The mktree utility defines some variables as "uint", although this is not a
standard C type, and so cross-compiling on Mac OS X fails. Change this to
"unsigned int".
Signed-off-by: Timur Tabi <timur@freescale.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The interrupt controller was not handling level interrupts correctly
such that duplicate interrupts were happening. This fixes the problem
and adds edge type interrupts which are needed in Xilinx hardware.
Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
It is common to use U-Boot on Xilinx Virtex platforms. This patch
ensures that CONFIG_DEFAULT_UIMAGE is selected for virtex
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Fix this build error when CONFIG_BLOCK is not set:
drivers/cdrom/viocd.c: In function 'viocd_blk_open':
drivers/cdrom/viocd.c:156: error: dereferencing pointer to incomplete type
drivers/cdrom/viocd.c: In function 'viocd_blk_release':
drivers/cdrom/viocd.c:162: error: dereferencing pointer to incomplete type
drivers/cdrom/viocd.c: In function 'viocd_blk_ioctl':
drivers/cdrom/viocd.c:170: error: dereferencing pointer to incomplete type
drivers/cdrom/viocd.c: In function 'viocd_blk_media_changed':
drivers/cdrom/viocd.c:176: error: dereferencing pointer to incomplete type
...
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Merge reason: both topics modify the APIC code but were able to do it in
parallel so far. An upcoming patch generates a conflict so
merge them to avoid the conflict.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
commit b31a1d8b41 ("gianfar: Convert
gianfar to an of_platform_driver"), possibly due merge issues,
reintroduced completely unneded mpc83xx_wdt_init call, which
I removed some time ago in commit 20d38e01d4
("powerpc/fsl_soc: remove mpc83xx_wdt code").
Remove it once again.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This build failure:
arch/powerpc/sysdev/mpic.c:810: error: conflicting types for 'mpic_set_affinity'
arch/powerpc/sysdev/mpic.h:39: error: previous declaration of 'mpic_set_affinity' was here
make[2]: *** [arch/powerpc/sysdev/mpic.o] Error 1
make[2]: *** Waiting for unfinished jobs....
Triggers because the function prototype was not updated when the
function call signature got changed by:
d5dedd4: irq: change ->set_affinity() to return status
[ Impact: build fix on powerpc ]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-arch@vger.kernel.org
LKML-Reference: <49F654E9.4070809@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Fix setting of oprofile cpu type
powerpc: Update MPC5xxx and Xilinx Virtex maintainer entries
powerpc adjust oprofile_cpu_type version 3
The powerpc kernel always requires an Open Firmware like device tree
to supply device information. On systems without OF, this comes from
a flattened device tree blob. This blob is usually generated by dtc,
a tool which compiles a text description of the device tree into the
flattened format used by the kernel. Sometimes, the bootwrapper makes
small changes to the pre-compiled device tree blob (e.g. filling in
the size of RAM). To do this it uses the libfdt library.
Because these are only used on powerpc, the code for both these tools
is included under arch/powerpc/boot (these were imported and are
periodically updated from the upstream dtc tree).
However, the microblaze architecture, currently being prepared for
merging to mainline also uses dtc to produce device tree blobs. A few
other archs have also mentioned some interest in using dtc.
Therefore, this patch moves dtc and libfdt from arch/powerpc into
scripts, where it can be used by any architecture.
The vast bulk of this patch is a literal move, the rest is adjusting
the various Makefiles to use dtc and libfdt correctly from their new
locations.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some drivers using of_register_platform_driver() wrapper break on sparc
because the wrapper isn't in the header file. This patch moves it from
Microblaze and PowerPC implementations and makes it common code.
Fixes this sparc64 allmodconfig build error (at least):
drivers/leds/leds-gpio.c: In function `gpio_led_init':
drivers/leds/leds-gpio.c:295: error: implicit declaration of function `of_register_platform_driver'
drivers/leds/leds-gpio.c: In function `gpio_led_exit':
drivers/leds/leds-gpio.c:311: error: implicit declaration of function `of_unregister_platform_driver'
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit 2657dd4e30 introduced a
bug where we would now always override the "real" oprofile CPU
type with the "compatible" one provided by a pseudo-PVR in the
device-tree which is incorrect and breaks oprofile on all current
configs since the "compatible" ones aren't yet recognized.
This fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Oprofile is changing the naming it is using for the compatibility modes.
Instead of having compat-power<x>, oprofile will go to family naming
convention and use ibm-compat-v<x>. Currently only ibm-compat-v1 will
be defined.
The notion of compatibility events just started with POWER6. So there is
no way that any other tool could exist that is using these
oprofile_cpu_type strings we want to change.
