Commit Graph

20722 Commits

Author SHA1 Message Date
Simon Guo
533082ae86 KVM: PPC: Book3S PR: Emulate mtspr/mfspr using active TM SPRs
The mfspr/mtspr on TM SPRs(TEXASR/TFIAR/TFHAR) are non-privileged
instructions and can be executed by PR KVM guest in problem state
without trapping into the host. We only emulate mtspr/mfspr
texasr/tfiar/tfhar in guest PR=0 state.

When we are emulating mtspr tm sprs in guest PR=0 state, the emulation
result needs to be visible to guest PR=1 state. That is, the actual TM
SPR val should be loaded into actual registers.

We already flush TM SPRs into vcpu when switching out of CPU, and load
TM SPRs when switching back.

This patch corrects mfspr()/mtspr() emulation for TM SPRs to make the
actual source/dest be the actual TM SPRs.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:30:05 +10:00
Simon Guo
13989b65eb KVM: PPC: Book3S PR: Add math support for PR KVM HTM
The math registers will be saved into vcpu->arch.fp/vr and corresponding
vcpu->arch.fp_tm/vr_tm area.

We flush or giveup the math regs into vcpu->arch.fp/vr before saving
transaction. After transaction is restored, the math regs will be loaded
back into regs.

If there is a FP/VEC/VSX unavailable exception during transaction active
state, the math checkpoint content might be incorrect and we need to do
treclaim./load the correct checkpoint val/trechkpt. sequence to retry the
transaction. That will make our solution complicated. To solve this issue,
we always make the hardware guest MSR math bits (shadow_msr) consistent
with the MSR val which guest sees (kvmppc_get_msr()) when guest msr is
with tm enabled. Then all FP/VEC/VSX unavailable exception can be delivered
to guest and guest handles the exception by itself.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:30:00 +10:00
Simon Guo
8d2e2fc5e0 KVM: PPC: Book3S PR: Add transaction memory save/restore skeleton
The transaction memory checkpoint area save/restore behavior is
triggered when VCPU qemu process is switching out/into CPU, i.e.
at kvmppc_core_vcpu_put_pr() and kvmppc_core_vcpu_load_pr().

MSR TM active state is determined by TS bits:
    active: 10(transactional) or 01 (suspended)
    inactive: 00 (non-transactional)
We don't "fake" TM functionality for guest. We "sync" guest virtual
MSR TM active state(10 or 01) with shadow MSR. That is to say,
we don't emulate a transactional guest with a TM inactive MSR.

TM SPR support(TFIAR/TFAR/TEXASR) has already been supported by
commit 9916d57e64 ("KVM: PPC: Book3S PR: Expose TM registers").
Math register support (FPR/VMX/VSX) will be done at subsequent
patch.

Whether TM context need to be saved/restored can be determined
by kvmppc_get_msr() TM active state:
	* TM active - save/restore TM context
	* TM inactive - no need to do so and only save/restore
TM SPRs.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:55 +10:00
Simon Guo
66c33e796c KVM: PPC: Book3S PR: Add kvmppc_save/restore_tm_sprs() APIs
This patch adds 2 new APIs, kvmppc_save_tm_sprs() and
kvmppc_restore_tm_sprs(), for the purpose of TEXASR/TFIAR/TFHAR
save/restore.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:51 +10:00
Simon Guo
de7ad93219 KVM: PPC: Book3S PR: Add new kvmppc_copyto/from_vcpu_tm APIs
This patch adds 2 new APIs: kvmppc_copyto_vcpu_tm() and
kvmppc_copyfrom_vcpu_tm().  These 2 APIs will be used to copy from/to TM
data between VCPU_TM/VCPU area.

PR KVM will use these APIs for treclaim. or trechkpt. emulation.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:47 +10:00
Simon Guo
36383a0862 KVM: PPC: Book3S PR: Avoid changing TS bits when exiting guest
PR KVM host usually runs with TM enabled in its host MSR value, and
with non-transactional TS value.

When a guest with TM active traps into PR KVM host, the rfid at the
tail of kvmppc_interrupt_pr() will try to switch TS bits from
S0 (Suspended & TM disabled) to N1 (Non-transactional & TM enabled).

That will leads to TM Bad Thing interrupt.

This patch manually sets target TS bits unchanged to avoid this
exception.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:42 +10:00
Simon Guo
401a89e937 KVM: PPC: Book3S PR: Implement RFID TM behavior to suppress change from S0 to N0
According to ISA specification for RFID, in MSR TM disabled and TS
suspended state (S0), if the target MSR is TM disabled and TS state is
inactive (N0), rfid should suppress this update.

