From patchwork Fri Jun 15 17:08:31 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Vorontsov X-Patchwork-Id: 9327 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 186F723E5A for ; Fri, 15 Jun 2012 17:10:58 +0000 (UTC) Received: from mail-gg0-f180.google.com (mail-gg0-f180.google.com [209.85.161.180]) by fiordland.canonical.com (Postfix) with ESMTP id C09D5A18491 for ; Fri, 15 Jun 2012 17:10:57 +0000 (UTC) Received: by ggnf1 with SMTP id f1so2743692ggn.11 for ; Fri, 15 Jun 2012 10:10:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-forwarded-to:x-forwarded-for:delivered-to:received-spf:from:to:cc :subject:date:message-id:x-mailer:in-reply-to:references :x-gm-message-state; bh=rBLwUjej70m+G4YML61t/5VBOABHOBvkirB1DdndAwQ=; b=PrNA0XJkncFzjUnS+3zkBVegQfUTZ/04X0QQ5w/pQrCAkCawr3bY8P2RLiEHaa/Ijr LNkV0jmbvXyFaTBhxHBlAUuI4qWERCUFOipT6zEYKsMGNt7b4h+SClMrcoxk4UJemegR jy6tAkCFCjWami+DYpbJW3vaHml6uMxYWw6IBILmE2DJHrSY0SEiB1x09uFCevZv0t5L Z8UZSmH3HU8aMF1ZuYQOoJMrcL5gVxOMLYmQxhJCGjWz35KwkGqJaaANv0xjWNJ3Wpig sM2osc8+V041713w36Auh7Gs7DArUrpFjSGTHa0ZDfCjiVUDSnpNdMaa4zZnXsdwVgbN k1WQ== Received: by 10.50.57.167 with SMTP id j7mr2731295igq.53.1339780257040; Fri, 15 Jun 2012 10:10:57 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.231.24.148 with SMTP id v20csp158967ibb; Fri, 15 Jun 2012 10:10:56 -0700 (PDT) Received: by 10.68.238.68 with SMTP id vi4mr21394781pbc.123.1339780256216; Fri, 15 Jun 2012 10:10:56 -0700 (PDT) Received: from mail-pb0-f50.google.com (mail-pb0-f50.google.com [209.85.160.50]) by mx.google.com with ESMTPS id gg3si6714088pbc.49.2012.06.15.10.10.56 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 15 Jun 2012 10:10:56 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.160.50 is neither permitted nor denied by best guess record for domain of anton.vorontsov@linaro.org) client-ip=209.85.160.50; Authentication-Results: mx.google.com; spf=neutral (google.com: 209.85.160.50 is neither permitted nor denied by best guess record for domain of anton.vorontsov@linaro.org) smtp.mail=anton.vorontsov@linaro.org Received: by mail-pb0-f50.google.com with SMTP id rr4so6362707pbb.37 for ; Fri, 15 Jun 2012 10:10:56 -0700 (PDT) Received: by 10.68.200.102 with SMTP id jr6mr22229405pbc.0.1339780255892; Fri, 15 Jun 2012 10:10:55 -0700 (PDT) Received: from localhost (c-71-204-165-222.hsd1.ca.comcast.net. [71.204.165.222]) by mx.google.com with ESMTPS id wi8sm13829634pbc.11.2012.06.15.10.10.53 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 15 Jun 2012 10:10:54 -0700 (PDT) From: Anton Vorontsov To: Greg Kroah-Hartman , Kees Cook , Colin Cross , Tony Luck , Steven Rostedt , Frederic Weisbecker , Ingo Molnar Cc: Arnd Bergmann , John Stultz , Shuah Khan , arve@android.com, Rebecca Schultz Zavin , Jesper Juhl , Randy Dunlap , Stephen Boyd , Thomas Meyer , Andrew Morton , Marco Stornelli , WANG Cong , linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org, linaro-kernel@lists.linaro.org, patches@linaro.org, kernel-team@android.com Subject: [PATCH 6/6] pstore/ram: Add ftrace messages handling Date: Fri, 15 Jun 2012 10:08:31 -0700 Message-Id: <1339780111-12075-6-git-send-email-anton.vorontsov@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <20120615170659.GA4060@lizard> References: <20120615170659.GA4060@lizard> X-Gm-Message-State: ALoCoQls+2+3VIqfXvpBtTnylMIjDWACmKh+4cyFLg/5ovvjJe283kSPqhKCTJ8wvgqxeWI30ead