| Message ID | 20220608144517.759631860@infradead.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | cpuidle,rcu: Cleanup the mess | expand |
On 6/8/22 4:27 PM, Peter Zijlstra wrote: > vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section > vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section > vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Regards, Srivatsa VMware Photon OS > --- > arch/x86/include/asm/paravirt.h | 6 ++++-- > arch/x86/include/asm/special_insns.h | 4 ++-- > arch/x86/include/asm/xen/hypercall.h | 2 +- > arch/x86/kernel/paravirt.c | 14 ++++++++++++-- > arch/x86/xen/enlighten_pv.c | 2 +- > arch/x86/xen/irq.c | 2 +- > 6 files changed, 21 insertions(+), 9 deletions(-) > > --- a/arch/x86/include/asm/paravirt.h > +++ b/arch/x86/include/asm/paravirt.h > @@ -168,7 +168,7 @@ static inline void __write_cr4(unsigned > PVOP_VCALL1(cpu.write_cr4, x); > } > > -static inline void arch_safe_halt(void) > +static __always_inline void arch_safe_halt(void) > { > PVOP_VCALL0(irq.safe_halt); > } > @@ -178,7 +178,9 @@ static inline void halt(void) > PVOP_VCALL0(irq.halt); > } > > -static inline void wbinvd(void) > +extern noinstr void pv_native_wbinvd(void); > + > +static __always_inline void wbinvd(void) > { > PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV)); > } > --- a/arch/x86/include/asm/special_insns.h > +++ b/arch/x86/include/asm/special_insns.h > @@ -115,7 +115,7 @@ static inline void wrpkru(u32 pkru) > } > #endif > > -static inline void native_wbinvd(void) > +static __always_inline void native_wbinvd(void) > { > asm volatile("wbinvd": : :"memory"); > } > @@ -179,7 +179,7 @@ static inline void __write_cr4(unsigned > native_write_cr4(x); > } > > -static inline void wbinvd(void) > +static __always_inline void wbinvd(void) > { > native_wbinvd(); > } > --- a/arch/x86/include/asm/xen/hypercall.h > +++ b/arch/x86/include/asm/xen/hypercall.h > @@ -382,7 +382,7 @@ MULTI_stack_switch(struct multicall_entr > } > #endif > > -static inline int > +static __always_inline int > HYPERVISOR_sched_op(int cmd, void *arg) > { > return _hypercall2(int, sched_op, cmd, arg); > --- a/arch/x86/kernel/paravirt.c > +++ b/arch/x86/kernel/paravirt.c > @@ -233,6 +233,11 @@ static noinstr void pv_native_set_debugr > native_set_debugreg(regno, val); > } > > +noinstr void pv_native_wbinvd(void) > +{ > + native_wbinvd(); > +} > + > static noinstr void pv_native_irq_enable(void) > { > native_irq_enable(); > @@ -242,6 +247,11 @@ static noinstr void pv_native_irq_disabl > { > native_irq_disable(); > } > + > +static noinstr void pv_native_safe_halt(void) > +{ > + native_safe_halt(); > +} > #endif > > enum paravirt_lazy_mode paravirt_get_lazy_mode(void) > @@ -273,7 +283,7 @@ struct paravirt_patch_template pv_ops = > .cpu.read_cr0 = native_read_cr0, > .cpu.write_cr0 = native_write_cr0, > .cpu.write_cr4 = native_write_cr4, > - .cpu.wbinvd = native_wbinvd, > + .cpu.wbinvd = pv_native_wbinvd, > .cpu.read_msr = native_read_msr, > .cpu.write_msr = native_write_msr, > .cpu.read_msr_safe = native_read_msr_safe, > @@ -307,7 +317,7 @@ struct paravirt_patch_template pv_ops = > .irq.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl), > .irq.irq_disable = __PV_IS_CALLEE_SAVE(pv_native_irq_disable), > .irq.irq_enable = __PV_IS_CALLEE_SAVE(pv_native_irq_enable), > - .irq.safe_halt = native_safe_halt, > + .irq.safe_halt = pv_native_safe_halt, > .irq.halt = native_halt, > #endif /* CONFIG_PARAVIRT_XXL */ > > --- a/arch/x86/xen/enlighten_pv.c > +++ b/arch/x86/xen/enlighten_pv.c > @@ -1019,7 +1019,7 @@ static const typeof(pv_ops) xen_cpu_ops > > .write_cr4 = xen_write_cr4, > > - .wbinvd = native_wbinvd, > + .wbinvd = pv_native_wbinvd, > > .read_msr = xen_read_msr, > .write_msr = xen_write_msr, > --- a/arch/x86/xen/irq.c > +++ b/arch/x86/xen/irq.c > @@ -24,7 +24,7 @@ noinstr void xen_force_evtchn_callback(v > (void)HYPERVISOR_xen_version(0, NULL); > } > > -static void xen_safe_halt(void) > +static noinstr void xen_safe_halt(void) > { > /* Blocking includes an implicit local_irq_enable(). */ > if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0) > >
On Jun 13, 2022, at 11:48 AM, Srivatsa S. Bhat <srivatsa@csail.mit.edu> wrote: > ⚠ External Email > > On 6/8/22 4:27 PM, Peter Zijlstra wrote: >> vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section >> vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section >> vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section >> >> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> > > Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> > >> >> -static inline void wbinvd(void) >> +extern noinstr void pv_native_wbinvd(void); >> + >> +static __always_inline void wbinvd(void) >> { >> PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV)); >> } I guess it is yet another instance of wrong accounting of GCC for the assembly blocks’ weight. I guess it is not a solution for older GCCs, but presumably ____PVOP_ALT_CALL() and friends should have used asm_inline or some new “asm_volatile_inline” variant.
