From nobody Sun Feb 8 05:35:25 2026 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 52E9927B34E; Sat, 10 Jan 2026 19:46:00 +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=1768074363; cv=none; b=HyYxe0U9UrG4MmPXH1XgsXcZzw80xiszVl792ZqV+RZa/nD53WVJOfz9oxqhGsJDcXSmWwzyb2ye4HyBUhvDQMeyXfpGoEP0j9xPXMdr7mnkeES96G5vyvhsP2GIM9sFDtT2ylEVrlI4lx0n3MDgvjqNr8KJkzJRK6UKCIgStq8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768074363; c=relaxed/simple; bh=/LAOV+Ff61CSvfyrY5L2KmgVLcabWZipv04s05ZJCfo=; h=Date:From:To:Subject:Cc:MIME-Version:Message-ID:Content-Type; b=rwnTdG6KZPv/MnYRdpY9Bul5B6Xot34ItFMBG1v+KF1g3EH0pvUn5htUB8h+L6nqTsG/VQ3qQUMJrr0NVMSGiFJV1aLcZ3WdGVMB7eoquBCM+zz2M2EpJ+XH8M2WtxhIGMGKIyrUqhBLOquEHWj0G5G6LPZrynMXZIOIm2BkbW8= 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=CQACIMqU; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=DHqdZXP7; 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="CQACIMqU"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="DHqdZXP7" Date: Sat, 10 Jan 2026 19:45:56 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1768074357; 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; bh=TPEbHqe1uPycFyttd3bzZoDC9rFLGxIgSg4Vq1EaLF0=; b=CQACIMqUkvy4Y/xi6D4exgWSWb7n2ZSP1PrVooCJ9syrWHY6jT2viR0iumFxK0Sm+VePjD fl+cTmQLZc/1MYj7EEYn91wlZmUW2XXF3M54WrWtAUdacuSqR3nJkmKjHu3m1iS8oKqhbc J6MrbDB5achAY/qwYfbHwiJtTdw5O5ZZMNd1C5SUBcs1v31JeKXF1z4Pcbj438AwzljUCP 9U6Beb8Z+pJjO9OMyrj8P/PN+2qaYFmXSrxUrHjcuLx+a4A/jJpw8KhJwIikEPI16YSwLG 2NKfDUzrHtZ9XHkgRBOda5R8QSleImT3M4AjCvKIi++BcHc86oFQjhjXOUA0gQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1768074357; 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; bh=TPEbHqe1uPycFyttd3bzZoDC9rFLGxIgSg4Vq1EaLF0=; b=DHqdZXP7JfsRMb86rtii48itNuSW7A7WdXXyGX8aiEFT6wBYEwUuod8u0DyKKL86Kxcpvv RCpYoEpj65PCS8DA== From: "tip-bot2 for Tony Luck" 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 energy/perf choices to rdt boot option Cc: Tony Luck , "Borislav Petkov (AMD)" , Reinette Chatre , x86@kernel.org, linux-kernel@vger.kernel.org Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <176807435671.510.2188274998747953660.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: 842e7f97d71a4116a650ec0045d6444b4377b512 Gitweb: https://git.kernel.org/tip/842e7f97d71a4116a650ec0045d6444b4= 377b512 Author: Tony Luck AuthorDate: Wed, 17 Dec 2025 09:21:11 -08:00 Committer: Borislav Petkov (AMD) CommitterDate: Fri, 09 Jan 2026 23:38:32 +01:00 x86/resctrl: Add energy/perf choices to rdt boot option Legacy resctrl features are enumerated by X86_FEATURE_* flags. These may be overridden by quirks to disable features in the case of errata. Users can = use kernel command line options to either disable a feature, or to force enable a feature that was disabled by a quirk. A different approach is needed for hardware features that do not have an X86_FEATURE_* flag. Update parsing of the "rdt=3D" boot parameter to call the telemetry driver directly to handle new "perf" and "energy" options that controls activation= of telemetry monitoring of the named type. By itself a "perf" or "energy" opti= on controls the forced enabling or disabling (with ! prefix) of all event grou= ps of the named type. A ":guid" suffix allows for fine grained control per eve= nt group. [ bp: s/intel_aet_option/intel_handle_aet_option/g ] Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com --- Documentation/admin-guide/kernel-parameters.txt | 7 ++- arch/x86/kernel/cpu/resctrl/core.c | 2 +- arch/x86/kernel/cpu/resctrl/intel_aet.c | 38 ++++++++++++++++- arch/x86/kernel/cpu/resctrl/internal.h | 2 +- 4 files changed, 48 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index a8d0afd..abd77f3 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6325,9 +6325,14 @@ Kernel parameters rdt=3D [HW,X86,RDT] Turn on/off individual RDT features. List is: cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, l2cdp, - mba, smba, bmec, abmc, sdciae. + mba, smba, bmec, abmc, sdciae, energy[:guid], + perf[:guid]. E.g. to turn on