Earlier without cpuidle framework on pseries, the native arch
idle routine comprised of both snooze and nap
states. smt_snooze_delay variable was used to delay
the idle process entry to deeper idle state like nap.
With the coming of cpuidle, this arch specific idle was replaced
by two different idle routines, one for supporting snooze and other
for nap. This enabled addition of more
low level idle states on pseries in the future.
On adopting the generic cpuidle framework for POWER systems,
the decision of which idle state to choose from, given a predicted
idle time is taken by the menu governor based on
target_residency and exit_latency of the idle states.
target_residency is the minimum time to be resident in that idle state.
Exit_latency is time taken to exit out of idle state.
Deeper the idle state, both the target residency and exit latency
would be higher.
In the current design, smt_snooze_delay is used as target_residency
for the snooze state which is incorrect, as it is not the
minimum but the maximum duration to be in snooze state.
This would result in the governor in taking bad decision,
as presently target_residency of nap < target_residency of snooze
inspite of nap being deeper idle state.
This patch aims to fix this problem by replacing the smt_snooze_delay loop
in snooze state, with the need_resched() as the governor is aware of
entry and exit of various idle transitions based on which
next idle time prediction.
The governor is intelligent enough to determine the idle state the needs to
be transitioned to and maintains a whole of heuristics including
io load, previous idle states predictions etc for the same, based on
which idle state entry decision is taken.
With this fix, of setting target_residency of snooze to 0
nap to smt_snooze_delay
if the predicted idle time is less
than smt_snooze_delay (target_residency of nap)
value governor would pick snooze state, else nap. This adhers to the
previous native idle design.
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
smt_snooze_delay was designed to delay idle loop's nap entry
in the native idle code before it got ported over to use as part of
the cpuidle framework.
A -ve value assigned to smt_snooze_delay should result in
busy looping, in other words disabling the entry to nap state.
- https://lists.ozlabs.org/pipermail/linuxppc-dev/2010-May/082450.html
This particular functionality can be achieved currently by
echo 1 > /sys/devices/system/cpu/cpu*/state1/disable
but it is broken when one assigns -ve value to the smt_snooze_delay
variable either via sysfs entry or ppc64_cpu util.
This patch aims to fix this, by disabling nap state when smt_snooze_delay
variable is set to -ve value.
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Remove the redundant target residency initialisation in pseries_cpuidle_driver_init().
This is currently over-writing the residency time updated as part of the static
table, resulting in all the idle states having the same target
residency of 100us which is incorrect. This may result in the menu governor making
wrong state decisions.
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Fix build failure for powerpc KVM by adding missing VPN_SHIFT definition
and the ';'
arch/powerpc/kvm/book3s_32_mmu_host.c: In function 'kvmppc_mmu_map_page':
arch/powerpc/kvm/book3s_32_mmu_host.c:176: error: 'VPN_SHIFT' undeclared (first use in this function)
arch/powerpc/kvm/book3s_32_mmu_host.c:176: error: (Each undeclared identifier is reported only once
arch/powerpc/kvm/book3s_32_mmu_host.c:176: error: for each function it appears in.)
arch/powerpc/kvm/book3s_32_mmu_host.c:178: error: expected ';' before 'next_pteg'
arch/powerpc/kvm/book3s_32_mmu_host.c:190: error: label 'next_pteg' used but not defined
make[1]: *** [arch/powerpc/kvm/book3s_32_mmu_host.o] Error 1
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull sparc fixes from David Miller:
"Two sparc64 perf bug fixes and add a sysrq facility so I can diagnose
these kinds of problems more quickly in the future."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc64: Fix bit twiddling in sparc_pmu_enable_event().
sparc64: Add global PMU register dumping via sysrq.
sparc64: Like x86 we should check current->mm during perf backtrace generation.
Pull SuperH updates from Paul Mundt.
The bulk of this is the UAPI disintegration for SH.
* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
sh: Fix up more fallout from pointless ARM __iomem churn.
sh: Wire up kcmp syscall.