This patch makes the RFID emulation of PR KVM consistent with this.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:38 +10:00
Simon Guo
95757bfc72 KVM: PPC: Book3S PR: Sync TM bits to shadow msr for problem state guest
MSR TS bits can be modified with non-privileged instruction such as
tbegin./tend.  That means guest can change MSR value "silently" without
notifying host.

It is necessary to sync the TM bits to host so that host can calculate
shadow msr correctly.

Note, privileged mode in the guest will always fail transactions so we
only take care of problem state mode in the guest.

The logic is put into kvmppc_copy_from_svcpu() so that
kvmppc_handle_exit_pr() can use correct MSR TM bits even when preemption
occurs.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:33 +10:00
Simon Guo
901938add3 KVM: PPC: Book3S PR: Pass through MSR TM and TS bits to shadow_msr
PowerPC TM functionality needs MSR TM/TS bits support in hardware level.
Guest TM functionality can not be emulated with "fake" MSR (msr in magic
page) TS bits.

This patch syncs TM/TS bits in shadow_msr with the MSR value in magic
page, so that the MSR TS value which guest sees is consistent with actual
MSR bits running in guest.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:28 +10:00
Simon Guo
25ddda07b6 KVM: PPC: Book3S PR: Transition to Suspended state when injecting interrupt
This patch simulates interrupt behavior per Power ISA while injecting
interrupt in PR KVM:
- When interrupt happens, transactional state should be suspended.

kvmppc_mmu_book3s_64_reset_msr() will be invoked when injecting an
interrupt. This patch performs this ISA logic in
kvmppc_mmu_book3s_64_reset_msr().

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:22 +10:00
Simon Guo
caa3be92be KVM: PPC: Book3S PR: Add C function wrapper for _kvmppc_save/restore_tm()
Currently __kvmppc_save/restore_tm() APIs can only be invoked from
assembly function. This patch adds C function wrappers for them so
that they can be safely called from C function.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:17 +10:00
Simon Guo
7f386af7bd KVM: PPC: Book3S PR: Turn on FP/VSX/VMX MSR bits in kvmppc_save_tm()
kvmppc_save_tm() invokes store_fp_state/store_vr_state(). So it is
mandatory to turn on FP/VSX/VMX MSR bits for its execution, just
like what kvmppc_restore_tm() did.

Previously HV KVM has turned the bits on outside of function
kvmppc_save_tm().  Now we include this bit change in kvmppc_save_tm()
so that the logic is cleaner. And PR KVM can reuse it later.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:29:12 +10:00
Simon Guo
6f597c6b63 KVM: PPC: Book3S PR: Add guest MSR parameter for kvmppc_save_tm()/kvmppc_restore_tm()
HV KVM and PR KVM need different MSR source to indicate whether
treclaim. or trecheckpoint. is necessary.

This patch add new parameter (guest MSR) for these kvmppc_save_tm/
kvmppc_restore_tm() APIs:
- For HV KVM, it is VCPU_MSR
- For PR KVM, it is current host MSR or VCPU_SHADOW_SRR1

This enhancement enables these 2 APIs to be reused by PR KVM later.
And the patch keeps HV KVM logic unchanged.

This patch also reworks kvmppc_save_tm()/kvmppc_restore_tm() to
have a clean ABI: r3 for vcpu and r4 for guest_msr.

During kvmppc_save_tm/kvmppc_restore_tm(), the R1 need to be saved
or restored. Currently the R1 is saved into HSTATE_HOST_R1. In PR
KVM, we are going to add a C function wrapper for
kvmppc_save_tm/kvmppc_restore_tm() where the R1 will be incremented
with added stackframe and save into HSTATE_HOST_R1. There are several
places in HV KVM to load HSTATE_HOST_R1 as R1, and we don't want to
bring risk or confusion by TM code.

This patch will use HSTATE_SCRATCH2 to save/restore R1 in
kvmppc_save_tm/kvmppc_restore_tm() to avoid future confusion, since
the r1 is actually a temporary/scratch value to be saved/stored.

[paulus@ozlabs.org - rebased on top of 7b0e827c69 ("KVM: PPC: Book3S HV:
 Factor fake-suspend handling out of kvmppc_save/restore_tm", 2018-05-30)]

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:27:59 +10:00
Simon Guo
009c872a8b KVM: PPC: Book3S PR: Move kvmppc_save_tm/kvmppc_restore_tm to separate file
It is a simple patch just for moving kvmppc_save_tm/kvmppc_restore_tm()
functionalities to tm.S. There is no logic change. The reconstruct of
those APIs will be done in later patches to improve readability.