cmt and turn off mba use: rdt=3Dcmt,!mba + To turn off all energy telemetry monitoring and ensure that + perf telemetry monitoring associated with guid 0x12345 + is enabled use: + rdt=3D!energy,perf:0x12345 =20 reboot=3D [KNL] Format (x86 or x86_64): diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resct= rl/core.c index 2514f15..e38d7fc 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -814,6 +814,8 @@ static int __init set_rdt_options(char *str) force_off =3D *tok =3D=3D '!'; if (force_off) tok++; + if (intel_handle_aet_option(force_off, tok)) + continue; for (o =3D rdt_options; o < &rdt_options[NUM_RDT_OPTIONS]; o++) { if (strcmp(tok, o->name) =3D=3D 0) { if (force_off) diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/= resctrl/intel_aet.c index 9351fe5..dc25e8d 100644 --- a/arch/x86/kernel/cpu/resctrl/intel_aet.c +++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c @@ -52,12 +52,17 @@ struct pmt_event { /** * struct event_group - Events with the same feature type ("energy" or "pe= rf") and GUID. * @pfname: PMT feature name ("energy" or "perf") of this event group. + * Used by boot rdt=3D option. * @pfg: Points to the aggregated telemetry space information * returned by the intel_pmt_get_regions_by_feature() * call to the INTEL_PMT_TELEMETRY driver that contains * data for all telemetry regions of type @pfname. * Valid if the system supports the event group, * NULL otherwise. + * @force_off: True when "rdt" command line or architecture code disables + * this event group. + * @force_on: True when "rdt" command line overrides disable of this + * event group. * @guid: Unique number per XML description file. * @mmio_size: Number of bytes of MMIO registers for this group. * @num_events: Number of events in this group. @@ -67,6 +72,7 @@ struct event_group { /* Data fields for additional structures to manage this group. */ const char *pfname; struct pmt_feature_group *pfg; + bool force_off, force_on; =20 /* Remaining fields initialized from XML file. */ u32 guid; @@ -121,6 +127,35 @@ static struct event_group *known_event_groups[] =3D { _peg < &known_event_groups[ARRAY_SIZE(known_event_groups)]; \ _peg++) =20 +bool intel_handle_aet_option(bool force_off, char *tok) +{ + struct event_group **peg; + bool ret =3D false; + u32 guid =3D 0; + char *name; + + if (!tok) + return false; + + name =3D strsep(&tok, ":"); + if (tok && kstrtou32(tok, 16, &guid)) + return false; + + for_each_event_group(peg) { + if (strcmp(name, (*peg)->pfname)) + continue; + if (guid && (*peg)->guid !=3D guid) + continue; + if (force_off) + (*peg)->force_off =3D true; + else + (*peg)->force_on =3D true; + ret =3D true; + } + + return ret; +} + static bool skip_telem_region(struct telemetry_region *tr, struct event_gr= oup *e) { if (tr->guid !=3D e->guid) @@ -168,6 +203,9 @@ static bool enable_events(struct event_group *e, struct= pmt_feature_group *p) struct rdt_resource *r =3D &rdt_resources_all[RDT_RESOURCE_PERF_PKG].r_re= sctrl; int skipped_events =3D 0; =20 + if (e->force_off) + return false; + if (!group_has_usable_regions(e, p)) return false; =20 diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/r= esctrl/internal.h index 3b228b2..61a2836 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -236,6 +236,7 @@ void __exit intel_aet_exit(void); int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val); void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_resource *r, struct list_head *add_pos); +bool intel_handle_aet_option(bool force_off, char *tok); #else static inline bool intel_aet_get_events(void) { return false; } static inline void __exit intel_aet_exit(void) { } @@ -246,6 +247,7 @@ static inline int intel_aet_read_event(int domid, u32 r= mid, void *arch_priv, u64 =20 static inline void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_= resource *r, struct list_head *add_pos) { } +static inline bool intel_handle_aet_option(bool force_off, char *tok) { re= turn false; } #endif =20 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */