From nobody Sat May 18 08:46:56 2024 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 EA4751DFF8; Wed, 24 Apr 2024 12:34:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713962088; cv=none; b=aMAqYzi/WSdcm7pOZYp4KbTRTWquW3nq33b8aRFc/yKPmeJoyup//O47WvuZwQv5O7VQPb5bcDlBfEOnZJRz3msgbWUhN8xmQ3L3J7cNy5hwzUkgB2LSvEAiB9n0/6KhttWMnBlU63gBszy4YC+pa21ScEcwm4Ocb0550LemBEg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713962088; c=relaxed/simple; bh=M/CykXs7tLVB+wjotgza7K2AlgcNOsKL5CfCon2EmNI=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=G1/4L8lmgN/29AL8KdrQtTJFlMdps5abKihc7+q0PULMvSywdcQHPbCtI2b5JQQvJYDTRpn5kHZEfobv8XGa5Fjrqu0Lv1iMhwxHjmFK6LuyNDV2Koh6BEMfdpqcN+PR6h2aY6uMsXhxaAWfxm1Rr/DFHjO71AJKb1rdPYc325c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=ySRaNXIW; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=GdKLBIJT; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="ySRaNXIW"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="GdKLBIJT" Date: Wed, 24 Apr 2024 12:34:44 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1713962085; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9Avw2ZT5I1sz1g/0+oR3KsqSJGaVsQEsTbl2M9mSNnA=; b=ySRaNXIWAmQkQ+j0LwdOEjzsoTNl977x08/NoCFVLMu/vwpxTlo4RIIetHNZwC/c/oOUj2 eIlZY1Mf3fl1Cn89cQIYT70VPO0LDnTYNzEP/yQLMB0POqlH3470g4HGERAqGidNWjNavY vGseF7hd7yo27XDi5NhnEDzXTcar95AHwcs7qOmO75UK5rVILlCpGXWXZxDCNWBnVaeL0t o0h4o6F7G2c6v81nSK5h4W0lBt16+YsTFtonvETSBNsDe7CZ1wTthcUZKFWnoaW/V3EOER x1XGz+G7ZQG3EmqW/4NutFGG3QbLDvAZxBiJ/nSCce9c5pYabgyl1QBgc3JRRA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1713962085; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9Avw2ZT5I1sz1g/0+oR3KsqSJGaVsQEsTbl2M9mSNnA=; b=GdKLBIJTQ7FXCjULHS6Sy81mxAgiRYsGCNfO9q7ygpAjNsIEarEhgCDLcHyGS6r7vPJ8tG WOIfjY8YYRv0l0DQ== From: "tip-bot2 for Haifeng Xu" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/cache] x86/resctrl: Add tracepoint for llc_occupancy tracking Cc: Reinette Chatre , James Morse , Haifeng Xu , "Borislav Petkov (AMD)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20240408092303.26413-3-haifeng.xu@shopee.com> References: <20240408092303.26413-3-haifeng.xu@shopee.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <171396208407.10875.3076169183667430328.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the x86/cache branch of tip: Commit-ID: 931be446c6cbc15691dd499957e961f4e1d56afb Gitweb: https://git.kernel.org/tip/931be446c6cbc15691dd499957e961f4e= 1d56afb Author: Haifeng Xu AuthorDate: Mon, 08 Apr 2024 17:23:03 +08:00 Committer: Borislav Petkov (AMD) CommitterDate: Wed, 24 Apr 2024 14:24:48 +02:00 x86/resctrl: Add tracepoint for llc_occupancy tracking In our production environment, after removing monitor groups, those unused RMIDs get stuck in the limbo list forever because their llc_occupancy is always larger than the threshold. But the unused RMIDs can be successfully freed by turning up the threshold. In order to know how much the threshold should be, perf can be used to acquire the llc_occupancy of RMIDs in each rdt domain. Instead of using perf tool to track llc_occupancy and filter the log manually, it is more convenient for users to use tracepoint to do this work. So add a new tracepoint that shows the llc_occupancy of busy RMIDs when scanning the limbo list. Suggested-by: Reinette Chatre Suggested-by: James Morse Signed-off-by: Haifeng Xu Signed-off-by: Borislav Petkov (AMD) Reviewed-by: James Morse Reviewed-by: Reinette Chatre Link: https://lore.kernel.org/r/20240408092303.26413-3-haifeng.xu@shopee.com --- Documentation/arch/x86/resctrl.rst | 6 ++++++ arch/x86/kernel/cpu/resctrl/monitor.c | 11 +++++++++++ arch/x86/kernel/cpu/resctrl/trace.h | 16 ++++++++++++++++ 3 files changed, 33 insertions(+) diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/re= sctrl.rst index 6c24558..627e238 100644 --- a/Documentation/arch/x86/resctrl.rst +++ b/Documentation/arch/x86/resctrl.rst @@ -446,6 +446,12 @@ during mkdir. max_threshold_occupancy is a user configurable value to determine the occupancy at which an RMID can be freed. =20 +The mon_llc_occupancy_limbo tracepoint gives the precise occupancy in bytes +for a subset of RMID that are not immediately available for allocation. +This can't be relied on to produce output every second, it may be necessary +to attempt to create an empty monitor group to force an update. Output may +only be produced if creation of a control or monitor group fails. + Schemata files - general concepts --------------------------------- Each line in the file describes one resource. The line starts with diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/re= sctrl/monitor.c index c34a35e..2345e68 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -24,6 +24,7 @@ #include =20 #include "internal.h" +#include "trace.h" =20 /** * struct rmid_entry - dirty tracking for all RMID. @@ -354,6 +355,16 @@ void __check_limbo(struct rdt_domain *d, bool force_fr= ee) rmid_dirty =3D true; } else { rmid_dirty =3D (val >=3D resctrl_rmid_realloc_threshold); + + /* + * x86's CLOSID and RMID are independent numbers, so the entry's + * CLOSID is an empty CLOSID (X86_RESCTRL_EMPTY_CLOSID). On Arm the + * RMID (PMG) extends the CLOSID (PARTID) space with bits that aren't + * used to select the configuration. It is thus necessary to track both + * CLOSID and RMID because there may be dependencies between them + * on some architectures. + */ + trace_mon_llc_occupancy_limbo(entry->closid, entry->rmid, d->id, val); } =20 if (force_free || !rmid_dirty) { diff --git a/arch/x86/kernel/cpu/resctrl/trace.h b/arch/x86/kernel/cpu/resc= trl/trace.h index 495fb90..2a50631 100644 --- a/arch/x86/kernel/cpu/resctrl/trace.h +++ b/arch/x86/kernel/cpu/resctrl/trace.h @@ -35,6 +35,22 @@ TRACE_EVENT(pseudo_lock_l3, TP_printk("hits=3D%llu miss=3D%llu", __entry->l3_hits, __entry->l3_miss)); =20 +TRACE_EVENT(mon_llc_occupancy_limbo, + TP_PROTO(u32 ctrl_hw_id, u32 mon_hw_id, int domain_id, u64 llc_occupa= ncy_bytes), + TP_ARGS(ctrl_hw_id, mon_hw_id, domain_id, llc_occupancy_bytes), + TP_STRUCT__entry(__field(u32, ctrl_hw_id) + __field(u32, mon_hw_id) + __field(int, domain_id) + __field(u64, llc_occupancy_bytes)), + TP_fast_assign(__entry->ctrl_hw_id =3D ctrl_hw_id; + __entry->mon_hw_id =3D mon_hw_id; + __entry->domain_id =3D domain_id; + __entry->llc_occupancy_bytes =3D llc_occupancy_bytes;), + TP_printk("ctrl_hw_id=3D%u mon_hw_id=3D%u domain_id=3D%d llc_occupanc= y_bytes=3D%llu", + __entry->ctrl_hw_id, __entry->mon_hw_id, __entry->domain_id, + __entry->llc_occupancy_bytes) + ); + #endif /* _TRACE_RESCTRL_H */ =20 #undef TRACE_INCLUDE_PATH