From patchwork Wed Jul 31 08:36:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomas Glozar X-Patchwork-Id: 13748266 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A015F1A8C02 for ; Wed, 31 Jul 2024 08:38:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722415140; cv=none; b=apXkfbbTpB7K0oasj4gFFwc8z55MSQF4Y9kheM98eHgMYanSpfOjV5tLLtAIpQzxH3kNnGZ4msud9nXEj0WQSuMqDq4gDEv3Sqqw4L5OwATjz0PgltHKX9nqUDujy8FhJhpxxo9zuFBYdvTc5EUGXnDopuwMuEDHVDC9j1bCovg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722415140; c=relaxed/simple; bh=13bOdv7scmfFCaUBtenmb+HF0x94sj9x9FW4ztglD9o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dIrpaZC3494tEPvdZSTBbqZUeO3CDdmaar3NnAP1ToKGi2rzb6bklw1U7/+5doEEHZqpGNwFTqMugghHbqpsHVUMUgNykKeo4nZWhbOfGu2okbZMBbY1nOmbtOxdMXDhqjCc0RvQAKjKHpe4VYhX3cSATBIwbcQYiL1LEFkEuUM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=h22czb2O; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="h22czb2O" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1722415137; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ns3mAFHi4DBzVE9smck0+0QW9qVWnxn0yJIN53GD66w=; b=h22czb2OWxEOLZDC6jkgpyyIZ34i0rDqGjn2aNk22AsVdV9hyHzDedc0n6ziBwvKazwmY1 BnWjzFzFQ+Gd1hHSVqHiRWQGtr9htrNik8mq/B+Yeg0iomFQVTvrsZThtxZuJVV2EG3mTZ QtDULmbhFdI7PFCt85JF/z0/EWzpOaA= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-344-EHq9BLPRO4WTYFJmVWr96w-1; Wed, 31 Jul 2024 04:38:50 -0400 X-MC-Unique: EHq9BLPRO4WTYFJmVWr96w-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 73C421955D48; Wed, 31 Jul 2024 08:38:49 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.45.224.159]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 3D451300018D; Wed, 31 Jul 2024 08:38:46 +0000 (UTC) From: tglozar@redhat.com To: rostedt@goodmis.org Cc: linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, jwyatt@redhat.com, jkacur@redhat.com, Tomas Glozar Subject: [PATCH v2 3/6] rtla/utils: Add idle state disabling via libcpupower Date: Wed, 31 Jul 2024 10:36:52 +0200 Message-ID: <20240731083655.375293-4-tglozar@redhat.com> In-Reply-To: <20240731083655.375293-1-tglozar@redhat.com> References: <20240731083655.375293-1-tglozar@redhat.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 From: Tomas Glozar Add functions to utils.c to disable idle states through functions of libcpupower. This will serve as the basis for disabling idle states per cpu when running timerlat. Signed-off-by: Tomas Glozar --- tools/tracing/rtla/src/utils.c | 140 +++++++++++++++++++++++++++++++++ tools/tracing/rtla/src/utils.h | 6 ++ 2 files changed, 146 insertions(+) diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index 9ac71a66840c..9279b8ce08c3 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -4,6 +4,9 @@ */ #define _GNU_SOURCE +#ifdef HAVE_LIBCPUPOWER_SUPPORT +#include +#endif /* HAVE_LIBCPUPOWER_SUPPORT */ #include #include #include @@ -519,6 +522,143 @@ int set_cpu_dma_latency(int32_t latency) return fd; } +#ifdef HAVE_LIBCPUPOWER_SUPPORT +static unsigned int **saved_cpu_idle_disable_state; +static size_t saved_cpu_idle_disable_state_alloc_ctr; + +/* + * save_cpu_idle_state_disable - save disable for all idle states of a cpu + * + * Saves the current disable of all idle states of a cpu, to be subsequently + * restored via restore_cpu_idle_disable_state. + * + * Return: idle state count on success, negative on error + */ +int save_cpu_idle_disable_state(unsigned int cpu) +{ + unsigned int nr_states; + unsigned int state; + int disabled; + int nr_cpus; + + nr_states = cpuidle_state_count(cpu); + + if (nr_states == 0) + return 0; + + if (saved_cpu_idle_disable_state == NULL) { + nr_cpus = sysconf(_SC_NPROCESSORS_CONF); + saved_cpu_idle_disable_state = calloc(nr_cpus, sizeof(unsigned int *)); + } + + saved_cpu_idle_disable_state[cpu] = calloc(nr_states, sizeof(unsigned int)); + saved_cpu_idle_disable_state_alloc_ctr++; + + for (state = 0; state < nr_states; state++) { + disabled = cpuidle_is_state_disabled(cpu, state); + if (disabled < 0) + return disabled; + saved_cpu_idle_disable_state[cpu][state] = disabled; + } + + return nr_states; +} + +/* + * restore_cpu_idle_disable_state - restore disable for all idle states of a cpu + * + * Restores the current disable state of all idle states of a cpu that was + * previously saved by save_cpu_idle_disable_state. + * + * Return: idle state count on success, negative on error + */ +int restore_cpu_idle_disable_state(unsigned int cpu) +{ + unsigned int nr_states; + unsigned int state; + int disabled; + int result; + + nr_states = cpuidle_state_count(cpu); + + if (nr_states == 0) + return 0; + + for (state = 0; state < nr_states; state++) { + disabled = saved_cpu_idle_disable_state[cpu][state]; + result = cpuidle_state_disable(cpu, state, disabled); + if (result < 0) + return result; + } + + free(saved_cpu_idle_disable_state[cpu]); + saved_cpu_idle_disable_state[cpu] = NULL; + saved_cpu_idle_disable_state_alloc_ctr--; + if (saved_cpu_idle_disable_state_alloc_ctr == 0) { + free(saved_cpu_idle_disable_state); + saved_cpu_idle_disable_state = NULL; + } + + return nr_states; +} + +/* + * free_cpu_idle_disable_states - free saved idle state disable for all cpus + * + * Frees the memory used for storing cpu idle state disable for all cpus + * and states. + * + * Normally, the memory is freed automatically in + * restore_cpu_idle_disable_state; this is mostly for cleaning up after an + * error. + */ +void free_cpu_idle_disable_states(void) +{ + int cpu; + + if (!saved_cpu_idle_disable_state) + return; + + for (cpu = 0; cpu < sysconf(_SC_NPROCESSORS_CONF); cpu++) { + if (!saved_cpu_idle_disable_state[cpu]) + continue; + free(saved_cpu_idle_disable_state[cpu]); + saved_cpu_idle_disable_state[cpu] = NULL; + } + + free(saved_cpu_idle_disable_state); + saved_cpu_idle_disable_state = NULL; +} + +/* + * set_deepest_cpu_idle_state - limit idle state of cpu + * + * Disables all idle states deeper than the one given in + * deepest_state (assuming states with higher number are deeper). + * + * This is used to reduce the exit from idle latency. Unlike + * set_cpu_dma_latency, it can disable idle states per cpu. + * + * Return: idle state count on success, negative on error + */ +int set_deepest_cpu_idle_state(unsigned int cpu, unsigned int deepest_state) +{ + unsigned int nr_states; + unsigned int state; + int result; + + nr_states = cpuidle_state_count(cpu); + + for (state = deepest_state + 1; state < nr_states; state++) { + result = cpuidle_state_disable(cpu, state, 1); + if (result < 0) + return result; + } + + return nr_states; +} +#endif /* HAVE_LIBCPUPOWER_SUPPORT */ + #define _STR(x) #x #define STR(x) _STR(x) diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h index d44513e6c66a..51b6054c2679 100644 --- a/tools/tracing/rtla/src/utils.h +++ b/tools/tracing/rtla/src/utils.h @@ -64,6 +64,12 @@ int set_comm_sched_attr(const char *comm_prefix, struct sched_attr *attr); int set_comm_cgroup(const char *comm_prefix, const char *cgroup); int set_pid_cgroup(pid_t pid, const char *cgroup); int set_cpu_dma_latency(int32_t latency); +#ifdef HAVE_LIBCPUPOWER_SUPPORT +int save_cpu_idle_disable_state(unsigned int cpu); +int restore_cpu_idle_disable_state(unsigned int cpu); +void free_cpu_idle_disable_states(void); +int set_deepest_cpu_idle_state(unsigned int cpu, unsigned int state); +#endif /* HAVE_LIBCPUPOWER_SUPPORT */ int auto_house_keeping(cpu_set_t *monitored_cpus); #define ns_to_usf(x) (((double)x/1000))