It is for preparation of reusing those APIs on both HV/PR PPC KVM.

Some slight change during move the functions includes:
- surrounds some HV KVM specific code with CONFIG_KVM_BOOK3S_HV_POSSIBLE
for compilation.
- use _GLOBAL() to define kvmppc_save_tm/kvmppc_restore_tm()

[paulus@ozlabs.org - rebased on top of 7b0e827c69 ("KVM: PPC: Book3S HV:
 Factor fake-suspend handling out of kvmppc_save/restore_tm", 2018-05-30)]

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-31 11:35:12 +10:00
Paul Mackerras
43b812d9ab Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the ppc-kvm topic branch of the powerpc repository
to get some changes on which future patches will depend, in particular
some new exports and TEXASR bit definitions.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-31 09:27:10 +10:00
Paul Mackerras
7b0e827c69 KVM: PPC: Book3S HV: Factor fake-suspend handling out of kvmppc_save/restore_tm
This splits out the handling of "fake suspend" mode, part of the
hypervisor TM assist code for POWER9, and puts almost all of it in
new kvmppc_save_tm_hv and kvmppc_restore_tm_hv functions.  The new
functions branch to kvmppc_save/restore_tm if the CPU does not
require hypervisor TM assistance.

With this, it will be more straightforward to move kvmppc_save_tm and
kvmppc_restore_tm to another file and use them for transactional
memory support in PR KVM.  Additionally, it also makes the code a
bit clearer and reduces the number of feature sections.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-31 09:23:28 +10:00
Paul Mackerras
9617a0b335 KVM: PPC: Book3S PR: Allow KVM_PPC_CONFIGURE_V3_MMU to succeed
Currently, PR KVM does not implement the configure_mmu operation, and
so the KVM_PPC_CONFIGURE_V3_MMU ioctl always fails with an EINVAL
error.  This causes recent kernels to fail to boot as a PR KVM guest
on POWER9, since recent kernels booted in HPT mode do the
H_REGISTER_PROC_TBL hypercall, which causes userspace (QEMU) to do
KVM_PPC_CONFIGURE_V3_MMU, which fails.

This implements a minimal configure_mmu operation for PR KVM.  It
succeeds only if the MMU is being configured for HPT mode and no
process table is being registered.  This is enough to get recent
kernels to boot as a PR KVM guest.

Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-31 09:21:50 +10:00
Aneesh Kumar K.V
5e3f0d15ae powerpc/livepatch: Fix build error with kprobes disabled.
arch/powerpc/kernel/stacktrace.c: In function ‘save_stack_trace_tsk_reliable’:
arch/powerpc/kernel/stacktrace.c:176:28: error: ‘kretprobe_trampoline’ undeclared
   if (ip == (unsigned long)kretprobe_trampoline)
                            ^~~~~~~~~~~~~~~~~~~~

Fixes: df78d3f614 ("powerpc/livepatch: Implement reliable stack tracing for the consistency model")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-29 11:10:39 +10:00
Josh Poimboeuf
8ce621e1d9 powerpc/modules: remove unused mod_arch_specific.toc field
The toc field in the mod_arch_specific struct isn't actually used
anywhere, so remove it.

Also the ftrace-specific fields are now common between 32-bit and
64-bit, so simplify the struct definition a bit by moving them out of
the __powerpc64__ #ifdef.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-28 18:46:34 +10:00
Akshay Adiga
ac9816dcba powerpc/powernv/cpuidle: Init all present cpus for deep states
Init all present cpus for deep states instead of "all possible" cpus.
Init fails if a possible cpu is guarded. Resulting in making only
non-deep states available for cpuidle/hotplug.

Stewart says, this means that for single threaded workloads, if you
guard out a CPU core you'll not get WoF (Workload Optimised
Frequency), which means that performance goes down when you wouldn't
expect it to.

Fixes: 77b54e9f21 ("powernv/powerpc: Add winkle support for offline cpus")
Cc: stable@vger.kernel.org # v3.19+
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-28 18:46:33 +10:00
David S. Miller
5b79c2af66 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of easy overlapping changes in the confict
resolutions here.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-26 19:46:15 -04:00
Linus Torvalds
ec30dcf7f4 Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář:
 "PPC:

   - Close a hole which could possibly lead to the host timebase getting
     out of sync.

   - Three fixes relating to PTEs and TLB entries for radix guests.

