From mboxrd@z Thu Jan 1 00:00:00 1970 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 7362950253; Mon, 19 Feb 2024 18:37:36 +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=1708367858; cv=none; b=qDplQ/1LxoEcf953Qlcr3xo4qIac5szAv7Mypv6svWf6uncv0x8hEsse3+ddu+LMNLVWbA6O+v9AOZMoyAumBxGhmxb6hmM3VFCrWNR72NDkEntw8WVbmHgYnyr4GFkK0Trz342qfgldKZ0z+Z4BoFQOoSNXFAKF93LL1cT/OGw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708367858; c=relaxed/simple; bh=ZbbhHE6UUZwGqw0XhucTQNlCcltUp3JDNyecsexFdj8=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=Hswiu/qFUB7c1BbHIL1wrHUJtDTyuxgs0FOWKHifaID0GCCWAz+uRpHcBmeONf6vk9TI8LVsj0UMSUex17HI6TH1usHgDEVxNP659eIby8rsHNe6PRPAuDedwxYbDWBZ+gQJRYdCZToN4xcK4SzMR54I8Qo1onAj7kNyrO4+j7A= 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=T9dhl9wb; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=5cl4VRZe; 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="T9dhl9wb"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="5cl4VRZe" Date: Mon, 19 Feb 2024 18:37:33 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1708367854; 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=6f6pCTjBTNIp0oMTlhFm1Cm0MI2mqcpz6venSi+2MPM=; b=T9dhl9wbHxNISzzU5ziU9G1/h4eF0hQ/R72QZv9VIiAHV08hHcmVmxhbsEJppFoiSls9dN 5StbHh7L4a1KDeFyU4d3u8rAMX4A+CD0iB4Ox+kgtNijwDlIFQMraknPS1R0T24sOX6tpy enXgdV/PY+ZCqeY/uB2i237gcycCujdyNIC+5No39YlHv+R5ZRnhFxeAfcl2ZNvKQ3Zp1b Ulag7ir4Qp2gRFDs2is0aOB5VBPSO2HbV2aB12KFzC5UA338/VnzoHAU8i5ntOhLwMRH8B 6kvJ6n8Cy8bcIT5x9L9nNytIXIKEh+SFMA6SHfrSIrrr6K/lzIl/QQDY1+M+hQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1708367854; 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=6f6pCTjBTNIp0oMTlhFm1Cm0MI2mqcpz6venSi+2MPM=; b=5cl4VRZe8TOSm1rKfyvyaRgmDphJQOIj7/0Opuaz1bxUNbsQTkfoVnGiO0FbQ2w+5r6wmV SHNo9wKkQF7PT6DA== From: "tip-bot2 for James Morse" 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: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid Cc: James Morse , "Borislav Petkov (AMD)" , Shaopeng Tan , Reinette Chatre , Babu Moger , Peter Newman , Carl Worth , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20240213184438.16675-11-james.morse@arm.com> References: <20240213184438.16675-11-james.morse@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <170836785387.398.10584661729291507090.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: 7bit The following commit has been merged into the x86/cache branch of tip: Commit-ID: 6eac36bb9eb0349c983313c71692c19d50b56878 Gitweb: https://git.kernel.org/tip/6eac36bb9eb0349c983313c71692c19d50b56878 Author: James Morse AuthorDate: Tue, 13 Feb 2024 18:44:24 Committer: Borislav Petkov (AMD) CommitterDate: Fri, 16 Feb 2024 19:18:32 +01:00 x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid MPAM's PMG bits extend its PARTID space, meaning the same PMG value can be used for different control groups. This means once a CLOSID is allocated, all its monitoring ids may still be dirty, and held in limbo. Instead of allocating the first free CLOSID, on architectures where CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID is enabled, search closid_num_dirty_rmid[] to find the cleanest CLOSID. The CLOSID found is returned to closid_alloc() for the free list to be updated. Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Reviewed-by: Babu Moger Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Babu Moger Tested-by: Carl Worth # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-11-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) --- arch/x86/kernel/cpu/resctrl/internal.h | 2 +- arch/x86/kernel/cpu/resctrl/monitor.c | 45 +++++++++++++++++++++++++- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 19 ++++++++--- 3 files changed, 61 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index 872ba1a..b7b9d92 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -566,5 +566,7 @@ void rdt_domain_reconfigure_cdp(struct rdt_resource *r); void __init thread_throttle_mode_init(void); void __init mbm_config_rftype_init(const char *config); void rdt_staged_configs_clear(void); +bool closid_allocated(unsigned int closid); +int resctrl_find_cleanest_closid(void); #endif /* _ASM_X86_RESCTRL_INTERNAL_H */ diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c index 13b0c8d..101f1b1 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -386,6 +386,51 @@ static struct rmid_entry *resctrl_find_free_rmid(u32 closid) return ERR_PTR(-ENOSPC); } +/** + * resctrl_find_cleanest_closid() - Find a CLOSID where all the associated + * RMID are clean, or the CLOSID that has + * the most clean RMID. + * + * MPAM's equivalent of RMID are per-CLOSID, meaning a freshly allocated CLOSID + * may not be able to allocate clean RMID. To avoid this the allocator will + * choose the CLOSID with the most clean RMID. + * + * When the CLOSID and RMID are independent numbers, the first free CLOSID will + * be returned. + */ +int resctrl_find_cleanest_closid(void) +{ + u32 cleanest_closid = ~0; + int i = 0; + + lockdep_assert_held(&rdtgroup_mutex); + + if (!IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) + return -EIO; + + for (i = 0; i < closids_supported(); i++) { + int num_dirty; + + if (closid_allocated(i)) + continue; + + num_dirty = closid_num_dirty_rmid[i]; + if (num_dirty == 0) + return i; + + if (cleanest_closid == ~0) + cleanest_closid = i; + + if (num_dirty < closid_num_dirty_rmid[cleanest_closid]) + cleanest_closid = i; + } + + if (cleanest_closid == ~0) + return -ENOSPC; + + return cleanest_closid; +} + /* * For MPAM the RMID value is not unique, and has to be considered with * the CLOSID. The (CLOSID, RMID) pair is allocated on all domains, which diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index bc6e0f8..8fc4620 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -137,13 +137,22 @@ static void closid_init(void) static int closid_alloc(void) { - u32 closid = ffs(closid_free_map); + int cleanest_closid; + u32 closid; lockdep_assert_held(&rdtgroup_mutex); - if (closid == 0) - return -ENOSPC; - closid--; + if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) { + cleanest_closid = resctrl_find_cleanest_closid(); + if (cleanest_closid < 0) + return cleanest_closid; + closid = cleanest_closid; + } else { + closid = ffs(closid_free_map); + if (closid == 0) + return -ENOSPC; + closid--; + } __clear_bit(closid, &closid_free_map); return closid; @@ -163,7 +172,7 @@ void closid_free(int closid) * Return: true if @closid is currently associated with a resource group, * false if @closid is free */ -static bool closid_allocated(unsigned int closid) +bool closid_allocated(unsigned int closid) { lockdep_assert_held(&rdtgroup_mutex);