| Message ID | 1384780949-10922-3-git-send-email-vkale@apm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Vinayak, On 2013-11-18 13:22, Vinayak Kale wrote: > Add support for irq registration when pmu interrupt is percpu. > > Signed-off-by: Vinayak Kale <vkale@apm.com> > Signed-off-by: Tuan Phan <tphan@apm.com> > --- > arch/arm64/kernel/perf_event.c | 102 > +++++++++++++++++++++++++++++----------- > 1 file changed, 74 insertions(+), 28 deletions(-) > > diff --git a/arch/arm64/kernel/perf_event.c > b/arch/arm64/kernel/perf_event.c > index cea1594..23475f6 100644 > --- a/arch/arm64/kernel/perf_event.c > +++ b/arch/arm64/kernel/perf_event.c > @@ -22,6 +22,7 @@ > > #include <linux/bitmap.h> > #include <linux/interrupt.h> > +#include <linux/irq.h> > #include <linux/kernel.h> > #include <linux/export.h> > #include <linux/perf_event.h> > @@ -363,22 +364,51 @@ validate_group(struct perf_event *event) > } > > static void > +armpmu_disable_percpu_irq(void *data) > +{ > + struct arm_pmu *armpmu = data; > + struct platform_device *pmu_device = armpmu->plat_device; > + int irq = platform_get_irq(pmu_device, 0); > + > + cpumask_test_and_clear_cpu(smp_processor_id(), > &armpmu->active_irqs); > + disable_percpu_irq(irq); > +} > + > +static void > armpmu_release_hardware(struct arm_pmu *armpmu) > { > int i, irq, irqs; > struct platform_device *pmu_device = armpmu->plat_device; > > - irqs = min(pmu_device->num_resources, num_possible_cpus()); > + irq = platform_get_irq(pmu_device, 0); > > - for (i = 0; i < irqs; ++i) { > - if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) > - continue; > - irq = platform_get_irq(pmu_device, i); > - if (irq >= 0) > - free_irq(irq, armpmu); > + if (irq_to_desc(irq) && irq_is_percpu(irq)) { Why do you need to check the irq_desc here? It really looks like a misuse of the API. Instead, you should check the value of irq itself (it should be strictly positive). > + on_each_cpu(armpmu_disable_percpu_irq, armpmu, 1); > + free_percpu_irq(irq, &cpu_hw_events); > + } else { > + irqs = min(pmu_device->num_resources, num_possible_cpus()); > + > + for (i = 0; i < irqs; ++i) { > + if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) > + continue; > + irq = platform_get_irq(pmu_device, i); > + if (irq >= 0) irq == 0 means "no-irq". You should handle it as an error case. > + free_irq(irq, armpmu); > + } > } > } > > +static void > +armpmu_enable_percpu_irq(void *data) > +{ > + struct arm_pmu *armpmu = data; > + struct platform_device *pmu_device = armpmu->plat_device; > + int irq = platform_get_irq(pmu_device, 0); > + > + enable_percpu_irq(irq, 0); > + cpumask_set_cpu(smp_processor_id(), &armpmu->active_irqs); > +} > + > static int > armpmu_reserve_hardware(struct arm_pmu *armpmu) > { > @@ -396,34 +426,50 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu) > return -ENODEV; > } > > - for (i = 0; i < irqs; ++i) { > - err = 0; > - irq = platform_get_irq(pmu_device, i); > - if (irq < 0) > - continue; > + irq = platform_get_irq(pmu_device, 0); > > - /* > - * If we have a single PMU interrupt that we can't shift, > - * assume that we're running on a uniprocessor machine and > - * continue. Otherwise, continue without this interrupt. > - */ > - if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) { > - pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", > - irq, i); > - continue; > - } > + if (irq_to_desc(irq) && irq_is_percpu(irq)) { Same comment about irq_to_desc. > + err = request_percpu_irq(irq, armpmu->handle_irq, > + "arm-pmu", &cpu_hw_events); > > - err = request_irq(irq, armpmu->handle_irq, > - IRQF_NOBALANCING, > - "arm-pmu", armpmu); > if (err) { > - pr_err("unable to request IRQ%d for ARM PMU counters\n", > - irq); > + pr_err("unable to request percpu IRQ%d for ARM PMU