This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code. It does the following
things:
- consolidates and enhances the spinlock/rwlock debugging code
- simplifies the asm/spinlock.h files
- encapsulates the raw spinlock type and moves generic spinlock
features (such as ->break_lock) into the generic code.
- cleans up the spinlock code hierarchy to get rid of the spaghetti.
Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c. (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)
Also, i've enhanced the rwlock debugging facility, it will now track
write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.
The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:
include/asm-i386/spinlock_types.h | 16
include/asm-x86_64/spinlock_types.h | 16
I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:
SMP | UP
----------------------------|-----------------------------------
asm/spinlock_types_smp.h | linux/spinlock_types_up.h
linux/spinlock_types.h | linux/spinlock_types.h
asm/spinlock_smp.h | linux/spinlock_up.h
linux/spinlock_api_smp.h | linux/spinlock_api_up.h
linux/spinlock.h | linux/spinlock.h
/*
* here's the role of the various spinlock/rwlock related include files:
*
* on SMP builds:
*
* asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
* initializers
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
* implementations, mostly inline assembly code
*
* (also included on UP-debug builds:)
*
* linux/spinlock_api_smp.h:
* contains the prototypes for the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*
* on UP builds:
*
* linux/spinlock_type_up.h:
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* linux/spinlock_up.h:
* contains the __raw_spin_*()/etc. version of UP
* builds. (which are NOPs on non-debug, non-preempt
* builds)
*
* (included on UP-non-debug builds:)
*
* linux/spinlock_api_up.h:
* builds the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*/
All SMP and UP architectures are converted by this patch.
arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.
From: Grant Grundler <grundler@parisc-linux.org>
Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
Builds 32-bit SMP kernel (not booted or tested). I did not try to build
non-SMP kernels. That should be trivial to fix up later if necessary.
I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids
some ugly nesting of linux/*.h and asm/*.h files. Those particular locks
are well tested and contained entirely inside arch specific code. I do NOT
expect any new issues to arise with them.
If someone does ever need to use debug/metrics with them, then they will
need to unravel this hairball between spinlocks, atomic ops, and bit ops
that exist only because parisc has exactly one atomic instruction: LDCW
(load and clear word).
From: "Luck, Tony" <tony.luck@intel.com>
ia64 fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There were three changes necessary in order to allow
sparc64 to use setup-res.c:
1) Sparc64 roots the PCI I/O and MEM address space using
parent resources contained in the PCI controller structure.
I'm actually surprised no other platforms do this, especially
ones like Alpha and PPC{,64}. These resources get linked into the
iomem/ioport tree when PCI controllers are probed.
So the hierarchy looks like this:
iomem --|
PCI controller 1 MEM space --|
device 1
device 2
etc.
PCI controller 2 MEM space --|
...
ioport --|
PCI controller 1 IO space --|
...
PCI controller 2 IO space --|
...
You get the idea. The drivers/pci/setup-res.c code allocates
using plain iomem_space and ioport_space as the root, so that
wouldn't work with the above setup.
So I added a pcibios_select_root() that is used to handle this.
It uses the PCI controller struct's io_space and mem_space on
sparc64, and io{port,mem}_resource on every other platform to
keep current behavior.
2) quirk_io_region() is buggy. It takes in raw BUS view addresses
and tries to use them as a PCI resource.
pci_claim_resource() expects the resource to be fully formed when
it gets called. The sparc64 implementation would do the translation
but that's absolutely wrong, because if the same resource gets
released then re-claimed we'll adjust things twice.
So I fixed up quirk_io_region() to do the proper pcibios_bus_to_resource()
conversion before passing it on to pci_claim_resource().
3) I was mistakedly __init'ing the function methods the PCI controller
drivers provide on sparc64 to implement some parts of these
routines. This was, of course, easy to fix.
So we end up with the following, and that nasty SPARC64 makefile
ifdef in drivers/pci/Makefile is finally zapped.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some PCI devices (e.g. 3c905B, 3c556B) lose all configuration
(including BARs) when transitioning from D3hot->D0. This leaves such
a device in an inaccessible state. The patch below causes the BARs
to be restored when enabling such a device, so that its driver will
be able to access it.
The patch also adds pci_restore_bars as a new global symbol, and adds a
correpsonding EXPORT_SYMBOL_GPL for that.
Some firmware (e.g. Thinkpad T21) leaves devices in D3hot after a
(re)boot. Most drivers call pci_enable_device very early, so devices
left in D3hot that lose configuration during the D3hot->D0 transition
will be inaccessible to their drivers.
Drivers could be modified to account for this, but it would
be difficult to know which drivers need modification. This is
especially true since often many devices are covered by the same
driver. It likely would be necessary to replicate code across dozens
of drivers.
The patch below should trigger only when transitioning from D3hot->D0
(or at boot), and only for devices that have the "no soft reset" bit
cleared in the PM control register. I believe it is safe to include
this patch as part of the PCI infrastructure.
The cleanest implementation of pci_restore_bars was to call
pci_update_resource. Unfortunately, that does not currently exist
for the sparc64 architecture. The patch below includes a null
implemenation of pci_update_resource for sparc64.
Some have expressed interest in making general use of the the
pci_restore_bars function, so that has been exported to GPL licensed
modules.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since GCC has to emit a call and a delay slot to the
out-of-line "membar" routines in arch/sparc64/lib/mb.S
it is much better to just do the necessary predicted
branch inline instead as:
ba,pt %xcc, 1f
membar #whatever
1:
instead of the current:
call membar_foo
dslot
because this way GCC is not required to allocate a stack
frame if the function can be a leaf function.
This also makes this bug fix easier to backport to 2.4.x
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch contains the sparc64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
64 bit architectures all implement their own compatibility sys_open(),
when in fact the difference is simply not forcing the O_LARGEFILE
flag. So use the a common function instead.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch cleans up a commonly repeated set of changes to the NTP state
variables by adding two helper inline functions:
ntp_clear(): Clears the ntp state variables
ntp_synced(): Returns 1 if the system is synced with a time server.
This was compile tested for alpha, arm, i386, x86-64, ppc64, s390, sparc,
sparc64.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Need to use compat struct sizes and compat_sys_ioctl().
Reported by Adrian Bunk via kernel bugzilla #2683
Signed-off-by: David S. Miller <davem@davemloft.net>
We can put the __softirq_pending mask in the cpudata,
no need for the silly NR_CPUS array in kernel/softirq.c
Signed-off-by: David S. Miller <davem@davemloft.net>
It appears that a memory barrier soon after a mispredicted
branch, not just in the delay slot, can cause the hang
condition of this cpu errata.
So move them out-of-line, and explicitly put them into
a "branch always, predict taken" delay slot which should
fully kill this problem.
Signed-off-by: David S. Miller <davem@davemloft.net>
When the spinlock routines were moved out of line into
kernel/spinlock.c this made it so that the debugging
spinlocks record lock acquisition program counts in the
kernel/spinlock.c functions not in their callers.
This makes the debugging info kind of useless.
So record the correct caller's program counter and
now this feature is useful once more.
Signed-off-by: David S. Miller <davem@davemloft.net>
Removed sparc64 architecture specific users of asm/segment.h and
asm-sparc64/segment.h itself
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current uncorrectable error handling was poor enough
that the processor could just loop taking the same
trap over and over again. Fix things up so that we
at least get a log message and perhaps even some register
state.
In the process, much consolidation became possible,
particularly with the correctable error handler.
Prefix assembler and C function names with "spitfire"
to indicate that these are for Ultra-I/II/IIi/IIe only.
More work is needed to make these routines robust and
featureful to the level of the Ultra-III error handlers.
Signed-off-by: David S. Miller <davem@davemloft.net>
Verify we really are taking a data access exception trap, at TL1, from
one of the window spill/fill handlers.
Else call a new function, data_access_exception_tl1, to log the error.
Signed-off-by: David S. Miller <davem@davemloft.net>
1) Read ASI_IMMU SFSR not ASI_DMMU.
2) IMMU has no SFAR, read TPC instead
3) Delete old and incorrect comment about the DTLB protection
trap having a dependency on the SFSR contents in order to
function correctly
Signed-off-by: David S. Miller <davem@davemloft.net>
It has been reported that the way Linux handles NODEFER for signals is
not consistent with the way other Unix boxes handle it. I've written a
program to test the behavior of how this flag affects signals and had
several reports from people who ran this on various Unix boxes,
confirming that Linux seems to be unique on the way this is handled.
The way NODEFER affects signals on other Unix boxes is as follows:
1) If NODEFER is set, other signals in sa_mask are still blocked.
2) If NODEFER is set and the signal is in sa_mask, then the signal is
still blocked. (Note: this is the behavior of all tested but Linux _and_
NetBSD 2.0 *).
The way NODEFER affects signals on Linux:
1) If NODEFER is set, other signals are _not_ blocked regardless of
sa_mask (Even NetBSD doesn't do this).
2) If NODEFER is set and the signal is in sa_mask, then the signal being
handled is not blocked.
The patch converts signal handling in all current Linux architectures to
the way most Unix boxes work.
Unix boxes that were tested: DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU
3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX.
* NetBSD was the only other Unix to behave like Linux on point #2. The
main concern was brought up by point #1 which even NetBSD isn't like
Linux. So with this patch, we leave NetBSD as the lonely one that
behaves differently here with #2.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
pcibios_bus_to_resource is exported on all architectures except ia64
and sparc. Add exports for the two missing architectures. Needed when
Yenta socket support is compiled as a module.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
GCC 4.x really dislikes the games we are playing in
unaligned.c, and the cleanest way to fix this is to
move things into assembler.
Noted by Al Viro.
Signed-off-by: David S. Miller <davem@davemloft.net>
Revert commit fec59a711e, which is
breaking sparc64 that doesn't have a working pci_update_resource.
We'll re-do this after 2.6.13 when we'll do it all properly.
Some PCI devices (e.g. 3c905B, 3c556B) lose all configuration
(including BARs) when transitioning from D3hot->D0. This leaves such
a device in an inaccessible state. The patch below causes the BARs
to be restored when enabling such a device, so that its driver will
be able to access it.
The patch also adds pci_restore_bars as a new global symbol, and adds a
correpsonding EXPORT_SYMBOL_GPL for that.
Some firmware (e.g. Thinkpad T21) leaves devices in D3hot after a
(re)boot. Most drivers call pci_enable_device very early, so devices
left in D3hot that lose configuration during the D3hot->D0 transition
will be inaccessible to their drivers.
Drivers could be modified to account for this, but it would
be difficult to know which drivers need modification. This is
especially true since often many devices are covered by the same
driver. It likely would be necessary to replicate code across dozens
of drivers.
The patch below should trigger only when transitioning from D3hot->D0
(or at boot), and only for devices that have the "no soft reset" bit
cleared in the PM control register. I believe it is safe to include
this patch as part of the PCI infrastructure.
The cleanest implementation of pci_restore_bars was to call
pci_update_resource. Unfortunately, that does not currently exist
for the sparc64 architecture. The patch below includes a null
implemenation of pci_update_resource for sparc64.
Some have expressed interest in making general use of the the
pci_restore_bars function, so that has been exported to GPL licensed
modules.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
machine_restart, machine_halt and machine_power_off are machine
specific hooks deep into the reboot logic, that modules
have no business messing with. Usually code should be calling
kernel_restart, kernel_halt, kernel_power_off, or
emergency_restart. So don't export machine_restart,
machine_halt, and machine_power_off so we can catch buggy users.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These two bits were accesses non-atomically from assembler
code. So, in order to eliminate any potential races resulting
from that, move these pieces of state into two bytes elsewhere
in struct thread_info.
Signed-off-by: David S. Miller <davem@davemloft.net>
It is only used by some localized code in irq.c, and also
delete enable_prom_timer() as that is totally unused.
Signed-off-by: David S. Miller <davem@davemloft.net>
arch/sparc64/kernel/smp.c:48: error: parse error before "__attribute__"
arch/sparc64/kernel/smp.c:49: error: parse error before "__attribute__"
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also fix a bug in 32-bit syscall tracing. We forgot to update
this code when we moved over to the convention that all 32-bit
syscall arguments are zero extended by default.
Signed-off-by: David S. Miller <davem@davemloft.net>
The following renames arch_init, a kprobes function for performing any
architecture specific initialization, to arch_init_kprobes in order to
cleanup the namespace.
Also, this patch adds arch_init_kprobes to sparc64 to fix the sparc64 kprobes
build from the last return probe patch.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use macro instead of magic value for Tomatillo discard-
timeout interrupt enable register bit.
Leave OBP programming PTO value unless Tomatillo and
version >= 0x2.
If no-bus-parking property is present, explicitly clear
PCICTRL_PARK bit.
Signed-off-by: David S. Miller <davem@davemloft.net>
This was the main impetus behind adding the PCI IRQ shim.
In order to properly order DMA writes wrt. interrupts, you have to
write to a PCI controller register, then poll for that bit clearing.
There is one bit for each interrupt source, and setting this register
bit tells Tomatillo to drain all pending DMA from that device.
Furthermore, Tomatillo's with revision less than 4 require us to do a
block store due to some memory transaction ordering issues it has on
JBUS.
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows a PCI controller to shim into IRQ delivery
so that DMA queues can be drained, if necessary.
If some bus specific code needs to run before an IRQ
handler is invoked, the bus driver simply needs to setup
the function pointer in bucket->irq_info->pre_handler and
the two args bucket->irq_info->pre_handler_arg[12].
The Schizo PCI driver is converted over to use a pre-handler
for the DMA write-sync processing it needs when a device
is behind a PCI->PCI bus deeper than the top-level APB
bridges.
While we're here, clean up all of the action allocation
and handling. Now, we allocate the irqaction as part of
the bucket->irq_info area. There is an array of 4 irqaction
(for PCI irq sharing) and a bitmask saying which entries
are active.
The bucket->irq_info is allocated at build_irq() time, not
at request_irq() time. This simplifies request_irq() and
free_irq() tremendously.
The SMP dynamic IRQ retargetting code got removed in this
change too. It was disabled for a few months now, and we
can resurrect it in the future if we want.
Signed-off-by: David S. Miller <davem@davemloft.net>
The only real user was the assembler floppy interrupt
handler, which does not need to be in assembly.
This makes it so that there are less pieces of code which
know about the internal layout of ivector_table[] and
friends.
Signed-off-by: David S. Miller <davem@davemloft.net>
In particular, avoid membar instructions in the delay
slot of a jmpl instruction.
UltraSPARC-I, II, IIi, and IIe have a bug, documented in
the UltraSPARC-IIi User's Manual, Appendix K, Erratum 51
The long and short of it is that if the IMU unit misses
on a branch or jmpl, and there is a store buffer synchronizing
membar in the delay slot, the chip can stop fetching instructions.
If interrupts are enabled or some other trap is enabled, the
chip will unwedge itself, but performance will suffer.
We already had a workaround for this bug in a few spots, but
it's better to have the entire tree sanitized for this rule.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is based on work by Carlos O'Donell and Matthew Wilcox. It
introduces/updates the compat_time_t type and uses it for compat siginfo
structures. I have built this on ppc64 and x86_64.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch includes sparc64 architecture specific changes to support temporary
disarming on reentrancy of probes.
Signed-of-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
