From patchwork Wed Jan 11 14:56:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13096831 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2974FC46467 for ; Wed, 11 Jan 2023 14:59:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231420AbjAKO7F (ORCPT ); Wed, 11 Jan 2023 09:59:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239533AbjAKO6r (ORCPT ); Wed, 11 Jan 2023 09:58:47 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20396A44F; Wed, 11 Jan 2023 06:58:46 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D050DB81C0F; Wed, 11 Jan 2023 14:58:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 889CDC433D2; Wed, 11 Jan 2023 14:58:43 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1pFcYs-000M7B-1e; Wed, 11 Jan 2023 09:58:42 -0500 Message-ID: <20230111145842.376427803@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 11 Jan 2023 09:56:37 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , Ross Zwisler Subject: [PATCH 1/4] tracing: Add creation of instances at boot command line References: <20230111145636.450953217@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: "Steven Rostedt (Google)" Add kernel command line to add tracing instances. This only creates instances at boot but still does not enable any events to them. Later changes will extend this command line to add enabling of events, filters, and triggers. As well as possibly redirecting trace_printk()! Signed-off-by: Steven Rostedt (Google) Reviewed-by: Ross Zwisler --- .../admin-guide/kernel-parameters.txt | 6 +++ kernel/trace/trace.c | 51 +++++++++++++++++++ 2 files changed, 57 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6cfa6e3996cf..cec486217ccc 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6272,6 +6272,12 @@ comma-separated list of trace events to enable. See also Documentation/trace/events.rst + trace_instance=[instance-info] + [FTRACE] Create an ring buffer instance early in boot up. + This will be listed in: + + /sys/kernel/tracing/instances + trace_options=[option-list] [FTRACE] Enable or disable tracer options at boot. The option-list is a comma delimited list of options diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a555a861b978..34ed504ffca9 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -48,6 +48,9 @@ #include #include #include +#include + +#include /* COMMAND_LINE_SIZE */ #include "trace.h" #include "trace_output.h" @@ -186,6 +189,9 @@ static char *default_bootup_tracer; static bool allocate_snapshot; static bool snapshot_at_boot; +static char boot_instance_info[COMMAND_LINE_SIZE] __initdata; +static int boot_instance_index; + static int __init set_cmdline_ftrace(char *str) { strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); @@ -239,6 +245,23 @@ static int __init boot_snapshot(char *str) __setup("ftrace_boot_snapshot", boot_snapshot); +static int __init boot_instance(char *str) +{ + char *slot = boot_instance_info + boot_instance_index; + int left = COMMAND_LINE_SIZE - boot_instance_index; + int ret; + + if (strlen(str) >= left) + return -1; + + ret = snprintf(slot, left, "%s\t", str); + boot_instance_index += ret; + + return 1; +} +__setup("trace_instance=", boot_instance); + + static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; static int __init set_trace_boot_options(char *str) @@ -10144,6 +10167,31 @@ ssize_t trace_parse_run_command(struct file *file, const char __user *buffer, return ret; } +__init static void enable_instances(void) +{ + struct trace_array *tr; + char *curr_str; + char *str; + char *tok; + + /* A tab is always appended */ + boot_instance_info[boot_instance_index - 1] = '\0'; + str = boot_instance_info; + + while ((curr_str = strsep(&str, "\t"))) { + + tok = strsep(&curr_str, ","); + + tr = trace_array_get_by_name(tok); + if (!tr) { + pr_warn("Failed to create instance buffer %s\n", curr_str); + continue; + } + /* Allow user space to delete it */ + trace_array_put(tr); + } +} + __init static int tracer_alloc_buffers(void) { int ring_buf_size; @@ -10300,6 +10348,9 @@ void __init early_trace_init(void) void __init trace_init(void) { trace_event_init(); + + if (boot_instance_index) + enable_instances(); } __init static void clear_boot_tracer(void) From patchwork Wed Jan 11 14:56:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13096832 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83259C5479D for ; Wed, 11 Jan 2023 14:59:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232339AbjAKO7G (ORCPT ); Wed, 11 Jan 2023 