   - Fix a bug which could lead to an interrupt never getting delivered
     to the guest, if it is pending for a guest vCPU when the vCPU gets
     offlined.

  s390:

   - Fix false negatives in VSIE validity check (Cc stable)

  x86:

   - Fix time drift of VMX preemption timer when a guest uses LAPIC
     timer in periodic mode (Cc stable)

   - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow
     migration from hosts that don't need retpoline mitigation (Cc
     stable)

   - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and
     CPUID.OSXSAVE (Cc stable)

   - Report correct RIP after Hyper-V hypercall #UD (introduced in
     -rc6)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: fix #UD address of failed Hyper-V hypercalls
  kvm: x86: IA32_ARCH_CAPABILITIES is always supported
  KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
  x86/kvm: fix LAPIC timer drift when guest uses periodic mode
  KVM: s390: vsie: fix < 8k check for the itdba
  KVM: PPC: Book 3S HV: Do ptesync in radix guest exit path
  KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority change
  KVM: PPC: Book3S HV: Make radix clear pte when unmapping
  KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in kvmppc_radix_tlbie_page
  KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry
2018-05-26 10:46:57 -07:00
Linus Torvalds
b133ef6ea4 Merge tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
 "Just one fix, to make sure the PCR (Processor Compatibility Register)
  is reset on boot.

  Otherwise if we're running in compat mode in a guest (eg. pretending a
  Power9 is a Power8) and the host kernel oopses and kdumps then the
  kdump kernel's userspace will be running in Power8 mode, and will
  SIGILL if it uses Power9-only instructions.

  Thanks to Michael Neuling"

* tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Clear PCR on boot
2018-05-25 09:32:00 -07:00
Madhavan Srinivasan
458c70173d powerpc/perf: Update raw-event code encoding comment for power8
Comment explanning the raw event code encoding for Power8 was
moved to isa207_common.h file when re-factoring the code to
support power9. But then Power9 pmu branched out due to changes
specific to power9. So move the encoding comment back to power8-pmu.c
Just comment movement and no logic change.

Fixes: 4d3576b207 ('powerpc/perf: factor out power8 pmu macros and defines')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 17:49:01 +10:00
David S. Miller
90fed9c946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2018-05-24

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Björn Töpel cleans up AF_XDP (removes rebind, explicit cache alignment from uapi, etc).

2) David Ahern adds mtu checks to bpf_ipv{4,6}_fib_lookup() helpers.

3) Jesper Dangaard Brouer adds bulking support to ndo_xdp_xmit.

4) Jiong Wang adds support for indirect and arithmetic shifts to NFP

5) Martin KaFai Lau cleans up BTF uapi and makes the btf_header extensible.

6) Mathieu Xhonneux adds an End.BPF action to seg6local with BPF helpers allowing
   to edit/grow/shrink a SRH and apply on a packet generic SRv6 actions.

7) Sandipan Das adds support for bpf2bpf function calls in ppc64 JIT.

8) Yonghong Song adds BPF_TASK_FD_QUERY command for introspection of tracing events.

9) other misc fixes from Gustavo A. R. Silva, Sirio Balmelli, John Fastabend, and Magnus Karlsson
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24 22:20:51 -04:00
Mathieu Malaterre
d647b210ac powerpc: Add a missing include header
The header file <asm/switch_to.h> was missing from the includes. Fix the
following warning, treated as error with W=1:

  arch/powerpc/kernel/vecemu.c:260:5: error: no previous prototype for ‘emulate_altivec’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:46 +10:00
Mathieu Malaterre
c89ca59322 powerpc/32: Add a missing include header
The header file <linux/syscalls.h> was missing from the includes. Fix the
following warning, treated as error with W=1:

  arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:46 +10:00
Mathieu Malaterre
b87a358b4a powerpc/chrp/time: Make some functions static, add missing header include
Add a missing include <platforms/chrp/chrp.h>.

These functions can all be static, make it so. Fix warnings treated as
errors with W=1:

  arch/powerpc/platforms/chrp/time.c:41:13: error: no previous prototype for ‘chrp_time_init’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/time.c:66:5: error: no previous prototype for ‘chrp_cmos_clock_read’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/time.c:74:6: error: no previous prototype for ‘chrp_cmos_clock_write’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/time.c:86:5: error: no previous prototype for ‘chrp_set_rtc_time’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/time.c:130:6: error: no previous prototype for ‘chrp_get_rtc_time’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:45 +10:00
Mathieu Malaterre
9e0d86cd2d powerpc/tau: Make some function static
These functions can all be static, make it so. Fix warnings treated as
errors with W=1:

  arch/powerpc/kernel/tau_6xx.c:53:6: error: no previous prototype for ‘set_thresholds’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:73:6: error: no previous prototype for ‘TAUupdate’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:208:13: error: no previous prototype for ‘TAU_init_smp’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:220:12: error: no previous prototype for ‘TAU_init’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:126:6: error: no previous prototype for ‘TAUException’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:44 +10:00
Mathieu Malaterre
86e11b6e9c powerpc: Make function btext_initialize static
This function can be static, make it so, this fix a warning treated as
error with W=1:

  arch/powerpc/kernel/btext.c:173:5: error: no previous prototype for ‘btext_initialize’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:44 +10:00
Mathieu Malaterre
bd13ac95f9 powerpc/tau: Synchronize function prototypes and body
Some function prototypes and body for Thermal Assist Units were not in
sync. Update the function definition to match the existing function
declaration found in `setup-common.c`, changing an `int` return type to a
`u32` return type. Move the prototypes to a header file. Fix the following
warnings, treated as error with W=1:

  arch/powerpc/kernel/tau_6xx.c:257:5: error: no previous prototype for ‘cpu_temp_both’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:262:5: error: no previous prototype for ‘cpu_temp’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:267:5: error: no previous prototype for ‘tau_interrupts’ [-Werror=missing-prototypes]

Compile tested with CONFIG_TAU_INT.

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:43 +10:00
Mathieu Malaterre
3fc5ee9b28 powerpc: Add missing prototype
Add one missing prototype for function rh_dump_blk. Fix warning treated as
error in W=1:

  arch/powerpc/lib/rheap.c:740:6: error: no previous prototype for ‘rh_dump_blk’ [-Werror=missing-prototypes]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:43 +10:00
Mathieu Malaterre
c3f0515ea1 powerpc/52xx: Add missing functions prototypes
The function prototypes were declared within a `#ifdef CONFIG_PPC_LITE5200`
block which would prevent them from being visible when compiling
`mpc52xx_pm.c`. Move the prototypes outside of the `#ifdef` block to fix
the following warnings treated as errors with W=1:

  arch/powerpc/platforms/52xx/mpc52xx_pm.c:58:5: error: no previous prototype for ‘mpc52xx_pm_prepare’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/52xx/mpc52xx_pm.c:113:5: error: no previous prototype for ‘mpc52xx_pm_enter’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/52xx/mpc52xx_pm.c:181:6: error: no previous prototype for ‘mpc52xx_pm_finish’ [-Werror=missing-prototypes]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:42 +10:00
Mathieu Malaterre
f72cf3f1d4 powerpc/powermac: Add missing prototype for note_bootable_part()
Add a missing prototype for function `note_bootable_part` to silence a
warning treated as error with W=1:

  arch/powerpc/platforms/powermac/setup.c:361:12: error: no previous prototype for ‘note_bootable_part’ [-Werror=missing-prototypes]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:42 +10:00
Mathieu Malaterre
f91d599899 powerpc/powermac: Move pmac_pfunc_base_install prototype to header file
The pmac_pfunc_base_install prototype was declared in powermac/smp.c since
function was used there, move it to pmac_pfunc.h header to be visible in
pfunc_base.c. Fix a warning treated as error with W=1:

  arch/powerpc/platforms/powermac/pfunc_base.c:330:12: error: no previous prototype for ‘pmac_pfunc_base_install’ [-Werror=missing-prototypes]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:41 +10:00
Mathieu Malaterre
910be6be6c powerpc/chrp/pci: Make some functions static
These functions can all be static, make it so. Fix warnings treated as
errors with W=1:

  arch/powerpc/platforms/chrp/pci.c:34:5: error: no previous prototype for ‘gg2_read_config’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/pci.c:61:5: error: no previous prototype for ‘gg2_write_config’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/pci.c:97:5: error: no previous prototype for ‘rtas_read_config’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/pci.c:112:5: error: no previous prototype for ‘rtas_write_config’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:41 +10:00
Mathieu Malaterre
5a4b475cf8 powerpc/powermac: Mark variable x as unused
Since the value of x is never intended to be read, declare it with gcc
attribute as unused. Fix warning treated as error with W=1:

  arch/powerpc/platforms/powermac/bootx_init.c:471:21: error: variable ‘x’ set but not used [-Werror=unused-but-set-variable]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:40 +10:00
Mathieu Malaterre
f0e0b86638 powerpc/chrp/setup: Remove idu_size variable and make some functions static
Remove variable declaration idu_size and associated code since not used.

