Move the default case out of the if, ie. when we're just displaying
an irq. And consolidate all the odd cases at the top, ie. printing
the header and footer.
And in the process cope with sparse irq_descs.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
get_irq_desc() is a powerpc-specific version of irq_to_desc(). That
is reason enough to remove it, but it also doesn't know about sparse
irq_desc support which irq_to_desc() does (when we enable it).
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds powerpc-specific tracepoints for interrupt entry and exit.
While we already have generic irq_handler_entry and irq_handler_exit
tracepoints there are cases on our virtualised powerpc machines where an
interrupt is presented to the OS, but subsequently handled by the hypervisor.
This means no OS interrupt handler is invoked.
Here is an example on a POWER6 machine with the patch below applied:
<idle>-0 [006] 3243.949840744: irq_entry: pt_regs=c0000000ce31fb10
<idle>-0 [006] 3243.949850520: irq_exit: pt_regs=c0000000ce31fb10
<idle>-0 [007] 3243.950218208: irq_entry: pt_regs=c0000000ce323b10
<idle>-0 [007] 3243.950224080: irq_exit: pt_regs=c0000000ce323b10
<idle>-0 [000] 3244.021879320: irq_entry: pt_regs=c000000000a63aa0
<idle>-0 [000] 3244.021883616: irq_handler_entry: irq=87 handler=eth0
<idle>-0 [000] 3244.021887328: irq_handler_exit: irq=87 return=handled
<idle>-0 [000] 3244.021897408: irq_exit: pt_regs=c000000000a63aa0
Here we see two phantom interrupts (no handler was invoked), followed
by a real interrupt for eth0. Without the tracepoints in this patch we
would have missed the phantom interrupts.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.
Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.
All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)
The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.
Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.
User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)
This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILES
for N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
done
FILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\<event\>/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES
... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.
Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.
( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )
Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is a random collection of added ifdef's around portions of
code that only mak sense on server processors. Using either
CONFIG_PPC_STD_MMU_64 or CONFIG_PPC_BOOK3S as seems appropriate.
This is meant to make the future merging of Book3E 64-bit support
easier.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We should no longer have any irq code that needs __do_IRQ(), so
remove the fallback to __do_IRQ().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The guts of do_IRQ() isn't really the right place to be documenting
the ppc_md.get_irq() interface. So move the comment into machdep.h
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Makes do_IRQ() shorter and clearer.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rather than a giant ifdef in the body of do_IRQ(), including a
dangling else, move the irq stack logic into a separate routine and
do the ifdef there.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Conflicts:
arch/powerpc/include/asm/systbl.h
arch/powerpc/include/asm/unistd.h
include/linux/init_task.h
Merge reason: the conflicts are non-trivial: PowerPC placement
of sys_perf_counter_open has to be mixed with the
new preadv/pwrite syscalls.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The irq remapping layer seems to cause some confusion when people
see a different irq number in /proc/interrupts vs the one they
request in their driver or DTS.
So have the irq remapping layer print out a message when we map an
irq. The message is only printed the first time the irq is mapped,
and it's KERN_DEBUG so most people won't see it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
While going over the wakeup code I noticed delayed wakeups only work
for hardware counters but basically all software counters rely on
them.
This patch unifies and generalizes the delayed wakeup to fix this
issue.
Since we're dealing with NMI context bits here, use a cmpxchg() based
single link list implementation to track counters that have pending
wakeups.
[ This should really be generic code for delayed wakeups, but since we
cannot use cmpxchg()/xchg() in generic code, I've let it live in the
perf_counter code. -- Eric Dumazet could use it to aggregate the
network wakeups. ]
Furthermore, the x86 method of using TIF flags was flawed in that its
quite possible to end up setting the bit on the idle task, loosing the
wakeup.
The powerpc method uses per-cpu storage and does appear to be
sufficient.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Orig-LKML-Reference: <20090330171023.153932974@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: build fix for powerpc
Commit bd753921015e7905 ("perf_counter: software counter event
infrastructure") introduced a use of TIF_PERF_COUNTERS into the core
perfcounter code. This breaks the build on powerpc because we use
a flag in a per-cpu area to signal wakeups on powerpc rather than
a thread_info flag, because the thread_info flags have to be
manipulated with atomic operations and are thus slower than per-cpu
flags.
