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[195.250.132.146]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48e3ebcb9cesm23707434f8f.27.2026.10.27.05.37.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Oct 2026 05:37:49 -0700 (PDT) Date: Tue, 27 Oct 2026 13:37:46 +0100 From: Petr Tesarik To: Thorsten Blum , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Hans Peter Anvin , Peter Zijlstra , Juergen Gross Cc: linux-kernel@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v2 0/3] x86/tsc: Remove some magic constants Message-ID: <20261027133746.3ccd4b01@mordecai> In-Reply-To: <20261014132932.1495303-1-ptesarik@suse.com> References: <20261014132932.1495303-1-ptesarik@suse.com> Organization: SUSE LINUX X-Mailer: Claws Mail 4.4.0 (GTK 3.24.53; x86_64-suse-linux-gnu) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Hi all, what about this series? It's not super-important, but neither should it be too hard to review... Petr T On Wed, 14 Oct 2026 15:29:29 +0200 Petr Tesarik wrote: > The TSC code is full of various magic constants, making it difficult to > understand the calculations. This patch series tries to document their > actual meaning. > > No functional change intended, but the code is not bit-for-bit > identical; some 32-bit multiplications are converted into 64-bit > multiplications, because HZ_PER_KHZ is an unsigned long. If anything, > this should reduce the risk of arithmetic overflow. > > Changes from v1: > - Use TICK_NSEC instead of (NSEC_PER_SEC / HZ) > - Use HZ_PER_KHZ and KHZ_PER_MHZ from > > Petr Tesarik (3): > x86/tsc: Replace magic constants with xxx_PER_SEC > x86/tsc: Use HZ_PER_KHZ and KHZ_PER_MHZ > x86/tsc: Use TSC_CALIBRATE_MULT for the TSC multiplier > > arch/x86/kernel/tsc.c | 54 +++++++++++++++++++++---------------------- > 1 file changed, 27 insertions(+), 27 deletions(-) >