Signed-off-by: Mike Wolf <mjw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
POWER5+ and POWER6 have two hardware counters with limited functionality:
PMC5 counts instructions completed in run state and PMC6 counts cycles
in run state. (Run state is the state when a hardware RUN bit is 1;
the idle task clears RUN while waiting for work to do and sets it when
there is work to do.)
These counters can't be written to by the kernel, can't generate
interrupts, and don't obey the freeze conditions. That means we can
only use them for per-task counters (where we know we'll always be in
run state; we can't put a per-task counter on an idle task), and only
if we don't want interrupts and we do want to count in all processor
modes.
Obviously some counters can't go on a limited hardware counter, but there
are also situations where we can only put a counter on a limited hardware
counter - if there are already counters on that exclude some processor
modes and we want to put on a per-task cycle or instruction counter that
doesn't exclude any processor mode, it could go on if it can use a
limited hardware counter.
To keep track of these constraints, this adds a flags argument to the
processor-specific get_alternatives() functions, with three bits defined:
one to say that we can accept alternative event codes that go on limited
counters, one to say we only want alternatives on limited counters, and
one to say that this is a per-task counter and therefore events that are
gated by run state are equivalent to those that aren't (e.g. a "cycles"
event is equivalent to a "cycles in run state" event). These flags
are computed for each counter and stored in the counter->hw.counter_base
field (slightly wonky name for what it does, but it was an existing
unused field).
Since the limited counters don't freeze when we freeze the other counters,
we need some special handling to avoid getting skew between things counted
on the limited counters and those counted on normal counters. To minimize
this skew, if we are using any limited counters, we read PMC5 and PMC6
immediately after setting and clearing the freeze bit. This is done in
a single asm in the new write_mmcr0() function.
The code here is specific to PMC5 and PMC6 being the limited hardware
counters. Being more general (e.g. having a bitmap of limited hardware
counter numbers) would have meant more complex code to read the limited
counters when freezing and unfreezing the normal counters, with
conditional branches, which would have increased the skew. Since it
isn't necessary for the code to be more general at this stage, it isn't.
This also extends the back-ends for POWER5+ and POWER6 to be able to
handle up to 6 counters rather than the 4 they previously handled.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <18936.19035.163066.892208@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch renames struct hw_perf_counter_ops into struct pmu. It
introduces a structure to describe a cpu specific pmu (performance
monitoring unit). It may contain ops and data. The new name of the
structure fits better, is shorter, and thus better to handle. Where it
was appropriate, names of function and variable have been changed too.
[ Impact: cleanup ]
Signed-off-by: Robert Richter <robert.richter@amd.com>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1241002046-8832-7-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc/ps3: Fix build error on UP
powerpc/cell: Select PCI for IBM_CELL_BLADE AND CELLEB
powerpc: ppc32 needs elf_read_implies_exec()
powerpc/86xx: Add device_type entry to soc for ppc9a
powerpc/44x: Correct memory size calculation for denali-based boards
maintainers: Fix PowerPC 4xx git tree
powerpc: fix for long standing bug noticed by gcc 4.4.0
Revert "powerpc: Add support for early tlbilx opcode"
Commit edada399 broke the build on 64-bit powerpc because it moved the
__ftr_alt_* sections of a file away from the .text section, causing
link failures due to relative conditional branch targets being too far
away from the branch instructions. This happens on pretty much all
64-bit powerpc configs.
This change reverts commit edada399 while preserving the update from
the *.refok sections to .ref.text that has happened since.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Requested-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
according to Ingo, change set_affinity() in irq_chip should return int,
because that way we can handle failure cases in a much cleaner way, in
the genirq layer.
v2: fix two typos
[ Impact: extend API ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-arch@vger.kernel.org
LKML-Reference: <49F654E9.4070809@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
A non-SMP version of smp_send_stop() is now included in smp.h.
Remove the unneeded definition in the PS3 smp.c.
Fixes build errors like these when CONFIG_SMP=n:
arch/powerpc/platforms/ps3/setup.c:49: error: redefinition of 'smp_send_stop'
include/linux/smp.h:125: error: previous definition of 'smp_send_stop' was here
Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently PPC_CELL_NATIVE selects PPC_OF_PLATFORM_PCI, but does not
select PCI. This can lead to a config with the former and the latter
disabled, which does not build.
To fix this PPC_CELL_NATIVE should select PCI. However, that would
force PCI on for QPACE, which also selects PPC_CELL_NATIVE. So
instead move the select of PPC_OF_PLATFORM_PCI and PCI under both
IBM_CELL_BLADE and CELLEB.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On ppc64 we implemented elf_read_implies_exec() for 32-bit binaries
because old toolchains had bugs where they didn't mark program
segments executable that needed to be. For some reason we didn't do
this on ppc32 builds. This hadn't been an issue until commit 8d30c14c
("powerpc/mm: Rework I$/D$ coherency (v3)"), which had as a side
effect that we are now enforcing execute permissions to some extent on
32-bit 4xx and Book E processors.