This fixes the by changing the core to use an abstracted
set_perf_counter_pending() function, which is defined on x86 to set
the TIF_PERF_COUNTERS flag and on powerpc to set the per-cpu flag
(paca->perf_counter_pending). It changes the previous powerpc
definition of set_perf_counter_pending to not take an argument and
adds a clear_perf_counter_pending, so as to simplify the definition
on x86.
On x86, set_perf_counter_pending() is defined as a macro. Defining
it as a static inline in arch/x86/include/asm/perf_counters.h causes
compile failures because <asm/perf_counters.h> gets included early in
<linux/sched.h>, and the definitions of set_tsk_thread_flag etc. are
therefore not available in <asm/perf_counters.h>. (On powerpc this
problem is avoided by defining set_perf_counter_pending etc. in
<asm/hw_irq.h>.)
Signed-off-by: Paul Mackerras <paulus@samba.org>
Merge reason: we have gathered quite a few conflicts, need to merge upstream
Conflicts:
arch/powerpc/kernel/Makefile
arch/x86/ia32/ia32entry.S
arch/x86/include/asm/hardirq.h
arch/x86/include/asm/unistd_32.h
arch/x86/include/asm/unistd_64.h
arch/x86/kernel/cpu/common.c
arch/x86/kernel/irq.c
arch/x86/kernel/syscall_table_32.S
arch/x86/mm/iomap_32.c
include/linux/sched.h
kernel/Makefile
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Convert the last remaining users.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: linuxppc-dev@ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Conflicts:
arch/x86/include/asm/pda.h
We merge tip/core/percpu into tip/perfcounters/core because of a
semantic and contextual conflict: the former eliminates the PDA,
while the latter extends it with apic_perf_irqs field.
Resolve the conflict by moving the new field to the irq_cpustat
structure on 64-bit too.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, update to new cpumask API
Irq_desc.affinity and irq_desc.pending_mask are now cpumask_var_t's
so access to them should be using the new cpumask API.
Signed-off-by: Mike Travis <travis@sgi.com>
Impact: build fix
Ingo Molnar wrote:
> tip/arch/blackfin/kernel/irqchip.c: In function 'show_interrupts':
> tip/arch/blackfin/kernel/irqchip.c:85: error: 'struct kernel_stat' has no member named 'irqs'
> make[2]: *** [arch/blackfin/kernel/irqchip.o] Error 1
> make[2]: *** Waiting for unfinished jobs....
>
So could move kstat_irqs array to irq_desc struct.
(s390, m68k, sparc) are not touched yet, because they don't support genirq
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Because 64-bit powerpc uses lazy (soft) interrupt disabling, it is
possible for a performance monitor exception to come in when the
kernel thinks interrupts are disabled (i.e. when they are
soft-disabled but hard-enabled). In such a situation the performance
monitor exception handler might have some processing to do (such as
process wakeups) which can't be done in what is effectively an NMI
handler.
This provides a way to defer that work until interrupts get enabled,
either in raw_local_irq_restore() or by returning from an interrupt
handler to code that had interrupts enabled. We have a per-processor
flag that indicates that there is work pending to do when interrupts
subsequently get re-enabled. This flag is checked in the interrupt
return path and in raw_local_irq_restore(), and if it is set,
perf_counter_do_pending() is called to do the pending work.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Impact: change existing irq_chip API
Not much point with gentle transition here: the struct irq_chip's
setaffinity method signature needs to change.
Fortunately, not widely used code, but hits a few architectures.
Note: In irq_select_affinity() I save a temporary in by mangling
irq_desc[irq].affinity directly. Ingo, does this break anything?
(Folded in fix from KOSAKI Motohiro)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: jeremy@xensource.com
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
The radix trees used by interrupt controllers for their irq reverse
mapping (currently only the XICS found on pSeries) have a complex
locking scheme dating back to before the advent of the lockless radix
tree.
