linux/arch/powerpc/kernel
Paul Mackerras 56548fc0e8 powerpc/powernv: Return to cpu offline loop when finished in KVM guest
When a secondary hardware thread has finished running a KVM guest, we
currently put that thread into nap mode using a nap instruction in
the KVM code.  This changes the code so that instead of doing a nap
instruction directly, we instead cause the call to power7_nap() that
put the thread into nap mode to return.  The reason for doing this is
to avoid having the KVM code having to know what low-power mode to
put the thread into.

In the case of a secondary thread used to run a KVM guest, the thread
will be offline from the point of view of the host kernel, and the
relevant power7_nap() call is the one in pnv_smp_cpu_disable().
In this case we don't want to clear pending IPIs in the offline loop
in that function, since that might cause us to miss the wakeup for
the next time the thread needs to run a guest.  To tell whether or
not to clear the interrupt, we use the SRR1 value returned from
power7_nap(), and check if it indicates an external interrupt.  We
arrange that the return from power7_nap() when we have finished running
a guest returns 0, so pending interrupts don't get flushed in that
case.

Note that it is important a secondary thread that has finished
executing in the guest, or that didn't have a guest to run, should
not return to power7_nap's caller while the kvm_hstate.hwthread_req
flag in the PACA is non-zero, because the return from power7_nap
will reenable the MMU, and the MMU might still be in guest context.
In this situation we spin at low priority in real mode waiting for
hwthread_req to become zero.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-12-08 13:16:31 +11:00
..
vdso32 powerpc/booke64: Use SPRG7 for VDSO 2014-03-19 19:57:14 -05:00
vdso64 powerpc/booke64: Use SPRG7 for VDSO 2014-03-19 19:57:14 -05:00
.gitignore
align.c powerpc: Remove double braces in alignment code. 2014-11-10 09:59:32 +11:00
asm-offsets.c powerpc/powernv: Cleanup unused MCE definitions/declarations. 2014-12-02 11:03:45 +11:00
audit.c
btext.c
cacheinfo.c powerpc/pseries: Update dynamic cache nodes for suspend/resume operation 2014-03-07 15:54:49 +11:00
cacheinfo.h
compat_audit.c
cpu_setup_6xx.S
cpu_setup_44x.S
cpu_setup_fsl_booke.S powerpc/booke: Restrict SPE exception handlers to e200/e500 cores 2014-09-22 10:11:31 +02:00
cpu_setup_pa6t.S
cpu_setup_power.S powerpc/powernv: Enable POWER8 doorbell IPIs 2014-06-11 17:05:12 +10:00
cpu_setup_ppc970.S
cputable.c powerpc/booke: Restrict SPE exception handlers to e200/e500 cores 2014-09-22 10:11:31 +02:00
crash_dump.c powerpc: Remove superfluous bootmem includes 2014-11-10 09:59:26 +11:00
crash.c arch,powerpc: Convert smp_mb__*() 2014-04-18 14:20:41 +02:00
dbell.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
dma-iommu.c
dma-swiotlb.c powerpc/64: Limit ZONE_DMA32 to 4GiB in swiotlb_detect_4g() 2014-09-03 17:58:22 -05:00
dma.c powerpc: Only do dynamic DMA zone limits on platforms that need it 2014-10-17 09:21:44 +11:00
eeh_cache.c powerpc/eeh: Replace pr_warning() with pr_warn() 2014-08-05 15:41:34 +10:00
eeh_dev.c powerpc/eeh: Replace pr_warning() with pr_warn() 2014-08-05 15:41:34 +10:00
eeh_driver.c powerpc/eeh: Set EEH_PE_RESET on PE reset 2014-12-02 11:03:26 +11:00
eeh_event.c powerpc/powernv: Fix killed EEH event 2014-06-11 17:04:33 +10:00
eeh_pe.c powerpc/eeh: Block PCI config access upon frozen PE 2014-10-15 11:27:20 +11:00
eeh_sysfs.c powerpc/eeh: Show hex prefix for PE state sysfs 2014-10-01 22:23:34 +10:00