The ftrace log size is configurable via ramoops.ftrace_size module option, and the log itself is available via /ftrace-ramoops file. Signed-off-by: Anton Vorontsov --- Documentation/ramoops.txt | 25 +++++++++++++++++++++++++ fs/pstore/ram.c | 37 +++++++++++++++++++++++++++++++++---- include/linux/pstore_ram.h | 1 + 3 files changed, 59 insertions(+), 4 deletions(-) diff --git a/Documentation/ramoops.txt b/Documentation/ramoops.txt index 59a74a8..197ad59 100644 --- a/Documentation/ramoops.txt +++ b/Documentation/ramoops.txt @@ -94,3 +94,28 @@ timestamp and a new line. The dump then continues with the actual data. The dump data can be read from the pstore filesystem. The format for these files is "dmesg-ramoops-N", where N is the record number in memory. To delete a stored record from RAM, simply unlink the respective pstore file. + +5. Persistent function tracing + +Persistent function tracing might be useful for debugging software or hardware +related hangs. The functions call chain log is stored in a "ftrace-ramoops" +file. Here is an example of usage: + + # mount -t debugfs debugfs /sys/kernel/debug/ + # cd /sys/kernel/debug/tracing + # echo function > current_tracer + # echo 1 > options/func_pstore + # reboot -f + [...] + # mount -t pstore pstore /mnt/ + # tail /mnt/ftrace-ramoops + 0 ffffffff8101ea64 ffffffff8101bcda native_apic_mem_read <- disconnect_bsp_APIC+0x6a/0xc0 + 0 ffffffff8101ea44 ffffffff8101bcf6 native_apic_mem_write <- disconnect_bsp_APIC+0x86/0xc0 + 0 ffffffff81020084 ffffffff8101a4b5 hpet_disable <- native_machine_shutdown+0x75/0x90 + 0 ffffffff81005f94 ffffffff8101a4bb iommu_shutdown_noop <- native_machine_shutdown+0x7b/0x90 + 0 ffffffff8101a6a1 ffffffff8101a437 native_machine_emergency_restart <- native_machine_restart+0x37/0x40 + 0 ffffffff811f9876 ffffffff8101a73a acpi_reboot <- native_machine_emergency_restart+0xaa/0x1e0 + 0 ffffffff8101a514 ffffffff8101a772 mach_reboot_fixups <- native_machine_emergency_restart+0xe2/0x1e0 + 0 ffffffff811d9c54 ffffffff8101a7a0 __const_udelay <- native_machine_emergency_restart+0x110/0x1e0 + 0 ffffffff811d9c34 ffffffff811d9c80 __delay <- __const_udelay+0x30/0x40 + 0 ffffffff811d9d14 ffffffff811d9c3f delay_tsc <- __delay+0xf/0x20 diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 96dbd1e..018d895 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -45,6 +45,10 @@ static ulong ramoops_console_size = MIN_MEM_SIZE; module_param_named(console_size, ramoops_console_size, ulong, 0400); MODULE_PARM_DESC(console_size, "size of kernel console log"); +static ulong ramoops_ftrace_size = MIN_MEM_SIZE; +module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400); +MODULE_PARM_DESC(ftrace_size, "size of ftrace log"); + static ulong mem_address; module_param(mem_address, ulong, 0400); MODULE_PARM_DESC(mem_address, @@ -68,16 +72,19 @@ MODULE_PARM_DESC(ramoops_ecc, struct ramoops_context { struct persistent_ram_zone **przs; struct persistent_ram_zone *cprz; + struct persistent_ram_zone *fprz; phys_addr_t phys_addr; unsigned long size; size_t record_size; size_t console_size; + size_t ftrace_size; int dump_oops; bool ecc; unsigned int max_dump_cnt; unsigned int dump_write_cnt; unsigned int dump_read_cnt; unsigned int console_read_cnt; + unsigned int ftrace_read_cnt; struct pstore_info pstore; }; @@ -136,6 +143,9 