From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.218.41 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794508390; b=4zF7Yg4+cCTc2lbvUA4cPPyT6f+ZL1YxT4TCbzudbW6YtzpN5vFoh12NAM/hj2CPtan4 g+m/pTmvrfAvJbcheJoNhSL+4QyWBRnKqHD8ojmiZSczhy06JdyMfAHFypkOX2dXPCuHr pHLTev4Xdlbyq9ZHdSYM2d6UHwfk3/x2RdzYGcnlaZ0enHsPlZnY0pcfMrKiNvo2Nt3ND FlDKqv//9IEPcSrz/nijSJ1+0oO76q6GWShUIufC7wabO4Y567+Y13FvnTw1C0can906p ZVb/FvNnwe6PSpWBFRPuwwHOLO7octvet1W4IvCeMYVS9E/R7hj3OkEASATjUazCioA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794508390; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: From:X-Google-Original-From:Date:To:Cc:Subject:Message-ID:References: MIME-Version:Content-Type:Content-Disposition: Content-Transfer-Encoding:In-Reply-To; bh=7XTaMBSJocX7R1q9IiXe5TvK1ts0/2rtoQ55kCQz38Q=; b=pCckbRVOODN+pnAsqjvlZVFlwuqHnxuxV/8li6EaaPip5zVlEFIKWGv2zbwaTnibRvxH Ah81yBuVVigGeavRlNprzLnZsy9Q8H+UqwGNvdEJ5C3SCzoqEGdTzH+93/YZUi49JPcEn 23Hq7j52LApWZsfinw+8hbzrxIxes00JF0cMNSeQjMi1asBwgdKGqU8ZhpEIV/6DgRMi7 3HQb7TGwTzCJlsHlN8/7bhRogUuQRMsoCTCxhjrG7/GFkR14dl32ezEwBa8fI8qp2FT1F 0/FSEHyEcxaZR8gH+Lb9L2kcQPIsrJyIV35GQ//0f6TvrKiJA3FNig3yIMv7WyVj5nw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=L+hCYSRp; arc=none smtp.remote-ip=209.85.218.41 Received: from mail-ej1-f41.google.com (mail-ej1-f41.google.com [209.85.218.41]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8208B606A8BA for ; Thu, 12 Nov 2026 18:33:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 8208B606A8BA Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=L+hCYSRp Received: by mail-ej1-f41.google.com with SMTP id a640c23a62f3a-c50933bdf4bso31443766b.1 for ; Thu, 12 Nov 2026 10:33:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1794508389; x=1795113189; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:date :from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=7XTaMBSJocX7R1q9IiXe5TvK1ts0/2rtoQ55kCQz38Q=; b=L+hCYSRpqtbZvvzfTPM51bNUhMq2BbuykAG5oFAhxSmlmrzcY9wgwVFlr9REQwSZ3x wFQ6aD5XkVDSlS/t58e2UDg4YJLULKoeISY6s48Uc8/WoP71bu8tnqwwhKrweZaLpmyV dIFkAlIIk/2ibebZ6Clb/IQ1VW9uBuNzs3oRGC3Cy/4rIjM8ybiqZ+dPvrCsX7ObOkTu 3yV5Ycwm05puJ4S++T/NemezOeH+JiHw7TmJPBFnw7JNh6J4/wpJgrdWY4J5FQsB6Gkq ctxI8c7X7ypxK7cTPvieH4Y2A3rpTI2NqPrPISkBK53e2xSFbKFOl1D6Pa39J3FtUw6v egfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794508389; x=1795113189; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:date :from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=7XTaMBSJocX7R1q9IiXe5TvK1ts0/2rtoQ55kCQz38Q=; b=pEPiK50pYuotozYeOU0tQq97DHtoCsw7U58gRu7iOxjzCK9+lgcIKZ82TD/c7aOvoU +od72r+dz6d2xFyMzKxYScMsyj48tblFskDlHUpzCaHVL9N6o6rqaJLFRFeQlyMwrqyS VPbpMh4GfbLtzpwf+Gfys2R2pVSKD5nbGZ3QZ3FLbhK8+IKIToCBRx0PH5nti5bKSpct 6r9VrsJWTOGYJIu19Hw5kaYZLaA8Md3Pcj2w6W2a3c7kyQxlJ0r4OitZRLn2hi11F5vV wEe4C8dcigtHtVXi09CHiylNULZ/hIQCfUxgbF3K3SlZ+5VW5ROj60I0jtW0yAjX2vPe 2iug== X-Forwarded-Encrypted: i=1; AL+hErGfvq7IjvJD7x7TZUrSTq5AT2aEmCy93S27b7WBAoL6DaqQDry9z5txTwhnStef6fPBNh0LknwvUDmG4+g=@vger.kernel.org X-Gm-Message-State: APuU4Z+JUC90hBTTK7UVHOyqVITpbjzqJJfByIK2LoP79W2Sp3pMQP/5 p87gnesjjTxQBuaqF3CFbeXJuSzzBnmNA8oD7QKW4fF7Il7n9akAu5a7 