* [PATCH 0/2] LoongArch: KVM: simplify KVM routines
@ 2025-07-16 16:59 Yury Norov
2025-07-16 16:59 ` [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() Yury Norov
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: Yury Norov @ 2025-07-16 16:59 UTC (permalink / raw)
To: Tianrui Zhao, Bibo Mao, Huacai Chen, WANG Xuerui, kvm, loongarch,
linux-kernel
Cc: Yury Norov
From: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Switch KVM functions to use a proper bitmaps API.
Yury Norov (NVIDIA) (2):
LoongArch: KVM: rework kvm_send_pv_ipi()
LoongArch: KVM:: simplify kvm_deliver_intr()
arch/loongarch/kvm/exit.c | 31 ++++++++++++-------------------
arch/loongarch/kvm/interrupt.c | 23 +++--------------------
2 files changed, 15 insertions(+), 39 deletions(-)
--
2.43.0
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() 2025-07-16 16:59 [PATCH 0/2] LoongArch: KVM: simplify KVM routines Yury Norov @ 2025-07-16 16:59 ` Yury Norov 2025-07-18 2:25 ` Bibo Mao 2025-07-16 16:59 ` [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() Yury Norov 2025-07-20 8:50 ` [PATCH 0/2] LoongArch: KVM: simplify KVM routines Huacai Chen 2 siblings, 1 reply; 8+ messages in thread From: Yury Norov @ 2025-07-16 16:59 UTC (permalink / raw) To: Tianrui Zhao, Bibo Mao, Huacai Chen, WANG Xuerui, kvm, loongarch, linux-kernel Cc: Yury Norov From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com> The function in fact traverses a "bitmap" stored in GPR regs A1 and A2, but does it in a non-obvious way by creating a single-word bitmap twice. This patch switches the function to create a single 2-word bitmap, and also employs for_each_set_bit() macro, as it helps to drop most of housekeeping code. While there, convert the function to return void to not confuse readers with unchecked result. Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> --- arch/loongarch/kvm/exit.c | 31 ++++++++++++------------------- 1 file changed, 12 insertions(+), 19 deletions(-) diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index fa52251b3bf1..359afa909cee 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -821,32 +821,25 @@ static int kvm_handle_lbt_disabled(struct kvm_vcpu *vcpu, int ecode) return RESUME_GUEST; } -static int kvm_send_pv_ipi(struct kvm_vcpu *vcpu) +static void kvm_send_pv_ipi(struct kvm_vcpu *vcpu) { - unsigned int min, cpu, i; - unsigned long ipi_bitmap; + DECLARE_BITMAP(ipi_bitmap, BITS_PER_LONG * 2) = { + kvm_read_reg(vcpu, LOONGARCH_GPR_A1), + kvm_read_reg(vcpu, LOONGARCH_GPR_A2) + }; + unsigned int min, cpu; struct kvm_vcpu *dest; min = kvm_read_reg(vcpu, LOONGARCH_GPR_A3); - for (i = 0; i < 2; i++, min += BITS_PER_LONG) { - ipi_bitmap = kvm_read_reg(vcpu, LOONGARCH_GPR_A1 + i); - if (!ipi_bitmap) + for_each_set_bit(cpu, ipi_bitmap, BITS_PER_LONG * 2) { + dest = kvm_get_vcpu_by_cpuid(vcpu->kvm, cpu + min); + if (!dest) continue; - cpu = find_first_bit((void *)&ipi_bitmap, BITS_PER_LONG); - while (cpu < BITS_PER_LONG) { - dest = kvm_get_vcpu_by_cpuid(vcpu->kvm, cpu + min); - cpu = find_next_bit((void *)&ipi_bitmap, BITS_PER_LONG, cpu + 1); - if (!dest) - continue; - - /* Send SWI0 to dest vcpu to emulate IPI interrupt */ - kvm_queue_irq(dest, INT_SWI0); - kvm_vcpu_kick(dest); - } + /* Send SWI0 to dest vcpu to emulate IPI interrupt */ + kvm_queue_irq(dest, INT_SWI0); + kvm_vcpu_kick(dest); } - - return 0; } /* -- 2.43.0 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() 2025-07-16 16:59 ` [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() Yury Norov @ 2025-07-18 2:25 ` Bibo Mao 0 siblings, 0 replies; 8+ messages in thread From: Bibo Mao @ 2025-07-18 2:25 UTC (permalink / raw) To: Yury Norov, Tianrui Zhao, Huacai Chen, WANG Xuerui, kvm, loongarch, linux-kernel On 2025/7/17 上午12:59, Yury Norov wrote: > From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com> > > The function in fact traverses a "bitmap" stored in GPR regs A1 and A2, > but does it in a non-obvious way by creating a single-word bitmap twice. > > This patch switches the function to create a single 2-word bitmap, and > also employs for_each_set_bit() macro, as it helps to drop most of > housekeeping code. > > While there, convert the function to return void to not confuse readers > with unchecked result. > > Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> > --- > arch/loongarch/kvm/exit.c | 31 ++++++++++++------------------- > 1 file changed, 12 insertions(+), 19 deletions(-) > > diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c > index fa52251b3bf1..359afa909cee 100644 > --- a/arch/loongarch/kvm/exit.c > +++ b/arch/loongarch/kvm/exit.c > @@ -821,32 +821,25 @@ static int kvm_handle_lbt_disabled(struct kvm_vcpu *vcpu, int ecode) > return RESUME_GUEST; > } > > -static int kvm_send_pv_ipi(struct kvm_vcpu *vcpu) > +static void kvm_send_pv_ipi(struct kvm_vcpu *vcpu) > { > - unsigned int min, cpu, i; > - unsigned long ipi_bitmap; > + DECLARE_BITMAP(ipi_bitmap, BITS_PER_LONG * 2) = { > + kvm_read_reg(vcpu, LOONGARCH_GPR_A1), > + kvm_read_reg(vcpu, LOONGARCH_GPR_A2) > + }; > + unsigned int min, cpu; > struct kvm_vcpu *dest; > > min = kvm_read_reg(vcpu, LOONGARCH_GPR_A3); > - for (i = 0; i < 2; i++, min += BITS_PER_LONG) { > - ipi_bitmap = kvm_read_reg(vcpu, LOONGARCH_GPR_A1 + i); > - if (!ipi_bitmap) > + for_each_set_bit(cpu, ipi_bitmap, BITS_PER_LONG * 2) { > + dest = kvm_get_vcpu_by_cpuid(vcpu->kvm, cpu + min); > + if (!dest) > continue; > > - cpu = find_first_bit((void *)&ipi_bitmap, BITS_PER_LONG); > - while (cpu < BITS_PER_LONG) { > - dest = kvm_get_vcpu_by_cpuid(vcpu->kvm, cpu + min); > - cpu = find_next_bit((void *)&ipi_bitmap, BITS_PER_LONG, cpu + 1); > - if (!dest) > - continue; > - > - /* Send SWI0 to dest vcpu to emulate IPI interrupt */ > - kvm_queue_irq(dest, INT_SWI0); > - kvm_vcpu_kick(dest); > - } > + /* Send SWI0 to dest vcpu to emulate IPI interrupt */ > + kvm_queue_irq(dest, INT_SWI0); > + kvm_vcpu_kick(dest); > } > - > - return 0; > } > > /* > Reviewed-by: Bibo Mao <maobibo@loongson.cn> ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() 2025-07-16 16:59 [PATCH 0/2] LoongArch: KVM: simplify KVM routines Yury Norov 2025-07-16 16:59 ` [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() Yury Norov @ 2025-07-16 16:59 ` Yury Norov 2025-07-18 2:37 ` Bibo Mao 2025-07-18 4:13 ` Huacai Chen 2025-07-20 8:50 ` [PATCH 0/2] LoongArch: KVM: simplify KVM routines Huacai Chen 2 siblings, 2 replies; 8+ messages in thread From: Yury Norov @ 2025-07-16 16:59 UTC (permalink / raw) To: Tianrui Zhao, Bibo Mao, Huacai Chen, WANG Xuerui, kvm, loongarch, linux-kernel Cc: Yury Norov From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com> The function opencodes for_each_set_bit() macro, which makes it bulky. Using the proper API makes all the housekeeping code going away. Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> --- arch/loongarch/kvm/interrupt.c | 25 ++++--------------------- 1 file changed, 4 insertions(+), 21 deletions(-) diff --git a/arch/loongarch/kvm/interrupt.c b/arch/loongarch/kvm/interrupt.c index 4c3f22de4b40..8462083f0301 100644 --- a/arch/loongarch/kvm/interrupt.c +++ b/arch/loongarch/kvm/interrupt.c @@ -83,28 +83,11 @@ void kvm_deliver_intr(struct kvm_vcpu *vcpu) unsigned long *pending = &vcpu->arch.irq_pending; unsigned long *pending_clr = &vcpu->arch.irq_clear; - if (!(*pending) && !(*pending_clr)) - return; - - if (*pending_clr) { - priority = __ffs(*pending_clr); - while (priority <= INT_IPI) { - kvm_irq_clear(vcpu, priority); - priority = find_next_bit(pending_clr, - BITS_PER_BYTE * sizeof(*pending_clr), - priority + 1); - } - } + for_each_set_bit(priority, pending_clr, INT_IPI + 1) + kvm_irq_clear(vcpu, priority); - if (*pending) { - priority = __ffs(*pending); - while (priority <= INT_IPI) { - kvm_irq_deliver(vcpu, priority); - priority = find_next_bit(pending, - BITS_PER_BYTE * sizeof(*pending), - priority + 1); - } - } + for_each_set_bit(priority, pending, INT_IPI + 1) + kvm_irq_deliver(vcpu, priority); } int kvm_pending_timer(struct kvm_vcpu *vcpu) -- 2.43.0 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() 2025-07-16 16:59 ` [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() Yury Norov @ 2025-07-18 2:37 ` Bibo Mao 2025-07-18 4:13 ` Huacai Chen 1 sibling, 0 replies; 8+ messages in thread From: Bibo Mao @ 2025-07-18 2:37 UTC (permalink / raw) To: Yury Norov, Tianrui Zhao, Huacai Chen, WANG Xuerui, kvm, loongarch, linux-kernel On 2025/7/17 上午12:59, Yury Norov wrote: > From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com> > > The function opencodes for_each_set_bit() macro, which makes it bulky. > Using the proper API makes all the housekeeping code going away. > > Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> > --- > arch/loongarch/kvm/interrupt.c | 25 ++++--------------------- > 1 file changed, 4 insertions(+), 21 deletions(-) > > diff --git a/arch/loongarch/kvm/interrupt.c b/arch/loongarch/kvm/interrupt.c > index 4c3f22de4b40..8462083f0301 100644 > --- a/arch/loongarch/kvm/interrupt.c > +++ b/arch/loongarch/kvm/interrupt.c > @@ -83,28 +83,11 @@ void kvm_deliver_intr(struct kvm_vcpu *vcpu) > unsigned long *pending = &vcpu->arch.irq_pending; > unsigned long *pending_clr = &vcpu->arch.irq_clear; > > - if (!(*pending) && !