On Mon, Jun 13, 2022 at 07:23:13PM +0000, Nadav Amit wrote: > On Jun 13, 2022, at 11:48 AM, Srivatsa S. Bhat <srivatsa@csail.mit.edu> wrote: > > > ⚠ External Email > > > > On 6/8/22 4:27 PM, Peter Zijlstra wrote: > >> vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section > >> vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section > >> vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section > >> > >> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> > > > > Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> > > > >> > >> -static inline void wbinvd(void) > >> +extern noinstr void pv_native_wbinvd(void); > >> + > >> +static __always_inline void wbinvd(void) > >> { > >> PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV)); > >> } > > I guess it is yet another instance of wrong accounting of GCC for > the assembly blocks’ weight. I guess it is not a solution for older > GCCs, but presumably ____PVOP_ALT_CALL() and friends should have > used asm_inline or some new “asm_volatile_inline” variant. Partially, some of the *SAN options also generate a metric ton of nonsense when enabled and skew the compilers towards not inlining things.
--- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -168,7 +168,7 @@ static inline void __write_cr4(unsigned PVOP_VCALL1(cpu.write_cr4, x); } -static inline void arch_safe_halt(void) +static __always_inline void arch_safe_halt(void) { PVOP_VCALL0(irq.safe_halt); } @@ -178,7 +178,9 @@ static inline void halt(void) PVOP_VCALL0(irq.halt); } -static inline void wbinvd(void) +extern noinstr void pv_native_wbinvd(void); + +static __always_inline void wbinvd(void) { PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV)); } --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -115,7 +115,7 @@ static inline void wrpkru(u32 pkru) } #endif -static inline void native_wbinvd(void) +static __always_inline void native_wbinvd(void) { asm volatile("wbinvd": : :"memory"); } @@ -179,7 +179,7 @@ static inline void __write_cr4(unsigned native_write_cr4(x); } -static inline void wbinvd(void) +static __always_inline void wbinvd(void) { native_wbinvd(); } --- a/arch/x86/include/asm/xen/hypercall.h +++ b/arch/x86/include/asm/xen/hypercall.h @@ -382,7 +382,7 @@ MULTI_stack_switch(struct multicall_entr } #endif -static inline int +static __always_inline int HYPERVISOR_sched_op(int cmd, void *arg) { return _hypercall2(int, sched_op, cmd, arg); --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -233,6 +233,11 @@ static noinstr void pv_native_set_debugr native_set_debugreg(regno, val); } +noinstr void pv_native_wbinvd(void) +{ + native_wbinvd(); +} + static noinstr void pv_native_irq_enable(void) { native_irq_enable(); @@ -242,6 +247,11 @@ static noinstr void pv_native_irq_disabl { native_irq_disable(); } + +static noinstr void pv_native_safe_halt(void) +{ + native_safe_halt(); +} #endif enum paravirt_lazy_mode paravirt_get_lazy_mode(void) @@ -273,7 +283,7 @@ struct paravirt_patch_template pv_ops = .cpu.read_cr0 = native_read_cr0, .cpu.write_cr0 = native_write_cr0, .cpu.write_cr4 = native_write_cr4, - .cpu.wbinvd = native_wbinvd, + .cpu.wbinvd = pv_native_wbinvd, .cpu.read_msr = native_read_msr, .cpu.write_msr = native_write_msr, .cpu.read_msr_safe = native_read_msr_safe, @@ -307,7 +317,7 @@ struct paravirt_patch_template pv_ops = .irq.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl), .irq.irq_disable = __PV_IS_CALLEE_SAVE(pv_native_irq_disable), .irq.irq_enable = __PV_IS_CALLEE_SAVE(pv_native_irq_enable), - .irq.safe_halt = native_safe_halt, + .irq.safe_halt = pv_native_safe_halt, .irq.halt = native_halt, #endif /* CONFIG_PARAVIRT_XXL */ --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -1019,7 +1019,7 @@ static const typeof(pv_ops) xen_cpu_ops .write_cr4 = xen_write_cr4, - .wbinvd = native_wbinvd, + .wbinvd = pv_native_wbinvd, .read_msr = xen_read_msr, .write_msr = xen_write_msr, --- a/arch/x86/xen/irq.c +++ b/arch/x86/xen/irq.c @@ -24,7 +24,7 @@ noinstr void xen_force_evtchn_callback(v (void)HYPERVISOR_xen_version(0, NULL); } -static void xen_safe_halt(void) +static noinstr void xen_safe_halt(void) { /* Blocking includes an implicit local_irq_enable(). */ if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0)
vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> --- arch/x86/include/asm/paravirt.h | 6 ++++-- arch/x86/include/asm/special_insns.h | 4 ++-- arch/x86/include/asm/xen/hypercall.h | 2 +- arch/x86/kernel/paravirt.c | 14 ++++++++++++-- arch/x86/xen/enlighten_pv.c | 2 +- arch/x86/xen/irq.c | 2 +- 6 files changed, 21 insertions(+), 9 deletions(-)