From patchwork Wed Nov 28 22:01:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathieu Poirier X-Patchwork-Id: 152351 Delivered-To: patch@linaro.org Received: by 2002:a2e:299d:0:0:0:0:0 with SMTP id p29-v6csp1632703ljp; Wed, 28 Nov 2018 14:01:27 -0800 (PST) X-Google-Smtp-Source: AFSGD/UerzLoHBlM15x7WSsKc2Q7HpdxP281HpTIBsJZaTiW/es1XwQHt3YOcHM24DLADie7aiMn X-Received: by 2002:a62:8949:: with SMTP id v70mr4816113pfd.85.1543442487593; Wed, 28 Nov 2018 14:01:27 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1543442487; cv=none; d=google.com; s=arc-20160816; b=frRtJDrLxhQHJcHWU1e6YXCKQDcBPZhJZqeZrAZPk9j5/5uR95kVwDPHaebL5DGaRL xmivZ2Iu71AMZrGoeURxpGdoR3sQO8NEr1CX+8tqKxT428M+shkGugL6k2too+MQ+kcc wn44GjbzWGnRi0T8lkuIiOm1uRzOECjaHp+5RwKyleOdLbjd9EfTJxhFJ7q4syjg7ije O0yYHOGQkh2LySxbknqGIWCPWFkE8jBWnju2aEEK/4utNZ4kZ1qIoZm0JqH2WOF1t7ks 0VZ1mfDfSDmrevyG6KaFuj4+hucagAEVGVH++2u/D0H37HYu/5aL/FOHyPgSI9voR+ui jlBg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature; bh=9ArLK6lkyYJGZT2BBz1S2MAD3wdLFqaTbbWFM/1RhoE=; b=xT1Ql3TjE8W20gz14N6Xivqy/z9BRkVzUHUIOAtkNAz6wwPt5E9EGNE9pp1KYRWHxR bvBgUEyKQ/7IUG1RUG0z8NQ0rlzEbLalmq7m1lxhnI1yAkKevgOiTw1SWHcxPOCqwIU3 q0o4y7Y3ClsNxkEZbOfM6LrUgbAtQrRbTBG2TKDBLQAF5Fidw8osO7sVwQvOak8uk4yJ d30EAyyTMslN2SbI/lA3sg+pT6hRhHi2vKtPnMacjYJoDCpc5pHW8xEjeN953gIAsuWN KvccCDwuQHbq4TNDhSvrqGhDAqA8AR6GLfZ7Fp4qwKOD7zyDLRg8dre3uYzYTm1Fne4L XrMg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=JvaGhXCa; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o127si10155655pfo.251.2018.11.28.14.01.27; Wed, 28 Nov 2018 14:01:27 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=JvaGhXCa; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726623AbeK2JE3 (ORCPT + 32 others); Thu, 29 Nov 2018 04:04:29 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:37079 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726580AbeK2JE2 (ORCPT ); Thu, 29 Nov 2018 04:04:28 -0500 Received: by mail-pg1-f196.google.com with SMTP id 80so10109966pge.4 for ; Wed, 28 Nov 2018 14:01:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=9ArLK6lkyYJGZT2BBz1S2MAD3wdLFqaTbbWFM/1RhoE=; b=JvaGhXCakBbgKtMuu7Am5WMIKyL1OD2YnkifjxC6dd5PMwaDyoS43382toposAuZ7F 7bZkjfvqkB2o70f5BnoJI6GvdJ634Yi8Fc4/P8AXBwzcJbS3j8tj7iZ+iHWsjnoC4he3 roYh+HXd59ZaRQ7y9WJ64ySRMP0dCOyTh3iZs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=9ArLK6lkyYJGZT2BBz1S2MAD3wdLFqaTbbWFM/1RhoE=; b=I9XfabEI6He3j3r+ZyFGzykPMTiryXwMTPoiAuqs0BcbnWmjpHYtRdtTesNckWeS0J 22rKkH/kgpcPN/nqMnhE00d39xSvpVh9skeIhawGpP6pAmFhmibjSUT4YpQKQpmiWEBC 8/r5L3UCvSEyUiyy09t37gS+hLwe6fY4GIBKgo+iLGqVDI3GqlfGMDIe5Uo9eTpCaNhM ZpBEk4vGrsotvSUTTWTNMsg8YuA4mKhu3NJ7j7sD+AvZ3Oq2i4bKg6vNhW7x64Bh/aLs Yx9z5H4PelSDKvVRc4Y/RGDh5DkRwGv+lrdQDlB4eVqXOujTNKtTld1D6MIOnqtkCAyG DLCw== X-Gm-Message-State: AA+aEWZP73KN6eSzxWT7rPDZFlzfk5aJBraIUt0T3LZ1MI0+KabFQpAq Gug0ny/t7vIXJjS6yePdMW9XqA== X-Received: by 2002:a65:41c2:: with SMTP id b2mr34325372pgq.67.1543442483779; Wed, 28 Nov 2018 14:01:23 -0800 (PST) Received: from xps15.cg.shawcable.net (S0106002369de4dac.cg.shawcable.net. [68.147.8.254]) by smtp.gmail.com with ESMTPSA id 12sm8698051pgd.35.2018.11.28.14.01.22 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 28 Nov 2018 14:01:23 -0800 (PST) From: Mathieu Poirier To: acme@kernel.org, peterz@infradead.org, mingo@redhat.com Cc: tglx@linutronix.de, alexander.shishkin@linux.intel.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, will.deacon@arm.com, mark.rutland@arm.com, jolsa@redhat.com, namhyung@kernel.org, adrian.hunter@intel.com, ast@kernel.org, gregkh@linuxfoundation.org, hpa@zytor.com, suzuki.poulosi@arm.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 2/6] perf/core: Use ioctl to communicate driver configuration to kernel Date: Wed, 28 Nov 2018 15:01:14 -0700 Message-Id: <1543442478-31465-3-git-send-email-mathieu.poirier@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1543442478-31465-1-git-send-email-mathieu.poirier@linaro.org> References: <1543442478-31465-1-git-send-email-mathieu.poirier@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds the mechanic needed for user space to send PMU specific configuration to the kernel driver using an ioctl() command. That way events can keep track of options that don't fit in the perf_event_attr structure like the selection of a CoreSight sink to use for the session. Signed-off-by: Mathieu Poirier --- include/linux/perf_event.h | 38 +++++++++++++++++++++++++ kernel/events/core.