| Message ID | 20210726035036.739609-24-npiggin@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v1,01/55] KVM: PPC: Book3S HV: Remove TM emulation from POWER7/8 path | expand |
Hi Nicholas,
I love your patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v5.14-rc3 next-20210723]
[cannot apply to powerpc/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Nicholas-Piggin/KVM-PPC-Book3S-HV-P9-entry-exit-optimisations/20210726-115329
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ff1176468d368232b684f75e82563369208bc371
config: powerpc-randconfig-r022-20210726 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project c63dbd850182797bc4b76124d08e1c320ab2365d)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install powerpc cross compiling tool for clang build
# apt-get install binutils-powerpc-linux-gnu
# https://github.com/0day-ci/linux/commit/d173e4690cf13578686dbbce48e1f81e925b96af
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Nicholas-Piggin/KVM-PPC-Book3S-HV-P9-entry-exit-optimisations/20210726-115329
git checkout d173e4690cf13578686dbbce48e1f81e925b96af
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
arch/powerpc/kernel/process.c:612:33: error: no member named 'tm_tfhar' in 'struct thread_struct'
current->thread.tm_tfhar = mfspr(SPRN_TFHAR);
~~~~~~~~~~~~~~~ ^
arch/powerpc/kernel/process.c:613:33: error: no member named 'tm_tfiar' in 'struct thread_struct'
current->thread.tm_tfiar = mfspr(SPRN_TFIAR);
~~~~~~~~~~~~~~~ ^
arch/powerpc/kernel/process.c:614:33: error: no member named 'tm_texasr' in 'struct thread_struct'
current->thread.tm_texasr = mfspr(SPRN_TEXASR);
~~~~~~~~~~~~~~~ ^
>> arch/powerpc/kernel/process.c:596:6: warning: no previous prototype for function 'save_user_regs_kvm' [-Wmissing-prototypes]
void save_user_regs_kvm(void)
^
arch/powerpc/kernel/process.c:596:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void save_user_regs_kvm(void)
^
static
>> arch/powerpc/kernel/process.c:611:16: warning: shift count >= width of type [-Wshift-count-overflow]
if (usermsr & MSR_TM) {
^~~~~~
arch/powerpc/include/asm/reg.h:115:17: note: expanded from macro 'MSR_TM'
#define MSR_TM __MASK(MSR_TM_LG) /* Transactional Mem Available */
^~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/reg.h:66:23: note: expanded from macro '__MASK'
#define __MASK(X) (1UL<<(X))
^ ~~~
arch/powerpc/kernel/process.c:615:47: warning: shift count >= width of type [-Wshift-count-overflow]
current->thread.regs->msr &= ~MSR_TM;
^~~~~~
arch/powerpc/include/asm/reg.h:115:17: note: expanded from macro 'MSR_TM'
#define MSR_TM __MASK(MSR_TM_LG) /* Transactional Mem Available */
^~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/reg.h:66:23: note: expanded from macro '__MASK'
#define __MASK(X) (1UL<<(X))
^ ~~~
3 warnings and 3 errors generated.
vim +/save_user_regs_kvm +596 arch/powerpc/kernel/process.c
595
> 596 void save_user_regs_kvm(void)
597 {
598 unsigned long usermsr;
599
600 if (!current->thread.regs)
601 return;
602
603 usermsr = current->thread.regs->msr;
604
605 if (usermsr & MSR_FP)
606 save_fpu(current);
607
608 if (usermsr & MSR_VEC)
609 save_altivec(current);
610
> 611 if (usermsr & MSR_TM) {
612 current->thread.tm_tfhar = mfspr(SPRN_TFHAR);
613 current->thread.tm_tfiar = mfspr(SPRN_TFIAR);
614 current->thread.tm_texasr = mfspr(SPRN_TEXASR);
615 current->thread.regs->msr &= ~MSR_TM;
616 }
617 }
618 EXPORT_SYMBOL_GPL(save_user_regs_kvm);
619
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi Nicholas,
I love your patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.14-rc3 next-20210723]
[cannot apply to powerpc/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Nicholas-Piggin/KVM-PPC-Book3S-HV-P9-entry-exit-optimisations/20210726-115329
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ff1176468d368232b684f75e82563369208bc371
config: powerpc64-randconfig-r024-20210726 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project c63dbd850182797bc4b76124d08e1c320ab2365d)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install powerpc64 cross compiling tool for clang build
# apt-get install binutils-powerpc64-linux-gnu
# https://github.com/0day-ci/linux/commit/d173e4690cf13578686dbbce48e1f81e925b96af
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Nicholas-Piggin/KVM-PPC-Book3S-HV-P9-entry-exit-optimisations/20210726-115329
git checkout d173e4690cf13578686dbbce48e1f81e925b96af
# save the attached .config to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/kernel/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
arch/powerpc/include/asm/io-defs.h:45:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(insw, (unsigned long p, void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:121:1: note: expanded from here
__do_insw
^
arch/powerpc/include/asm/io.h:557:56: note: expanded from macro '__do_insw'