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt, 1, id, type, PSTORE_TYPE_CONSOLE, 0); if (!prz) + prz = ramoops_get_next_prz(&cxt->fprz, &cxt->ftrace_read_cnt, + 1, id, type, PSTORE_TYPE_FTRACE, 0); + if (!prz) return 0; /* TODO(kees): Bogus time for the moment. */ @@ -184,6 +194,11 @@ static int ramoops_pstore_write_buf(enum pstore_type_id type, return -ENOMEM; persistent_ram_write(cxt->cprz, buf, size); return 0; + } else if (type == PSTORE_TYPE_FTRACE) { + if (!cxt->fprz) + return -ENOMEM; + persistent_ram_write(cxt->fprz, buf, size); + return 0; } if (type != PSTORE_TYPE_DMESG) @@ -233,6 +248,9 @@ static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, case PSTORE_TYPE_CONSOLE: prz = cxt->cprz; break; + case PSTORE_TYPE_FTRACE: + prz = cxt->fprz; + break; default: return -EINVAL; } @@ -346,7 +364,8 @@ static int __init ramoops_probe(struct platform_device *pdev) if (cxt->max_dump_cnt) goto fail_out; - if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size)) { + if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size && + !pdata->ftrace_size)) { pr_err("The memory size and the record/console size must be " "non-zero\n"); goto fail_out; @@ -355,18 +374,20 @@ static int __init ramoops_probe(struct platform_device *pdev) pdata->mem_size = rounddown_pow_of_two(pdata->mem_size); pdata->record_size = rounddown_pow_of_two(pdata->record_size); pdata->console_size = rounddown_pow_of_two(pdata->console_size); + pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size); cxt->dump_read_cnt = 0; cxt->size = pdata->mem_size; cxt->phys_addr = pdata->mem_address; cxt->record_size = pdata->record_size; cxt->console_size = pdata->console_size; + cxt->ftrace_size = pdata->ftrace_size; cxt->dump_oops = pdata->dump_oops; cxt->ecc = pdata->ecc; paddr = cxt->phys_addr; - dump_mem_sz = cxt->size - cxt->console_size; + dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size; err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz); if (err) goto fail_out; @@ -375,9 +396,14 @@ static int __init ramoops_probe(struct platform_device *pdev) if (err) goto fail_init_cprz; - if (!cxt->przs && !cxt->cprz) { + err = ramoops_init_prz(dev, cxt, &cxt->fprz, &paddr, cxt->ftrace_size); + if (err) + goto fail_init_fprz; + + if (!cxt->przs && !cxt->cprz && !cxt->fprz) { pr_err("memory size too small, minimum is %lu\n", - cxt->console_size + cxt->record_size); + cxt->console_size + cxt->record_size + + cxt->ftrace_size); goto fail_cnt; } @@ -424,6 +450,8 @@ fail_clear: cxt->pstore.bufsize = 0; cxt->max_dump_cnt = 0; fail_cnt: + kfree(cxt->fprz); +fail_init_fprz: kfree(cxt->cprz); fail_init_cprz: ramoops_free_przs(cxt); @@ -478,6 +506,7 @@ static int __init ramoops_init(void) dummy_data->mem_address = mem_address; dummy_data->record_size = record_size; dummy_data->console_size = ramoops_console_size; + dummy_data->ftrace_size = ramoops_ftrace_size; dummy_data->dump_oops = dump_oops; dummy_data->ecc = ramoops_ecc; dummy = platform_create_bundle(&ramoops_driver, ramoops_probe, diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h index 2470bb5..368da13 100644 --- a/include/linux/pstore_ram.h +++ b/include/linux/pstore_ram.h @@ -75,6 +75,7 @@ struct ramoops_platform_data { unsigned long mem_address; unsigned long record_size; unsigned long console_size; + unsigned long ftrace_size; int dump_oops; bool ecc; };