09:59:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239512AbjAKO6q (ORCPT ); Wed, 11 Jan 2023 09:58:46 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA7356328; Wed, 11 Jan 2023 06:58:44 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3FC3361D4F; Wed, 11 Jan 2023 14:58:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4CBCC43392; Wed, 11 Jan 2023 14:58:43 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1pFcYs-000M7f-2A; Wed, 11 Jan 2023 09:58:42 -0500 Message-ID: <20230111145842.534011158@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 11 Jan 2023 09:56:38 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , Ross Zwisler Subject: [PATCH 2/4] tracing: Add enabling of events to boot instances References: <20230111145636.450953217@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: "Steven Rostedt (Google)" Add the format of: trace_instance=foo,sched:sched_switch,irq_handler_entry,initcall That will create the "foo" instance and enable the sched_switch event (here were the "sched" system is explicitly specified), the irq_handler_entry event, and all events under the system initcall. Signed-off-by: Steven Rostedt (Google) Reviewed-by: Ross Zwisler --- Documentation/admin-guide/kernel-parameters.txt | 14 ++++++++++++++ kernel/trace/trace.c | 4 ++++ kernel/trace/trace.h | 2 ++ kernel/trace/trace_events.c | 9 ++++----- 4 files changed, 24 insertions(+), 5 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index cec486217ccc..7a7f41652719 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6278,6 +6278,20 @@ /sys/kernel/tracing/instances + Events can be enabled at the time the instance is created + via: + + trace_instance=,:,: + + Note, the ":" portion is optional if the event is + unique. + + trace_instance=foo,sched:sched_switch,irq_handler_entry,initcall + + will enable the "sched_switch" event (note, the "sched:" is optional, and + the same thing would happen if it was left off). The irq_handler_entry + event, and all events under the "initcall" system. + trace_options=[option-list] [FTRACE] Enable or disable tracer options at boot. The option-list is a comma delimited list of options diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 34ed504ffca9..e8c52a8d712e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -10189,6 +10189,10 @@ __init static void enable_instances(void) } /* Allow user space to delete it */ trace_array_put(tr); + + while ((tok = strsep(&curr_str, ","))) { + early_enable_events(tr, tok, true); + } } } diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index e46a49269be2..a56b0b7d23ef 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1330,6 +1330,8 @@ DECLARE_PER_CPU(int, trace_buffered_event_cnt); void trace_buffered_event_disable(void); void trace_buffered_event_enable(void); +void early_enable_events(struct trace_array *tr, char *buf, bool disable_first); + static inline void __trace_event_discard_commit(struct trace_buffer *buffer, struct ring_buffer_event *event) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index b07931ad97de..cf3fd74fa675 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -3750,10 +3750,9 @@ static __init int event_trace_memsetup(void) return 0; } -static __init void -early_enable_events(struct trace_array *tr, bool disable_first) +__init void +early_enable_events(struct trace_array *tr, char *buf, bool disable_first) { - char *buf = bootup_event_buf; char *token; int ret; @@ -3806,7 +3805,7 @@ static __init int event_trace_enable(void) */ __trace_early_add_events(tr); - early_enable_events(tr, false); + early_enable_events(tr, bootup_event_buf, false); trace_printk_start_comm(); @@ -3834,7 +3833,7 @@ static __init int event_trace_enable_again(void) if (!tr) return -ENODEV; - early_enable_events(tr, true); + early_enable_events(tr, bootup_event_buf, true); return 0; } From patchwork Wed Jan 11 14:56:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13096833 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6004C54EBC for ; Wed, 11 Jan 2023 14:59:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232621AbjAKO7H (ORCPT ); Wed, 11 Jan 2023 09:59:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239532AbjAKO6r (ORCPT ); Wed, 11 Jan 2023 09:58:47 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 636B9D4A; Wed, 11 Jan 2023 06:58:46 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1D181B81C11; Wed, 11 Jan 2023 14:58:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCFC4C43398; Wed, 11 Jan 2023 14:58:43 