From patchwork Thu Jan 11 07:24:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Beulich X-Patchwork-Id: 13516840 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8879FC47077 for ; Thu, 11 Jan 2024 07:24:26 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.665898.1036203 (Exim 4.92) (envelope-from ) id 1rNpQG-00020D-Ob; Thu, 11 Jan 2024 07:24:16 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 665898.1036203; Thu, 11 Jan 2024 07:24:16 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rNpQG-000206-Kt; Thu, 11 Jan 2024 07:24:16 +0000 Received: by outflank-mailman (input) for mailman id 665898; Thu, 11 Jan 2024 07:24:15 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rNpQF-000200-FB for xen-devel@lists.xenproject.org; Thu, 11 Jan 2024 07:24:15 +0000 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [2a00:1450:4864:20::42a]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 6abee138-b052-11ee-9b0f-b553b5be7939; Thu, 11 Jan 2024 08:24:12 +0100 (CET) Received: by mail-wr1-x42a.google.com with SMTP id ffacd0b85a97d-3376555b756so2871906f8f.0 for ; Wed, 10 Jan 2024 23:24:12 -0800 (PST) Received: from [10.156.60.236] (ip-037-024-206-209.um08.pools.vodafone-ip.de. [37.24.206.209]) by smtp.gmail.com with ESMTPSA id o10-20020a056000010a00b00336cbbf2e0fsm441141wrx.27.2024.01.10.23.24.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 10 Jan 2024 23:24:12 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 6abee138-b052-11ee-9b0f-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1704957852; x=1705562652; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:references:cc:to :from:content-language:subject:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to; bh=0ec8vWmu/5aIAhFU+GtuouuNHSKMP58o3QH8ANpxtGg=; b=ONNAVtEf07iJts9lW9wgn7Bpn1MQpPFQFiKdqFXYmRbbKXtV6uhSmx9oM4oS5+qVrZ 4xGG+IOnqb3+0EslsWnLAdOkH3P2IYkapwvOBLCktekSGoNYwHAdl/SSexNI6/fZ4Slj VuDoQLMsKdhcRhXJp7t/tEgRxFwHJvpl5yzj6addLE8yHI2pYBhB++PY1gq1eEelFynx Ye4kmIcR9nfOH8pp383PAGnDfa9TDCs1lddMrjLrrNmUcA9mjBceVivX5tLP2azl6Nrb H/mgRQ7rLMoFJueqBUs/j99RxbXBsTCU0hAGOcj3VpLLBOzn3rUACn5ULWMHTYHp8rk7 y/Bw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704957852; x=1705562652; h=content-transfer-encoding:in-reply-to:autocrypt:references:cc:to :from:content-language:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=0ec8vWmu/5aIAhFU+GtuouuNHSKMP58o3QH8ANpxtGg=; b=r9Ie8ogk8lQpoZ0fsjvPb1U7jBrSqWMDSz8bLtUFOeVBNk9RQjVOw+4larspBPoKA0 46kNQic/To5HuE237ODG/cNZuA8yP/WjX9tZdfwH11cJwC53ecwgwyYjzy4XK8CqNkgM Gz29fsA6NltPmGZcCkB+xcLLVF3AcC3c4A+O5iE6GqRMO00olAkfh++vOrLHzgvLA9zV 38Q607+DsoDCG+ehvOYaWp9+l4IuMbHWcZw57TEeQ3A3bnv7GtZMro+iC0GQj6cEzqCi 8l+MWBbd8pRYLQeYqXydBwsj+M6PRHbgblUFE9EJRRLBkzFEbD8J0lutQxSwBQTKrhXK Gg6Q== X-Gm-Message-State: AOJu0YwowPaTtfQ0+D99hAWnuXbSkOyNFX6/pBDKGEmUaYT5AxpT5ulH AuH1CvanfyIZTxmgdrJ1iglsRPOZjCaOcKe0x828DViALQ== X-Google-Smtp-Source: AGHT+IF1iJxaRdntkDF6jKFL3SB64XOqnl8kfYx8ByE0l/AFs6MuYV1rrBHuaqDcYD6+FxYvkPCG+Q== X-Received: by 2002:adf:9bc6:0:b0:337:7ac9:7920 with SMTP id e6-20020adf9bc6000000b003377ac97920mr158295wrc.22.1704957852399; Wed, 10 Jan 2024 23:24:12 -0800 (PST) Message-ID: <2b7dd916-9e5e-4226-94d5-5439d403644d@suse.com> Date: Thu, 11 Jan 2024 08:24:11 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH 1/8] limit passing around of cpu_user_regs Content-Language: en-US From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , George Dunlap , Julien Grall , Stefano Stabellini , Wei Liu References: <5d6089a4-c597-49ce-b042-24f13922f581@suse.com> Autocrypt: addr=jbeulich@suse.com; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL In-Reply-To: <5d6089a4-c597-49ce-b042-24f13922f581@suse.com> There are exactly two handlers which care about the registers. Have handle_keypress() make the pointer available via a per-CPU variable, thus eliminating the need to pass it to all IRQ key handlers, making sure that a console-invoked key's handling can still nest inside a sysctl-invoked one's. Signed-off-by: Jan Beulich --- Subsequently we may want to eliminate the fn/irq_fn union as well, along with dropping the now redundant irq_keyhandler_fn_t. --- a/xen/common/keyhandler.c +++ b/xen/common/keyhandler.c @@ -80,6 +80,7 @@ static void cf_check keypress_action(voi } static DECLARE_TASKLET(keypress_tasklet, keypress_action, NULL); +static