These functions can all be static, make it so. Fix warnings treated as
errors with W=1:

  arch/powerpc/platforms/chrp/setup.c:97:6: error: no previous prototype for ‘chrp_show_cpuinfo’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/setup.c:302:13: error: no previous prototype for ‘chrp_setup_arch’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/setup.c:385:16: error: variable ‘idu_size’ set but not used [-Werror=unused-but-set-variable]
  arch/powerpc/platforms/chrp/setup.c:526:13: error: no previous prototype for ‘chrp_init_IRQ’ [-Werror=missing-prototypes]
  arch/powerpc/platforms/chrp/setup.c:559:1: error: no previous prototype for ‘chrp_init2’ [-Werror=missing-prototypes]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:40 +10:00
Mathieu Malaterre
eed6964bce powerpc/wii: Make hlwd_pic_init function static
The function hlwd_pic_init can be made static, so do it. Fix the following
warning treated as error (W=1):

../arch/powerpc/platforms/embedded6xx/hlwd-pic.c:158:20: error: no previous prototype for ‘hlwd_pic_init’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:39 +10:00
Mathieu Malaterre
85aa4b9841 powerpc/mm/radix: Use do/while(0) trick for single statement block
In commit 7a22d6321c ("powerpc/mm/radix: Update command line parsing for
disable_radix") an `if` statement was added for a possible empty body
(prom_debug).

Fix the following warning, treated as error with W=1:

  arch/powerpc/kernel/prom_init.c:656:46: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body]

Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:39 +10:00
Mathieu Malaterre
d8731527ac powerpc/sparse: Fix plain integer as NULL pointer warning
Trivial fix to remove the following sparse warnings:

  arch/powerpc/kernel/module_32.c:112:74: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/module_32.c:117:74: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1155:28: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1230:20: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1385:36: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1752:23: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2084:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2110:32: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2167:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2183:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:277:20: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:155:67: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:247:27: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:249:27: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:252:37: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:127:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:148:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:44:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:57:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:87:21: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:160:31: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:167:22: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:274:21: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:285:31: warning: Using plain integer as NULL pointer
  arch/powerpc/include/asm/hugetlb.h:204:16: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/ppc_mmu_32.c:170:21: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/pci.c:1227:23: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/pci.c:65:24: warning: Using plain integer as NULL pointer

Also use `--fix` command line option from `script/checkpatch --strict` to
remove the following:

  CHECK: Comparison to NULL could be written "!dispDeviceBase"
  #72: FILE: arch/powerpc/kernel/btext.c:160:
  +	if (dispDeviceBase == NULL)

  CHECK: Comparison to NULL could be written "!vbase"
  #80: FILE: arch/powerpc/kernel/btext.c:167:
  +	if (vbase == NULL)

  CHECK: Comparison to NULL could be written "!base"
  #89: FILE: arch/powerpc/kernel/btext.c:274:
  +	if (base == NULL)

  CHECK: Comparison to NULL could be written "!dispDeviceBase"
  #98: FILE: arch/powerpc/kernel/btext.c:285:
  +	if (dispDeviceBase == NULL)

  CHECK: Comparison to NULL could be written "strstr"
  #117: FILE: arch/powerpc/kernel/module_32.c:117:
  +		if (strstr(secstrings + sechdrs[i].sh_name, ".debug") != NULL)

  CHECK: Comparison to NULL could be written "!Hash"
  #130: FILE: arch/powerpc/mm/ppc_mmu_32.c:170:
  +	if (Hash == NULL)

  CHECK: Comparison to NULL could be written "Hash"
  #143: FILE: arch/powerpc/mm/tlb_hash32.c:44:
  +	if (Hash != NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #152: FILE: arch/powerpc/mm/tlb_hash32.c:57:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #161: FILE: arch/powerpc/mm/tlb_hash32.c:87:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #170: FILE: arch/powerpc/mm/tlb_hash32.c:127:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #179: FILE: arch/powerpc/mm/tlb_hash32.c:148:
  +	if (Hash == NULL) {

  ERROR: space required after that ';' (ctx:VxV)
  #192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
  +	for (; node != NULL;node = node->sibling) {

  CHECK: Comparison to NULL could be written "node"
  #192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
  +	for (; node != NULL;node = node->sibling) {

  CHECK: Comparison to NULL could be written "!region"
  #201: FILE: arch/powerpc/platforms/powermac/pci.c:1227:
  +	if (region == NULL)

  CHECK: Comparison to NULL could be written "of_get_property"
  #214: FILE: arch/powerpc/platforms/powermac/setup.c:155:
  +		if (of_get_property(np, "cache-unified", NULL) != NULL && dc) {

  CHECK: Comparison to NULL could be written "!np"
  #223: FILE: arch/powerpc/platforms/powermac/setup.c:247:
  +		if (np == NULL)