(*pending_clr)) > - return; > - > - if (*pending_clr) { > - priority = __ffs(*pending_clr); > - while (priority <= INT_IPI) { > - kvm_irq_clear(vcpu, priority); > - priority = find_next_bit(pending_clr, > - BITS_PER_BYTE * sizeof(*pending_clr), > - priority + 1); > - } > - } > + for_each_set_bit(priority, pending_clr, INT_IPI + 1) > + kvm_irq_clear(vcpu, priority); > > - if (*pending) { > - priority = __ffs(*pending); > - while (priority <= INT_IPI) { > - kvm_irq_deliver(vcpu, priority); > - priority = find_next_bit(pending, > - BITS_PER_BYTE * sizeof(*pending), > - priority + 1); > - } > - } > + for_each_set_bit(priority, pending, INT_IPI + 1) > + kvm_irq_deliver(vcpu, priority); > } > > int kvm_pending_timer(struct kvm_vcpu *vcpu) > Hi Yury, Thanks for your patch. And it looks good to me. Reviewed-by: Bibo Mao <maobibo@loongson.cn> Regards Bibo Mao ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() 2025-07-16 16:59 ` [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() Yury Norov 2025-07-18 2:37 ` Bibo Mao @ 2025-07-18 4:13 ` Huacai Chen 2025-07-18 13:24 ` Yury Norov 1 sibling, 1 reply; 8+ messages in thread From: Huacai Chen @ 2025-07-18 4:13 UTC (permalink / raw) To: Yury Norov Cc: Tianrui Zhao, Bibo Mao, WANG Xuerui, kvm, loongarch, linux-kernel Hi, Yury, On Thu, Jul 17, 2025 at 12:59 AM Yury Norov <yury.norov@gmail.com> wrote: > > From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com> > > The function opencodes for_each_set_bit() macro, which makes it bulky. > Using the proper API makes all the housekeeping code going away. > > Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> > --- > arch/loongarch/kvm/interrupt.c | 25 ++++--------------------- > 1 file changed, 4 insertions(+), 21 deletions(-) > > diff --git a/arch/loongarch/kvm/interrupt.c b/arch/loongarch/kvm/interrupt.c > index 4c3f22de4b40..8462083f0301 100644 > --- a/arch/loongarch/kvm/interrupt.c > +++ b/arch/loongarch/kvm/interrupt.c > @@ -83,28 +83,11 @@ void kvm_deliver_intr(struct kvm_vcpu *vcpu) > unsigned long *pending = &vcpu->arch.irq_pending; > unsigned long *pending_clr = &vcpu->arch.irq_clear; > > - if (!(*pending) && !(*pending_clr)) > - return; Is it necessary to keep these two lines? Huacai > - > - if (*pending_clr) { > - priority = __ffs(*pending_clr); > - while (priority <= INT_IPI) { > - kvm_irq_clear(vcpu, priority); > - priority = find_next_bit(pending_clr, > - BITS_PER_BYTE * sizeof(*pending_clr), > - priority + 1); > - } > - } > + for_each_set_bit(priority, pending_clr, INT_IPI + 1) > + kvm_irq_clear(vcpu, priority); > > - if (*pending) { > - priority = __ffs(*pending); > - while (priority <= INT_IPI) { > - kvm_irq_deliver(vcpu, priority); > - priority = find_next_bit(pending, > - BITS_PER_BYTE * sizeof(*pending), > - priority + 1); > - } > - } > + for_each_set_bit(priority, pending, INT_IPI + 1) > + kvm_irq_deliver(vcpu, priority); > } > > int kvm_pending_timer(struct kvm_vcpu *vcpu) > -- > 2.43.0 > > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() 2025-07-18 4:13 ` Huacai Chen @ 2025-07-18 13:24 ` Yury Norov 0 siblings, 0 replies; 8+ messages in thread From: Yury Norov @ 2025-07-18 13:24 UTC (permalink / raw) To: Huacai Chen Cc: Tianrui Zhao, Bibo Mao, WANG Xuerui, kvm, loongarch, linux-kernel On Fri, Jul 18, 2025 at 12:13:46PM +0800, Huacai Chen wrote: > Hi, Yury, > > On Thu, Jul 17, 2025 at 12:59 AM Yury Norov <yury.norov@gmail.com> wrote: > > > > From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com> > > > > The function opencodes for_each_set_bit() macro, which makes it bulky. > > Using the proper API makes all the housekeeping code going away. > > > > Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> > > --- > > arch/loongarch/kvm/interrupt.c | 25 ++++--------------------- > > 1 file changed, 4 insertions(+), 21 deletions(-) > > > > diff --git a/arch/loongarch/kvm/interrupt.c b/arch/loongarch/kvm/interrupt.c > > index 4c3f22de4b40..8462083f0301 100644 > > --- a/arch/loongarch/kvm/interrupt.c > > +++ b/arch/loongarch/kvm/interrupt.c > > @@ -83,28 +83,11 @@ void kvm_deliver_intr(struct kvm_vcpu *vcpu) > > unsigned long *pending = &vcpu->arch.irq_pending; > > unsigned long *pending_clr = &vcpu->arch.irq_clear; > > > > - if (!(*pending) && !(*pending_clr)) > > - return; > Is it necessary to keep these two lines? No. They duplicate the existing logic, and the new one based on for_each_set_bit(). That's why I remove them. Thanks, Yury > > - > > - if (*pending_clr) { > > - priority = __ffs(*pending_clr); > > - while (priority <= INT_IPI) { > > - kvm_irq_clear(vcpu, priority); > > - priority = find_next_bit(pending_clr, > > - BITS_PER_BYTE * sizeof(*pending_clr), > > - priority + 1); > > - } > > - } > > + for_each_set_bit(priority, pending_clr, INT_IPI + 1) > > + kvm_irq_clear(vcpu, priority); > > > > - if (*pending) { > > - priority = __ffs(*pending); > > - while (priority <= INT_IPI) { > > - kvm_irq_deliver(vcpu, priority); > > - priority = find_next_bit(pending, > > - BITS_PER_BYTE * sizeof(*pending), > > - priority + 1); > > - } > > - } > > + for_each_set_bit(priority, pending, INT_IPI + 1) > > + kvm_irq_deliver(vcpu, priority); > > } > > > > int kvm_pending_timer(struct kvm_vcpu *vcpu) > > -- > > 2.43.0 > > > > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 0/2] LoongArch: KVM: simplify KVM routines 2025-07-16 16:59 [PATCH 0/2] LoongArch: KVM: simplify KVM routines Yury Norov 2025-07-16 16:59 ` [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() Yury Norov 2025-07-16 16:59 ` [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() Yury Norov @ 2025-07-20 8:50 ` Huacai Chen 2 siblings, 0 replies; 8+ messages in thread From: Huacai Chen @ 2025-07-20 8:50 UTC (permalink / raw) To: Yury Norov Cc: Tianrui Zhao, Bibo Mao, WANG Xuerui, kvm, loongarch, linux-kernel Applied, thanks. Huacai On Thu, Jul 17, 2025 at 12:59 AM Yury Norov <yury.norov@gmail.com> wrote: > > From: Yury Norov (NVIDIA) <yury.norov@gmail.com> > > Switch KVM functions to use a proper bitmaps API. > > Yury Norov (NVIDIA) (2): > LoongArch: KVM: rework kvm_send_pv_ipi() > LoongArch: KVM:: simplify kvm_deliver_intr() > > arch/loongarch/kvm/exit.c | 31 ++++++++++++------------------- > arch/loongarch/kvm/interrupt.c | 23 +++-------------------- > 2 files changed, 15 insertions(+), 39 deletions(-) > > -- > 2.43.0 > ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2025-07-20 8:51 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2025-07-16 16:59 [PATCH 0/2] LoongArch: KVM: simplify KVM routines Yury Norov 2025-07-16 16:59 ` [PATCH 1/2] LoongArch: KVM: rework kvm_send_pv_ipi() Yury Norov 2025-07-18 2:25 ` Bibo Mao 2025-07-16 16:59 ` [PATCH 2/2] LoongArch: KVM:: simplify kvm_deliver_intr() Yury Norov 2025-07-18 2:37 ` Bibo Mao 2025-07-18 4:13 ` Huacai Chen 2025-07-18 13:24 ` Yury Norov 2025-07-20 8:50 ` [PATCH 0/2] LoongArch: KVM: simplify KVM routines Huacai Chen
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