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 107 insertions(+) -- 2.7.4 diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 53c500f0ca79..629fa1e1d6cf 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -114,6 +114,14 @@ struct hw_perf_event_extra { int idx; /* index in shared_regs->regs[] */ }; +/* + * PMU driver configuration + */ +struct pmu_drv_config { + void *config; + raw_spinlock_t lock; +}; + /** * struct hw_perf_event - performance event hardware details: */ @@ -178,6 +186,9 @@ struct hw_perf_event { /* Last sync'ed generation of filters */ unsigned long addr_filters_gen; + /* PMU driver configuration */ + struct pmu_drv_config drv_config; + /* * hw_perf_event::state flags; used to track the PERF_EF_* state. */ @@ -447,6 +458,17 @@ struct pmu { * Filter events for PMU-specific reasons. */ int (*filter_match) (struct perf_event *event); /* optional */ + + /* + * Validate complex PMU configuration that don't fit in the + * perf_event_attr struct. Returns a PMU specific pointer or an error + * value < 0. + * + * As with addr_filters_validate(), runs in the context of the ioctl() + * process and is not serialized with the rest of the PMU callbacks. + */ + void *(*drv_config_validate) (struct perf_event *event, + char *config_str); }; enum perf_addr_filter_action_t { @@ -1235,6 +1257,11 @@ static inline bool has_addr_filter(struct perf_event *event) return event->pmu->nr_addr_filters; } +static inline bool has_drv_config(struct perf_event *event) +{ + return event->pmu->drv_config_validate; +} + /* * An inherited event uses parent's filters */ @@ -1249,6 +1276,17 @@ perf_event_addr_filters(struct perf_event *event) return ifh; } +static inline struct pmu_drv_config * +perf_event_get_drv_config(struct perf_event *event) +{ + struct pmu_drv_config *cfg = &event->hw.drv_config; + + if (event->parent) + cfg = &event->parent->hw.drv_config; + + return cfg; +} + extern void perf_event_addr_filters_sync(struct perf_event *event); extern int perf_output_begin(struct perf_output_handle *handle, diff --git a/kernel/events/core.c b/kernel/events/core.c index 84530ab358c3..a76c0ce39c4e 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5003,6 +5003,8 @@ static inline int perf_fget_light(int fd, struct fd *p) static int perf_event_set_output(struct perf_event *event, struct perf_event *output_event); static int perf_event_set_filter(struct perf_event *event, void __user *arg); +static int perf_event_set_drv_config(struct perf_event *event, + void __user *arg); static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); static int perf_copy_attr(struct perf_event_attr __user *uattr, struct perf_event_attr *attr); @@ -5089,6 +5091,10 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon return perf_event_modify_attr(event, &new_attr); } + + case PERF_EVENT_IOC_SET_DRV_CONFIG: + return perf_event_set_drv_config(event, (void __user *)arg); + default: return -ENOTTY; } @@ -9128,6 +9134,68 @@ static int perf_event_set_filter(struct perf_event *event, void __user *arg) return ret; } +static void perf_drv_config_replace(struct perf_event *event, void *drv_data) +{ + unsigned long flags; + struct pmu_drv_config *drv_config = &event->hw.drv_config; + + if (!has_drv_config(event)) + return; + + /* Children take their configuration from their parent */ + if (event->parent) + return; + + /* Make sure the PMU doesn't get a handle on the data */ + raw_spin_lock_irqsave(&drv_config->lock, flags); + drv_config->config = drv_data; + raw_spin_unlock_irqrestore(&drv_config->lock, flags); +} + +static int +perf_event_process_drv_config(struct perf_event *event, char *config_str) +{ + int ret = -EINVAL; + void *drv_data; + + /* Make sure ctx.mutex is held */ + lockdep_assert_held(&event->ctx->mutex); + + /* Children take their configuration from their parent */ + if (WARN_ON_ONCE(event->parent)) + goto out; + + drv_data = event->pmu->drv_config_validate(event, config_str); + if (IS_ERR(drv_data)) { + ret = PTR_ERR(drv_data); + goto out; + } + + perf_drv_config_replace(event, drv_data); + + ret = 0; +out: + return ret; +} + +static int perf_event_set_drv_config(struct perf_event *event, void __user *arg) +{ + int ret = -EINVAL; + char *config_str; + + if (!has_drv_config(event)) + return ret; + + config_str = strndup_user(arg, PAGE_SIZE); + if (IS_ERR(config_str)) + return PTR_ERR(config_str); + + ret = perf_event_process_drv_config(event, config_str); + + kfree(config_str); + return ret; +} + /* * hrtimer based swevent callback */ @@ -10052,6 +10120,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, if (attr->freq && attr->sample_freq) hwc->sample_period = 1; hwc->last_period = hwc->sample_period; + raw_spin_lock_init(&hwc->drv_config.lock); local64_set(&hwc->period_left, hwc->sample_period);