This takes advantage of the lockless radix tree and of the fact that
the items of the tree are pointers to a static array (irq_map)
elements which can never go under us to simplify the locking.
Concurrency between readers and writers is handled by the intrinsic
properties of the lockless radix tree. Concurrency between writers is
handled with a global mutex.
Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
irq_radix_revmap() currently serves 2 purposes, irq mapping lookup
and insertion which happen in interrupt and process context respectively.
Separate the function into its 2 components, one for lookup only and one
for insertion only.
Fix the only user of the revmap tree (XICS) to use the new functions.
Also, move the insertion into the radix tree of those irqs that were
requested before it was initialized at said tree initialization.
Mutual exclusion between the tree initialization and readers/writers is
handled via a state variable (revmap_trees_allocated) set to 1 when the tree
has been initialized and set to 2 after the already requested irqs have been
inserted in the tree by the init path. This state is checked before any reader
or writer access just like we used to check for tree.gfp_mask != 0 before.
Finally, now that we're not any longer inserting nodes into the radix-tree
in interrupt context, turn the GFP_ATOMIC allocations into GFP_KERNEL ones.
Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that arch/ppc is gone and CONFIG_PPC_MERGE is always set, remove
the dead code associated with !CONFIG_PPC_MERGE from arch/powerpc
and include/asm-powerpc.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
debugfs_create_file() returns a non-NULL (non-zero) value in case of
success, not a NULL value.
This fixes this non-critical boot-time debugging error message:
[ 1.316386] calling irq_debugfs_init+0x0/0x50
[ 1.316399] initcall irq_debugfs_init+0x0/0x50 returned -12 after 0 msecs
[ 1.316411] initcall irq_debugfs_init+0x0/0x50 returned with error code -12
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When I changed irq_alloc_host() to take an of_node
(52964f87c6: "Add an optional
device_node pointer to the irq_host"), I botched the reference
counting semantics.
Stephen pointed out that it's irq_alloc_host()'s business if
it needs to take an additional reference to the device_node,
the caller shouldn't need to care.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
For the additonal exception levels (critical, debug, machine check) on
40x/book-e we were using "static" allocations of the stack in the
associated head.S.
Move to a runtime allocation to make the code a bit easier to read as
we mimic how we handle IRQ stacks. Its also a bit easier to setup the
stack with a "dummy" thread_info in C code.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
This patch adds full support for ftrace for PowerPC (both 64 and 32 bit).
This includes dynamic tracing and function filtering.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This makes it possible to use separate stacks for hard and soft IRQs
on 32-bit powerpc as well as on 64-bit. The code for 32-bit is just
the 32-bit analog of the 64-bit code.
* Added allocation and initialization of the irq stacks. We limit the
stacks to be in lowmem for ppc32.
* Implemented ppc32 versions of call_do_softirq() and call_handle_irq()
to switch the stack pointers
* Reworked how we do stack overflow detection. We now keep around the
limit of the stack in the thread_struct and compare against the limit
to see if we've overflowed. We can now use this on ppc64 if desired.
[ paulus@samba.org: Fixed bug on 6xx where we need to reload r9 with the
thread_info pointer. ]
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds the low level irq tracing hooks to the powerpc architecture
needed to enable full lockdep functionality.
This is partly based on Johannes Berg's initial version. I removed
the asm trampoline that isn't needed (thus improving performance) and
modified all sorts of bits and pieces, reworking most of the assembly,
etc...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes the handling of the preempt count when switching
interrupt stacks so that HW interrupt properly get the softirq
mask copied over from the previous stack.
It also initializes the softirq stack preempt_count to 0 instead
of SOFTIRQ_OFFSET, like x86, as __do_softirq() does the increment,
and we hit some lockdep checks if we have it twice.
That means we do run for a little while off the softirq stack
with the preempt-count set to 0, which could be deadly if we
try to take a softirq at that point, however we do so with
interrupts disabled, so I think we are ok.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A subtle bug sneaked into iSeries recently. On this platform, we must
not normally clear MSR:EE (the hardware external interrupt enable)
except for short periods of time. Taking an interrupt while
soft-disabled doesn't cause us to clear it for example.