This fixes it by defining elf_read_implies_exec on 32-bit to turn on
the read-implies-exec behaviour on programs that are sufficiently old
that they don't have a PT_GNU_STACK program header.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The section .text.init.refok is deprecated and __REF (.ref.text)
should be used in assembly files instead. This patch cleans up a few
uses of .text.init.refok in the powerpc architecture.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rather than adding .ref.text to the powerpc linker script so that we
can use __REF on the powerpc architecture, it seems simpler to switch
to using the generic TEXT_TEXT macro.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The 'device_type = "soc";' line *is* needed in the DTS for get_immrbase()
to return the correct address.
Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text". Since this commit changes all
users in the architecture, this change should be harmless.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: Fix modular build of ide-pmac when mediabay is built in
powerpc/pasemi: Fix build error on UP
powerpc: Make macintosh/mediabay driver depend on CONFIG_BLOCK
maintainers: Fix PS3 patterns
powerpc/ps3: Fix CONFIG_PS3_FLASH=n build warning
powerpc/32: Don't clobber personality flags on exec
powerpc: Fix crash on CPU hotplug
powerpc/85xx: Remove defconfigs that mpc85xx_{smp_}defconfig cover
powerpc/85xx: Added SMP defconfig
powerpc/85xx: Enabled a bunch of FSL specific drivers/options
powerpc/85xx: Updated generic mpc85xx_defconfig
powerpc: don't disable SATA interrupts on Freescale MPC8610 HPCD
fsl_rio: Pass the proper device to dma mapping routines
powerpc: Fix of_node_put() exit path in of_irq_map_one()
powerpc/5200: defconfig updates
powerpc/5200: Add FLASH nodes to lite5200 device tree
powerpc/device-tree: Document MTD nodes with multiple "reg" tuples
powerpc/of-device-tree: Factor MTD physmap bindings out of booting-without-of
powerpc/5200: Bring the legacy fsl_spi_platform_data hooks back
Some U-Boot versions incorrectly set the number of chipselects to two
for Sequoia/Rainier boards while they only have one chipselect hardwired.
This patch adds a workaround for this, hardcoding the number of chipselects
to one for sequioa/rainer board models and reading the actual value from
the memory controller register DDR0_10 otherwise.
It also fixes another error in the way ibm4xx_denali_fixup_memsize
calculates memory size. When testing the DDR_REDUC bit, the polarity is
backwards. A "1" implies 32-bit wide memory while a "0" implies 64-bit
wide memory.
Signed-off-by: Mikhail Zolotaryov <lebon@lebon.org.ua>
Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Signed-off-by: Steven A. Falco <sfalco@harris.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Previous gcc versions didn't notice this because one of the preceding
#ifs always evaluated to true.
gcc 4.4.0 produced this error:
arch/powerpc/mm/tlb_nohash_low.S:206:6: error: #elif with no expression
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This reverts commit e996557740. Our HW
guys were able to fix this so it never sees the light of day.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
A non-SMP version of smp_send_stop() is now included in smp.h.
Remove the unneeded definition in the pasemi setup.c.
Fixes build errors like these when CONFIG_SMP=n:
arch/powerpc/platforms/pasemi/setup.c:48: error: redefinition of ‘smp_send_stop’
include/linux/smp.h:125: error: previous definition of 'smp_send_stop' was here
Reported-by: subrata@linux.vnet.ibm.com
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fix build warnings like these when CONFIG_PS3_FLASH=n:
arch/powerpc/platforms/ps3/os-area.c: warning: 'update_flash_db' defined but not used
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that ppc32 implements address randomization it also wants to inherit
personality flags like ADDR_NO_RANDOMIZE across exec, for things like
`setarch ppc -R' to work. But the ppc32 version of SET_PERSONALITY
forcefully sets PER_LINUX, clearing all personality flags. So be
careful about preserving the flags.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
early_init_mmu_secondary() is called at CPU hotplug time, so it
must be marked as __cpuinit, not __init.
Caused by 757c74d2 ("powerpc/mm: Introduce early_init_mmu() on 64-bit").
Tested-by: Sachin Sant <sachinp@in.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Since the vast majority of 85xx platforms are UP we introduce a new SMP
config for the few platforms that have more than one core. Beyond
CONFIG_SMP=y and its dependencies this should be identical to
mpc85xx_defconfig.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Pass clocksource pointer to the read() callback for clocksources. This
allows us to share the callback between multiple instances.
[hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ULI 1575 PCI quirk function for the Freescale MPC8610 HPCD was disabling
the SATA INTx interrupt, even when SATA support was enabled. This was safe,
because the SATA driver re-enabled it. But with commit a5bfc471 ("ahci: drop
intx manipulation on msi enable"), the driver no longer does this, and so SATA
support on the 8610 HPCD is broken.
The original quirk function disabled INTx because it caused some other
interrupt problem during early development on this board, but no one remembers
any more what that problem was, and it doesn't seem to occur any more.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The driver should pass a device that specifies internal DMA ops, but
currently NULL pointer is passed, therefore following bug appears
during boot up:
------------[ cut here ]------------
Kernel BUG at c0018a7c [verbose debug info unavailable]
Oops: Exception in kernel mode, sig: 5 [#1]
[...]
NIP [c0018a7c] fsl_rio_doorbell_init+0x34/0x60
LR [c0018a70] fsl_rio_doorbell_init+0x28/0x60
Call Trace:
[ef82bda0] [c0018a70] fsl_rio_doorbell_init+0x28/0x60 (unreliable)
[ef82bdc0] [c0019160] fsl_rio_setup+0x6b8/0x84c
[ef82be20] [c02d28ac] fsl_of_rio_rpn_probe+0x30/0x50
[ef82be40] [c0234f20] of_platform_device_probe+0x5c/0x84
[...]
---[ end trace 561bb236c800851f ]---
This patch fixes the issue.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: pseries/dtl.c should include asm/firmware.h
powerpc: Fix data-corrupting bug in __futex_atomic_op
powerpc/pseries: Set error_state to pci_channel_io_normal in eeh_report_reset()
powerpc: Allow 256kB pages with SHMEM
powerpc: Document new FSL I2C bindings and cleanup
powerpc/mm: Fix compile warning
powerpc/85xx: TQM8548: update defconfig
powerpc/85xx: TQM8548: use proper phy-handles for enet2 and enet3
powerpc/85xx: TQM85xx: correct address of LM75 I2C device nodes
powerpc: Add support for early tlbilx opcode
powerpc: Fix tlbilx opcode
A randconfig build on powerpc failed with:
dtl.c: In function 'dtl_init':
dtl.c:238: error: implicit declaration of function 'firmware_has_feature'
dtl.c:238: error: 'FW_FEATURE_SPLPAR' undeclared (first use in this function)
- We need firmware.h for these definitions.
Signed-off-by: Sachin Sant <sachinp@in.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Richard Henderson pointed out that the powerpc __futex_atomic_op has a
bug: it will write the wrong value if the stwcx. fails and it has to
retry the lwarx/stwcx. loop, since 'oparg' will have been overwritten
by the result from the first time around the loop. This happens
because it uses the same register for 'oparg' (an input) as it uses
for the result.
This fixes it by using separate registers for 'oparg' and 'ret'.
Cc: stable@kernel.org
Signed-off-by: Paul Mackerras <paulus@samba.org>
While adding native EEH support to Emulex and Qlogic drivers, it was
discovered that dev->error_state was set to pci_io_channel_normal too
late in the recovery process. These drivers rely on error_state to
determine if they can access the device in their slot_reset callback,
thus error_state needs to be set to pci_io_channel_normal in
eeh_report_reset(). Below is a detailed explanation (courtesy of Richard
Lary) as to why this is necessary.
Background:
PCI MMIO or DMA accesses to a frozen slot generate additional EEH
errors. If the number of additional EEH errors exceeds EEH_MAX_FAILS the
adapter will be shutdown. To avoid triggering excessive EEH errors and
an undesirable adapter shutdown, some drivers use the
pci_channel_offline(dev) wrapper function to return a Boolean value
based on the value of pci_dev->error_state to determine if PCI MMIO or
DMA accesses are safe. If the wrapper returns TRUE, drivers must not
make PCI MMIO or DMA access to their hardware.
The pci_dev structure member error_state reflects one of three values,
1) pci_channel_io_normal, 2) pci_channel_io_frozen, 3)
pci_channel_io_perm_failure. Function pci_channel_offline(dev) returns
TRUE if error_state is pci_channel_io_frozen or pci_channel_io_perm_failure.
The EEH driver sets pci_dev->error_state to pci_channel_io_frozen at the
point where the PCI slot is frozen. Currently, the EEH driver restores
dev->error_state to pci_channel_io_normal in eeh_report_resume() before
calling the driver's resume callback. However, when the EEH driver calls
the driver's slot_reset callback() from eeh_report_reset(), it
incorrectly indicates the error state is still pci_channel_io_frozen.
