Because of speculative event roll back, it is possible for some event coutners
to decrease between reads on POWER7. This causes a problem with the way that
counters are updated. Delta calues are calculated in a 64 bit value and the
top 32 bits are masked. If the register value has decreased, this leaves us
with a very large positive value added to the kernel counters. This patch
protects against this by skipping the update if the delta would be negative.
This can lead to a lack of precision in the coutner values, but from my testing
the value is typcially fewer than 10 samples at a time.
Signed-off-by: Eric B Munson <emunson@mgebm.net>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This problem was noticed on an MPC855T platform. Ftrace did oops
when trying to write to the kernel text segment.
Many thanks to Joakim for finding the root cause of this problem.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We currently enable interrupts before the dispatch log for the boot
cpu is setup. If a timer interrupt comes in early enough we oops in
scan_dispatch_log:
Unable to handle kernel paging request for data at address 0x00000010
...
.scan_dispatch_log+0xb0/0x170
.account_system_vtime+0xa0/0x220
.irq_enter+0x88/0xc0
.do_IRQ+0x48/0x230
The patch below adds a check to scan_dispatch_log to ensure the
dispatch log has been allocated.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
PAPR specifies that DTL buffers can not cross AMS environments (aka CMO
in the PAPR) and can not cross a memory entitlement granule boundary
(4k). This is found in section 14.11.3.2 H_REGISTER_VPA of the PAPR.
kmalloc does not guarantee an alignment of the allocation, though,
beyond 8 bytes (at least in my understanding). Create a special kmem
cache for DTL buffers with the alignment requirement.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Recent commit b987812b3f caused
a compile failure on UP because a considerably large block
of the file was included within CONFIG_SMP, hence making a stub
function not exposed on UP builds when it needed to be.
Relocate the stub to the #else /* ! CONFIG_SMP */ section
and also annotate the relevant else/endif so that nobody
else falls into the same trap I did.
Reported-by: Michael Guntsche <mike@it-loops.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Fix a possible problem with mport registration left non-cleared after
fsl_rio_setup() exits on link error. Abort mport initialization if
registration failed.
This patch is applicable to 2.6.39-rc1 only. The problem does not exist
for earlier versions.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We currently dont have CPU Hotplug support working on 85xx so we need to
disable Suspsend support as it will force enabling of CPU Hotplug.
arch/powerpc/kernel/built-in.o: In function `cpu_die': arch/powerpc/kernel/smp.c:702: undefined reference to `start_secondary_resume'
make: *** [.tmp_vmlinux1] Error 1
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
e500mc does not support the HID0/MSR mechanism that is used by e500_idle
(and there are also issues with waking on certain types of interrupts).
Further, even if napping is never actually enabled, just having
CPU_FTR_CAN_NAP will cause machine_init() to overwrite the board's supplied
ppc_md.power_save().
We drop CPU_FTR_MAYBE_CAN_DOZE becuase we should use 'wait' instead on
e500mc.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The CPU_FTRS_POSSIBLE and CPU_FTRS_ALWAYS defines did not encompass
e5500 CPU features when built for 64-bit. This causes issues with
cpu_has_feature() as it utilizes the POSSIBLE & ALWAYS defines as part
of its check.
Create a unique CPU_FTRS_E5500 (as its different from CPU_FTRS_E500MC),
created a new group for 64-bit Book3e based CPUs and add CPU_FTRS_E5500
to that group.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
serial port nodes with the property status="disabled" are not usable and so
avoid adding "disabled" port with the system.
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
PCIe nodes with the property status="disabled" are not usable and so
avoid adding "disabled" PCIe bridge with the system.
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose. However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation. Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.
To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it. Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Commit b3df895aeb "powerpc/kexec: Add support for FSL-BookE"
introduced the original PPC_STD_MMU_64 checks around the function
crash_kexec_wait_realmode(). Then commit c2be05481f
"powerpc: Fix default_machine_crash_shutdown #ifdef botch" changed
the ifdef around the calling site to add a check on SMP, but the
ifdef around the function itself was left unchanged, leaving an
unused function for PPC_STD_MMU_64=y and SMP=n
Rather than have two ifdefs that can get out of sync like this,
simply put the corrected conditional around the function and use
a stub to get rid of one set of ifdefs completely.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Fix some minor typos:
* informations => information
* there own => their own
* these => this
Signed-off-by: Sylvestre Ledru <sylvestre.ledru@scilab.org>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PCIe memory address space is 1:1 mapped with u-boot.
Update dts of Px020RDB i.e. P1020RDB and P2020RDB to match the address map
changes in u-boot.
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Instead of creating idle threads at boot for all possible CPUs, we
create them on demand, like x86 or ARM, and we properly call init_idle
to re-initialize an idle thread when a CPU was unplugged and is now
re-plugged.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Instead, keep it static, expose an accessor and use that from
the PowerMac code. Avoids easy namespace collisions and will
make it easier to consolidate with other implementations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On some machines that use i2c to synchronize the timebases (such
as PowerMac7,2/7,3 G5 machines), hotplug CPU would crash when
putting back a new CPU online due to the underlying i2c bus being
closed.