The iSeries kernel expects to mostly run with MSR:EE enabled at all
times except in a few exception entry/exit code paths. Thus
local_irq_enable() doesn't check if it needs to hard-enable as it
expects this to be unnecessary on iSeries.
However, hard_irq_disable() _does_ cause MSR:EE to be cleared,
including on iSeries. A call to it was recently added to the
context switch code, thus causing interrupts to become disabled
for a long periods of time, causing the iSeries watchdog to kick
in under some circumstances and other nasty things.
This patch fixes it by making local_irq_enable() properly re-enable
MSR:EE on iSeries. It basically removes a return statement here
to make iSeries use the same code path as everybody else. That does
mean that we might occasionally get spurious decrementer interrupts
but I don't think that matters.
Another option would have been to make hard_irq_disable() a nop
on iSeries but I didn't like it much, in case we have good reasons
to hard-disable.
Part of the patch is fixes to make sure the hard_enabled PACA field
is properly set on iSeries as it used not to be before, since it
was mostly unused.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (408 commits)
[POWERPC] Add memchr() to the bootwrapper
[POWERPC] Implement logging of unhandled signals
[POWERPC] Add legacy serial support for OPB with flattened device tree
[POWERPC] Use 1TB segments
[POWERPC] XilinxFB: Allow fixed framebuffer base address
[POWERPC] XilinxFB: Add support for custom screen resolution
[POWERPC] XilinxFB: Use pdata to pass around framebuffer parameters
[POWERPC] PCI: Add 64-bit physical address support to setup_indirect_pci
[POWERPC] 4xx: Kilauea defconfig file
[POWERPC] 4xx: Kilauea DTS
[POWERPC] 4xx: Add AMCC Kilauea eval board support to platforms/40x
[POWERPC] 4xx: Add AMCC 405EX support to cputable.c
[POWERPC] Adjust TASK_SIZE on ppc32 systems to 3GB that are capable
[POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers
[POWERPC] 85xx: Enable FP emulation in MPC8560 ADS defconfig
[POWERPC] 85xx: Killed <asm/mpc85xx.h>
[POWERPC] 85xx: Add cpm nodes for 8541/8555 CDS
[POWERPC] 85xx: Convert mpc8560ads to the new CPM binding.
[POWERPC] mpc8272ads: Remove muram from the CPM reg property.
[POWERPC] Make clockevents work on PPC601 processors
...
Fixed up conflict in Documentation/powerpc/booting-without-of.txt manually.
As noted by Christoph Hellwig, pktgen was the only user so
it can now be removed.
[ Add missing cases caught by Adrian Bunk. -DaveM ]
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces zalloc_maybe_bootmem and uses it so that we don't
have to mark a whole (largish) routine as __init_ref_ok.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds a debugfs file "powerpc/virq_mapping", which shows the virtual
to real mapping of irq numbers. Enable it with CONFIG_VIRQ_DEBUG.
Signed-off-by: Zhang Wei <wei.zhang@freescale.com>
Signed-off-by: Chen Gong <G.Chen@freescale.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Although no one uses the hwirq value for legacy irqs at the moment, we
should really setup the correct value in the irq_map.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The most common match semantic is an exact match based on the device node.
So provide a default implementation that does this, and hook it up if no
match routine is specified.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently if you don't specify a match callback for your irq_host it's
assumed you match everything. This is a kind of opt-out approach, and
turns out to be the exception rather than the rule.