Waiting until eeh_report_resume() to restore dev->error_state to
pci_channel_io_normal is too late for Emulex and QLogic FC drivers and
any other drivers which are designed to use common code paths in these
two cases: i) those called after the driver's slot_reset callback() and
ii) those called after the PCI slot is frozen but before the driver's
slot_reset callback is called. Case i) all driver paths executed to
reinitialize the hardware after a reset and case ii) all code paths
executed by driver kernel threads that run asynchronous to the main
driver thread, such as interrupt handlers and worker threads to process
driver work queues.
Emulex and QLogic FC drivers are designed with common code paths which
require that pci_channel_offline(dev) reflect the true state of the
hardware. The state transitions that the hardware takes from Normal
Operations to Slot Frozen to Reset to Normal Operations are documented
in the Power Architecture™ Platform Requirements+ (PAPR+) in Table 75.
PE State Control.
PAPR defines the following 3 states:
0 -- Not reset, Not EEH stopped, MMIO load/store allowed, DMA allowed
(Normal Operations)
1 -- Reset, Not EEH stopped, MMIO load/store disabled, DMA disabled
2 -- Not reset, EEH stopped, MMIO load/store disabled, DMA disabled
(Slot Frozen)
An EEH error places the slot in state 2 (Frozen) and the adapter driver
is notified that an EEH error was detected. If the adapter driver
returns PCI_ERS_RESULT_NEED_RESET, the EEH driver calls
eeh_reset_device() to place the slot into state 1 (Reset) and
eeh_reset_device completes by placing the slot into State 0 (Normal
Operations). Upon return from eeh_reset_device(), the EEH driver calls
eeh_report_reset, which then calls the adapter's slot_reset callback. At
the time the adapter's slot_reset callback is called, the true state of
the hardware is Normal Operations and should be accurately reflected by
setting dev->error_state to pci_channel_io_normal.
The current implementation of EEH driver does not do so and requires
this change to correct this deficiency.
Signed-off-by: Mike Mason <mmlnx@us.ibm.com>
Acked-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that shmem's divisions by zero and SHMEM_MAX_BYTES are fixed,
let powerpc 256kB pages coexist with CONFIG_SHMEM again.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In commit 51dcdfec6a ("parport: Use the
PCI IRQ if offered") parport_pc_probe_port() gained an irqflags arg.
This isn't being supplied on powerpc. This patch make powerpc fallback
to the old behaviour, that is using "0" for irqflags.
Fixes build failure:
In file included from drivers/parport/parport_pc.c:68:
arch/powerpc/include/asm/parport.h: In function 'parport_pc_find_nonpci_ports':
arch/powerpc/include/asm/parport.h:32: error: too few arguments to function 'parport_pc_probe_port'
arch/powerpc/include/asm/parport.h:32: error: too few arguments to function 'parport_pc_probe_port'
arch/powerpc/include/asm/parport.h:32: error: too few arguments to function 'parport_pc_probe_port'
make[3]: *** [drivers/parport/parport_pc.o] Error 1
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: fix potential deadlocks on powerpc
Now that the core is using in_nmi() (added in e30e08f6, "perf_counter:
fix NMI race in task clock"), we need the powerpc perf_counter_interrupt
to call nmi_enter() and nmi_exit() in those cases where the interrupt
happens when interrupts are soft-disabled.
If interrupts were soft-enabled, we can treat it as a regular interrupt
and do irq_enter/irq_exit around the whole routine. This lets us get rid
of the test_perf_counter_pending() call at the end of
perf_counter_interrupt, thus simplifying things a little.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18909.31952.873098.336615@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul suggested we allow for data addresses to be recorded along with
the traditional IPs as power can provide these.
For now, only the software pagefault events provide data addresses,
but in the future power might as well for some events.
x86 doesn't seem capable of providing this atm.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <20090408130409.394816925@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: enable access to hardware feature
POWER processors have the ability to "mark" a subset of the instructions
and provide more detailed information on what happens to the marked
instructions as they flow through the pipeline. This marking is
enabled by the "sample enable" bit in MMCRA, and there are
synchronization requirements around setting and clearing the bit.