counters\n", > + irq); > armpmu_release_hardware(armpmu); > return err; > } > > - cpumask_set_cpu(i, &armpmu->active_irqs); > + on_each_cpu(armpmu_enable_percpu_irq, armpmu, 1); > + } else { > + for (i = 0; i < irqs; ++i) { > + err = 0; > + irq = platform_get_irq(pmu_device, i); > + if (irq < 0) Same comment about irq == 0. > + continue; > + > + /* > + * If we have a single PMU interrupt that we can't shift, > + * assume that we're running on a uniprocessor machine and > + * continue. Otherwise, continue without this interrupt. > + */ > + if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) { > + pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", > + irq, i); > + continue; > + } > + > + err = request_irq(irq, armpmu->handle_irq, > + IRQF_NOBALANCING, > + "arm-pmu", armpmu); > + if (err) { > + pr_err("unable to request IRQ%d for ARM PMU counters\n", > + irq); > + armpmu_release_hardware(armpmu); > + return err; > + } > + > + cpumask_set_cpu(i, &armpmu->active_irqs); > + } > } > > return 0;
On Mon, Nov 18, 2013 at 7:16 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: > Vinayak, > > > On 2013-11-18 13:22, Vinayak Kale wrote: >> >> Add support for irq registration when pmu interrupt is percpu. >> >> Signed-off-by: Vinayak Kale <vkale@apm.com> >> Signed-off-by: Tuan Phan <tphan@apm.com> >> --- >> arch/arm64/kernel/perf_event.c | 102 >> +++++++++++++++++++++++++++++----------- >> 1 file changed, 74 insertions(+), 28 deletions(-) >> >> diff --git a/arch/arm64/kernel/perf_event.c >> b/arch/arm64/kernel/perf_event.c >> index cea1594..23475f6 100644 >> --- a/arch/arm64/kernel/perf_event.c >> +++ b/arch/arm64/kernel/perf_event.c >> @@ -22,6 +22,7 @@ >> >> #include <linux/bitmap.h> >> #include <linux/interrupt.h> >> +#include <linux/irq.h> >> #include <linux/kernel.h> >> #include <linux/export.h> >> #include <linux/perf_event.h> >> @@ -363,22 +364,51 @@ validate_group(struct perf_event *event) >> } >> >> static void >> +armpmu_disable_percpu_irq(void *data) >> +{ >> + struct arm_pmu *armpmu = data; >> + struct platform_device *pmu_device = armpmu->plat_device; >> + int irq = platform_get_irq(pmu_device, 0); >> + >> + cpumask_test_and_clear_cpu(smp_processor_id(), >> &armpmu->active_irqs); >> + disable_percpu_irq(irq); >> +} >> + >> +static void >> armpmu_release_hardware(struct arm_pmu *armpmu) >> { >> int i, irq, irqs; >> struct platform_device *pmu_device = armpmu->plat_device; >> >> - irqs = min(pmu_device->num_resources, num_possible_cpus()); >> + irq = platform_get_irq(pmu_device, 0); >> >> - for (i = 0; i < irqs; ++i) { >> - if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) >> - continue; >> - irq = platform_get_irq(pmu_device, i); >> - if (irq >= 0) >> - free_irq(irq, armpmu); >> + if (irq_to_desc(irq) && irq_is_percpu(irq)) { > > > Why do you need to check the irq_desc here? It really looks like a misuse of > the API. I don't think it's being misused. In case of invalid irq number, the API would return null. > Instead, you should check the value of irq itself (it should be strictly > positive). > > >> + on_each_cpu(armpmu_disable_percpu_irq, armpmu, 1); >> + free_percpu_irq(irq, &cpu_hw_events); >> + } else { >> + irqs = min(pmu_device->num_resources, >> num_possible_cpus()); >> + >> + for (i = 0; i < irqs; ++i) { >> + if (!cpumask_test_and_clear_cpu(i, >> &armpmu->active_irqs)) >> + continue; >> + irq = platform_get_irq(pmu_device, i); >> + if (irq >= 0) > > > irq == 0 means "no-irq". You should handle it as an error case. This part of the code (for non-percpu irq) was already present in driver as is. Will was Okay with it as per his review on V1 here: http://lists.infradead.org/pipermail/linux-arm-kernel/2013-November/210102.html > > >> + free_irq(irq, armpmu); >> + } >> } >> } >> >> +static void >> +armpmu_enable_percpu_irq(void *data) >> +{ >> + struct arm_pmu *armpmu = data; >> + struct platform_device *pmu_device = armpmu->plat_device; >> + int irq = platform_get_irq(pmu_device, 0); >> + >> + enable_percpu_irq(irq, 0); >> + cpumask_set_cpu(smp_processor_id(), &armpmu->active_irqs); >> +} >> + >> static int >> armpmu_reserve_hardware(struct arm_pmu *armpmu) >> { >> @@ -396,34 +426,50 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu) >> return -ENODEV; >> } >> >> - for (i = 0; i < irqs; ++i) { >> - err = 0; >> - irq = platform_get_irq(pmu_device, i); >> - if (irq < 0) >> - continue; >> + irq = platform_get_irq(pmu_device, 0); >> >> - /* >> - * If we have a single PMU interrupt that we can't shift, >> - * assume that we're running on a uniprocessor machine and >> - * continue. Otherwise, continue without this interrupt. >> - */ >> - if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) { >> - pr_warning("unable to set irq affinity (irq=%d, >> cpu=%u)\n", >> - irq, i); >> - continue; >> - } >> + if (irq_to_desc(irq) && irq_is_percpu(irq)) { > > > Same comment about irq_to_desc. > > >> + err = request_percpu_irq(irq, armpmu->handle_irq, >> + "arm-pmu", &cpu_hw_events); >> >> - err = request_irq(irq, armpmu->handle_irq, >> - IRQF_NOBALANCING, >> - "arm-pmu", armpmu); >> if (err) { >> - pr_err("unable to request IRQ%d for ARM PMU >> counters\n", >> - irq); >> + pr_err("unable to request percpu IRQ%d for ARM PMU >> counters\n", >> + irq); >> armpmu_release_hardware(armpmu); >> return err; >> } >> >> - cpumask_set_cpu(i, &armpmu->active_irqs); >> + on_each_cpu(armpmu_enable_percpu_irq, armpmu, 1); >> + } else { >> + for (i = 0; i < irqs; ++i) { >> + err = 0; >> + irq = platform_get_irq(pmu_device, i); >> + if (irq < 0) > > > Same comment about irq == 0. This part of the code (for non-percpu irq) was already present in driver as is. Will was Okay with it as per his review on V1 here: http://lists.infradead.org/pipermail/linux-arm-kernel/2013-November/210102.html > > >> + continue; >> + >> + /* >> + * If we have a single PMU interrupt that we can't >> shift, >> + * assume that we're running on a uniprocessor >> machine and >> + * continue. Otherwise, continue without this >> interrupt. >> + */ >> + if (irq_set_affinity(irq, cpumask_of(i)) && irqs > >> 1) { >> + pr_warning("unable to set irq affinity >> (irq=%d, cpu=%u)\n", >> + irq, i); >> + continue; >> + } >> + >> + err = request_irq(irq, armpmu->handle_irq, >> + IRQF_NOBALANCING, >> + "arm-pmu", armpmu); >> + if (err) { >> + pr_err("unable to request IRQ%d for ARM >> PMU counters\n", >> + irq); >> + armpmu_release_hardware(armpmu); >> + return err; >> + } >> + >> + cpumask_set_cpu(i, &armpmu->active_irqs); >> + } >> } >> >> return 0; > > > -- > Fast, cheap, reliable. Pick two. > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
On 2013-11-18 14:18, Vinayak Kale wrote: > On Mon, Nov 18, 2013 at 7:16 PM, Marc Zyngier <marc.zyngier@arm.com> > wrote: >> Vinayak, >> >> >> On 2013-11-18 13:22, Vinayak Kale wrote: >>> >>> Add support for irq registration when pmu interrupt is percpu. >>> >>> Signed-off-by: Vinayak Kale <vkale@apm.com> >>> Signed-off-by: Tuan Phan <tphan@apm.com> >>> --- >>> arch/arm64/kernel/perf_event.c | 102 >>> +++++++++++++++++++++++++++++----------- >>> 1 file changed, 74 insertions(+), 28 deletions(-) >>> >>> diff --git a/arch/arm64/kernel/perf_event.c >>> b/arch/arm64/kernel/perf_event.c >>> index cea1594..23475f6 100644 >>> --- a/arch/arm64/kernel/perf_event.c >>> +++ b/arch/arm64/kernel/perf_event.c >>> @@ -22,6 +22,7 @@ >>> >>> #include <linux/bitmap.h> >>> #include <linux/interrupt.h> >>> +#include <linux/irq.h> >>> #include <linux/kernel.h> >>> #include <linux/export.h> >>> #include <linux/perf_event.h> >>> @@ -363,22 +364,51 @@ validate_group(struct perf_event *event) >>> } >>> >>> static void >>> +armpmu_disable_percpu_irq(void *data) >>> +{ >>> + struct arm_pmu *armpmu = data; >>> + struct platform_device *pmu_device = armpmu->plat_device; >>> + int irq = platform_get_irq(pmu_device, 0); >>> + >>> + cpumask_test_and_clear_cpu(smp_processor_id(), >>> &armpmu->active_irqs); >>> + disable_percpu_irq(irq); >>> +} >>> + >>> +static void >>> armpmu_release_hardware(struct arm_pmu *armpmu) >>> { >>> int i, irq, irqs; >>> struct platform_device *pmu_device = armpmu->plat_device; >>> >>> - irqs = min(pmu_device->num_resources, num_possible_cpus()); >>> + irq = platform_get_irq(pmu_device, 0); >>> >>> - for (i = 0; i < irqs; ++i) { >>> - if (!cpumask_test_and_clear_cpu(i, >>> &armpmu->active_irqs)) >>> - continue; >>> - irq = platform_get_irq(pmu_device, i); >>> - if (irq >= 0) >>> - free_irq(irq, armpmu); >>> + if (irq_to_desc(irq) && irq_is_percpu(irq)) { >> >> >> Why do you need to check the irq_desc here? It really looks like a >> misuse of >> the API. > I don't think it's being misused. In case of invalid irq number, the > API would return null. And feeding an error code to irq_to_desc() doesn't disturb you? Do you call that a normal use of the API? Humfff.... M.
On Mon, Nov 18, 2013 at 8:10 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: > On 2013-11-18 14:18, Vinayak Kale wrote: >> >> On Mon, Nov 18, 2013 at 7:16 PM, Marc Zyngier <marc.zyngier@arm.com> >> wrote: >>> >>> Vinayak, >>> >>> >>> On 2013-11-18 13:22, Vinayak Kale wrote: >>>> >>>> >>>> Add support for irq registration when pmu interrupt is percpu. >>>> >>>> Signed-off-by: Vinayak Kale <vkale@apm.com> >>>> Signed-off-by: Tuan Phan <tphan@apm.com> >>>> --- >>>> arch/arm64/kernel/perf_event.c | 102 >>>> +++++++++++++++++++++++++++++----------- >>>> 1 file changed, 74 insertions(+), 28 deletions(-) >>>> >>>> diff --git a/arch/arm64/kernel/perf_event.c >>>> b/arch/arm64/kernel/perf_event.c >>>> index cea1594..23475f6 100644 >>>> --- a/arch/arm64/kernel/perf_event.c >>>> +++ b/arch/arm64/kernel/perf_event.c >>>> @@ -22,6 +22,7 @@ >>>> >>>> #include <linux/bitmap.h> >>>> #include <linux/interrupt.h> >>>> +#include <linux/irq.h> >>>> #include <linux/kernel.h> >>>> #include <linux/export.h> >>>> #include <linux/perf_event.h> >>>> @@ -363,22 +364,51 @@ validate_group(struct perf_event *event) >>>> } >>>> >>>> static void >>>> +armpmu_disable_percpu_irq(void *data) >>>> +{ >>>> + struct arm_pmu *armpmu = data; >>>> + struct platform_device *pmu_device = armpmu->plat_device; >>>> + int irq = platform_get_irq(pmu_device, 0); >>>> + >>>> + cpumask_test_and_clear_cpu(smp_processor_id(), >>>> &armpmu->active_irqs); >>>> + disable_percpu_irq(irq); >>>> +} >>>> + >>>> +static void >>>> armpmu_release_hardware(struct arm_pmu *armpmu) >>>> { >>>> int i, irq, irqs; >>>> struct platform_device *pmu_device = armpmu->plat_device; >>>> >>>> - irqs = min(pmu_device->num_resources, num_possible_cpus()); >>>> + irq = platform_get_irq(pmu_device, 0); >>>> >>>> - for (i = 0; i < irqs; ++i) { >>>> - if (!cpumask_test_and_clear_cpu(i, >>>> &armpmu->active_irqs)) >>>> - continue; >>>> - irq = platform_get_irq(pmu_device, i); >>>> - if (irq >= 0) >>>> - free_irq(irq, armpmu); >>>> + if (irq_to_desc(irq) && irq_is_percpu(irq)) { >>> >>> >>> >>> Why do you need to check the irq_desc here? It really looks like a misuse >>> of >>> the API. >> >> I don't think it's being misused. In case of invalid irq number, the >> API would return null. > > > And feeding an error code to irq_to_desc() doesn't disturb you? Since the API handles the error condition and returns null, so it won't break stuff. But I think your earlier suggestion of checking invalid irq number beforehand is better, since it would help to avoid wasting time in searching the irq