  CHECK: Comparison to NULL could be written "np"
  #226: FILE: arch/powerpc/platforms/powermac/setup.c:249:
  +		if (np != NULL) {

  CHECK: Comparison to NULL could be written "l2cr"
  #230: FILE: arch/powerpc/platforms/powermac/setup.c:252:
  +			if (l2cr != NULL) {

  CHECK: Comparison to NULL could be written "via"
  #243: FILE: drivers/macintosh/via-pmu.c:277:
  +	if (via != NULL)

  CHECK: Comparison to NULL could be written "current_req"
  #252: FILE: drivers/macintosh/via-pmu.c:1155:
  +	if (current_req != NULL) {

  CHECK: Comparison to NULL could be written "!req"
  #261: FILE: drivers/macintosh/via-pmu.c:1230:
  +	if (req == NULL || pmu_state != idle

  CHECK: Comparison to NULL could be written "!req"
  #270: FILE: drivers/macintosh/via-pmu.c:1385:
  +			if (req == NULL) {

  CHECK: Comparison to NULL could be written "!pp"
  #288: FILE: drivers/macintosh/via-pmu.c:2084:
  +	if (pp == NULL)

  CHECK: Comparison to NULL could be written "!pp"
  #297: FILE: drivers/macintosh/via-pmu.c:2110:
  +	if (count < 1 || pp == NULL)

  CHECK: Comparison to NULL could be written "!pp"
  #306: FILE: drivers/macintosh/via-pmu.c:2167:
  +	if (pp == NULL)

  CHECK: Comparison to NULL could be written "pp"
  #315: FILE: drivers/macintosh/via-pmu.c:2183:
  +	if (pp != NULL) {

Link: https://github.com/linuxppc/linux/issues/37
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:38 +10:00
Mathieu Malaterre
7cf76a68f1 powerpc/altivec: Add missing prototypes for altivec
Some functions prototypes were missing for the non-altivec code. Add the
missing prototypes in a new header file, fix warnings treated as errors
with W=1:

  arch/powerpc/lib/xor_vmx_glue.c:18:6: error: no previous prototype for ‘xor_altivec_2’ [-Werror=missing-prototypes]
  arch/powerpc/lib/xor_vmx_glue.c:29:6: error: no previous prototype for ‘xor_altivec_3’ [-Werror=missing-prototypes]
  arch/powerpc/lib/xor_vmx_glue.c:40:6: error: no previous prototype for ‘xor_altivec_4’ [-Werror=missing-prototypes]
  arch/powerpc/lib/xor_vmx_glue.c:52:6: error: no previous prototype for ‘xor_altivec_5’ [-Werror=missing-prototypes]

The prototypes were already present in <asm/xor.h> but this header file is
meant to be included after <include/linux/raid/xor.h>. Trying to re-use
<asm/xor.h> directly would lead to warnings such as:

  arch/powerpc/include/asm/xor.h:39:15: error: variable ‘xor_block_altivec’ has initializer but incomplete type

Trying to re-use <asm/xor.h> after <include/linux/raid/xor.h> in
xor_vmx_glue.c would in turn trigger the following warnings:

  include/asm-generic/xor.h:688:34: error: ‘xor_block_32regs’ defined but not used [-Werror=unused-variable]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:38 +10:00
Mathieu Malaterre
eae5f709a4 powerpc: Add __printf verification to prom_printf
__printf is useful to verify format and arguments. Fix arg mismatch
reported by gcc, remove the following warnings (with W=1):

  arch/powerpc/kernel/prom_init.c:1467:31: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1471:31: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1504:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1505:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1506:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1507:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1508:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1509:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1975:39: error: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘unsigned int’
  arch/powerpc/kernel/prom_init.c:1986:27: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2567:38: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2567:46: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2569:38: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2569:46: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’

The patch also include arg mismatch fix for case with #define DEBUG_PROM
(warning not listed here).

This patch fix also the following warnings revealed by checkpatch:

  WARNING: Prefer using '"%s...", __func__' to using 'alloc_up', this function's name, in a string
  #101: FILE: arch/powerpc/kernel/prom_init.c:1235:
  + prom_debug("alloc_up(%lx, %lx)\n", size, align);

and

  WARNING: Prefer using '"%s...", __func__' to using 'alloc_down', this function's name, in a string
  #138: FILE: arch/powerpc/kernel/prom_init.c:1278:
  + prom_debug("alloc_down(%lx, %lx, %s)\n", size, align,

