (where we
don't care which CPU the function is run on): temporary cpumask_t's
are usually considered bad for stack space.

This deprecates stop_machine_run, to be removed soon when all the
callers are dead.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-28 12:16:30 +10:00
Rusty Russell 0432158758 Hotplug CPU: don't check cpu_online after take_cpu_down
Akinobu points out that if take_cpu_down() succeeds, the cpu must be offline.
Remove the cpu_online() check, and put a BUG_ON().

Quoting Akinobu Mita:
   Actually the cpu_online() check was necessary before appling this
   stop_machine: simplify patch.

   With old __stop_machine_run(), __stop_machine_run() could succeed
   (return !IS_ERR(p) value) even if take_cpu_down() returned non-zero value.
   The return value of take_cpu_down() was obtained through kthread_stop()..

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Akinobu Mita" <akinobu.mita@gmail.com>
2008-07-28 12:16:29 +10:00
Rusty Russell ffdb5976c4 Simplify stop_machine
stop_machine creates a kthread which creates kernel threads.  We can
create those threads directly and simplify things a little.  Some care
must be taken with CPU hotunplug, which has special needs, but that code
seems more robust than it was in the past.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2008-07-28 12:16:29 +10:00
Jason Baron 5c2aed6225 stop_machine: add ALL_CPUS option
-allow stop_mahcine_run() to call a function on all cpus. Calling
 stop_machine_run() with a 'ALL_CPUS' invokes this new behavior.
 stop_machine_run() proceeds as normal until the calling cpu has
 invoked 'fn'. Then, we tell all the other cpus to call 'fn'.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
CC: Adrian Bunk <bunk@stusta.de>
CC: Andi Kleen <andi@firstfloor.org>
CC: Alexey Dobriyan <adobriyan@gmail.com>
CC: Christoph Hellwig <hch@infradead.org>
CC: mingo@elte.hu
CC: akpm@osdl.org
2008-07-28 12:16:28 +10:00