From patchwork Thu Jan 23 11:58:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 11347503 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2962D14B4 for ; Thu, 23 Jan 2020 12:00:07 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8D97D20704 for ; Thu, 23 Jan 2020 12:00:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="DGghBktD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8D97D20704 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=WRDYAqJCz3RT8XOJdex7D2d+VgNswRhwPpjXEUlZTgw=; b=DGghBktDpTPfmK X0rFKKKEoxTNwpB17Zos4xhNT+WJB91Vy5EC1qA9oNR7lFO3N4YlnCpU0ZqTb3DEPEMTXoGek74vj rMjdkmZgXgFn8YiuA9/3yw6kF1MIk9GfyKVMyEGBqfiAEwsVA3OsgSgtqahI8Z6XQOW/HS6AxtH0O VEC6gZ0noY7SdXJviItW1hLTYvaixsuJJ6NbUjJQh7xkCKrhITFkf6olgqGyMYH91yXoq05g69Alu FVr13QbfvQxBX4/j04+ti0bm38Kyb0Jsq6fbX45hNdz2t04fN5Xbdv1dv7exmc5pMRI7Qbx1m4KdH kxveU9Kkb9PWtOInl0CA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iub9U-00011y-Cy; Thu, 23 Jan 2020 12:00:00 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iub8f-0000PV-Dw for linux-arm-kernel@lists.infradead.org; Thu, 23 Jan 2020 11:59:11 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1CF5B328; Thu, 23 Jan 2020 03:59:09 -0800 (PST) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.20]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A365A3F6C4; Thu, 23 Jan 2020 03:59:06 -0800 (PST) From: Andrew Murray To: Catalin Marinas , Will Deacon , Marc Zyngier , Mark Rutland Subject: [PATCH v4 3/3] arm64: perf: Add support for ARMv8.5-PMU 64-bit counters Date: Thu, 23 Jan 2020 11:58:52 +0000 Message-Id: <20200123115852.55595-4-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200123115852.55595-1-andrew.murray@arm.com> References: <20200123115852.55595-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200123_035909_603623_A4E9BA8C X-CRM114-Status: GOOD ( 21.10 ) X-Spam-Score: -0.7 (/) X-Spam-Report: SpamAssassin version 3.4.3 on bombadil.infradead.org summary: Content analysis details: (-0.7 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at https://www.dnswl.org/, low trust [217.140.110.172 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org At present ARMv8 event counters are limited to 32-bits, though by using the CHAIN event it's possible to combine adjacent counters to achieve 64-bits. The perf config1:0 bit can be set to use such a configuration. With the introduction of ARMv8.5-PMU support, all event counters can now be used as 64-bit counters. Let's enable 64-bit event counters where support exists. Unless the user sets config1:0 we will adjust the counter value such that it overflows upon 32-bit overflow. This follows the same behaviour as the cycle counter which has always been (and remains) 64-bits. Signed-off-by: Andrew Murray Reviewed-by: Suzuki K Poulose --- arch/arm64/include/asm/perf_event.h | 3 +- arch/arm64/kernel/perf_event.c | 86 +++++++++++++++++++++++------ include/linux/perf/arm_pmu.h | 1 + 3 files changed, 72 insertions(+), 18 deletions(-) diff --git a/arch/arm64/include/asm/perf_event.h b/arch/arm64/include/asm/perf_event.h index 2bdbc79bbd01..e7765b62c712 100644 --- a/arch/arm64/include/asm/perf_event.h +++ b/arch/arm64/include/asm/perf_event.h @@ -176,9 +176,10 @@ #define ARMV8_PMU_PMCR_X (1 << 4) /* Export to ETM */ #define ARMV8_PMU_PMCR_DP (1 << 5) /* Disable CCNT if non-invasive debug*/ #define ARMV8_PMU_PMCR_LC (1 << 6) /* Overflow on 64 bit cycle counter */ +#define ARMV8_PMU_PMCR_LP (1 << 7) /* Long event counter enable */ #define ARMV8_PMU_PMCR_N_SHIFT 11 /* Number of counters supported */ #define ARMV8_PMU_PMCR_N_MASK 0x1f -#define ARMV8_PMU_PMCR_MASK 0x7f /* Mask for writable bits */ +#define ARMV8_PMU_PMCR_MASK 0xff /* Mask for writable bits */ /* * PMOVSR: counters overflow flag status reg diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index e40b65645c86..4e27f90bb89e 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -285,6 +285,17 @@ static struct attribute_group armv8_pmuv3_format_attr_group = { #define ARMV8_IDX_COUNTER_LAST(cpu_pmu) \ (ARMV8_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1) + +/* + * We unconditionally enable ARMv8.5-PMU long event counter support + * (64-bit events) where supported. Indicate if this arm_pmu has long + * event counter support. + */ +static bool armv8pmu_has_long_event(struct arm_pmu *cpu_pmu) +{ + return (cpu_pmu->pmuver > ID_DFR0_EL1_PMUVER_8_4); +} + /* * We must chain two programmable counters for 64 bit events, * except when we have allocated the 64bit cycle counter (for CPU @@ -294,9 +305,11 @@ static struct attribute_group armv8_pmuv3_format_attr_group = { static inline bool armv8pmu_event_is_chained(struct perf_event *event) { int idx = event->hw.idx; + struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu); return !WARN_ON(idx < 0) && armv8pmu_event_is_64bit(event) && + !armv8pmu_has_long_event(cpu_pmu) && (idx != ARMV8_IDX_CYCLE_COUNTER); } @@ -345,7 +358,7 @@ static inline void armv8pmu_select_counter(int idx) isb(); } -static inline u32 armv8pmu_read_evcntr(int idx) +static inline u64 armv8pmu_read_evcntr(int idx) { armv8pmu_select_counter(idx); return read_sysreg(pmxevcntr_el0); @@ -362,6 +375,44 @@ static inline u64 armv8pmu_read_hw_counter(struct perf_event *event) return val; } +/* + * The cycle counter is always a 64-bit counter. When ARMV8_PMU_PMCR_LP + * is set the event counters also become 64-bit counters. Unless the + * user has requested a long counter (attr.config1) then we want to + * interrupt upon 32-bit overflow - we achieve this by applying a bias. + */ +static bool armv8pmu_event_needs_bias(struct perf_event *event) +{ + struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + if (armv8pmu_event_is_64bit(event)) + return false; + + if (armv8pmu_has_long_event(cpu_pmu) || + idx == ARMV8_IDX_CYCLE_COUNTER) + return true; + + return false; +} + +static u64 armv8pmu_bias_long_counter(struct perf_event *event, u64 value) +{ + if (armv8pmu_event_needs_bias(event)) + value |= GENMASK(63, 32); + + return value; +} + +static u64 armv8pmu_unbias_long_counter(struct perf_event *event, u64 value) +{ + if (armv8pmu_event_needs_bias(event)) + value &= ~GENMASK(63, 32); + + return value; +} + static u64 armv8pmu_read_counter(struct perf_event *event) { struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu); @@ -377,10 +428,10 @@ static u64 armv8pmu_read_counter(struct perf_event *event) else value = armv8pmu_read_hw_counter(event); - return value; + return armv8pmu_unbias_long_counter(event, value); } -static inline void armv8pmu_write_evcntr(int idx, u32 value) +static inline void armv8pmu_write_evcntr(int idx, u64 value) { armv8pmu_select_counter(idx); write_sysreg(value, pmxevcntr_el0); @@ -405,20 +456,14 @@ static void armv8pmu_write_counter(struct perf_event *event, u64 value) struct hw_perf_event *hwc = &event->hw; int idx = hwc->idx; + value = armv8pmu_bias_long_counter(event, value); + if (!armv8pmu_counter_valid(cpu_pmu, idx)) pr_err("CPU%u writing wrong counter %d\n", smp_processor_id(), idx); - else if (idx == ARMV8_IDX_CYCLE_COUNTER) { - /* - * The cycles counter is really a 64-bit counter. - * When treating it as a 32-bit counter, we only count - * the lower 32 bits, and set the upper 32-bits so that - * we get an interrupt upon 32-bit overflow. - */ - if (!armv8pmu_event_is_64bit(event)) - value |= 0xffffffff00000000ULL; + else if (idx == ARMV8_IDX_CYCLE_COUNTER) write_sysreg(value, pmccntr_el0); - } else + else armv8pmu_write_hw_counter(event, value); } @@ -743,7 +788,8 @@ static int armv8pmu_get_event_idx(struct pmu_hw_events *cpuc, /* * Otherwise use events counters */ - if (armv8pmu_event_is_64bit(event)) + if (armv8pmu_event_is_64bit(event) && + !armv8pmu_has_long_event(cpu_pmu)) return armv8pmu_get_chain_idx(cpuc, cpu_pmu); else return armv8pmu_get_single_idx(cpuc, cpu_pmu); @@ -815,7 +861,7 @@ static int armv8pmu_filter_match(struct perf_event *event) static void armv8pmu_reset(void *info) { struct arm_pmu *cpu_pmu = (struct arm_pmu *)info; - u32 idx, nb_cnt = cpu_pmu->num_events; + u32 idx, pmcr, nb_cnt = cpu_pmu->num_events; /* The counter and interrupt enable registers are unknown at reset. */ for (idx = ARMV8_IDX_CYCLE_COUNTER; idx < nb_cnt; ++idx) { @@ -830,8 +876,13 @@ static void armv8pmu_reset(void *info) * Initialize & Reset PMNC. Request overflow interrupt for * 64 bit cycle counter but cheat in armv8pmu_write_counter(). */ - armv8pmu_pmcr_write(ARMV8_PMU_PMCR_P | ARMV8_PMU_PMCR_C | - ARMV8_PMU_PMCR_LC); + pmcr = ARMV8_PMU_PMCR_P | ARMV8_PMU_PMCR_C | ARMV8_PMU_PMCR_LC; + + /* Enable long event counter support where available */ + if (armv8pmu_has_long_event(cpu_pmu)) + pmcr |= ARMV8_PMU_PMCR_LP; + + armv8pmu_pmcr_write(pmcr); } static int __armv8_pmuv3_map_event(struct perf_event *event, @@ -914,6 +965,7 @@ static void __armv8pmu_probe_pmu(void *info) if (pmuver == 0xf || pmuver == 0) return; + cpu_pmu->pmuver = pmuver; probe->present = true; /* Read the nb of CNTx counters supported from PMNC */ diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h index 71f525a35ac2..5b616dde9a4c 100644 --- a/include/linux/perf/arm_pmu.h +++ b/include/linux/perf/arm_pmu.h @@ -80,6 +80,7 @@ struct arm_pmu { struct pmu pmu; cpumask_t supported_cpus; char *name; + int pmuver; irqreturn_t (*handle_irq)(struct arm_pmu *pmu); void (*enable)(struct perf_event *event); void (*disable)(struct perf_event *event);