From 38e760a1335ffaca5a08624a9aed6fe2055c2c98 Mon Sep 17 00:00:00 2001 From: Joe Korty Date: Wed, 17 Oct 2007 18:04:40 +0200 Subject: [PATCH] x86: expand /proc/interrupts to include missing vectors, v2 Add missing IRQs and IRQ descriptions to /proc/interrupts. /proc/interrupts is most useful when it displays every IRQ vector in use by the system, not just those somebody thought would be interesting. This patch inserts the following vector displays to the i386 and x86_64 platforms, as appropriate: rescheduling interrupts TLB flush interrupts function call interrupts thermal event interrupts threshold interrupts spurious interrupts A threshold interrupt occurs when ECC memory correction is occuring at too high a frequency. Thresholds are used by the ECC hardware as occasional ECC failures are part of normal operation, but long sequences of ECC failures usually indicate a memory chip that is about to fail. Thermal event interrupts occur when a temperature threshold has been exceeded for some CPU chip. IIRC, a thermal interrupt is also generated when the temperature drops back to a normal level. A spurious interrupt is an interrupt that was raised then lowered by the device before it could be fully processed by the APIC. Hence the apic sees the interrupt but does not know what device it came from. For this case the APIC hardware will assume a vector of 0xff. Rescheduling, call, and TLB flush interrupts are sent from one CPU to another per the needs of the OS. Typically, their statistics would be used to discover if an interrupt flood of the given type has been occuring. AK: merged v2 and v4 which had some more tweaks AK: replace Local interrupts with Local timer interrupts AK: Fixed description of interrupt types. [ tglx: arch/x86 adaptation ] [ mingo: small cleanup ] Signed-off-by: Joe Korty Signed-off-by: Andi Kleen Cc: Tim Hockin Cc: Andi Kleen Cc: Ingo Molnar Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- Documentation/filesystems/proc.txt | 30 +++++++++++++++++++++++++++- arch/x86/kernel/apic_32.c | 1 + arch/x86/kernel/apic_64.c | 1 + arch/x86/kernel/cpu/mcheck/p4.c | 1 + arch/x86/kernel/irq_32.c | 31 +++++++++++++++++++++++++++-- arch/x86/kernel/irq_64.c | 30 ++++++++++++++++++++++++++-- arch/x86/kernel/mce_amd_64.c | 1 + arch/x86/kernel/mce_intel_64.c | 1 + arch/x86/kernel/smp_32.c | 3 +++ arch/x86/kernel/smp_64.c | 3 +++ arch/x86/mach-voyager/voyager_smp.c | 1 + arch/x86/xen/smp.c | 1 + include/asm-x86/hardirq_32.h | 5 +++++ include/asm-x86/pda.h | 6 ++++++ 14 files changed, 110 insertions(+), 5 deletions(-) diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 4a37e25e69..e5c1df52a8 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -347,7 +347,35 @@ connects the CPUs in a SMP system. This means that an error has been detected, the IO-APIC automatically retry the transmission, so it should not be a big problem, but you should read the SMP-FAQ. -In this context it could be interesting to note the new irq directory in 2.4. +In 2.6.2* /proc/interrupts was expanded again. This time the goal was for +/proc/interrupts to display every IRQ vector in use by the system, not +just those considered 'most important'. The new vectors are: + + THR -- interrupt raised when a machine check threshold counter + (typically counting ECC corrected errors of memory or cache) exceeds + a configurable threshold. Only available on some systems. + + TRM -- a thermal event interrupt occurs when a temperature threshold + has been exceeded for the CPU. This interrupt may also be generated + when the temperature drops back to normal. + + SPU -- a spurious interrupt is some interrupt that was raised then lowered + by some IO device before it could be fully processed by the APIC. Hence + the APIC sees the interrupt but does not know what device it came from. + For this case the APIC will generate the interrupt with a IRQ vector + of 0xff. This might also be generated by chipset bugs. + + RES, CAL, TLB -- rescheduling, call and TLB flush interrupts are + sent from one CPU to another per the needs of the OS. Typically, + their statistics are used by kernel developers and interested users to + determine the occurance of interrupt of the given type. + +The above IRQ vectors are displayed only when relevent. For example, +the threshold vector does not exist on x86_64 platforms. Others are +suppressed when the system is a uniprocessor. As of this writing, only +i386 and x86_64 platforms support the new IRQ vector displays. + +Of some interest is the introduction of the /proc/irq directory to 2.4. It could be used to set IRQ to CPU affinity, this means that you can "hook" an IRQ to only one CPU, or to exclude a CPU of handling IRQs. The contents of the irq subdir is one subdir for each IRQ, and one file; prof_cpu_mask diff --git a/arch/x86/kernel/apic_32.c b/arch/x86/kernel/apic_32.c index 3d67ae18d7..793341fffc 100644 --- a/arch/x86/kernel/apic_32.c +++ b/arch/x86/kernel/apic_32.c @@ -1277,6 +1277,7 @@ void smp_spurious_interrupt(struct pt_regs *regs) /* see sw-dev-man vol 3, chapter 7.4.13.5 */ printk(KERN_INFO "spurious APIC interrupt on CPU#%d, " "should never happen.\n", smp_processor_id()); + __get_cpu_var(irq_stat).irq_spurious_count++; irq_exit(); } diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c index 2250c654ea..f47bc493db 100644 --- a/arch/x86/kernel/apic_64.c +++ b/arch/x86/kernel/apic_64.c @@ -1140,6 +1140,7 @@ asmlinkage void smp_spurious_interrupt(void) if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f))) ack_APIC_irq(); + add_pda(irq_spurious_count, 1); irq_exit(); } diff --git a/arch/x86/kernel/cpu/mcheck/p4.c b/arch/x86/kernel/cpu/mcheck/p4.c index 1509edfb23..be4dabfee1 100644 --- a/arch/x86/kernel/cpu/mcheck/p4.c +++ b/arch/x86/kernel/cpu/mcheck/p4.c @@ -61,6 +61,7 @@ fastcall void smp_thermal_interrupt(struct pt_regs *regs) { irq_enter(); vendor_thermal_interrupt(regs); + __get_cpu_var(irq_stat).irq_thermal_count++; irq_exit(); } diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c index e173b763f1..10f359021a 100644 --- a/arch/x86/kernel/irq_32.c +++ b/arch/x86/kernel/irq_32.c @@ -280,14 +280,41 @@ skip: seq_printf(p, "NMI: "); for_each_online_cpu(j) seq_printf(p, "%10u ", nmi_count(j)); - seq_putc(p, '\n'); + seq_printf(p, " Non-maskable interrupts\n"); #ifdef CONFIG_X86_LOCAL_APIC seq_printf(p, "LOC: "); for_each_online_cpu(j) seq_printf(p, "%10u ", per_cpu(irq_stat,j).apic_timer_irqs); - seq_putc(p, '\n'); + seq_printf(p, " Local timer interrupts\n"); #endif +#ifdef CONFIG_SMP + seq_printf(p, "RES: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + per_cpu(irq_stat,j).irq_resched_count); + seq_printf(p, " Rescheduling interrupts\n"); + seq_printf(p, "CAL: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + per_cpu(irq_stat,j).irq_call_count); + seq_printf(p, " function call interrupts\n"); + seq_printf(p, "TLB: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + per_cpu(irq_stat,j).irq_tlb_count); + seq_printf(p, " TLB shootdowns\n"); +#endif + seq_printf(p, "TRM: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + per_cpu(irq_stat,j).irq_thermal_count); + seq_printf(p, " Thermal event interrupts\n"); + seq_printf(p, "SPU: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + per_cpu(irq_stat,j).irq_spurious_count); + seq_printf(p, " Spurious interrupts\n"); seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); #if defined(CONFIG_X86_IO_APIC) seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count)); diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 865669efc5..3881189df8 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -86,11 +86,37 @@ skip: seq_printf(p, "NMI: "); for_each_online_cpu(j) seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count); - seq_putc(p, '\n'); + seq_printf(p, " Non-maskable interrupts\n"); seq_printf(p, "LOC: "); for_each_online_cpu(j) seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs); - seq_putc(p, '\n'); + seq_printf(p, " Local timer interrupts\n"); +#ifdef CONFIG_SMP + seq_printf(p, "RES: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda(j)->irq_resched_count); + seq_printf(p, " Rescheduling interrupts\n"); + seq_printf(p, "CAL: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda(j)->irq_call_count); + seq_printf(p, " function call interrupts\n"); + seq_printf(p, "TLB: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda(j)->irq_tlb_count); + seq_printf(p, " TLB shootdowns\n"); +#endif + seq_printf(p, "TRM: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda(j)->irq_thermal_count); + seq_printf(p, " Thermal event interrupts\n"); + seq_printf(p, "THR: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda(j)->irq_threshold_count); + seq_printf(p, " Threshold