#define __do_insw(p, b, n) readsw((PCI_IO_ADDR)_IO_BASE+(p), (b), (n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/process.c:28:
In file included from include/linux/init_task.h:9:
In file included from include/linux/ftrace.h:10:
In file included from include/linux/trace_recursion.h:5:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:47:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(insl, (unsigned long p, void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:123:1: note: expanded from here
__do_insl
^
arch/powerpc/include/asm/io.h:558:56: note: expanded from macro '__do_insl'
#define __do_insl(p, b, n) readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/process.c:28:
In file included from include/linux/init_task.h:9:
In file included from include/linux/ftrace.h:10:
In file included from include/linux/trace_recursion.h:5:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:49:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(outsb, (unsigned long p, const void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:125:1: note: expanded from here
__do_outsb
^
arch/powerpc/include/asm/io.h:559:58: note: expanded from macro '__do_outsb'
#define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/process.c:28:
In file included from include/linux/init_task.h:9:
In file included from include/linux/ftrace.h:10:
In file included from include/linux/trace_recursion.h:5:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:51:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(outsw, (unsigned long p, const void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:127:1: note: expanded from here
__do_outsw
^
arch/powerpc/include/asm/io.h:560:58: note: expanded from macro '__do_outsw'
#define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/process.c:28:
In file included from include/linux/init_task.h:9:
In file included from include/linux/ftrace.h:10:
In file included from include/linux/trace_recursion.h:5:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:53:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(outsl, (unsigned long p, const void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:129:1: note: expanded from here
__do_outsl
^
arch/powerpc/include/asm/io.h:561:58: note: expanded from macro '__do_outsl'
#define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
~~~~~~~~~~~~~~~~~~~~~^
>> arch/powerpc/kernel/process.c:612:33: error: no member named 'tm_tfhar' in 'struct thread_struct'
current->thread.tm_tfhar = mfspr(SPRN_TFHAR);
~~~~~~~~~~~~~~~ ^
>> arch/powerpc/kernel/process.c:613:33: error: no member named 'tm_tfiar' in 'struct thread_struct'
current->thread.tm_tfiar = mfspr(SPRN_TFIAR);
~~~~~~~~~~~~~~~ ^
>> arch/powerpc/kernel/process.c:614:33: error: no member named 'tm_texasr' in 'struct thread_struct'
current->thread.tm_texasr = mfspr(SPRN_TEXASR);
~~~~~~~~~~~~~~~ ^
>> arch/powerpc/kernel/process.c:596:6: error: no previous prototype for function 'save_user_regs_kvm' [-Werror,-Wmissing-prototypes]
void save_user_regs_kvm(void)
^
arch/powerpc/kernel/process.c:596:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void save_user_regs_kvm(void)
^
static
16 errors generated.
vim +612 arch/powerpc/kernel/process.c
595
> 596 void save_user_regs_kvm(void)
597 {
598 unsigned long usermsr;
599
600 if (!current->thread.regs)
601 return;
602
603 usermsr = current->thread.regs->msr;
604
605 if (usermsr & MSR_FP)
606 save_fpu(current);
607
608 if (usermsr & MSR_VEC)
609 save_altivec(current);
610
611 if (usermsr & MSR_TM) {
> 612 current->thread.tm_tfhar = mfspr(SPRN_TFHAR);
> 613 current->thread.tm_tfiar = mfspr(SPRN_TFIAR);
> 614 current->thread.tm_texasr = mfspr(SPRN_TEXASR);
615 current->thread.regs->msr &= ~MSR_TM;
616 }
617 }
618 EXPORT_SYMBOL_GPL(save_user_regs_kvm);
619
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 185beb290580..00b55b38a460 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -593,6 +593,30 @@ static void save_all(struct task_struct *tsk) msr_check_and_clear(msr_all_available); } +void save_user_regs_kvm(void) +{ + unsigned long usermsr; + + if (!current->thread.regs) + return; + + usermsr = current->thread.regs->msr; + + if (usermsr & MSR_FP) + save_fpu(current); + + if (usermsr & MSR_VEC) + save_altivec(current); + + if (usermsr & MSR_TM) { + current->thread.tm_tfhar = mfspr(SPRN_TFHAR); + current->thread.tm_tfiar = mfspr(SPRN_TFIAR); + current->thread.tm_texasr = mfspr(SPRN_TEXASR); + current->thread.regs->msr &= ~MSR_TM; + } +} +EXPORT_SYMBOL_GPL(save_user_regs_kvm); + void flush_all_to_thread(struct task_struct *tsk) { if (tsk->thread.regs) { diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 2e966d62a583..dedcf3ddba3b 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -4103,6 +4103,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit, struct p9_host_os_sprs