UAPI: (Scripted) Disintegrate arch/sh/include/asm
Add __pminitconst to fix the build, otherwise the following error can occur:
arch/frv/kernel/setup.c:187:47: error: expected '=', ',', ';', 'asm' or '__attribute__' before '*' token
arch/frv/kernel/setup.c:386:2: error: 'clock_cmodes' undeclared (first use in this function)
arch/frv/kernel/setup.c:571:6: error: 'clock_cmodes' undeclared (first use in this function)
make[2]: *** [arch/frv/kernel/setup.o] Error 1
http://kisskb.ellerman.id.au/kisskb/buildresult/7344691/
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix an incorrect symbol in copy_thread():
arch/frv/kernel/process.c: In function 'copy_thread':
arch/frv/kernel/process.c:197: error: 'chilregs' undeclared (first use in this function)
arch/frv/kernel/process.c:197: error: (Each undeclared identifier is reported only once
arch/frv/kernel/process.c:197: error: for each function it appears in.)
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix VLIW packing constraint violation in entry.S:
arch/frv/kernel/entry.S: Assembler messages:
arch/frv/kernel/entry.S:871: Error: VLIW packing constraint violation
When packing CALLL with OR, CALLL must go in the first slot. The
instructions are executed simultaneously, so it doesn't matter which way
round they're packed from that point of view.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull pinctrl fixes from Linus Walleij:
"A number of pinctrl fixes for the v3.7 series:
- duplicate includes, section markup, code mishaps
- erroneous return value in errorpath on the bcm2835 driver
- remove an unused sirf function that was causing build errors
- multiple-platform compilation stubs and a missed code review
comment fixup on the nomadik pin controller"
* tag 'pinctrl-fixes-v3.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl/nomadik: always use the simple irqdomain
pinctrl/nomadik: provide stubs for legacy Nomadik
pinctrl: remove duplicated include from pinctrl-xway.c
pinctrl: sirf: remove sirfsoc_gpio_set_pull function
pinctrl: fix return value in bcm2835_pinctrl_probe()
pinctrl: remove duplicated include from pinctrl-bcm2835.c
pinctrl: bcm2835: Use existing pointer to struct device
pinctrl: samsung: use __devinit section for init code
There was a serious disconnect in the logic happening in
sparc_pmu_disable_event() vs. sparc_pmu_enable_event().
Event disable is implemented by programming a NOP event into the PCR.
However, event enable was not reversing this operation. Instead, it
was setting the User/Priv/Hypervisor trace enable bits.
That's not sparc_pmu_enable_event()'s job, that's what
sparc_pmu_enable() and sparc_pmu_disable() do .
The intent of sparc_pmu_enable_event() is clear, since it first clear
out the event type encoding field. So fix this by OR'ing in the event
encoding rather than the trace enable bits.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit fe04ddf7c2 ("kbuild: Do not package /boot and /lib in make
tar-pkg") accidentally reverted two previous kbuild commits. I don't
know what I was thinking.
This brings back changes made by commits 24cc7fb69a ("x86/kbuild:
archscripts depends on scripts_basic") and c1c1a59e37 ("firmware: fix
directory creation rule matching with make 3.80")
Reported-by: Jan Beulich <JBeulich@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Mack reports an oops at boot with the latest kernels:
Internal error: Oops - undefined instruction: 0 [#1] SMP THUMB2
Modules linked in:
CPU: 0 Not tainted (3.6.0-11057-g584df1d #145)
PC is at cpsw_probe+0x45a/0x9ac
LR is at trace_hardirqs_on_caller+0x8f/0xfc
pc : [<c03493de>] lr : [<c005e81f>] psr: 60000113
sp : cf055fb0 ip : 00000000 fp : 00000000
r10: 00000000 r9 : 00000000 r8 : 00000000
r7 : 00000000 r6 : 00000000 r5 : c0344555 r4 : 00000000
r3 : cf057a40 r2 : 00000000 r1 : 00000001 r0 : 00000000
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 50c5387d Table: 8f3f4019 DAC: 00000015
Process init (pid: 1, stack limit = 0xcf054240)
Stack: (0xcf055fb0 to 0xcf056000)
5fa0: 00000001 00000000 00000000 00000000
5fc0: cf055fb0 c000d1a8 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 be9b3f10 00000000 b6f6add0 00000010 00000000 aaaabfaf a8babbaa
The analysis of this is as follows. In init/main.c, we issue:
kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
This creates a new thread, which falls through to the ret_from_fork
assembly, with r4 set NULL and r5 set to kernel_init. You can see
this in your oops dump register set - r5 is 0xc0344555, which is the
address of kernel_init plus 1 which marks the function as Thumb code.
