From: Ingo Molnar Date: Thu, 11 Jan 2007 07:15:38 +0000 (-0800) Subject: [PATCH] KVM: add VM-exit profiling X-Git-Tag: v2.6.20-rc5~13 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=07031e14c1127fc7e1a5b98dfcc59f434e025104;p=linux-2.6 [PATCH] KVM: add VM-exit profiling This adds the profile=kvm boot option, which enables KVM to profile VM exits. Use: "readprofile -m ./System.map | sort -n" to see the resulting output: [...] 18246 serial_out 148.3415 18945 native_flush_tlb 378.9000 23618 serial_in 212.7748 29279 __spin_unlock_irq 622.9574 43447 native_apic_write 2068.9048 52702 enable_8259A_irq 742.2817 54250 vgacon_scroll 89.3740 67394 ide_inb 6126.7273 79514 copy_page_range 98.1654 84868 do_wp_page 86.6000 140266 pit_read 783.6089 151436 ide_outb 25239.3333 152668 native_io_delay 21809.7143 174783 mask_and_ack_8259A 783.7803 362404 native_set_pte_at 36240.4000 1688747 total 0.5009 Signed-off-by: Ingo Molnar Acked-by: Avi Kivity Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c index ccc06b1b91..714f6a7841 100644 --- a/drivers/kvm/svm.c +++ b/drivers/kvm/svm.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include "kvm_svm.h" @@ -1558,6 +1559,13 @@ again: reload_tss(vcpu); + /* + * Profile KVM exit RIPs: + */ + if (unlikely(prof_on == KVM_PROFILING)) + profile_hit(KVM_PROFILING, + (void *)(unsigned long)vcpu->svm->vmcb->save.rip); + stgi(); kvm_reput_irq(vcpu); diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index d4701cb4c6..ce219e3f55 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -1859,6 +1860,12 @@ again: asm ("mov %0, %%ds; mov %0, %%es" : : "r"(__USER_DS)); #endif + /* + * Profile KVM exit RIPs: + */ + if (unlikely(prof_on == KVM_PROFILING)) + profile_hit(KVM_PROFILING, (void *)vmcs_readl(GUEST_RIP)); + kvm_run->exit_type = 0; if (fail) { kvm_run->exit_type = KVM_EXIT_TYPE_FAIL_ENTRY; diff --git a/include/linux/profile.h b/include/linux/profile.h index 5670b340c4..eec48f5f93 100644 --- a/include/linux/profile.h +++ b/include/linux/profile.h @@ -15,6 +15,7 @@ extern int prof_on __read_mostly; #define CPU_PROFILING 1 #define SCHED_PROFILING 2 #define SLEEP_PROFILING 3 +#define KVM_PROFILING 4 struct proc_dir_entry; struct pt_regs; diff --git a/kernel/profile.c b/kernel/profile.c index 11550b2290..a6574a1851 100644 --- a/kernel/profile.c +++ b/kernel/profile.c @@ -40,7 +40,10 @@ int (*timer_hook)(struct pt_regs *) __read_mostly; static atomic_t *prof_buffer; static unsigned long prof_len, prof_shift; + int prof_on __read_mostly; +EXPORT_SYMBOL_GPL(prof_on); + static cpumask_t prof_cpu_mask = CPU_MASK_ALL; #ifdef CONFIG_SMP static DEFINE_PER_CPU(struct profile_hit *[2], cpu_profile_hits); @@ -52,6 +55,7 @@ static int __init profile_setup(char * str) { static char __initdata schedstr[] = "schedule"; static char __initdata sleepstr[] = "sleep"; + static char __initdata kvmstr[] = "kvm"; int par; if (!strncmp(str, sleepstr, strlen(sleepstr))) { @@ -72,6 +76,15 @@ static int __init profile_setup(char * str) printk(KERN_INFO "kernel schedule profiling enabled (shift: %ld)\n", prof_shift); + } else if (!strncmp(str, kvmstr, strlen(kvmstr))) { + prof_on = KVM_PROFILING; + if (str[strlen(kvmstr)] == ',') + str += strlen(kvmstr) + 1; + if (get_option(&str, &par)) + prof_shift = par; + printk(KERN_INFO + "kernel KVM profiling enabled (shift: %ld)\n", + prof_shift); } else if (get_option(&str, &par)) { prof_shift = par; prof_on = CPU_PROFILING; @@ -318,6 +331,7 @@ out: local_irq_restore(flags); put_cpu(); } +EXPORT_SYMBOL_GPL(profile_hits); static int __devinit profile_cpu_callback(struct notifier_block *info, unsigned long action, void *__cpu)