host_os_sprs; s64 dec; u64 tb, next_timer; + unsigned long msr; int trap; WARN_ON_ONCE(vcpu->arch.ceded); @@ -4114,8 +4115,23 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit, if (next_timer < time_limit) time_limit = next_timer; + vcpu->arch.ceded = 0; + save_p9_host_os_sprs(&host_os_sprs); + /* MSR bits may have been cleared by context switch */ + msr = 0; + if (IS_ENABLED(CONFIG_PPC_FPU)) + msr |= MSR_FP; + if (cpu_has_feature(CPU_FTR_ALTIVEC)) + msr |= MSR_VEC; + if (cpu_has_feature(CPU_FTR_VSX)) + msr |= MSR_VSX; + if (cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) + msr |= MSR_TM; + msr = msr_check_and_set(msr); + kvmppc_subcore_enter_guest(); vc->entry_exit_map = 1; @@ -4124,12 +4140,13 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit, vcpu_vpa_increment_dispatch(vcpu); if (cpu_has_feature(CPU_FTR_TM) || - cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) { kvmppc_restore_tm_hv(vcpu, vcpu->arch.shregs.msr, true); + msr = mfmsr(); /* TM restore can update msr */ + } switch_pmu_to_guest(vcpu, &host_os_sprs); - msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX); load_fp_state(&vcpu->arch.fp); #ifdef CONFIG_ALTIVEC load_vr_state(&vcpu->arch.vr); @@ -4238,7 +4255,6 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit, restore_p9_host_os_sprs(vcpu, &host_os_sprs); - msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX); store_fp_state(&vcpu->arch.fp); #ifdef CONFIG_ALTIVEC store_vr_state(&vcpu->arch.vr); @@ -4767,6 +4783,8 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit, goto done; } +void save_user_regs_kvm(void); + static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu) { struct kvm_run *run = vcpu->run; @@ -4776,19 +4794,24 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu) unsigned long user_tar = 0; unsigned int user_vrsave; struct kvm *kvm; + unsigned long msr; if (!vcpu->arch.sane) { run->exit_reason = KVM_EXIT_INTERNAL_ERROR; return -EINVAL; } + /* No need to go into the guest when all we'll do is come back out */ + if (signal_pending(current)) { + run->exit_reason = KVM_EXIT_INTR; + return -EINTR; + } + +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM /* * Don't allow entry with a suspended transaction, because * the guest entry/exit code will lose it. - * If the guest has TM enabled, save away their TM-related SPRs - * (they will get restored by the TM unavailable interrupt). */ -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM if (cpu_has_feature(CPU_FTR_TM) && current->thread.regs && (current->thread.regs->msr & MSR_TM)) { if (MSR_TM_ACTIVE(current->thread.regs->msr)) { @@ -4796,12 +4819,6 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu) run->fail_entry.hardware_entry_failure_reason = 0; return -EINVAL; } - /* Enable TM so we can read the TM SPRs */ - mtmsr(mfmsr() | MSR_TM); - current->thread.tm_tfhar = mfspr(SPRN_TFHAR); - current->thread.tm_tfiar = mfspr(SPRN_TFIAR); - current->thread.tm_texasr = mfspr(SPRN_TEXASR); - current->thread.regs->msr &= ~MSR_TM; } #endif @@ -4816,18 +4833,24 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu) kvmppc_core_prepare_to_enter(vcpu); - /* No need to go into the guest when all we'll do is come back out */ - if (signal_pending(current)) { - run->exit_reason = KVM_EXIT_INTR; - return -EINTR; - } - kvm = vcpu->kvm; atomic_inc(&kvm->arch.vcpus_running); /* Order vcpus_running vs. mmu_ready, see kvmppc_alloc_reset_hpt */ smp_mb(); - flush_all_to_thread(current); + msr = 0; + if (IS_ENABLED(CONFIG_PPC_FPU)) + msr |= MSR_FP; + if (cpu_has_feature(CPU_FTR_ALTIVEC)) + msr |= MSR_VEC; + if (cpu_has_feature(CPU_FTR_VSX)) + msr |= MSR_VSX; + if (cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) + msr |= MSR_TM; + msr = msr_check_and_set(msr); + + save_user_regs_kvm(); /* Save userspace EBB and other register values */ if (cpu_has_feature(CPU_FTR_ARCH_207S)) { diff --git a/arch/powerpc/kvm/book3s_hv_p9_entry.c b/arch/powerpc/kvm/book3s_hv_p9_entry.c index a7f63082b4e3..fb9cb34445ea 100644 --- a/arch/powerpc/kvm/book3s_hv_p9_entry.c +++ b/arch/powerpc/kvm/book3s_hv_p9_entry.c @@ -224,6 +224,7 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc vc->tb_offset_applied = vc->tb_offset; } + /* Could avoid mfmsr by passing around, but probably no big deal */ msr = mfmsr(); host_hfscr = mfspr(SPRN_HFSCR);
This reduces the number of mtmsrd required to enable facility bits when saving/restoring registers, by having the KVM code set all bits up front rather than using individual facility functions that set their particular MSR bits. -42 cycles (7803) POWER9 virt-mode NULL hcall Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/kernel/process.c | 24 +++++++++++ arch/powerpc/kvm/book3s_hv.c | 61 ++++++++++++++++++--------- arch/powerpc/kvm/book3s_hv_p9_entry.c | 1 + 3 files changed, 67 insertions(+), 19 deletions(-)