Now, let's look at this code a little closer - this is what the
disassembly looks like:
c000d180 <ret_from_fork>:
c000d180: f03a fe08 bl c0047d94 <schedule_tail>
c000d184: 2d00 cmp r5, #0
c000d186: bf1e ittt ne
c000d188: 4620 movne r0, r4
c000d18a: 46fe movne lr, pc <-- XXXXXXX
c000d18c: 46af movne pc, r5
c000d18e: 46e9 mov r9, sp
c000d190: ea4f 3959 mov.w r9, r9, lsr #13
c000d194: ea4f 3949 mov.w r9, r9, lsl #13
c000d198: e7c8 b.n c000d12c <ret_to_user>
c000d19a: bf00 nop
c000d19c: f3af 8000 nop.w
This code was introduced in 9fff2fa0db (arm: switch to saner
kernel_execve() semantics). I have marked one instruction, and it's
the significant one - I'll come back to that later.
Eventually, having had a successful call to kernel_execve(), kernel_init()
returns zero.
In returning, it uses the value in 'lr' which was set by the instruction
I marked above. Unfortunately, this causes lr to contain 0xc000d18e -
an even address. This switches the ISA to ARM on return but with a non
word aligned PC value.
So, what do we end up executing? Well, not the instructions above - yes
the opcodes, but they don't mean the same thing in ARM mode. In ARM mode,
it looks like this instead:
c000d18c: 46e946af strbtmi r4, [r9], pc, lsr #13
c000d190: 3959ea4f ldmdbcc r9, {r0, r1, r2, r3, r6, r9, fp, sp, lr, pc}^
c000d194: 3949ea4f stmdbcc r9, {r0, r1, r2, r3, r6, r9, fp, sp, lr, pc}^
c000d198: bf00e7c8 svclt 0x0000e7c8
c000d19c: 8000f3af andhi pc, r0, pc, lsr #7
c000d1a0: e88db092 stm sp, {r1, r4, r7, ip, sp, pc}
c000d1a4: 46e81fff ; <UNDEFINED> instruction: 0x46e81fff
c000d1a8: 8a00f3ef bhi 0xc004a16c
c000d1ac: 0a0cf08a beq 0xc03493dc
I have included more above, because it's relevant. The PSR flags which
we can see in the oops dump are nZCv, so Z and C are set.
All the above ARM instructions are not executed, except for two.
c000d1a0, which has no writeback, and writes below the current stack
pointer (and that data is lost when we take the next exception.) The
other instruction which is executed is c000d1ac, which takes us to...
0xc03493dc. However, remember that bit 1 of the PC got set. So that
makes the PC value 0xc03493de.
And that value is the value we find in the oops dump for PC. What is
the instruction here when interpreted in ARM mode?
0: f71e150c ; <UNDEFINED> instruction: 0xf71e150c
and there we have our undefined instruction (remember that the 'never'
condition code, 0xf, has been deprecated and is now always executed as
it is now being used for additional instructions.)
This path also nicely explains the state of the stack we see in the oops
dump too.
The above is a consistent and sane story for how we got to the oops
dump, which all stems from the instruction at 0xc000d18a being wrong.
Reported-by: Daniel Mack <zonque@gmail.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The prima2 platform advertises needing no mach/gpio.h header file,
but its pinctrl driver now has a sirfsoc_gpio_set_pull function
that uses constants defined in arch/arm/mach-prima2/include/mach/gpio.h,
which fails to build.
Fortunately, the sirfsoc_gpio_set_pull is not used anywhere in the
kernel, so we can safely remove it. Any out of tree drivers using
it will have to be converted to use proper pinctrl functions to
do the same.
Without this patch, building prima2_defconfig results in:
drivers/pinctrl/pinctrl-sirf.c: In function 'sirfsoc_gpio_set_pull':
drivers/pinctrl/pinctrl-sirf.c:1331:7: error: 'SIRFSOC_GPIO_PULL_NONE' undeclared (first use in this function)
drivers/pinctrl/pinctrl-sirf.c:1331:7: note: each undeclared identifier is reported only once for each function it appears in
drivers/pinctrl/pinctrl-sirf.c:1334:7: error: 'SIRFSOC_GPIO_PULL_UP' undeclared (first use in this function)
drivers/pinctrl/pinctrl-sirf.c:1338:7: error: 'SIRFSOC_GPIO_PULL_DOWN' undeclared (first use in this function)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Pull MIPS update from Ralf Baechle:
"Cleanups and fixes for breakage that occured earlier during this merge
phase. Also a few patches that didn't make the first pull request.
Of those is the Alchemy work that merges code for many of the SOCs and
evaluation boards thus among other code shrinkage, reduces the number
of MIPS defconfigs by 5."