eeh.c powerpc: Drop useless warning in eeh_init() 2014-12-02 11:03:45 +11:00
entry_32.S powerpc/ftrace: Fix obsolete comment 2014-11-10 09:59:29 +11:00
entry_64.S powerpc/ftrace: simplify prepare_ftrace_return 2014-11-10 09:59:28 +11:00
epapr_hcalls.S
epapr_paravirt.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2014-06-10 18:54:22 -07:00
exceptions-64e.S powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers 2014-09-22 10:11:31 +02:00
exceptions-64s.S powerpc/powernv: Return to cpu offline loop when finished in KVM guest 2014-12-08 13:16:31 +11:00
fadump.c powerpc/fadump: Fix endianess issues in firmware assisted dump handling 2014-10-30 16:52:46 +11:00
firmware.c
fpu.S powerpc: Don't corrupt transactional state when using FP/VMX in kernel 2014-01-15 13:59:11 +11:00
fsl_booke_entry_mapping.S
ftrace.c powerpc/ftrace: simplify prepare_ftrace_return 2014-11-10 09:59:28 +11:00
head_8xx.S powerpc/8xx: Invalidate non present TLB as early as possible 2014-11-07 18:10:45 -06:00
head_32.S
head_40x.S powerpc: Remove check for CONFIG_SERIAL_TEXT_DEBUG 2014-06-11 16:31:21 +10:00
head_44x.S powerpc/ppc476: Disable BTAC 2014-08-13 15:13:42 +10:00
head_64.S Merge remote-tracking branch 'scott/next' into next 2014-08-05 14:13:41 +10:00
head_booke.h
head_fsl_booke.S powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers 2014-09-22 10:11:31 +02:00
hw_breakpoint.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
ibmebus.c powerpc: make of_device_ids const 2014-09-25 23:14:46 +10:00
idle_6xx.S
idle_book3e.S powerpc: No need to use dot symbols when branching to a function 2014-04-23 10:05:16 +10:00
idle_e500.S
idle_power4.S powerpc: No need to use dot symbols when branching to a function 2014-04-23 10:05:16 +10:00
idle_power7.S powerpc/powernv: Return to cpu offline loop when finished in KVM guest 2014-12-08 13:16:31 +11:00
idle.c
io-workarounds.c
io.c
iomap.c powerpc/kerenl: Enable EEH for IO accessors 2014-06-24 12:43:13 +10:00
iommu.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
irq.c powerpc: Remove superfluous bootmem includes 2014-11-10 09:59:26 +11:00
isa-bridge.c
jump_label.c
kgdb.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
kprobes.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
kvm_emul.S
kvm.c At over 200 commits, covering almost all supported architectures, this 2014-06-04 08:47:12 -07:00
l2cr_6xx.S
legacy_serial.c powerpc: make of_device_ids const 2014-09-25 23:14:46 +10:00
machine_kexec_32.c
machine_kexec_64.c powerpc, kexec: Fix "Processor X is stuck" issue during kexec from ST mode 2014-05-28 13:24:26 +10:00
machine_kexec.c powerpc: Fix endian issues in kexec and crash dump code 2014-02-11 11:24:52 +11:00
Makefile powerpc: Separate ppc32 symbol exports into ppc_ksyms_32.c 2014-09-25 23:14:40 +10:00
mce_power.c powerpc/book3s: Fix partial invalidation of TLBs in MCE code. 2014-12-05 16:26:21 +11:00
mce.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
misc_32.S powerpc: Set the correct ksp_limit on ppc32 when switching to irq stack 2014-02-17 11:19:34 +11:00
misc_64.S powerpc: module: handle MODVERSION for .TOC. 2014-04-23 10:05:28 +10:00
misc.S powerpc: Rename __get_SP() to current_stack_pointer() 2014-10-15 11:23:20 +11:00
module_32.c powerpc: Use pr_fmt in module loader code 2014-10-02 17:33:54 +10:00
module_64.c powerpc: Use pr_fmt in module loader code 2014-10-02 17:33:54 +10:00
module.c
msi.c PCI/MSI/PPC: Remove arch_msi_check_device() 2014-10-01 12:21:14 -06:00
nvram_64.c powerpc: Make a bunch of things static 2014-09-25 23:14:41 +10:00
of_platform.c powerpc: make of_device_ids const 2014-09-25 23:14:46 +10:00