This uses the newly added bringup_done() callback to move the close
along with other housekeeping calls, and adds a CPU notifier to
re-open the i2c bus around subsequent hotplug operations
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This allows us to stop abusing smp_ops->setup_cpu() for cleanup
tasks that have to take place after the initial boot time CPU
bringup.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current code soft-disables, and then goes to NAP mode which
turns interrupts on. That means that if an interrupt occurs, we
will hit the masked interrupt code path which isn't what we want,
as it will return with EE off, which will either get us out of
NAP mode, or fail to enter it (according to spec).
Instead, let's just rely on the fact that it is safe to take
decrementer interrupts on an offline CPU and leave interrupts
enabled. We can also get rid of the special case in asm for
power4_cpu_offline_powersave() and just use power4_idle().
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Those instructions do nothing on non-threaded processors such
as 970's used on those machines.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use the generic code, just add the MPIC priority setting,
I don't see any use in mucking around with the decrementer,
as 32-bit will have EE off all along, and 64-bit will be able
to deal with it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use generic cpu_state, call idle_task_exit() properly, and
remove smp_core99_cpu_die() which isn't useful, the generic
function does the job just fine.
Remove the last remnants of cpu_enable(), everybody uses the normal
__cpu_up() path now
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is used by some "soft" hotplug implementations. I needs to
call idle_task_exit() when the CPU is going away, and we remove
the now no-longer needed set_cpu_online() and local_irq_enable()
which are handled by the return to start_secondary
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Various thing are torn down when a CPU is hot-unplugged. That CPU
is expected to go back to start_secondary when re-plugged to re
initialize everything, such as clock sources, maps, ...
Some implementations just return from cpu_die() callback
in the idle loop when the CPU is "re-plugged". This is not enough.
We fix it using a little asm trampoline which resets the stack
and calls back into start_secondary as if we were all fresh from
boot. The trampoline already existed on ppc64, but we add it for
ppc32
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With some implementations, it is possible that a timer interrupt
occurs every few seconds on an offline CPU. In this case, just
re-arm the decrementer and return immediately
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
avr32: Fix missing irq namespace conversion
powerpc: qe_ic: Rename get_irq_desc_data and get_irq_desc_chip
genirq: Remove the now obsolete config options and select statements
arm: versatile : Fix typo introduced in irq namespace cleanup
sound: Fixup the last user of the old irq functions
genirq: Remove obsolete comment
genirq: Remove now obsolete set_irq_wake()
sh: Fix irq cleanup fallout
x86: apb_timer: Fixup genirq fallout
genirq: Fix misnamed label in handle_edge_eoi_irq
Fix up crazy conflict in arch/powerpc/include/asm/qe_ic.h:
- commit eead4d5c63 ("powerpc: qe_ic: Rename get_irq_desc_data and
get_irq_desc_chip") made the helper functions use
irq_desc_get_handler_data() instead of the legacy (and no longer
existing) get_irq_desc_data.
- commit d4db35e8dc ("powerpc/qe_ic: Fix another breakage from the
irq_data conversion") used irq_desc_get_chip_data() instead.
According to Thomas, the former is the correct direct conversion, but it
does look like both should work (arch/powerpc/sysdev/qe_lib/qe_ic.c
seems to initialize both to the same thing), and the chip data in some
ways is the more logical. Somebody should really decide on one of the
other.
This merge picks irq_desc_get_handler_data() as the straightforward pure
conversion to new names, as per Thomas.
These two functions disappeared in commit
0c6f8a8b91
"genirq: Remove compat code"
but they still exist in qe_ic.h.
This patch renames the function to their new names.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Lennert Buytenhek <buytenh@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
LKML-Reference: <20110330132504.GA31832@riccoc20.at.omicron.at>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Ensure the Chelsio T3/T4 network drivers and iWARP drivers are
enabled in the pseries config.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Recent upstream builds with allmodconfig fail due to lack of space
between 0x3000 and 0x6000. We have a hard block at 0x7000 but we can
spare a page by moving the STAB0 from 0x6000 to 0x8000.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
commit cf9efce0ce (powerpc: Account time using timebase rather
than PURR) used in_irq() to detect if the time was spent in
interrupt processing. This only catches hardirq context so if we
are in softirq context and in the idle loop we end up accounting it
as idle time. If we instead use in_interrupt() we catch both softirq
and hardirq time.
The issue was found when running a network intensive workload. top
showed the following:
0.0%us, 1.1%sy, 0.0%ni, 85.7%id, 0.0%wa, 9.9%hi, 3.3%si, 0.0%st
85.7% idle. But this was wildly different to the perf events data.
To confirm the suspicion I ran something to keep the core busy:
# yes > /dev/null &
8.2%us, 0.0%sy, 0.0%ni, 0.0%id, 0.0%wa, 10.3%hi, 81.4%si, 0.0%st
We only got 8.2% of the CPU for the userspace task and softirq has
shot up to 81.4%.
With the patch below top shows the correct stats:
0.0%us, 0.0%sy, 0.0%ni, 5.3%id, 0.0%wa, 13.3%hi, 81.3%si, 0.0%st
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If a given firmware doesn't have a token to support query-cpu-stopped-state,
its not likely to change during the lifetime of the kernel.
Only print this information once, not once per secondary thread.
While here, make the line wrap grep friendly.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