DEFINE_PER_CPU(struct cpu_user_regs *, keypress_regs); void handle_keypress(unsigned char key, struct cpu_user_regs *regs) { @@ -91,7 +92,16 @@ void handle_keypress(unsigned char key, if ( !in_irq() || h->irq_callback ) { console_start_log_everything(); - h->irq_callback ? h->irq_fn(key, regs) : h->fn(key); + if ( h->irq_callback ) + { + struct cpu_user_regs *old = this_cpu(keypress_regs); + + this_cpu(keypress_regs) = regs; + h->irq_fn(key); + this_cpu(keypress_regs) = old; + } + else + h->fn(key); console_end_log_everything(); } else @@ -171,8 +181,7 @@ void cf_check dump_execstate(struct cpu_ watchdog_enable(); } -static void cf_check dump_registers( - unsigned char key, struct cpu_user_regs *regs) +static void cf_check dump_registers(unsigned char key) { unsigned int cpu; @@ -185,8 +194,8 @@ static void cf_check dump_registers( cpumask_copy(&dump_execstate_mask, &cpu_online_map); /* Get local execution state out immediately, in case we get stuck. */ - if ( regs ) - dump_execstate(regs); + if ( this_cpu(keypress_regs) ) + dump_execstate(this_cpu(keypress_regs)); else run_in_exception_handler(dump_execstate); @@ -248,8 +257,7 @@ static void cf_check dump_hwdom_register } } -static void cf_check reboot_machine( - unsigned char key, struct cpu_user_regs *regs) +static void cf_check reboot_machine(unsigned char key) { printk("'%c' pressed -> rebooting machine\n", key); machine_restart(0); @@ -477,8 +485,7 @@ static void cf_check run_all_nonirq_keyh static DECLARE_TASKLET(run_all_keyhandlers_tasklet, run_all_nonirq_keyhandlers, NULL); -static void cf_check run_all_keyhandlers( - unsigned char key, struct cpu_user_regs *regs) +static void cf_check run_all_keyhandlers(unsigned char key) { struct keyhandler *h; unsigned int k; @@ -494,7 +501,7 @@ static void cf_check run_all_keyhandlers if ( !h->irq_fn || !h->diagnostic || !h->irq_callback ) continue; printk("[%c: %s]\n", k, h->desc); - h->irq_fn(k, regs); + h->irq_fn(k); } watchdog_enable(); @@ -511,17 +518,16 @@ static void cf_check do_debugger_trap_fa barrier(); } -static void cf_check do_debug_key(unsigned char key, struct cpu_user_regs *regs) +static void cf_check do_debug_key(unsigned char key) { printk("'%c' pressed -> trapping into debugger\n", key); - if ( regs ) - do_debugger_trap_fatal(regs); + if ( this_cpu(keypress_regs) ) + do_debugger_trap_fatal(this_cpu(keypress_regs)); else run_in_exception_handler(do_debugger_trap_fatal); } -static void cf_check do_toggle_alt_key( - unsigned char key, struct cpu_user_regs *regs) +static void cf_check do_toggle_alt_key(unsigned char key) { alt_key_handling = !alt_key_handling; printk("'%c' pressed -> using %s key handling\n", key, --- a/xen/drivers/char/console.c +++ b/xen/drivers/char/console.c @@ -280,7 +280,7 @@ static int *__read_mostly upper_thresh_a static int *__read_mostly lower_thresh_adj = &xenlog_lower_thresh; static const char *__read_mostly thresh_adj = "standard"; -static void cf_check do_toggle_guest(unsigned char key, struct cpu_user_regs *regs) +static void cf_check do_toggle_guest(unsigned char key) { if ( upper_thresh_adj == &xenlog_upper_thresh ) { @@ -307,13 +307,13 @@ static void do_adj_thresh(unsigned char loglvl_str(*upper_thresh_adj)); } -static void cf_check do_inc_thresh(unsigned char key, struct cpu_user_regs *regs) +static void cf_check do_inc_thresh(unsigned char key) { ++*lower_thresh_adj; do_adj_thresh(key); } -static void cf_check do_dec_thresh(unsigned char key, struct cpu_user_regs *regs) +static void cf_check do_dec_thresh(unsigned char key) { if ( *lower_thresh_adj ) --*lower_thresh_adj; --- a/xen/include/xen/keyhandler.h +++ b/xen/include/xen/keyhandler.h @@ -24,9 +24,7 @@ typedef void (keyhandler_fn_t)(unsigned * * Called in hardirq context with interrupts disabled. */ -struct cpu_user_regs; -typedef void (irq_keyhandler_fn_t)(unsigned char key, - struct cpu_user_regs *regs); +typedef void irq_keyhandler_fn_t(unsigned char key); /* Initialize keytable with default handlers. */ void initialize_keytable(void); @@ -46,6 +44,7 @@ void register_irq_keyhandler(unsigned ch bool diagnostic); /* Inject a keypress into the key-handling subsystem. */ +struct cpu_user_regs; extern void handle_keypress(unsigned char key, struct cpu_user_regs *regs); enum crash_reason {