paca.c KVM: PPC: Book3S PR: Rework SLB switching code 2014-05-30 14:26:30 +02:00
pci_32.c powerpc: Remove more traces of bootmem 2014-11-19 21:41:51 +11:00
pci_64.c powerpc: Remove superfluous bootmem includes 2014-11-10 09:59:26 +11:00
pci_dn.c
pci_of_scan.c powerpc: Make a bunch of things static 2014-09-25 23:14:41 +10:00
pci-common.c powerpc: Remove more traces of bootmem 2014-11-19 21:41:51 +11:00
pci-hotplug.c powerpc/PCI: Use pci_is_bridge() to simplify code 2014-05-27 14:57:36 -06:00
pmc.c
ppc32.h
ppc_ksyms_32.c powerpc: Separate ppc32 symbol exports into ppc_ksyms_32.c 2014-09-25 23:14:40 +10:00
ppc_ksyms.c powerpc: Rename __get_SP() to current_stack_pointer() 2014-10-15 11:23:20 +11:00
ppc_save_regs.S
proc_powerpc.c
process.c powerpc: Use generic PIE randomization 2014-11-17 17:55:11 +11:00
prom_init_check.sh powerpc: Simplify symbol check in prom_init_check.sh 2014-09-25 23:14:46 +10:00
prom_init.c powerpc/powernv: Remove OPAL v1 takeover 2014-06-25 13:10:47 +10:00
prom_parse.c
prom.c powerpc: Disable CPU_FTR_TM if TM is disabled by firmware 2014-11-14 17:24:20 +11:00
ptrace32.c
ptrace.c Merge git://git.infradead.org/users/eparis/audit 2014-10-19 16:25:56 -07:00
reloc_32.S
reloc_64.S powerpc: Align p_dyn, p_rela and p_st symbols 2014-03-07 13:50:19 +11:00
rtas_flash.c powerpc: Fix endianness of flash_block_list in rtas_flash 2014-07-28 11:30:54 +10:00
rtas_pci.c powerpc: Remove superfluous bootmem includes 2014-11-10 09:59:26 +11:00
rtas-proc.c powerpc: LLVM complains about forward declaration of struct rtas_sensors 2014-11-10 09:59:32 +11:00
rtas-rtc.c
rtas.c powerpc: Remove some old bootmem related comments 2014-11-10 09:59:25 +11:00
rtasd.c powerpc: Make a bunch of things static 2014-09-25 23:14:41 +10:00
setup_32.c powerpc: Remove unused vgacon_remap_base & fix build break 2014-11-10 09:59:31 +11:00
setup_64.c powerpc: Remove more traces of bootmem 2014-11-19 21:41:51 +11:00
setup-common.c powerpc: Convert power off logic to pm_power_off 2014-11-03 12:12:51 +11:00
signal_32.c powerpc: Use sigsp() 2014-08-06 13:04:32 +02:00
signal_64.c powerpc: Use sigsp() 2014-08-06 13:04:32 +02:00
signal.c powerpc: Use sigsp() 2014-08-06 13:04:32 +02:00
signal.h powerpc: Use get_signal() signal_setup_done() 2014-08-06 13:03:09 +02:00
smp-tbsync.c
smp.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
stacktrace.c powerpc: Rename __get_SP() to current_stack_pointer() 2014-10-15 11:23:20 +11:00
suspend.c nosave: consolidate __nosave_{begin,end} in <asm/sections.h> 2014-10-09 22:26:04 -04:00
swsusp_32.S
swsusp_64.c
swsusp_asm64.S
swsusp_booke.S
swsusp.c
sys_ppc32.c
syscalls.c
sysfs.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
systbl_chk.c
systbl_chk.sh
systbl.S powerpc: Use standard macros for sys_sigpending() & sys_old_getrlimit() 2014-07-28 14:09:23 +10:00
tau_6xx.c
time.c rtc/tpo: Driver to support rtc and wakeup on PowerNV platform 2014-11-17 18:04:01 +11:00
tm.S powerpc: Fix regression of per-CPU DSCR setting 2014-05-28 13:35:40 +10:00
traps.c powerpc: Replace __get_cpu_var uses 2014-11-03 12:12:32 +11:00
udbg_16550.c powerpc: Fix bad NULL pointer check in udbg_uart_getc_poll() 2014-11-12 13:47:20 +11:00
udbg.c powerpc: Remove platforms/wsp and associated pieces 2014-06-11 16:35:38 +10:00
uprobes.c
vdso.c powerpc: Remove superfluous bootmem includes 2014-11-10 09:59:26 +11:00
vecemu.c
vector.S powerpc: Don't corrupt transactional state when using FP/VMX in kernel 2014-01-15 13:59:11 +11:00
vio.c arch/powerpc: replace obsolete strict_strto* calls 2014-08-08 15:57:28 -07:00
vmlinux.lds.S