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1pFcYs-000M89-2f; Wed, 11 Jan 2023 09:58:42 -0500 Message-ID: <20230111145842.694147820@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 11 Jan 2023 09:56:39 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , Ross Zwisler Subject: [PATCH 3/4] tracing: Add trace_array_puts() to write into instance References: <20230111145636.450953217@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: "Steven Rostedt (Google)" Add a generic trace_array_puts() that can be used to "trace_puts()" into an allocated trace_array instance. This is just another variant of trace_array_printk(). Signed-off-by: Steven Rostedt (Google) Reviewed-by: Ross Zwisler --- include/linux/trace.h | 13 +++++++++++++ kernel/trace/trace.c | 27 +++++++++++++++++---------- 2 files changed, 30 insertions(+), 10 deletions(-) diff --git a/include/linux/trace.h b/include/linux/trace.h index 80ffda871749..afe61949e83a 100644 --- a/include/linux/trace.h +++ b/include/linux/trace.h @@ -33,6 +33,19 @@ struct trace_array; int register_ftrace_export(struct trace_export *export); int unregister_ftrace_export(struct trace_export *export); +/** + * trace_array_puts - write a constant string into the trace buffer. + * @tr: The trace array to write to + * @ip: The address of the caller + * @str: The constant string to write + */ +#define trace_array_puts(tr, str) \ + ({ \ + str ? __trace_array_puts(tr, _THIS_IP_, str, strlen(str)) : -1; \ + }) +int __trace_array_puts(struct trace_array *tr, unsigned long ip, + const char *str, int size); + void trace_printk_init_buffers(void); __printf(3, 4) int trace_array_printk(struct trace_array *tr, unsigned long ip, diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index e8c52a8d712e..3cb9bbc0f076 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1024,13 +1024,8 @@ __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *ev ring_buffer_unlock_commit(buffer); } -/** - * __trace_puts - write a constant string into the trace buffer. - * @ip: The address of the caller - * @str: The constant string to write - * @size: The size of the string. - */ -int __trace_puts(unsigned long ip, const char *str, int size) +int __trace_array_puts(struct trace_array *tr, unsigned long ip, + const char *str, int size) { struct ring_buffer_event *event; struct trace_buffer *buffer; @@ -1038,7 +1033,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) unsigned int trace_ctx; int alloc; - if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) + if (!(tr->trace_flags & TRACE_ITER_PRINTK)) return 0; if (unlikely(tracing_selftest_running || tracing_disabled)) @@ -1047,7 +1042,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) alloc = sizeof(*entry) + size + 2; /* possible \n added */ trace_ctx = tracing_gen_ctx(); - buffer = global_trace.array_buffer.buffer; + buffer = tr->array_buffer.buffer; ring_buffer_nest_start(buffer); event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, trace_ctx); @@ -1069,11 +1064,23 @@ int __trace_puts(unsigned long ip, const char *str, int size) entry->buf[size] = '\0'; __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL); + ftrace_trace_stack(tr, buffer, trace_ctx, 4, NULL); out: ring_buffer_nest_end(buffer); return size; } +EXPORT_SYMBOL_GPL(__trace_array_puts); + +/** + * __trace_puts - write a constant string into the trace buffer. + * @ip: The address of the caller + * @str: The constant string to write + * @size: The size of the string. + */ +int __trace_puts(unsigned long ip, const char *str, int size) +{ + return __trace_array_puts(&global_trace, ip, str, size); +} EXPORT_SYMBOL_GPL(__trace_puts); /** From patchwork Wed Jan 11 14:56:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13096830 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D202C5479D for ; Wed, 11 Jan 2023 14:59:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229737AbjAKO7F (ORCPT ); Wed, 11 Jan 2023 09:59:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239513AbjAKO6q (ORCPT ); Wed, 11 Jan 2023 09:58:46 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06CF663C6; Wed, 11 Jan 2023 06:58:45 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 95C7E61D52; Wed, 11 Jan 2023 14:58:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 02AD3C433F2; Wed, 11 Jan 2023 14:58:44 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1pFcYs-000M8d-3B; Wed, 11 Jan 2023 09:58:42 -0500 Message-ID: <20230111145842.847715402@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 11 Jan 2023 09:56:40 