Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751938AbYKPKma (ORCPT ); Sun, 16 Nov 2008 05:42:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752065AbYKPKmH (ORCPT ); Sun, 16 Nov 2008 05:42:07 -0500 Received: from E23SMTP01.au.ibm.com ([202.81.18.162]:40601 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752001AbYKPKmG (ORCPT ); Sun, 16 Nov 2008 05:42:06 -0500 From: "Aneesh Kumar K.V" To: rostedt@goodmis.org, mingo@elte.hu, akpm@linux-foundation.org, fweisbec@gmail.com Cc: linux-kernel@vger.kernel.org, "Aneesh Kumar K.V" Subject: [PATCH] ftrace: Add debug_dump trace to dump binary data from kernel to userspace Date: Sun, 16 Nov 2008 16:08:01 +0530 Message-Id: <1226831883-26362-4-git-send-email-aneesh.kumar@linux.vnet.ibm.com> X-Mailer: git-send-email 1.6.0.4.735.gea4f In-Reply-To: <1226831883-26362-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com> References: <1226831883-26362-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1226831883-26362-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1226831883-26362-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4679 Lines: 172 The trace add a new interface debug_dump() which can be used to dump binary data using ftrace framework. Use the dump mode of iterator by 'echo dump > iter_ctrl' to read the value in userspace Signed-off-by: Aneesh Kumar K.V --- include/linux/debug_dump.h | 10 ++++ kernel/trace/Kconfig | 6 ++ kernel/trace/Makefile | 1 + kernel/trace/trace_debugdump.c | 103 ++++++++++++++++++++++++++++++++++++++++ 4 files changed, 120 insertions(+), 0 deletions(-) diff --git a/include/linux/debug_dump.h b/include/linux/debug_dump.h new file mode 100644 index 0000000..2c1836d --- /dev/null +++ b/include/linux/debug_dump.h @@ -0,0 +1,10 @@ +#ifndef _LINUX_DEBUGDUMP_H +#define _LINUX_DEBUGDUMP_H +#include + +#ifdef CONFIG_DEBUG_DUMP +extern int debug_dump(void *p, int len); +#else +#define debug_dump(p, len) +#endif +#endif /* _LINUX_DEBUGDUMP_H */ diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 30eccc8..247cf3f 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -261,4 +261,10 @@ config DEBUG_PRINT help This tracer can be used for printk style debugging. +config DEBUG_DUMP + bool "Trace based dump support" + depends on DEBUG_KERNEL + select TRACING + help + This tracer can be used to dump binary data from kernel endmenu diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 86e5869..b1c6dec 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -32,5 +32,6 @@ obj-$(CONFIG_BOOT_TRACER) += trace_boot.o obj-$(CONFIG_FUNCTION_RET_TRACER) += trace_functions_return.o obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o obj-$(CONFIG_DEBUG_PRINT) += trace_debugprint.o +obj-$(CONFIG_DEBUG_DUMP) += trace_debugdump.o libftrace-y := ftrace.o diff --git a/kernel/trace/trace_debugdump.c b/kernel/trace/trace_debugdump.c new file mode 100644 index 0000000..3ebae2a --- /dev/null +++ b/kernel/trace/trace_debugdump.c @@ -0,0 +1,103 @@ +/* + * Copyright IBM Corporation, 2008 + * Author Aneesh Kumar K.V + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2.1 of the GNU Lesser General Public License + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + */ + +#include +#include +#include +#include + +#include "trace.h" + +static struct trace_array *ctx_trace; +static int __read_mostly dd_tracer_enabled; + +int debug_dump(void *bin_data, int len) +{ + int size; + unsigned long irq_flags; + struct dump_entry *entry; + struct ring_buffer_event *event; + + if (!dd_tracer_enabled) + return 0; + + size = sizeof(*entry) + len; + event = ring_buffer_lock_reserve(ctx_trace->buffer, size, &irq_flags); + if (!event) + return 0; + entry = ring_buffer_event_data(event); + tracing_generic_entry_update(&entry->ent, 0, preempt_count()); + entry->ent.type = TRACE_BIN_DUMP; + entry->len = len; + + memcpy(&entry->buf, bin_data, len); + ring_buffer_unlock_commit(ctx_trace->buffer, event, irq_flags); + + return len; +} +EXPORT_SYMBOL_GPL(debug_dump); + +static void dd_reset(struct trace_array *tr) +{ + int cpu; + + tr->time_start = ftrace_now(tr->cpu); + + for_each_online_cpu(cpu) + tracing_reset(tr, cpu); +} + +static void dd_trace_start(struct trace_array *tr) +{ + dd_reset(tr); + dd_tracer_enabled = 1; +} + +static void dd_trace_stop(struct trace_array *tr) +{ + dd_tracer_enabled = 0; + /* Nothing to do! */ +} + +static void dd_trace_init(struct trace_array *tr) +{ + ctx_trace = tr; + /* + * enable the trace during init if + * we have enabled flag already set + */ + if (tracing_is_enabled()) + dd_trace_start(tr); +} + +static void dd_trace_reset(struct trace_array *tr) +{ + if (dd_tracer_enabled) + dd_trace_stop(tr); +} + +struct tracer dd_trace __read_mostly = +{ + .name = "debug_dump", + .init = dd_trace_init, + .reset = dd_trace_reset, + .start = dd_trace_start, + .stop = dd_trace_stop, +}; + +__init static int init_dd_trace(void) +{ + return register_tracer(&dd_trace); +} +device_initcall(init_dd_trace); -- tg: (140170e..) an/ftrace-debug-dump.patch (depends on: an/ftrace-bin-dump.patch) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/