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:37 +10:00
Michael Ellerman
2e0986d761 powerpc/xmon: Update paca fields dumped in xmon
The set of paca fields we dump in xmon has gotten somewhat out of
date. Update to add some recently added fields.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:37 +10:00
Michael Ellerman
9ce53e2726 powerpc/xmon: Realign paca dump fields
We've added some fields with longer names since we originally wrote
this, so the fields are no longer lined up. Adjust the widths to make
it all look nice again, eg:

  0:mon> dp
  paca for cpu 0x0 @ c000000001fa0000:
   possible                  = yes
   ...
   slb_shadow            [0] = 0xc000000008000000 0x400ea1b217000500
   slb_shadow            [1] = 0xd000000008000001 0x400d43642f000510
   ...
   rfi_flush_fallback_area   = c0000000fff80000   (0xcc8)
   ...
   accounting.starttime_user = 0x51582f07         (0xae8)

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:36 +10:00
Mathieu Malaterre
e70d8f5526 powerpc/xmon: Add __printf annotation to xmon_printf()
This allows the compiler to verify the format strings vs the types of
the arguments.

Update the other prototype declarations in asm/xmon.h.

Silence warnings (triggered at W=1) by adding relevant __printf
attribute. Move #define at bottom of the file to prevent conflict with
gcc attribute.

Solves the original warning:

  arch/powerpc/xmon/nonstdio.c:178:2: error: function might be
  possible candidate for ‘gnu_printf’ format attribute

In turn this uncovered many formatting errors in xmon.c, all fixed in
this patch.

Signed-off-by: Mathieu Malaterre <malat@debian.org>
[mpe: Always use px not p, fixup the 44x specific code, tweak change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:36 +10:00
Michael Ellerman
6671683db8 powerpc/xmon: Specify the full format in DUMP() macro
In dump_one_paca() the DUMP macro unconditionally prepends '#' to the
printf format specifier. In most cases we're using either 'x' or 'lx'
etc. and that is OK. But for 'p' and other formats using '#' is
actually undefined, and once we enable printf() checking for
xmon_printf() we will get warnings from the compiler.

So just have each usage specify the full format, that way we can omit
'#' when it's inappropriate.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Mathieu Malaterre <malat@debian.org>
2018-05-25 12:04:35 +10:00
Michal Suchanek
7daf593009 powerpc/xmon: Also setup debugger hooks when single-stepping
When single-stepping kernel code from xmon without a debug hook
enabled the kernel crashes. This can happen when kernel starts with
xmon on crash disabled but xmon is entered using sysrq.

Call force_enable_xmon when single-stepping in xmon to install the
xmon debug hooks.

Fixes: e1368d0c9e ("powerpc/xmon: Setup debugger hooks when first break-point is set")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 00:08:26 +10:00
Christophe Leroy
e4ccb1dae6 powerpc/8xx: fix invalid register expression in head_8xx.S
New binutils generate the following warning

  AS      arch/powerpc/kernel/head_8xx.o
arch/powerpc/kernel/head_8xx.S: Assembler messages:
arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression

This patch fixes it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 00:08:26 +10:00
Christophe Leroy
0e36b0d125 powerpc/mm: Only read faulting instruction when necessary in do_page_fault()
Commit a7a9dcd882 ("powerpc: Avoid taking a data miss on every
userspace instruction miss") has shown that limiting the read of
faulting instruction to likely cases improves performance.

This patch goes further into this direction by limiting the read
of the faulting instruction to the only cases where it is likely
needed.

On an MPC885, with the same benchmark app as in the commit referred
above, we see a reduction of about 3900 dTLB misses (approx 3%):

Before the patch:
 Performance counter stats for './fault 500' (10 runs):

         683033312      cpu-cycles                                                    ( +-  0.03% )
            134538      dTLB-load-misses                                              ( +-  0.03% )
             46099      iTLB-load-misses                                              ( +-  0.02% )
             19681      faults                                                        ( +-  0.02% )

       5.389747878 seconds time elapsed                                          ( +-  0.06% )

With the patch:

 Performance counter stats for './fault 500' (10 runs):

         682112862      cpu-cycles                                                    ( +-  0.03% )
            130619      dTLB-load-misses                                              ( +-  0.03% )
             46073      iTLB-load-misses                                              ( +-  0.05% )
             19681      faults                                                        ( +-  0.01% )

       5.381342641 seconds time elapsed                                          ( +-  0.07% )

The proper work of the huge stack expansion was tested with the
following app:

int main(int argc, char **argv)
{
	char buf[1024 * 1025];

	sprintf(buf, "Hello world !\n");
	printf(buf);

	exit(0);
}

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add include of pagemap.h to fix build errors]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 00:08:25 +10:00