From patchwork Wed Nov 18 13:11:47 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 7648701 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E1404BF90C for ; Wed, 18 Nov 2015 13:11:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AE5492046F for ; Wed, 18 Nov 2015 13:11:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62AA7205F4 for ; Wed, 18 Nov 2015 13:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755771AbbKRNLc (ORCPT ); Wed, 18 Nov 2015 08:11:32 -0500 Received: from e06smtp15.uk.ibm.com ([195.75.94.111]:38791 "EHLO e06smtp15.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755661AbbKRNLa (ORCPT ); Wed, 18 Nov 2015 08:11:30 -0500 Received: from localhost by e06smtp15.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 18 Nov 2015 13:11:25 -0000 X-IBM-Helo: d06dlp03.portsmouth.uk.ibm.com X-IBM-MailFrom: borntraeger@de.ibm.com X-IBM-RcptTo: kvm@vger.kernel.org;linux-s390@vger.kernel.org Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 6A4131B0804B; Wed, 18 Nov 2015 13:11:44 +0000 (GMT) Received: from d06av05.portsmouth.uk.ibm.com (d06av05.portsmouth.uk.ibm.com [9.149.37.229]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id tAIDBOAi57147584; Wed, 18 Nov 2015 13:11:24 GMT Received: from d06av05.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av05.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id tAIDBNAp005446; Wed, 18 Nov 2015 06:11:24 -0700 Received: from tuxmaker.boeblingen.de.ibm.com (tuxmaker.boeblingen.de.ibm.com [9.152.85.9]) by d06av05.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id tAIDBNYu005433 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 18 Nov 2015 06:11:23 -0700 Received: by tuxmaker.boeblingen.de.ibm.com (Postfix, from userid 25651) id 7CE7C20F534; Wed, 18 Nov 2015 14:11:23 +0100 (CET) From: Christian Borntraeger To: Paolo Bonzini Cc: KVM , Cornelia Huck , Jens Freimann , Janosch Frank , linux-s390 , Christian Borntraeger Subject: [PATCH 2/2] KVM: Create debugfs dir and stat files for each VM Date: Wed, 18 Nov 2015 14:11:47 +0100 Message-Id: <1447852307-106478-3-git-send-email-borntraeger@de.ibm.com> X-Mailer: git-send-email 2.3.0 In-Reply-To: <1447852307-106478-1-git-send-email-borntraeger@de.ibm.com> References: <1447852307-106478-1-git-send-email-borntraeger@de.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15111813-0021-0000-0000-000007FD3E88 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Janosch Frank KVM statistics for VMs (no. of exits, halts and other special instructions) are currently only available in a summarized manner for all VMs. They are exported to userland through files in the kvm debugfs directory and used for performance monitoring, as well as VM problem detection with helper tools like kvm_stat. If a VM has problems and therefore creates a large number of exits, one can not easily find out which one it is, as there is no VM specific data. This patch adds a kvm debugfs subdirectory for each VM on kvm_create_vm(). The subdirectories are named by the VM pid and contain the same type of exported statistics that are already in the kvm debugfs directory, but the exported data is now VM specific. Signed-off-by: Janosch Frank Reviewed-by: Pierre Morel Acked-by: Christian Borntraeger Signed-off-by: Christian Borntraeger --- include/linux/kvm_host.h | 7 ++ virt/kvm/kvm_main.c | 188 +++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 187 insertions(+), 8 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6981bc6..23071bc 