So change the semantics to be opt-in, ie. you don't match anything unless
you provide a match callback. This in itself isn't very useful, but will
allow us to provide a default match implementation in a subsequent patch.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The majority of irq_host implementations (3 out of 4) are associated
with a device_node, and need to stash it somewhere. Rather than having
it somewhere different for each host, add an optional device_node pointer
to the irq_host structure.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fixed the following warnings:
WARNING: vmlinux.o(.text+0x2934): Section mismatch: reference to .init.text:__alloc_bootmem (between 'irq_alloc_host' and 'irq_set_default_host')
WARNING: vmlinux.o(.text+0xb2aa): Section mismatch: reference to .init.data:boot_command_line (between 'register_early_udbg_console' and 'udbg_printf')
WARNING: vmlinux.o(.text+0xb2b2): Section mismatch: reference to .init.data:boot_command_line (between 'register_early_udbg_console' and 'udbg_printf')
WARNING: vmlinux.o(.text+0xe354): Section mismatch: reference to .init.text:__alloc_bootmem (between 'pcibios_alloc_controller' and 'pci_domain_nr')
WARNING: vmlinux.o(.text+0x12768): Section mismatch: reference to .init.text:update_bridge_resource (between 'quirk_fsl_pcie_transparent' and 'indirect_read_config')
WARNING: vmlinux.o(.text+0x127a8): Section mismatch: reference to .init.text:update_bridge_resource (between 'quirk_fsl_pcie_transparent' and 'indirect_read_config')
WARNING: vmlinux.o(.text+0x17566c): Section mismatch: reference to .init.text:pcibios_fixup_bus (between 'pci_scan_child_bus' and 'pci_scan_bus_parented')
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Check to make sure ppc_md.init_IRQ has been set before calling it.
Signed-off-by: Sonny Rao <sonny@burdell.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds irq_create_direct_mapping(). This routine is
an alternative to irq_create_mapping(), for irq controllers that
can use linux virq numbers directly as hardware numbers.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A future patch will need the logic at the end of irq_create_mapping()
which setups a virq and installs it in the irq_map. So split it out
into a new function irq_setup_virq().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Uninline virq_to_hw and export it so modules can use it. The alternative
would be to export the irq_map array instead, but it's an infrequently
called function, and keeping the array unexported seems considerably
cleaner.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
APUS (the Amiga Power-Up System) is not supported under arch/powerpc
and it's unlikely it ever will be. Therefore, this patch removes the
fragments of APUS support code from arch/powerpc which have been
copied from arch/ppc.
A few APUS references are left in asm-powerpc in .h files which are
still used from arch/ppc.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There is a thinko in the irq code, it uses IRQ_NONE to indicate no irq,
whereas it should be using NO_IRQ. IRQ_NONE is returned from irq
handlers to say "not handled".
As it happens they currently have the same value (0), so this is just for
future proof-ness.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch renames the raw hard_irq_{enable,disable} into
__hard_irq_{enable,disable} and introduces a higher level hard_irq_disable()
function that can be used by any code to enforce that IRQs are fully disabled,
not only lazy disabled.
The difference with the __ versions is that it will update some per-processor
fields so that the kernel keeps track and properly re-enables them in the next
local_irq_disable();
This prepares powerpc for my next patch that introduces hard_irq_disable()
generically.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rip out the existing powerpc msi stubs. These were the start of an
implementation based on ppc_md calls, but were never used in mainline.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The PS3 HV will deliver soft-disabled interrupts at the next HV call or
interrupt. Add an HV call to local_irq_restore() to force the timely
delivery of any pending interrupts.
This fixes the system slowdown bug reported here
http://bugzilla.kernel.org/show_bug.cgi?id=8260
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Use DEFINE_SPINLOCK instead of initializing spinlocks to
SPIN_LOCK_UNLOCKED, since DEFINE_SPINLOCK is better for lockdep.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In some cases when we are not using msi we need a way to ensure that the
hardware does not have an msi capability enabled. Currently the code has been
calling disable_msi_mode to try and achieve that. However disable_msi_mode
has several other side effects and is only available when msi support is
compiled in so it isn't really appropriate.
Instead this patch implements pci_msi_off which disables all msi and msix
capabilities unconditionally with no additional side effects.
pci_disable_device was redundantly clearing the bus master enable flag and
clearing the msi enable bit. A device that is not allowed to perform bus
mastering operations cannot generate intx or msi interrupt messages as those
are essentially a special case of dma, and require bus mastering. So the call
in pci_disable_device to disable msi capabilities was redundant.
quirk_pcie_pxh also called disable_msi_mode and is updated to use pci_msi_off.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/irq.c contains a comment that speaks of -1 and -2 as interrupt
numbers, but this is actually dependent on configuration options now.