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (22 commits)
MIPS: SNI: Switch RM400 serial to SCCNXP driver
MIPS: Remove unused empty_bad_pmd_table[] declaration.
MIPS: MT: Remove kspd.
MIPS: Malta: Fix section mismatch.
MIPS: asm-offset.c: Delete unused irq_cpustat_t struct offsets.
MIPS: Alchemy: Merge PB1100/1500 support into DB1000 code.
MIPS: Alchemy: merge PB1550 support into DB1550 code
MIPS: Alchemy: Single kernel for DB1200/1300/1550
MIPS: Optimize TLB refill for RI/XI configurations.
MIPS: proc: Cleanup printing of ASEs.
MIPS: Hardwire detection of DSP ASE Rev 2 for systems, as required.
MIPS: Add detection of DSP ASE Revision 2.
MIPS: Optimize pgd_init and pmd_init
MIPS: perf: Add perf functionality for BMIPS5000
MIPS: perf: Split the Kconfig option CONFIG_MIPS_MT_SMP
MIPS: perf: Remove unnecessary #ifdef
MIPS: perf: Add cpu feature bit for PCI (performance counter interrupt)
MIPS: perf: Change the "mips_perf_event" table unsupported indicator.
MIPS: Align swapper_pg_dir to 64K for better TLB Refill code.
vmlinux.lds.h: Allow architectures to add sections to the front of .bss
...
Pull module signing support from Rusty Russell:
"module signing is the highlight, but it's an all-over David Howells frenzy..."
Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG.
* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits)
X.509: Fix indefinite length element skip error handling
X.509: Convert some printk calls to pr_devel
asymmetric keys: fix printk format warning
MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking
MODSIGN: Make mrproper should remove generated files.
MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs
MODSIGN: Use the same digest for the autogen key sig as for the module sig
MODSIGN: Sign modules during the build process
MODSIGN: Provide a script for generating a key ID from an X.509 cert
MODSIGN: Implement module signature checking
MODSIGN: Provide module signing public keys to the kernel
MODSIGN: Automatically generate module signing keys if missing
MODSIGN: Provide Kconfig options
MODSIGN: Provide gitignore and make clean rules for extra files
MODSIGN: Add FIPS policy
module: signature checking hook
X.509: Add a crypto key parser for binary (DER) X.509 certificates
MPILIB: Provide a function to read raw data into an MPI
X.509: Add an ASN.1 decoder
X.509: Add simple ASN.1 grammar compiler
...
The hostprogs need access to the CONFIG_* symbols found in
include/generated/autoconf.h. But commit abbf1590de ("UAPI: Partition
the header include path sets and add uapi/ header directories") replaced
$(LINUXINCLUDE) with $(USERINCLUDE) which doesn't contain the necessary
include paths.
This has the undesirable effect of breaking the EFI boot stub because
the #ifdef CONFIG_EFI_STUB code in arch/x86/boot/tools/build.c is
never compiled.
It should also be noted that because $(USERINCLUDE) isn't exported by
the top-level Makefile it's actually empty in arch/x86/boot/Makefile.
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull ARM update from Russell King:
"This is the final round of stuff for ARM, left until the end of the
merge window to reduce the number of conflicts. This set contains the
ARM part of David Howells UAPI changes, and a fix to the ordering of
'select' statements in ARM Kconfig files (see the appropriate commit
for why this happened - thanks to Andrew Morton for pointing out the
problem.)
I've left this as long as I dare for this window to avoid conflicts,
and I regenerated the config patch yesterday, posting it to our
mailing list for review and testing. I have several acks which
include successful test reports for it.
However, today I notice we've got new conflicts with previously unseen
code... though that conflict should be trivial (it's my changes vs a
one liner.)"
* 'late-for-linus' of git://git.linaro.org/people/rmk/linux-arm:
ARM: config: make sure that platforms are ordered by option string
ARM: config: sort select statements alphanumerically
UAPI: (Scripted) Disintegrate arch/arm/include/asm
Fix up fairly conflict in arch/arm/Kconfig (the select re-organization
vs recent addition of GENERIC_KERNEL_EXECVE)
Deepthi Dharwar
Aneesh Kumar K.V
Benjamin Herrenschmidt
Linus Torvalds
Andi Kleen
David Howells
David S. Miller
Michal Marek
Russell King
Arnd Bergmann
Paul Mundt
Matt Fleming