desc. > Do you call that a normal use of the API? Humfff.... > > M. > > -- > Fast, cheap, reliable. Pick two. > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index cea1594..23475f6 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -22,6 +22,7 @@ #include <linux/bitmap.h> #include <linux/interrupt.h> +#include <linux/irq.h> #include <linux/kernel.h> #include <linux/export.h> #include <linux/perf_event.h> @@ -363,22 +364,51 @@ validate_group(struct perf_event *event) } static void +armpmu_disable_percpu_irq(void *data) +{ + struct arm_pmu *armpmu = data; + struct platform_device *pmu_device = armpmu->plat_device; + int irq = platform_get_irq(pmu_device, 0); + + cpumask_test_and_clear_cpu(smp_processor_id(), &armpmu->active_irqs); + disable_percpu_irq(irq); +} + +static void armpmu_release_hardware(struct arm_pmu *armpmu) { int i, irq, irqs; struct platform_device *pmu_device = armpmu->plat_device; - irqs = min(pmu_device->num_resources, num_possible_cpus()); + irq = platform_get_irq(pmu_device, 0); - for (i = 0; i < irqs; ++i) { - if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) - continue; - irq = platform_get_irq(pmu_device, i); - if (irq >= 0) - free_irq(irq, armpmu); + if (irq_to_desc(irq) && irq_is_percpu(irq)) { + on_each_cpu(armpmu_disable_percpu_irq, armpmu, 1); + free_percpu_irq(irq, &cpu_hw_events); + } else { + irqs = min(pmu_device->num_resources, num_possible_cpus()); + + for (i = 0; i < irqs; ++i) { + if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) + continue; + irq = platform_get_irq(pmu_device, i); + if (irq >= 0) + free_irq(irq, armpmu); + } } } +static void +armpmu_enable_percpu_irq(void *data) +{ + struct arm_pmu *armpmu = data; + struct platform_device *pmu_device = armpmu->plat_device; + int irq = platform_get_irq(pmu_device, 0); + + enable_percpu_irq(irq, 0); + cpumask_set_cpu(smp_processor_id(), &armpmu->active_irqs); +} + static int armpmu_reserve_hardware(struct arm_pmu *armpmu) { @@ -396,34 +426,50 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu) return -ENODEV; } - for (i = 0; i < irqs; ++i) { - err = 0; - irq = platform_get_irq(pmu_device, i); - if (irq < 0) - continue; + irq = platform_get_irq(pmu_device, 0); - /* - * If we have a single PMU interrupt that we can't shift, - * assume that we're running on a uniprocessor machine and - * continue. Otherwise, continue without this interrupt. - */ - if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) { - pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", - irq, i); - continue; - } + if (irq_to_desc(irq) && irq_is_percpu(irq)) { + err = request_percpu_irq(irq, armpmu->handle_irq, + "arm-pmu", &cpu_hw_events); - err = request_irq(irq, armpmu->handle_irq, - IRQF_NOBALANCING, - "arm-pmu", armpmu); if (err) { - pr_err("unable to request IRQ%d for ARM PMU counters\n", - irq); + pr_err("unable to request percpu IRQ%d for ARM PMU counters\n", + irq); armpmu_release_hardware(armpmu); return err; } - cpumask_set_cpu(i, &armpmu->active_irqs); + on_each_cpu(armpmu_enable_percpu_irq, armpmu, 1); + } else { + for (i = 0; i < irqs; ++i) { + err = 0; + irq = platform_get_irq(pmu_device, i); + if (irq < 0) + continue; + + /* + * If we have a single PMU interrupt that we can't shift, + * assume that we're running on a uniprocessor machine and + * continue. Otherwise, continue without this interrupt. + */ + if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) { + pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", + irq, i); + continue; + } + + err = request_irq(irq, armpmu->handle_irq, + IRQF_NOBALANCING, + "arm-pmu", armpmu); + if (err) { + pr_err("unable to request IRQ%d for ARM PMU counters\n", + irq); + armpmu_release_hardware(armpmu); + return err; + } + + cpumask_set_cpu(i, &armpmu->active_irqs); + } } return 0;