This adds logic to the processor-specific back-ends so that they know
which events relate to marked instructions and set the sampling enable
bit if any event that we want to put on the PMU is a marked instruction
event. It also adds logic to the generic powerpc code to do the
necessary synchronization if that bit is set.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18908.31930.1024.228867@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 4af4998b ("perf_counter: rework context time") changed struct
perf_counter_context to have a 'time' field instead of a 'time_now'
field, but neglected to fix the place in the powerpc perf_counter.c
where the time_now field was accessed. This fixes it.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18908.31922.411398.147810@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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>
arch/powerpc/mm/tlb_nohash.c: In function 'flush_tlb_mm':
arch/powerpc/mm/tlb_nohash.c:128: warning: unused variable 'cpu_mask'
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* 'i2c-for-2630-v2' of git://aeryn.fluff.org.uk/bjdooks/linux:
i2c: imx: Make disable_delay a per-device variable
i2c: xtensa s6000 i2c driver
powerpc/85xx: i2c-mpc: use new I2C bindings for the Socates board
i2c: i2c-mpc: make I2C bus speed configurable
i2c: i2c-mpc: use dev based printout function
i2c: i2c-mpc: various coding style fixes
i2c: imx: Add missing request_mem_region in probe()
i2c: i2c-s3c2410: Initialise Samsung I2C controller early
i2c-s3c2410: Simplify bus frequency calculation
i2c-s3c2410: sda_delay should be in ns, not clock ticks
i2c: iMX/MXC support
Replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32)
Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace all DMA_64BIT_MASK macro with DMA_BIT_MASK(64)
Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (28 commits)
powerpc: Fix oops when loading modules
powerpc: Wire up preadv and pwritev
powerpc/ftrace: Fix printf format warning
powerpc/ftrace: Fix #if that should be #ifdef
powerpc: Fix ptrace compat wrapper for FPU register access
powerpc: Print information about mapping hw irqs to virtual irqs
powerpc: Correct dependency of KEXEC
powerpc: Disable VSX or current process in giveup_fpu/altivec
powerpc/pseries: Enable relay in pseries_defconfig
powerpc/pseries: Fix ibm,client-architecture comment
powerpc/pseries: Scan for all events in rtasd
powerpc/pseries: Add dispatch dispersion statistics
powerpc: Clean up some prom printouts
powerpc: Print progress of ibm,client-architecture method
powerpc: Remove duplicated #include's
powerpc/pmac: Fix internal modem IRQ on Wallstreet PowerBook
powerpc/wdrtas: Update wdrtas_get_interval to use rtas_data_buf
fsl-diu-fb: Pass the proper device for dma mapping routines
powerpc/pq2fads: Update device tree for use with device-tree-aware u-boot.
cpm_uart: Disable CPM udbg when re-initing CPM uart, even if not the console.
...
Preserve I2C clock settings for the Socrates MPC8544 board.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Prepare for more generic overflow handling. The new perf_counter_overflow()
method will handle the generic bits of the counter overflow, and can return
a !0 return value, in which case the counter should be (soft) disabled, so
that it won't count until it's properly disabled.
XXX: do powerpc and swcounter
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <20090406094517.812109629@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Enable highmem support for the TQM8548-AG modules and NAND support for
the TQM8548-BE modules. Furthermore disable USB, Wireless and IDE support
because it's not available on the STK85xx starter kit.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
For enet2 and enet3 the wrong phy-handles have been used in DTS files
of the TQM8548 modules.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Commit 0f73a449a6 added I2C device nodes
for the LM75 thermal sensor on the TQM85xx modules, unfortunately with
the wrong I2C address. The LM75s are located at address 0x48.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
During the ISA 2.06 development the opcode for tlbilx changed and some
early implementations used to old opcode. Add support for a MMU_FTR
fixup to deal with this.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The tlbilx opcode was not matching the Power ISA 2.06 arch spec.
The old opcode was an early suggested opcode that changed during the
2.06 architecture process.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This fixes a problem reported by Sean MacLennan where loading any
module would cause an oops. We weren't marking the pages containing
the module text as having hardware execute permission, due to a bug
introduced in commit 8d1cf34e ("powerpc/mm: Tweak PTE bit combination
definitions"), hence trying to execute the module text caused an
exception on processors that support hardware execute permission.
This adds _PAGE_HWEXEC to the definitions of PAGE_KERNEL_X and
PAGE_KERNEL_ROX to fix this problem.
Reported-by: Sean MacLennan <smaclennan@pikatech.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
[paulus@samba.org: changed to use syscall numbers 320 and 321 since
perf_counters is currently using 319.]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
'tramp' is an unsigned long, so print it with %lx.
Fixes the following build warning:
arch/powerpc/kernel/ftrace.c:291: error: format ‘%x’ expects type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit bb7253403f ("powerpc64,
ftrace: save toc only on modules for function graph"), added an
#if CONFIG_PPC64. This changes it to #ifdef.