Replace by NO_IRQ and NO_IRQ_ENABLED.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds irq remapping hook. On interrupt mechanism on Beat,
when an irq outlet which has an id which is formerly used is created,
remapping the irq is required.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Rewrite local_get_flags and local_irq_disable to use r13 explicitly,
to avoid the risk that gcc will split get_paca()->soft_enabled into a
sequence unsafe against preemption. Similar care in local_irq_restore.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It makes for a friendlier API if irq_dispose_mapping(NO_IRQ) is a
nop, rather than triggering a WARN_ON.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This implements a lazy strategy for disabling interrupts. This means
that local_irq_disable() et al. just clear the 'interrupts are
enabled' flag in the paca. If an interrupt comes along, the interrupt
entry code notices that interrupts are supposed to be disabled, and
clears the EE bit in SRR1, clears the 'interrupts are hard-enabled'
flag in the paca, and returns. This means that interrupts only
actually get disabled in the processor when an interrupt comes along.
When interrupts are enabled by local_irq_enable() et al., the code
sets the interrupts-enabled flag in the paca, and then checks whether
interrupts got hard-disabled. If so, it also sets the EE bit in the
MSR to hard-enable the interrupts.
This has the potential to improve performance, and also makes it
easier to make a kernel that can boot on iSeries and on other 64-bit
machines, since this lazy-disable strategy is very similar to the
soft-disable strategy that iSeries already uses.
This version renames paca->proc_enabled to paca->soft_enabled, and
changes a couple of soft-disables in the kexec code to hard-disables,
which should fix the crash that Michael Ellerman saw. This doesn't
yet use a reserved CR field for the soft_enabled and hard_enabled
flags. This applies on top of Stephen Rothwell's patches to make it
possible to build a combined iSeries/other kernel.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove struct pt_regs * from all handlers.
Also remove the regs argument from get_irq() functions.
Compile tested with arch/powerpc/config/* and
arch/ppc/configs/prep_defconfig
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
There's a bug in irq_alloc_virt() if it's asked for more than 1 interrupt,
if it can't find a slot it might look past the end of the irq_map.
To be clear: the bug is that the continue affects the inner for loop,
not the outer one, so i becomes j + 1 and then we continue the inner
loop without checking if i is still <= limit.
This fixes it. No one in the kernel actually calls this with count >
1, so it's not critical.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When reworking the powerpc irq code, I figured out that we were using
the radix tree in a racy way. As a temporary fix, I put a spinlock in
there. However, this can have a significant impact on performances. This
patch reworks that to use a smarter technique based on the fact that
what we need is in fact a rwlock with extremely rare writers (thus
optimized for the read path).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The code for using the radix tree for reverse mapping of interrupts has
a typo that causes it to create incorrect mappings if the software and
hardware numbers happen to be different. This would, among others, cause
the IDE interrupt to fail on js20's. This fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch slightly reworks the new irq code to fix a small design error. I
removed the passing of the trigger to the map() calls entirely, it was not a
good idea to have one call do two different things. It also fixes a couple of
corner cases.
Mapping a linux virtual irq to a physical irq now does only that. Setting the
trigger is a different action which has a different call.
The main changes are:
- I no longer call host->ops->map() for an already mapped irq, I just return
the virtual number that was already mapped. It was called before to give an
opportunity to change the trigger, but that was causing issues as that could
happen while the interrupt was in use by a device, and because of the
trigger change, map would potentially muck around with things in a racy way.
That was causing much burden on a given's controller implementation of
map() to get it right. This is much simpler now. map() is only called on
the initial mapping of an irq, meaning that you know that this irq is _not_
being used. You can initialize the hardware if you want (though you don't
have to).
- Controllers that can handle different type of triggers (level/edge/etc...)
now implement the standard irq_chip->set_type() call as defined by the
generic code. That means that you can use the standard set_irq_type() to
configure an irq line manually if you wish or (though I don't like that
interface), pass explicit trigger flags to request_irq() as defined by the
generic kernel interfaces. Also, using those interfaces guarantees that
your controller set_type callback is called with the descriptor lock held,
thus providing locking against activity on the same interrupt (including
mask/unmask/etc...) automatically. A result is that, for example, MPIC's
own map() implementation calls irq_set_type(NONE) to configure the hardware
to the default triggers.
