From patchwork Wed Jun 12 11:54:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cornelia Huck X-Patchwork-Id: 2709791 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 [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 7704CC1459 for ; Wed, 12 Jun 2013 11:55:37 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D1A412022D for ; Wed, 12 Jun 2013 11:55:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 091D82022F for ; Wed, 12 Jun 2013 11:55:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752380Ab3FLLzR (ORCPT ); Wed, 12 Jun 2013 07:55:17 -0400 Received: from e06smtp12.uk.ibm.com ([195.75.94.108]:58436 "EHLO e06smtp12.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754301Ab3FLLzE (ORCPT ); Wed, 12 Jun 2013 07:55:04 -0400 Received: from /spool/local by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 12 Jun 2013 12:50:26 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (d06relay10.portsmouth.uk.ibm.com [9.149.109.195]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 5EDA01B0806B; Wed, 12 Jun 2013 12:55:01 +0100 (BST) Received: from d06av03.portsmouth.uk.ibm.com (d06av03.portsmouth.uk.ibm.com [9.149.37.213]) by b06cxnps3075.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5CBsoxH51576976; Wed, 12 Jun 2013 11:54:50 GMT Received: from d06av03.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av03.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id r5CBt0WW031836; Wed, 12 Jun 2013 05:55:00 -0600 Received: from tuxmaker.boeblingen.de.ibm.com (tuxmaker.boeblingen.de.ibm.com [9.152.85.9]) by d06av03.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id r5CBsw3E031712; Wed, 12 Jun 2013 05:54:59 -0600 From: Cornelia Huck To: Gleb Natapov , Paolo Bonzini Cc: Christian Borntraeger , Heiko Carstens , Martin Schwidefsky , KVM , linux-s390 , Heinz Graalfs Subject: [PATCH 5/6] KVM: s390, perf: Detect if perf samples belong to KVM host or guest Date: Wed, 12 Jun 2013 13:54:56 +0200 Message-Id: <1371038097-28577-6-git-send-email-cornelia.huck@de.ibm.com> X-Mailer: git-send-email 1.8.1.6 In-Reply-To: <1371038097-28577-1-git-send-email-cornelia.huck@de.ibm.com> References: <1371038097-28577-1-git-send-email-cornelia.huck@de.ibm.com> X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13061211-8372-0000-0000-000006499A6F Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-7.1 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: Heinz Graalfs This patch is based on an original patch of David Hildenbrand. The perf core implementation calls architecture specific code in order to ask for specific information for a particular sample: perf_instruction_pointer() When perf core code asks for the instruction pointer, architecture specific code must detect if a KVM guest was running when the sample was taken. A sample can be associated with a KVM guest when the PSW supervisor state bit is set and the PSW instruction pointer part contains the address of 'sie_exit'. A KVM guest's instruction pointer information is then retrieved via gpsw entry pointed to by the sie control-block. perf_misc_flags() perf code code calls this function in order to associate the kernel vs. user state infomation with a particular sample. Architecture specific code must also first detectif a KVM guest was running at the time the sample was taken. Signed-off-by: Heinz Graalfs Reviewed-by: Hendrik Brueckner Signed-off-by: Christian Borntraeger Signed-off-by: Cornelia Huck --- arch/s390/include/asm/kvm_host.h | 1 + arch/s390/include/asm/perf_event.h | 10 ++++++++ arch/s390/kernel/entry64.S | 1 + arch/s390/kernel/perf_event.c | 52 ++++++++++++++++++++++++++++++++++++++ arch/s390/kernel/s390_ksyms.c | 1 + 5 files changed, 65 insertions(+) diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index d3ffd7e..4339069 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -275,4 +275,5 @@ struct kvm_arch{ }; extern int sie64a(struct kvm_s390_sie_block *, u64 *); +extern char sie_exit; #endif diff --git a/arch/s390/include/asm/perf_event.h b/arch/s390/include/asm/perf_event.h index 5f0173a..1141fb3 100644 --- a/arch/s390/include/asm/perf_event.h +++ b/arch/s390/include/asm/perf_event.h @@ -14,3 +14,13 @@ /* Per-CPU flags for PMU states */ #define PMU_F_RESERVED 0x1000 #define PMU_F_ENABLED 0x2000 + +#ifdef CONFIG_64BIT + +/* Perf callbacks */ +struct pt_regs; +extern unsigned long perf_instruction_pointer(struct pt_regs *regs); +extern unsigned long perf_misc_flags(struct pt_regs *regs); +#define perf_misc_flags(regs) perf_misc_flags(regs) + +#endif /* CONFIG_64BIT */ diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 51d99ac..b094ced 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -964,6 +964,7 @@ sie_done: # See also HANDLE_SIE_INTERCEPT rewind_pad: nop 0 + .globl sie_exit sie_exit: lg %r14,__SF_EMPTY+8(%r15) # load guest register save area stmg %r0,%r13,0(%r14) # save guest gprs 0-13 diff --git a/arch/s390/kernel/perf_event.c b/arch/s390/kernel/perf_event.c index f58f37f..a6fc037 100644 --- a/arch/s390/kernel/perf_event.c +++ b/arch/s390/kernel/perf_event.c @@ -13,6 +13,7 @@ #include #include +#include #include #include #include @@ -39,6 +40,57 @@ int perf_num_counters(void) } EXPORT_SYMBOL(perf_num_counters); +static struct kvm_s390_sie_block *sie_block(struct pt_regs *regs) +{ + struct stack_frame *stack = (struct stack_frame *) regs->gprs[15]; + + if (!stack) + return NULL; + + return (struct kvm_s390_sie_block *) stack->empty1[0]; +} + +static bool is_in_guest(struct pt_regs *regs) +{ + unsigned long ip = instruction_pointer(regs); + + if (user_mode(regs)) + return false; + + return ip == (unsigned long) &sie_exit; +} + +static unsigned long guest_is_user_mode(struct pt_regs *regs) +{ + return sie_block(regs)->gpsw.mask & PSW_MASK_PSTATE; +} + +static unsigned long instruction_pointer_guest(struct pt_regs *regs) +{ + return sie_block(regs)->gpsw.addr & PSW_ADDR_INSN; +} + +unsigned long perf_instruction_pointer(struct pt_regs *regs) +{ + return is_in_guest(regs) ? instruction_pointer_guest(regs) + : instruction_pointer(regs); +} + +static unsigned long perf_misc_guest_flags(struct pt_regs *regs) +{ + return guest_is_user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER + : PERF_RECORD_MISC_GUEST_KERNEL; +} + +unsigned long perf_misc_flags(struct pt_regs *regs) +{ + if (is_in_guest(regs)) + return perf_misc_guest_flags(regs); + + return user_mode(regs) ? PERF_RECORD_MISC_USER + : PERF_RECORD_MISC_KERNEL; +} + void perf_event_print_debug(void) { struct cpumf_ctr_info cf_info; diff --git a/arch/s390/kernel/s390_ksyms.c b/arch/s390/kernel/s390_ksyms.c index 9bdbcef..3bac589 100644 --- a/arch/s390/kernel/s390_ksyms.c +++ b/arch/s390/kernel/s390_ksyms.c @@ -7,6 +7,7 @@ EXPORT_SYMBOL(_mcount); #endif #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE) EXPORT_SYMBOL(sie64a); +EXPORT_SYMBOL(sie_exit); #endif EXPORT_SYMBOL(memcpy); EXPORT_SYMBOL(memset);