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , Ross Zwisler Subject: [PATCH 4/4] tracing: Allow boot instances to have snapshot buffers References: <20230111145636.450953217@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: "Steven Rostedt (Google)" Add to ftrace_boot_snapshot, "=" name, where the instance will get a snapshot buffer, and will take a snapshot at the end of boot (which will save the boot traces). Signed-off-by: Steven Rostedt (Google) Reviewed-by: Ross Zwisler --- .../admin-guide/kernel-parameters.txt | 9 +++ kernel/trace/trace.c | 77 +++++++++++++++++-- 2 files changed, 79 insertions(+), 7 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 7a7f41652719..f4e87b17427f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1532,6 +1532,15 @@ boot up that is likely to be overridden by user space start up functionality. + Optionally, the snapshot can also be defined for a tracing + instance that was created by the trace_instance= command + line parameter. + + trace_instance=foo,sched_switch ftrace_boot_snapshot=foo + + The above will cause the "foo" tracing instance to trigger + a snapshot at the end of boot up. + ftrace_dump_on_oops[=orig_cpu] [FTRACE] will dump the trace buffers on oops. If no parameter is passed, ftrace will dump diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 3cb9bbc0f076..d445789dc247 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -192,6 +192,9 @@ static bool snapshot_at_boot; static char boot_instance_info[COMMAND_LINE_SIZE] __initdata; static int boot_instance_index; +static char boot_snapshot_info[COMMAND_LINE_SIZE] __initdata; +static int boot_snapshot_index; + static int __init set_cmdline_ftrace(char *str) { strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); @@ -228,9 +231,22 @@ __setup("traceoff_on_warning", stop_trace_on_warning); static int __init boot_alloc_snapshot(char *str) { - allocate_snapshot = true; - /* We also need the main ring buffer expanded */ - ring_buffer_expanded = true; + char *slot = boot_snapshot_info + boot_snapshot_index; + int left = COMMAND_LINE_SIZE - boot_snapshot_index; + int ret; + + if (str[0] == '=') { + str++; + if (strlen(str) >= left) + return -1; + + ret = snprintf(slot, left, "%s\t", str); + boot_snapshot_index += ret; + } else { + allocate_snapshot = true; + /* We also need the main ring buffer expanded */ + ring_buffer_expanded = true; + } return 1; } __setup("alloc_snapshot", boot_alloc_snapshot); @@ -9255,10 +9271,6 @@ static int allocate_trace_buffers(struct trace_array *tr, int size) } tr->allocated_snapshot = allocate_snapshot; - /* - * Only the top level trace array gets its snapshot allocated - * from the kernel command line. - */ allocate_snapshot = false; #endif @@ -10174,6 +10186,45 @@ ssize_t trace_parse_run_command(struct file *file, const char __user *buffer, return ret; } +#ifdef CONFIG_TRACER_MAX_TRACE +__init static bool tr_needs_alloc_snapshot(const char *name) +{ + char *test; + int len = strlen(name); + bool ret; + + if (!boot_snapshot_index) + return false; + + if (strncmp(name, boot_snapshot_info, len) == 0 && + boot_snapshot_info[len] == '\t') + return true; + + test = kmalloc(strlen(name) + 3, GFP_KERNEL); + if (!test) + return false; + + sprintf(test, "\t%s\t", name); + ret = strstr(boot_snapshot_info, test) == 0; + kfree(test); + return ret; +} + +__init static void do_allocate_snapshot(const char *name) +{ + if (!tr_needs_alloc_snapshot(name)) + return; + + /* + * When allocate_snapshot is set, the next call to + * allocate_trace_buffers() (called by trace_array_get_by_name()) + * will allocate the snapshot buffer. That will alse clear + * this flag. + */ + allocate_snapshot = true; +} +#endif + __init static void enable_instances(void) { struct trace_array *tr; @@ -10189,6 +10240,9 @@ __init static void enable_instances(void) tok = strsep(&curr_str, ","); + if (IS_ENABLED(CONFIG_TRACER_MAX_TRACE)) + do_allocate_snapshot(tok); + tr = trace_array_get_by_name(tok); if (!tr) { pr_warn("Failed to create instance buffer %s\n", curr_str); @@ -10336,10 +10390,19 @@ __init static int tracer_alloc_buffers(void) void __init ftrace_boot_snapshot(void) { + struct trace_array *tr; + if (snapshot_at_boot) { tracing_snapshot(); internal_trace_puts("** Boot snapshot taken **\n"); } + + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr == &global_trace) + continue; + trace_array_puts(tr, "** Boot snapshot taken **\n"); + tracing_snapshot_instance(tr); + } } void __init early_trace_init(void)