APIC interrupts\n"); + seq_printf(p, "SPU: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda(j)->irq_spurious_count); + seq_printf(p, " Spurious interrupts\n"); seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); } return 0; diff --git a/arch/x86/kernel/mce_amd_64.c b/arch/x86/kernel/mce_amd_64.c index 805b62b1e0..0d2afd96ac 100644 --- a/arch/x86/kernel/mce_amd_64.c +++ b/arch/x86/kernel/mce_amd_64.c @@ -237,6 +237,7 @@ asmlinkage void mce_threshold_interrupt(void) } } out: + add_pda(irq_threshold_count, 1); irq_exit(); } diff --git a/arch/x86/kernel/mce_intel_64.c b/arch/x86/kernel/mce_intel_64.c index 6551505d8a..c17eaf5dd6 100644 --- a/arch/x86/kernel/mce_intel_64.c +++ b/arch/x86/kernel/mce_intel_64.c @@ -26,6 +26,7 @@ asmlinkage void smp_thermal_interrupt(void) if (therm_throt_process(msr_val & 1)) mce_log_therm_throt_event(smp_processor_id(), msr_val); + add_pda(irq_thermal_count, 1); irq_exit(); } diff --git a/arch/x86/kernel/smp_32.c b/arch/x86/kernel/smp_32.c index eebc6e8257..791d9f8036 100644 --- a/arch/x86/kernel/smp_32.c +++ b/arch/x86/kernel/smp_32.c @@ -342,6 +342,7 @@ fastcall void smp_invalidate_interrupt(struct pt_regs *regs) smp_mb__after_clear_bit(); out: put_cpu_no_resched(); + __get_cpu_var(irq_stat).irq_tlb_count++; } void native_flush_tlb_others(const cpumask_t *cpumaskp, struct mm_struct *mm, @@ -640,6 +641,7 @@ static void native_smp_send_stop(void) fastcall void smp_reschedule_interrupt(struct pt_regs *regs) { ack_APIC_irq(); + __get_cpu_var(irq_stat).irq_resched_count++; } fastcall void smp_call_function_interrupt(struct pt_regs *regs) @@ -660,6 +662,7 @@ fastcall void smp_call_function_interrupt(struct pt_regs *regs) */ irq_enter(); (*func)(info); + __get_cpu_var(irq_stat).irq_call_count++; irq_exit(); if (wait) { diff --git a/arch/x86/kernel/smp_64.c b/arch/x86/kernel/smp_64.c index df4a82812a..5c2964727d 100644 --- a/arch/x86/kernel/smp_64.c +++ b/arch/x86/kernel/smp_64.c @@ -163,6 +163,7 @@ asmlinkage void smp_invalidate_interrupt(struct pt_regs *regs) out: ack_APIC_irq(); cpu_clear(cpu, f->flush_cpumask); + add_pda(irq_tlb_count, 1); } static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm, @@ -493,6 +494,7 @@ void smp_send_stop(void) asmlinkage void smp_reschedule_interrupt(void) { ack_APIC_irq(); + add_pda(irq_resched_count, 1); } asmlinkage void smp_call_function_interrupt(void) @@ -514,6 +516,7 @@ asmlinkage void smp_call_function_interrupt(void) exit_idle(); irq_enter(); (*func)(info); + add_pda(irq_call_count, 1); irq_exit(); if (wait) { mb(); diff --git a/arch/x86/mach-voyager/voyager_smp.c b/arch/x86/mach-voyager/voyager_smp.c index 1f86b529db..e4928aa6bd 100644 --- a/arch/x86/mach-voyager/voyager_smp.c +++ b/arch/x86/mach-voyager/voyager_smp.c @@ -1037,6 +1037,7 @@ smp_call_function_interrupt(void) */ irq_enter(); (*func)(info); + __get_cpu_var(irq_stat).irq_call_count++; irq_exit(); if (wait) { mb(); diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 4fa33c27cc..6c05858545 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -356,6 +356,7 @@ static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id) */ irq_enter(); (*func)(info); + __get_cpu_var(irq_stat).irq_call_count++; irq_exit(); if (wait) { diff --git a/include/asm-x86/hardirq_32.h b/include/asm-x86/hardirq_32.h index 918863530b..4f85f0f4b5 100644 --- a/include/asm-x86/hardirq_32.h +++ b/include/asm-x86/hardirq_32.h @@ -10,6 +10,11 @@ typedef struct { unsigned int __nmi_count; /* arch dependent */ unsigned int apic_timer_irqs; /* arch dependent */ unsigned int irq0_irqs; + unsigned int irq_resched_count; + unsigned int irq_call_count; + unsigned int irq_tlb_count; + unsigned int irq_thermal_count; + unsigned int irq_spurious_count; } ____cacheline_aligned irq_cpustat_t; DECLARE_PER_CPU(irq_cpustat_t, irq_stat); diff --git a/include/asm-x86/pda.h b/include/asm-x86/pda.h index fb49f80eb9..35962bbe5e 100644 --- a/include/asm-x86/pda.h +++ b/include/asm-x86/pda.h @@ -30,6 +30,12 @@ struct x8664_pda { struct mm_struct *active_mm; unsigned apic_timer_irqs; unsigned irq0_irqs; + unsigned irq_resched_count; + unsigned irq_call_count; + unsigned irq_tlb_count; + unsigned irq_thermal_count; + unsigned irq_threshold_count; + unsigned irq_spurious_count; } ____cacheline_aligned_in_smp; extern struct x8664_pda *_cpu_pda[]; -- 2.39.5