From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754954Ab1DZM1n (ORCPT ); Tue, 26 Apr 2011 08:27:43 -0400 Received: from mail-ww0-f44.google.com ([74.125.82.44]:52658 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751646Ab1DZM1k (ORCPT ); Tue, 26 Apr 2011 08:27:40 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=bYgqN8/Yovy9i6IZdXEib/lYY6Jw5dnsfAc9BRaLlpX4nL7AvngGAWSe5CC9Ir+N+N IsCDC8IONe4tF8A690Beo6L58N9/xlKB9Gg21jZ/wU3O5Duka11a/eiXAU422YS2Jk5y L6zGXDEFLlKS5RUIHaVq8WCVsNIjVMW9W22Jc= Subject: Re: [BUG] perf and kmemcheck : fatal combination From: Eric Dumazet To: Pekka Enberg Cc: Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Paul Mackerras , Vegard Nossum , linux-kernel , Mathieu Desnoyers In-Reply-To: <1303813668.3358.22.camel@edumazet-laptop> References: <1303747731.2747.182.camel@edumazet-laptop> <1303803525.20212.20.camel@twins> <20110426080443.GA806@elte.hu> <1303808257.3012.3.camel@edumazet-laptop> <1303811635.3358.21.camel@edumazet-laptop> <1303813668.3358.22.camel@edumazet-laptop> Content-Type: text/plain; charset="UTF-8" Date: Tue, 26 Apr 2011 14:27:35 +0200 Message-ID: <1303820855.3358.49.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le mardi 26 avril 2011 à 12:27 +0200, Eric Dumazet a écrit : > Le mardi 26 avril 2011 à 13:08 +0300, Pekka Enberg a écrit : > > > That's just kmemcheck fault handler warning about in_nmi(). You could > > try to make the relevant perf allocations use __GFP_NOTRACK and/or > > SLAB_NOTRACK to avoid page faulting in the perf nmi handler. > > Yes, I am going to try that, thanks > Thats far from trivial, maybe because we dont have NOTRACK api for percpu allocations ? I tried without success following patch diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index 632e5dc..bea4949 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -1632,7 +1632,7 @@ static int validate_event(struct perf_event *event) struct event_constraint *c; int ret = 0; - fake_cpuc = kmalloc(sizeof(*fake_cpuc), GFP_KERNEL | __GFP_ZERO); + fake_cpuc = kmalloc(sizeof(*fake_cpuc), GFP_KERNEL | __GFP_ZERO | ___GFP_NOTRACK); if (!fake_cpuc) return -ENOMEM; @@ -1667,7 +1667,7 @@ static int validate_group(struct perf_event *event) int ret, n; ret = -ENOMEM; - fake_cpuc = kmalloc(sizeof(*fake_cpuc), GFP_KERNEL | __GFP_ZERO); + fake_cpuc = kmalloc(sizeof(*fake_cpuc), GFP_KERNEL | __GFP_ZERO | ___GFP_NOTRACK); if (!fake_cpuc) goto out; diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 43fa20b..a659b61 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1209,7 +1209,7 @@ static int intel_pmu_cpu_prepare(int cpu) return NOTIFY_OK; cpuc->per_core = kzalloc_node(sizeof(struct intel_percore), - GFP_KERNEL, cpu_to_node(cpu)); + GFP_KERNEL | ___GFP_NOTRACK, cpu_to_node(cpu)); if (!cpuc->per_core) return NOTIFY_BAD; diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c index bab491b..e921a2f 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c @@ -84,7 +84,7 @@ static int alloc_pebs_buffer(int cpu) if (!x86_pmu.pebs) return 0; - buffer = kmalloc_node(PEBS_BUFFER_SIZE, GFP_KERNEL | __GFP_ZERO, node); + buffer = kmalloc_node(PEBS_BUFFER_SIZE, GFP_KERNEL | __GFP_ZERO | ___GFP_NOTRACK, node); if (unlikely(!buffer)) return -ENOMEM; @@ -122,7 +122,7 @@ static int alloc_bts_buffer(int cpu) if (!x86_pmu.bts) return 0; - buffer = kmalloc_node(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_ZERO, node); + buffer = kmalloc_node(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_ZERO | ___GFP_NOTRACK, node); if (unlikely(!buffer)) return -ENOMEM; @@ -155,7 +155,7 @@ static int alloc_ds_buffer(int cpu) int node = cpu_to_node(cpu); struct debug_store *ds; - ds = kmalloc_node(sizeof(*ds), GFP_KERNEL | __GFP_ZERO, node); + ds = kmalloc_node(sizeof(*ds), GFP_KERNEL | __GFP_ZERO | ___GFP_NOTRACK, node); if (unlikely(!ds)) return -ENOMEM; diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index ba36217..8c2e3e6 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -211,7 +211,6 @@ extern void irq_exit(void); #define nmi_enter() \ do { \ ftrace_nmi_enter(); \ - BUG_ON(in_nmi()); \ add_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET); \ lockdep_off(); \ rcu_nmi_enter(); \ diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 8e81a98..b09ba81 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -2589,14 +2589,14 @@ static int alloc_callchain_buffers(void) */ size = offsetof(struct callchain_cpus_entries, cpu_entries[nr_cpu_ids]); - entries = kzalloc(size, GFP_KERNEL); + entries = kzalloc(size, GFP_KERNEL | ___GFP_NOTRACK); if (!entries) return -ENOMEM; size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS; for_each_possible_cpu(cpu) { - entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL, + entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL | ___GFP_NOTRACK, cpu_to_node(cpu)); if (!entries->cpu_entries[cpu]) goto fail; @@ -2756,7 +2756,8 @@ alloc_perf_context(struct pmu *pmu, struct task_struct *task) { struct perf_event_context *ctx; - ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); + ctx = kzalloc(sizeof(struct perf_event_context), + GFP_KERNEL | ___GFP_NOTRACK); if (!ctx) return NULL; @@ -3451,7 +3452,7 @@ static void *perf_mmap_alloc_page(int cpu) int node; node = (cpu == -1) ? cpu : cpu_to_node(cpu); - page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0); + page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO | ___GFP_NOTRACK, 0); if (!page) return NULL; @@ -3468,7 +3469,7 @@ perf_buffer_alloc(int nr_pages, long watermark, int cpu, int flags) size = sizeof(struct perf_buffer); size += nr_pages * sizeof(void *); - buffer = kzalloc(size, GFP_KERNEL); + buffer = kzalloc(size, GFP_KERNEL | ___GFP_NOTRACK); if (!buffer) goto fail; @@ -3585,7 +3586,7 @@ perf_buffer_alloc(int nr_pages, long watermark, int cpu, int flags) size = sizeof(struct perf_buffer); size += sizeof(void *); - buffer = kzalloc(size, GFP_KERNEL); + buffer = kzalloc(size, GFP_KERNEL | ___GFP_NOTRACK); if (!buffer) goto fail; @@ -4841,7 +4842,7 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) * need to add enough zero bytes after the string to handle * the 64bit alignment we do later. */ - buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL); + buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL | ___GFP_NOTRACK); if (!buf) { name = strncpy(tmp, "//enomem", sizeof(tmp)); goto got_name; @@ -5385,7 +5386,7 @@ static int swevent_hlist_get_cpu(struct perf_event *event, int cpu) if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { struct swevent_hlist *hlist; - hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); + hlist = kzalloc(sizeof(*hlist), GFP_KERNEL | ___GFP_NOTRACK); if (!hlist) { err = -ENOMEM; goto exit; @@ -5969,7 +5970,7 @@ static int pmu_dev_alloc(struct pmu *pmu) { int ret = -ENOMEM; - pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); + pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL | ___GFP_NOTRACK); if (!pmu->dev) goto out; @@ -6170,7 +6171,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, return ERR_PTR(-EINVAL); } - event = kzalloc(sizeof(*event), GFP_KERNEL); + event = kzalloc(sizeof(*event), GFP_KERNEL | ___GFP_NOTRACK); if (!event) return ERR_PTR(-ENOMEM); @@ -7222,7 +7223,8 @@ static void __cpuinit perf_event_init_cpu(int cpu) if (swhash->hlist_refcount > 0) { struct swevent_hlist *hlist; - hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); + hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL | ___GFP_NOTRACK, + cpu_to_node(cpu)); WARN_ON(!hlist); rcu_assign_pointer(swhash->swevent_hlist, hlist); }