Fixes the following warning on 32-bit builds:
arch/powerpc/kernel/ftrace.c:562:5: error: "CONFIG_PPC64" is not defined
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The ptrace compat wrapper mishandles access to the fpu registers. The
PTRACE_PEEKUSR and PTRACE_POKEUSR requests miscalculate the index into
the fpr array due to the broken FPINDEX macro. The
PPC_PTRACE_PEEKUSR_3264 request needs to use the same formula that the
native ptrace interface uses when operating on the register number (as
opposed to the 4-byte offset). The PPC_PTRACE_POKEUSR_3264 request
didn't take TS_FPRWIDTH into account.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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>
commit 28794d34ec ("powerpc/kconfig: Kill
PPC_MULTIPLATFORM") broke KEXEC, by making it dependent on BOOK3S, while it
should be PPC_BOOK3S.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When we call giveup_fpu, we need to need to turn off VSX for the
current process. If we don't, on return to userspace it may execute a
VSX instruction before the next FP instruction, and not have its
register state refreshed correctly from the thread_struct. Ditto for
altivec.
This caused a bug where an unaligned lfs or stfs results in
fix_alignment calling giveup_fpu so it can use the FPRs (in order to
do a single <-> double conversion), and then returning to userspace
with FP off but VSX on. Then if a VSX instruction is executed, before
another FP instruction, it will proceed without another exception and
hence have the incorrect register state for VSX registers 0-31.
lfs unaligned <- alignment exception turns FP off but leaves VSX on
VSX instruction <- no exception since VSX on, hence we get the
wrong VSX register values for VSX registers 0-31,
which overlap the FPRs.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Enable relay in pseries config, ppc64_defconfig had it enabled but pseries
did not.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Instead of checking for known events, pass in all 1s so we handle future
event types. We were currently missing the IO event type.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
PHYP tells us how often a shared processor dispatch changed physical cpus.
This can highlight performance problems caused by the hypervisor.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make all messages consistent, some have spaces before the "...", some do not.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The ibm,client-architecture method will often cause a reconfiguration reboot.
When this happens the last thing we see is:
Hypertas detected, assuming LPAR !
Which doesn't explain what just happened. Wrap the ibm,client-architecture
so it's clear what is going on:
Calling ibm,client-architecture... done
In order to maintain the law of conservation of screen real estate, downgrade
two other messages to debug.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* git://git.infradead.org/mtd-2.6: (53 commits)
[MTD] struct device - replace bus_id with dev_name(), dev_set_name()
[MTD] [NOR] Fixup for Numonyx M29W128 chips
[MTD] mtdpart: Make ecc_stats more realistic.
powerpc/85xx: TQM8548: Update DTS file for multi-chip support
powerpc: NAND: FSL UPM: document new bindings
[MTD] [NAND] FSL-UPM: Add wait flags to support board/chip specific delays
[MTD] [NAND] FSL-UPM: add multi chip support
[MTD] [NOR] Add device parent info to physmap_of
[MTD] [NAND] Add support for NAND on the Socrates board
[MTD] [NAND] Add support for 4KiB pages.
[MTD] sysfs support should not depend on CONFIG_PROC_FS
[MTD] [NAND] Add parent info for CAFÉ controller
[MTD] support driver model updates
[MTD] driver model updates (part 2)
[MTD] driver model updates
[MTD] [NAND] move gen_nand's probe function to .devinit.text
[MTD] [MAPS] move sa1100 flash's probe function to .devinit.text
[MTD] fix use after free in register_mtd_blktrans
[MTD] [MAPS] Drop now unused sharpsl-flash map
[MTD] ofpart: Check name property to determine partition nodes.
...
Manually fix trivial conflict in drivers/mtd/maps/Makefile
This patch adds multi-chip support for the Micron MT29F8G08FAB NAND
flash memory on the TQM8548 modules.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patch adds support for multi-chip NAND devices to the FSL-UPM
driver. This requires support for multiple GPIOs for the RNB pins.
The NAND chips are selected through address lines defined by the
FDT property "fsl,upm-addr-line-cs-offsets".
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Add aliases, and correct CS0 offset to match how u-boot
programs it (this was not a problem with cuImage because
the wrapper would reprogram the localbus to match the device
tree).
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
CoreInt provides a mechansim to deliver the IRQ vector directly
into the core on an interrupt (via the SPR EPR) rather than having
to go IACK on the PIC. This is suppose to provide an improvment
in interrupt latency by reducing the time to get the IRQ vector.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Impact: better error reporting
At present, if hw_perf_counter_init encounters an error, all it can do
is return NULL, which causes sys_perf_counter_open to return an EINVAL
error to userspace. This isn't very informative for userspace; it means
that userspace can't tell the difference between "sorry, oprofile is
already using the PMU" and "we don't support this CPU" and "this CPU
doesn't support the requested generic hardware event".
This commit uses the PTR_ERR/ERR_PTR/IS_ERR set of macros to let
hw_perf_counter_init return an error code on error rather than just NULL
if it wishes. If it does so, that error code will be returned from
sys_perf_counter_open to userspace. If it returns NULL, an EINVAL
error will be returned to userspace, as before.