- To allow the above, the irq_map array entry for the new mapped interrupt
is now set before map() callback is called for the controller.
- The irq_create_of_mapping() (also used by irq_of_parse_and_map()) function
for mapping interrupts from the device-tree now also call the separate
set_irq_type(), and only does so if there is a change in the trigger type.
- While I was at it, I changed pci_read_irq_line() (which is the helper I
would expect most archs to use in their pcibios_fixup() to get the PCI
interrupt routing from the device tree) to also handle a fallback when the
DT mapping fails consisting of reading the PCI_INTERRUPT_PIN to know wether
the device has an interrupt at all, and the the PCI_INTERRUPT_LINE to get an
interrupt number from the device. That number is then mapped using the
default controller, and the trigger is set to level low. That default
behaviour works for several platforms that don't have a proper interrupt
tree like Pegasos. If it doesn't work for your platform, then either
provide a proper interrupt tree from the firmware so that fallback isn't
needed, or don't call pci_read_irq_line()
- Add back a bit that got dropped by my main rework patch for properly
clearing pending IPIs on pSeries when using a kexec
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: add defconfig for Freescale MPC8349E-mITX board
powerpc: Add base support for the Freescale MPC8349E-mITX eval board
Documentation: correct values in MPC8548E SEC example node
[POWERPC] Actually copy over i8259.c to arch/ppc/syslib this time
[POWERPC] Add new interrupt mapping core and change platforms to use it
[POWERPC] Copy i8259 code back to arch/ppc
[POWERPC] New device-tree interrupt parsing code
[POWERPC] Use the genirq framework
[PATCH] genirq: Allow fasteoi handler to retrigger disabled interrupts
[POWERPC] Update the SWIM3 (powermac) floppy driver
[POWERPC] Fix error handling in detecting legacy serial ports
[POWERPC] Fix booting on Momentum "Apache" board (a Maple derivative)
[POWERPC] Fix various offb and BootX-related issues
[POWERPC] Add a default config for 32-bit CHRP machines
[POWERPC] fix implicit declaration on cell.
[POWERPC] change get_property to return void *
At the moment, powerpc and s390 have their own versions of do_softirq which
include local_bh_disable() and __local_bh_enable() calls. They end up
calling __do_softirq (in kernel/softirq.c) which also does
local_bh_disable/enable.
Apparently the two levels of disable/enable trigger a warning from some
validation code that Ingo is working on, and he would like to see the outer
level removed. But to do that, we have to move the account_system_vtime
calls that are currently in the arch do_softirq() implementations for
powerpc and s390 into the generic __do_softirq() (this is a no-op for other
archs because account_system_vtime is defined to be an empty inline
function on all other archs). This patch does that.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Accurate hard-IRQ-flags and softirq-flags state tracing.
This allows us to attach extra functionality to IRQ flags on/off
events (such as trace-on/off).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds the new irq remapper core and removes the old one. Because
there are some fundamental conflicts with the old code, like the value
of NO_IRQ which I'm now setting to 0 (as per discussions with Linus),
etc..., this commit also changes the relevant platform and driver code
over to use the new remapper (so as not to cause difficulties later
in bisecting).
This patch removes the old pre-parsing of the open firmware interrupt
tree along with all the bogus assumptions it made to try to renumber
interrupts according to the platform. This is all to be handled by the
new code now.
For the pSeries XICS interrupt controller, a single remapper host is
created for the whole machine regardless of how many interrupt
presentation and source controllers are found, and it's set to match
any device node that isn't a 8259. That works fine on pSeries and
avoids having to deal with some of the complexities of split source
controllers vs. presentation controllers in the pSeries device trees.
The powerpc i8259 PIC driver now always requests the legacy interrupt
range. It also has the feature of being able to match any device node
(including NULL) if passed no device node as an input. That will help
porting over platforms with broken device-trees like Pegasos who don't
have a proper interrupt tree.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adapts the generic powerpc interrupt handling code, and all of
the platforms except for the embedded 6xx machines, to use the new
genirq framework.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Consolidation: remove the irq_affinity[NR_IRQS] array and move it into the
irq_desc[NR_IRQS].affinity field.