X-Gm-Gg: AYBFou0sO+ILJBaHI60q34q5sJJ4JkswTe0k/Juam+eyUSeCpkuv1pWovv0Kyxmk3rl o48fwERVJcG5tgueqK20xRQGzBZ6qYeB380cINEnIaz7Z6xirUYiFZG8WSLBO7QpOvZtboc9mid COEL2Kv1akkO01ZnDq7AN4vh1hPI4Zk0LvxjB1BlPWXHLaGmgMVP2YjnPHAWUlJD4TAZIQqoq0A 2g7LBQafwTKyk99TspssRF4UpoxUy0zWsoLoYD45iCfyMKBsZi2PsNsh4UtjL7uZajVJFYLt8/t vInNwpTI4jLY97NFMqNdOXazXfbKk6k9QnAxBWlTr1oM1fW0djMSxrEu5bFhR7rkmyvzkwunudO sQBBsJOHdCR3Z32+thSwUtCKfiaXJtuZUzMnSYDp3hmZ3tKBvK1g1CrNRywf29+/Lq8SiNvwWHF O29lD8EZ4AHmWsh+r/daLsPzv8VKxHPOP/5pds1zkyE4qJIzY8n2tj2kM5dI4XC+Sep57jX6b7A MKxw7UK/NOewKg39/6hilPYM/BlKgTolTXqTPZlU7uhUtyOJLkR+wKo2sUjVQywHiX7351QqGyS V/jxj0YdWWjJ27A3EL8BQqb6OdNGlcY9YrcnEQ== X-Received: by 2002:a17:907:c0f:b0:c2e:2275:1168 with SMTP id a640c23a62f3a-c507c3fd35fmr333753066b.19.1794508388705; Thu, 12 Nov 2026 10:33:08 -0800 (PST) Received: from krava ([173.38.220.46]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-c5095b2369asm6139766b.25.2026.11.12.10.33.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Nov 2026 10:33:07 -0800 (PST) From: Jiri Olsa X-Google-Original-From: Jiri Olsa Date: Thu, 12 Nov 2026 19:33:03 +0100 To: Peter Zijlstra Cc: Masami Hiramatsu , Naveen N Rao , "David S. Miller" , Josh Poimboeuf , Jason Baron , Alice Ryhl , Steven Rostedt , Ard Biesheuvel , Thomas Gleixner , Ingo Molnar , Alan Maguire , x86@kernel.org, linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH 01/13] static_call: Index code text reservation lookups Message-ID: References: <20261109194916.1089703-1-jolsa@kernel.org> <20261109194916.1089703-2-jolsa@kernel.org> <20261112090734.GH2668804@noisy.programming.kicks-ass.net> <20261112101108.GE2669272@noisy.programming.kicks-ass.net> 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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20261112101108.GE2669272@noisy.programming.kicks-ass.net> On Thu, Nov 12, 2026 at 11:11:08AM +0100, Peter Zijlstra wrote: > On Thu, Nov 12, 2026 at 10:07:34AM +0100, Peter Zijlstra wrote: > > Looking at this in a little more detail; I'm confused. > > > > You're literally adding an index, so that you can find the > > static_call_size, while all you really need is static_call_addr(). > > /size/site/ obviously :-) > > > That is, you could have just created an array of relocated site->addr > > and sorted that, that would safe you a ton of indirection all around. > > > > That is: > > > > index->entries[i] = (long)static_call_addr(start + i) - (long)&index->entries[i]; > > Should be: > > index->entries[i] = (long)static_call_addr(start + i) - (long)index->entries; > > They have to all be relative to one location in order for sorting to > make sense. > > > That will make your lookup take at least half the amount of loads. hum, but we still need the site’s init flag for static_call_is_init I could store site pointer directly instead of the index and see how much faster it is > > > > > > Also, you really should support modules, there is no point being fast > > until you load a module. I had that, but decided to remove it because my follow up changes did not support modules as well.. I will include it jirka