This also adapts the powerpc hw_perf_counter_init to make use of this
to return ENXIO, EINVAL, EBUSY, or EOPNOTSUPP as appropriate. It would
be good to add extra error numbers in future to allow userspace to
distinguish the various errors that are currently reported as EINVAL,
i.e. irq_period < 0, too many events in a group, conflict between
exclude_* settings in a group, and PMU resource conflict in a group.
[ v2: fix a bug pointed out by Corey Ashford where error returns from
hw_perf_counter_init were not handled correctly in the case of
raw hardware events.]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Orig-LKML-Reference: <20090330171023.682428180@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cooperate with oprofile
At present, on PowerPC, if you have perf_counters compiled in, oprofile
doesn't work. There is code to allow the PMU to be shared between
competing subsystems, such as perf_counters and oprofile, but currently
the perf_counter subsystem reserves the PMU for itself at boot time,
and never releases it.
This makes perf_counter play nicely with oprofile. Now we keep a count
of how many perf_counter instances are counting hardware events, and
reserve the PMU when that count becomes non-zero, and release the PMU
when that count becomes zero. This means that it is possible to have
perf_counters compiled in and still use oprofile, as long as there are
no hardware perf_counters active. This also means that if oprofile is
active, sys_perf_counter_open will fail if the hw_event specifies a
hardware event.
To avoid races with other tasks creating and destroying perf_counters,
we use a mutex. We use atomic_inc_not_zero and atomic_add_unless to
avoid having to take the mutex unless there is a possibility of the
count going between 0 and 1.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Orig-LKML-Reference: <20090330171023.627912475@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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: new functionality
Currently, if there are more counters enabled than can fit on the CPU,
the kernel will multiplex the counters on to the hardware using
round-robin scheduling. That isn't too bad for sampling counters, but
for counting counters it means that the value read from a counter
represents some unknown fraction of the true count of events that
occurred while the counter was enabled.
This remedies the situation by keeping track of how long each counter
is enabled for, and how long it is actually on the cpu and counting
events. These times are recorded in nanoseconds using the task clock
for per-task counters and the cpu clock for per-cpu counters.
These values can be supplied to userspace on a read from the counter.
Userspace requests that they be supplied after the counter value by
setting the PERF_FORMAT_TOTAL_TIME_ENABLED and/or
PERF_FORMAT_TOTAL_TIME_RUNNING bits in the hw_event.read_format field
when creating the counter. (There is no way to change the read format
after the counter is created, though it would be possible to add some
way to do that.)
Using this information it is possible for userspace to scale the count
it reads from the counter to get an estimate of the true count:
true_count_estimate = count * total_time_enabled / total_time_running
This also lets userspace detect the situation where the counter never
got to go on the cpu: total_time_running == 0.
This functionality has been requested by the PAPI developers, and will
be generally needed for interpreting the count values from counting
counters correctly.
In the implementation, this keeps 5 time values (in nanoseconds) for
each counter: total_time_enabled and total_time_running are used when
the counter is in state OFF or ERROR and for reporting back to
userspace. When the counter is in state INACTIVE or ACTIVE, it is the
tstamp_enabled, tstamp_running and tstamp_stopped values that are
relevant, and total_time_enabled and total_time_running are determined
from them. (tstamp_stopped is only used in INACTIVE state.) The
reason for doing it like this is that it means that only counters
being enabled or disabled at sched-in and sched-out time need to be
updated. There are no new loops that iterate over all counters to
update total_time_enabled or total_time_running.
This also keeps separate child_total_time_running and
child_total_time_enabled fields that get added in when reporting the
totals to userspace. They are separate fields so that they can be
atomic. We don't want to use atomics for total_time_running,
total_time_enabled etc., because then we would have to use atomic
sequences to update them, which are slower than regular arithmetic and
memory accesses.
It is possible to measure total_time_running by adding a task_clock
counter to each group of counters, and total_time_enabled can be
measured approximately with a top-level task_clock counter (though
inaccuracies will creep in if you need to disable and enable groups
since it is not possible in general to disable/enable the top-level
task_clock counter simultaneously with another group). However, that
adds extra overhead - I measured around 15% increase in the context
switch latency reported by lat_ctx (from lmbench) when a task_clock
counter was added to each of 2 groups, and around 25% increase when a
task_clock counter was added to each of 4 groups. (In both cases a
top-level task-clock counter was also added.)
In contrast, the code added in this commit gives better information
with no overhead that I could measure (in fact in some cases I
measured lower times with this code, but the differences were all less
than one standard deviation).
[ v2: address review comments by Andrew Morton. ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Orig-LKML-Reference: <18890.6578.728637.139402@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