[akpm@osdl.org: sparc64 build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.
While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.
The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.
This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.
As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.
The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.
We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.
This patch:
rename desc->handler to desc->chip.
Originally i did not want to do this, because it's a big patch. But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.
I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.
So lets get over with this quickly. The conversion was done automatically
via scripts and converts all the code in the kernel.
This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.
[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The hardirq_ctx and softirq_ctx variables are written to on init only,
Signed-off-by: Andreas Mohr <andi@lisas.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Instead of trying to make PPC64 MSI fit in a Intel-centric MSI layer, a
simple short-term solution is to hook the pci_{en/dis}able_msi() calls
and make a machdep call.
The rest of the MSI functions are superfluous for what is needed at this
time. Many of which can have machdep calls added as needed.
Ben and Michael Ellerman are looking into rewrite the MSI layer to be
more generic. However, in the meantime this works as a interim
solution.
Signed-off-by: Jake Moilanen <moilanen@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The iSeries Hypervisor only allows us to specify IRQ numbers up to 255 (it
has a u8 field to pass it in). This patch allows platforms to specify a
maximum to the virtual IRQ numbers we will use and has iSeries set that
to 255. If not set, the maximum is NR_IRQS - 1 (as before).
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all. The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().
This patch is a kernel-wide sweep of all instances of NR_CPUS. I found very
few instances of this bug, if any. But the patch converts lots of open-coded
test to use the preferred helper macros.
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This implements accurate task and cpu time accounting for 64-bit
powerpc kernels. Instead of accounting a whole jiffy of time to a
task on a timer interrupt because that task happened to be running at
the time, we now account time in units of timebase ticks according to
the actual time spent by the task in user mode and kernel mode. We
also count the time spent processing hardware and software interrupts
accurately. This is conditional on CONFIG_VIRT_CPU_ACCOUNTING. If
that is not set, we do tick-based approximate accounting as before.
To get this accurate information, we read either the PURR (processor
utilization of resources register) on POWER5 machines, or the timebase
on other machines on
* each entry to the kernel from usermode
* each exit to usermode
* transitions between process context, hard irq context and soft irq
context in kernel mode
* context switches.
On POWER5 systems with shared-processor logical partitioning we also
read both the PURR and the timebase at each timer interrupt and
context switch in order to determine how much time has been taken by
the hypervisor to run other partitions ("steal" time). Unfortunately,
since we need values of the PURR on both threads at the same time to
accurately calculate the steal time, and since we can only calculate
steal time on a per-core basis, the apportioning of the steal time
between idle time (time which we ceded to the hypervisor in the idle
loop) and actual stolen time is somewhat approximate at the moment.
This is all based quite heavily on what s390 does, and it uses the
generic interfaces that were added by the s390 developers,
i.e. account_system_time(), account_user_time(), etc.
This patch doesn't add any new interfaces between the kernel and
userspace, and doesn't change the units in which time is reported to
userspace by things such as /proc/stat, /proc/<pid>/stat, getrusage(),
times(), etc. Internally the various task and cpu times are stored in
timebase units, but they are converted to USER_HZ units (1/100th of a
second) when reported to userspace. Some precision is therefore lost
but there should not be any accumulating error, since the internal
accumulation is at full precision.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch removes all self references and fixes references to files
in the now defunct arch/ppc64 tree. I think this accomplises
everything wanted, though there might be a few references I missed.
Signed-off-by: Jon Mason <jdmason@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At present the lppaca - the structure shared with the iSeries
hypervisor and phyp - is contained within the PACA, our own low-level
per-cpu structure. This doesn't have to be so, the patch below
removes it, making a separate array of lppaca structures.
This saves approximately 500*NR_CPUS bytes of image size and kernel
memory, because we don't need aligning gap between the Linux and
hypervisor portions of every PACA. On the other hand it means an
extra level of dereference in many accesses to the lppaca.
The patch also gets rid of several places where we assign the paca
address to a local variable for no particular reason.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
