From nobody Fri Dec 19 07:32:34 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A7796180A82 for ; Fri, 14 Jun 2024 15:01:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718377297; cv=none; b=J4V28pok10jFhLcNwpXP2l26Dpa8+6Sie+Sn4Kzrjrm2E61uvy47NfB+RpWA2u2ooqxlrWxju9nrEnwLvwKXEOW1e84zdZMfv9Z763F4fkNsVBz65e3+Dvgh4QdyuawBkTC+Ezdnh6XwGn2um3DPFTJBMQGIjDe42XBjqJjQ4Zg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718377297; c=relaxed/simple; bh=NenhoyqBq6bytTT60YBOfDFkbHPR4uWsS3eErMDe4fI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=FCheMJxCEka/2C22W6jYRLicI8Rs9SPEFQ8YsVEwVRaDHpZ5NyrbozzzARzqCzQ0jT8wwnJkeWOkOF1eRaAkcGWgMPNJrRMCsp0nk6+ugam+gVDlGeYU/YXGOHYH5lOIr76eDQg8Ak7tRwad69PmzmnzOI9+u93tQEg7Y6HEfL4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 7E42616F2; Fri, 14 Jun 2024 08:01:59 -0700 (PDT) Received: from merodach.members.linode.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E6FF23F5A1; Fri, 14 Jun 2024 08:01:31 -0700 (PDT) From: James Morse To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Fenghua Yu , Reinette Chatre , Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , Babu Moger , James Morse , shameerali.kolothum.thodi@huawei.com, D Scott Phillips OS , carl@os.amperecomputing.com, lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, baolin.wang@linux.alibaba.com, Jamie Iles , Xin Hao , peternewman@google.com, dfustini@baylibre.com, amitsinght@marvell.com, David Hildenbrand , Rex Nie , Dave Martin Subject: [PATCH v3 08/38] x86/resctrl: Generate default_ctrl instead of sharing it Date: Fri, 14 Jun 2024 15:00:03 +0000 Message-Id: <20240614150033.10454-9-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20240614150033.10454-1-james.morse@arm.com> References: <20240614150033.10454-1-james.morse@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The struct rdt_resource default_ctrl is used by both the architecture code for resetting the hardware controls, and by the filesystem parts of resctrl to report to user-space. This means the value has to be shared, but might not match the properties of the control. e.g. a percentage greater than 100. Instead, determine the default control value from a shared helper resctrl_get_default_ctrl() that uses the schema properties to determine the correct value. Signed-off-by: James Morse --- Changes since v2: * This patch is new. --- arch/x86/kernel/cpu/resctrl/core.c | 16 +++++++--------- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 6 +++--- include/linux/resctrl.h | 21 +++++++++++++++++++-- 3 files changed, 29 insertions(+), 14 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resct= rl/core.c index c1dfc1466e53..9241f3ff3870 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -137,7 +137,10 @@ static inline void cache_alloc_hsw_probe(void) { struct rdt_hw_resource *hw_res =3D &rdt_resources_all[RDT_RESOURCE_L3]; struct rdt_resource *r =3D &hw_res->r_resctrl; - u64 max_cbm =3D BIT_ULL_MASK(20) - 1, l3_cbm_0; + u64 max_cbm, l3_cbm_0; + + r->cache.cbm_len =3D 20; + max_cbm =3D resctrl_get_default_ctrl(r); =20 if (wrmsrl_safe(MSR_IA32_L3_CBM_BASE, max_cbm)) return; @@ -149,8 +152,6 @@ static inline void cache_alloc_hsw_probe(void) return; =20 hw_res->num_closid =3D 4; - r->default_ctrl =3D max_cbm; - r->cache.cbm_len =3D 20; r->cache.shareable_bits =3D 0xc0000; r->cache.min_cbm_bits =3D 2; r->cache.arch_has_sparse_bitmasks =3D false; @@ -205,7 +206,6 @@ static bool __get_mem_config_intel(struct rdt_resource = *r) cpuid_count(0x00000010, 3, &eax.full, &ebx, &ecx, &edx.full); hw_res->num_closid =3D edx.split.cos_max + 1; max_delay =3D eax.split.max_delay + 1; - r->default_ctrl =3D MAX_MBA_BW; r->membw.max_bw =3D MAX_MBA_BW; r->membw.arch_needs_linear =3D true; if (ecx & MBA_IS_LINEAR) { @@ -242,7 +242,6 @@ static bool __rdt_get_mem_config_amd(struct rdt_resourc= e *r) =20 cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx); hw_res->num_closid =3D edx + 1; - r->default_ctrl =3D 1 << eax; r->schema_fmt =3D RESCTRL_SCHEMA_MBPS; r->membw.max_bw =3D 1 << eax; =20 @@ -274,8 +273,7 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt= _resource *r) cpuid_count(0x00000010, idx, &eax.full, &ebx, &ecx.full, &edx.full); hw_res->num_closid =3D edx.split.cos_max + 1; r->cache.cbm_len =3D eax.split.cbm_len + 1; - r->default_ctrl =3D BIT_MASK(eax.split.cbm_len + 1) - 1; - r->cache.shareable_bits =3D ebx & r->default_ctrl; + r->cache.shareable_bits =3D ebx & resctrl_get_default_ctrl(r); if (boot_cpu_data.x86_vendor =3D=3D X86_VENDOR_INTEL) r->cache.arch_has_sparse_bitmasks =3D ecx.split.noncont; r->alloc_capable =3D true; @@ -322,7 +320,7 @@ static u32 delay_bw_map(unsigned long bw, struct rdt_re= source *r) return MAX_MBA_BW - bw; =20 pr_warn_once("Non Linear delay-bw map not supported but queried\n"); - return r->default_ctrl; + return resctrl_get_default_ctrl(r); } =20 static void mba_wrmsr_intel(struct msr_param *m) @@ -419,7 +417,7 @@ static void setup_default_ctrlval(struct rdt_resource *= r, u32 *dc) * For Memory Allocation: Set b/w requested to 100% */ for (i =3D 0; i < hw_res->num_closid; i++, dc++) - *dc =3D r->default_ctrl; + *dc =3D resctrl_get_default_ctrl(r); } =20 static void domain_free(struct rdt_hw_domain *hw_dom) diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/r= esctrl/rdtgroup.c index 4f8e20cc06eb..ba43173d5b66 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -970,7 +970,7 @@ static int rdt_default_ctrl_show(struct kernfs_open_fil= e *of, struct resctrl_schema *s =3D of->kn->parent->priv; struct rdt_resource *r =3D s->res; =20 - seq_printf(seq, "%x\n", r->default_ctrl); + seq_printf(seq, "%x\n", resctrl_get_default_ctrl(r)); return 0; } =20 @@ -2869,7 +2869,7 @@ static int reset_all_ctrls(struct rdt_resource *r) hw_dom =3D resctrl_to_arch_dom(d); =20 for (i =3D 0; i < hw_res->num_closid; i++) - hw_dom->ctrl_val[i] =3D r->default_ctrl; + hw_dom->ctrl_val[i] =3D resctrl_get_default_ctrl(r); msr_param.dom =3D d; smp_call_function_any(&d->cpu_mask, rdt_ctrl_update, &msr_param, 1); } @@ -3340,7 +3340,7 @@ static void rdtgroup_init_mba(struct rdt_resource *r,= u32 closid) } =20 cfg =3D &d->staged_config[CDP_NONE]; - cfg->new_ctrl =3D r->default_ctrl; + cfg->new_ctrl =3D resctrl_get_default_ctrl(r); cfg->have_new_ctrl =3D true; } } diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index 0dee50530847..cc491a03def8 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -184,7 +184,6 @@ enum resctrl_schema_fmt { * @membw: If the component has bandwidth controls, their properties. * @domains: RCU list of all domains for this resource * @name: Name to use in "schemata" file. - * @default_ctrl: Specifies default cache cbm or memory B/W percent. * @schema_fmt: Which format string and parser is used for this schema. * @evt_list: List of monitoring events * @cdp_capable: Is the CDP feature available on this resource @@ -199,7 +198,6 @@ struct rdt_resource { struct resctrl_membw membw; struct list_head domains; char *name; - u32 default_ctrl; enum resctrl_schema_fmt schema_fmt; struct list_head evt_list; bool cdp_capable; @@ -236,6 +234,25 @@ struct resctrl_schema { u32 num_closid; }; =20 +/** + * resctrl_get_default_ctrl() - Return the default control value for this + * resource. + * @r: The resource whose default control type is queried. + */ +static inline u32 resctrl_get_default_ctrl(struct rdt_resource *r) +{ + switch (r->schema_fmt) { + case RESCTRL_SCHEMA_BITMAP: + return BIT_MASK(r->cache.cbm_len) - 1; + case RESCTRL_SCHEMA_PERCENTAGE: + return 100u; + case RESCTRL_SCHEMA_MBPS: + return r->membw.max_bw; + } + + return WARN_ON_ONCE(1); +} + /* The number of closid supported by this resource regardless of CDP */ u32 resctrl_arch_get_num_closid(struct rdt_resource *r); int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid); --=20 2.39.2