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -425,6 +425,8 @@ struct kvm { #endif long tlbs_dirty; struct list_head devices; + struct dentry *debugfs_dentry; + struct kvm_stat_data **debugfs_data; }; #define kvm_err(fmt, ...) \ @@ -1005,6 +1007,11 @@ enum kvm_stat_kind { KVM_STAT_VCPU, }; +struct kvm_stat_data { + int offset; + struct kvm *kvm; +}; + struct kvm_stats_debugfs_item { const char *name; int offset; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 726bb51..1ee2f73 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -63,6 +63,9 @@ #define CREATE_TRACE_POINTS #include +/* Worst case buffer size needed for holding an integer. */ +#define ITOA_MAX_LEN 12 + MODULE_AUTHOR("Qumranet"); MODULE_LICENSE("GPL"); @@ -100,6 +103,9 @@ static __read_mostly struct preempt_ops kvm_preempt_ops; struct dentry *kvm_debugfs_dir; EXPORT_SYMBOL_GPL(kvm_debugfs_dir); +static u64 kvm_debugfs_num_entries; +static const struct file_operations *stat_fops_per_vm[]; + static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl, unsigned long arg); #ifdef CONFIG_KVM_COMPAT @@ -539,6 +545,71 @@ static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots) kvfree(slots); } +static int kvm_destroy_vm_debugfs(struct kvm *kvm) +{ + u64 i; + struct kvm_stat_data **stat_data = kvm->debugfs_data; + + for (i = 0; i < kvm_debugfs_num_entries; i++) + kfree(stat_data[i]); + + kfree(kvm->debugfs_data); + + return 0; +} + +static int kvm_create_vm_debugfs(struct kvm *kvm) +{ + int r = 0, i = 0; + char dir_name[ITOA_MAX_LEN]; + struct kvm_stat_data *stat_data; + struct kvm_stats_debugfs_item *p; + + if (!kvm) + return -EINVAL; + + snprintf(dir_name, sizeof(dir_name), "%d", current->pid); + kvm->debugfs_dentry = debugfs_create_dir(dir_name, kvm_debugfs_dir); + if (!kvm->debugfs_dentry) + goto out_err; + + kvm->debugfs_data = kmalloc(sizeof(*kvm->debugfs_data) * + kvm_debugfs_num_entries, GFP_KERNEL); + if (!kvm->debugfs_data) + return -ENOMEM; + + for (p = debugfs_entries; p->name; p++, i++) { + stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL); + if (!stat_data) { + r = -ENOMEM; + goto out_err_clean; + } + + stat_data->offset = p->offset; + stat_data->kvm = kvm; + if (!debugfs_create_file(p->name, 0444, + kvm->debugfs_dentry, + stat_data, + stat_fops_per_vm[p->kind])) { + r = -EEXIST; + goto out_err_clean; + } + kvm->debugfs_data[i] = stat_data; + } + + return r; + +out_err_clean: + debugfs_remove_recursive(kvm->debugfs_dentry); + kfree(stat_data); + for (i--; i >= 0; i--) + kfree(kvm->debugfs_data[i]); + + kfree(kvm->debugfs_data); +out_err: + return r; +} + static struct kvm *kvm_create_vm(unsigned long type) { int r, i; @@ -597,6 +668,10 @@ static struct kvm *kvm_create_vm(unsigned long type) list_add(&kvm->vm_list, &vm_list); spin_unlock(&kvm_lock); + r = kvm_create_vm_debugfs(kvm); + if (r) + goto out_err; + preempt_notifier_inc(); return kvm; @@ -646,6 +721,7 @@ static void kvm_destroy_vm(struct kvm *kvm) int i; struct mm_struct *mm = kvm->mm; + kvm_destroy_vm_debugfs(kvm); kvm_arch_sync_events(kvm); spin_lock(&kvm_lock); list_del(&kvm->vm_list); @@ -689,6 +765,7 @@ static int kvm_vm_release(struct inode *inode, struct file *filp) { struct kvm *kvm = filp->private_data; + debugfs_remove_recursive(kvm->debugfs_dentry); kvm_irqfd_release(kvm); kvm_put_kvm(kvm); @@ -3398,15 +3475,107 @@ static struct notifier_block kvm_cpu_notifier = { .notifier_call = kvm_cpu_hotplug, }; +static int kvm_debugfs_open(struct inode *inode, struct file *file, + int (*get)(void *, u64 *), int (*set)(void *, u64), + const char *fmt) +{ + int err; + struct kvm_stat_data *stat_data = (struct kvm_stat_data *) + inode->i_private; + + err = simple_attr_open(inode, file, get, set, fmt); + if (err) + return err; + + kvm_get_kvm(stat_data->kvm); + + return 0; +} + +static int kvm_debugfs_release(struct inode *inode, struct file *file) +{ + struct kvm_stat_data *stat_data = (struct kvm_stat_data *) + inode->i_private; + + simple_attr_release(inode, file); + kvm_put_kvm(stat_data->kvm); + + return 0; +} + +static int vm_stat_get_per_vm(void *data, u64 *val) +{ + struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data; + + *val = *(u32 *)((void *)stat_data->kvm + stat_data->offset); + + return 0; +} + +static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file) +{ + __simple_attr_check_format("%llu\n", 0ull); + return simple_attr_open(inode, file, vm_stat_get_per_vm, + NULL, "%llu\n"); +} + +static const struct file_operations vm_stat_get_per_vm_fops = { + .owner = THIS_MODULE, + .open = vm_stat_get_per_vm_open, + .release = kvm_debugfs_release, + .read = simple_attr_read, + .write = simple_attr_write, + .llseek = generic_file_llseek, +}; + +static int vcpu_stat_get_per_vm(void *data, u64 *val) +{ + int i; + struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data; + struct kvm_vcpu *vcpu; + + *val = 0; + + kvm_for_each_vcpu(i, vcpu, stat_data->kvm) + *val += *(u32 *)((void *)vcpu + stat_data->offset); + + return 0; +} + +static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file) +{ + __simple_attr_check_format("%llu\n", 0ull); + return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm, + NULL, "%llu\n"); +} + +static const struct file_operations vcpu_stat_get_per_vm_fops = { + .owner = THIS_MODULE, + .open = vcpu_stat_get_per_vm_open, + .release = kvm_debugfs_release, + .read = simple_attr_read, + .write = simple_attr_write, + .llseek = generic_file_llseek, +}; + +static const struct file_operations *stat_fops_per_vm[] = { + [KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops, + [KVM_STAT_VM] = &vm_stat_get_per_vm_fops, +}; + static int vm_stat_get(void *_offset, u64 *val) { unsigned offset = (long)_offset; struct kvm *kvm; + struct kvm_stat_data stat_tmp = {.offset = offset}; + u64 tmp_val; *val = 0; spin_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) - *val += *(u32 *)((void *)kvm + offset); + stat_tmp.kvm = kvm; + vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val); + *val += tmp_val; spin_unlock(&kvm_lock); return 0; } @@ -3417,16 +3586,18 @@ static int vcpu_stat_get(void *_offset, u64 *val) { unsigned offset = (long)_offset; struct kvm *kvm; - struct kvm_vcpu *vcpu; - int i; + struct kvm_stat_data stat_tmp = {.offset = offset}; + u64 tmp_val; *val = 0; spin_lock(&kvm_lock); - list_for_each_entry(kvm, &vm_list, vm_list) - kvm_for_each_vcpu(i, vcpu, kvm) - *val += *(u32 *)((void *)vcpu + offset); - + list_for_each_entry(kvm, &vm_list, vm_list) { + stat_tmp.kvm = kvm; + vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val); + *val += tmp_val; + } spin_unlock(&kvm_lock); + return 0; } @@ -3446,7 +3617,8 @@ static int kvm_init_debug(void) if (kvm_debugfs_dir == NULL) goto out; - for (p = debugfs_entries; p->name; ++p) { + kvm_debugfs_num_entries = 0; + for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) { if (!debugfs_create_file(p->name, 0444, kvm_debugfs_dir, (void *)(long)p->offset, stat_fops[p->kind]))