From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D0DEB3DC4C9 for ; Fri, 16 Oct 2026 14:31:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792161098; cv=none; b=hPhpTVYsFlVqek9u/tU4YqE6HycrTS5yFZJL/BTsHFjL6jTUqmk644xt9zCDYGYwYOTYyj8k/JsMKkvPaaSV3rSMpEFpLJE6+7lWbUyHbFrHkLeM6DBfSBfOXb92Zj1G6WPZklbwDuRQ74VAFdUm5gGs2gHhfZW/+5dbgfQP42c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792161098; c=relaxed/simple; bh=D4zlrXtVNFMr/YsUek1WgjTXQkTpGsROBWOh3llKygs=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=qf3bZRVCKSIWeitOoJqJ4Dl1r0hrbXaWGJ+H3aBDCuZI1J8Epykv1rdfGuu8mhMZ+lP+xgzC49AZyxDnysmBkqbUkTdbOQnizmrGORmKFhcqYN31/VZ+8NLZ9cCzmVhTqHSdNNcEwzf+Js1eWhpuwgZWu7vb4SY0ZSiCMhgW2eI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P75qDCT3; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="P75qDCT3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8F0371F000C4; Fri, 16 Oct 2026 14:31:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792161096; bh=SCdZHgy7aWsLgxdoxKhbflfwWJoHTNdJKjySNQD9uFk=; h=Date:From:To:Cc:Subject:References; b=P75qDCT3OxELmJHU0XtgVZSdVzCEgaYxgiR9mnDlU/PjdkUaTr+1i35gjcFiWYVoC W0/e4lBfPwKyrKM0GDYK1+8k0hjZQ8tSr/3KAcY6mtqodY0h0/KeUvUmjLqd+ZnqTI WeqDY0SMlHx2XY6coZ9ndneB0FElNYgMXmhWFF1JvJ02FgIesEN2/4vVIfEW0w930q uqSOJN4OASLF5WkD2xWYQDzmjs2UBeQ28U3/TjPMMIlYneyErli5dL852JPr+VfJWZ H/LgsqeftlhhA27O1+K/EU55DKnnWIQSfML8RrxkQ298aKU6kl77ZuuOan7p9MvOZa A6PnoD5EiWlew== Received: from rostedt by gandalf with local (Exim 4.100.1) (envelope-from ) id 1xHiy7-00000000Xkq-3pAn; Fri, 16 Oct 2026 10:31:35 -0400 Message-ID: <20261016143135.724893325@kernel.org> User-Agent: quilt/0.69 Date: Fri, 16 Oct 2026 10:31:23 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Subject: [for-next][PATCH 08/18] tracing: Parse filter from boot event string References: <20261016143115.392980228@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Make it possible to specify a trace event filter from the kernel command line. Example: trace_event=syscalls:sys_enter_clock_nanosleep:filter:which_clock==0 Link: https://patch.msgid.link/20260908-tracing-cli-event-filter-v2-7-05396a3fb663@linutronix.de Signed-off-by: Thomas Weißschuh Signed-off-by: Steven Rostedt --- .../admin-guide/kernel-parameters.txt | 9 +++++-- Documentation/trace/events.rst | 5 ++++ include/linux/trace_events.h | 2 +- kernel/trace/trace.h | 3 ++- kernel/trace/trace_boot.c | 2 +- kernel/trace/trace_events.c | 27 +++++++++++++------ kernel/trace/trace_events_test.c | 26 +++++++++++++++--- 7 files changed, 58 insertions(+), 16 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index e75344f4e0cd..524cad368767 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -7733,8 +7733,13 @@ Kernel parameters trace_event=:mod: The value before :mod: will only enable specific events - that are part of the module. See the above mentioned - document for more information. + that are part of the module. + + To apply a filter, use the :filter: keyword: + + trace_event=...:filter: + + See the above mentioned document for more information. trace_instance=[instance-info] [FTRACE] Create a ring buffer instance early in boot up. diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst index a1a219208ecc..88a9099f1688 100644 --- a/Documentation/trace/events.rst +++ b/Documentation/trace/events.rst @@ -118,6 +118,11 @@ In order to facilitate early boot debugging, use boot option:: event-list is a comma separated list of events. See section 2.1 for event format. +The boot option also supports the ``:filter:`` keyword to apply a filter. +The ``:filter:`` keyword needs to be at the end of the event specification:: + + ::mod::filter: + 3. Defining an event-enabled tracepoint ======================================= diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 8a396ae51fef..321f2f3a6c8e 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -883,7 +883,7 @@ extern int trace_add_event_call(struct trace_event_call *call); extern int trace_remove_event_call(struct trace_event_call *call); extern int trace_event_get_offsets(struct trace_event_call *call); -int ftrace_set_clr_event(struct trace_array *tr, const char *buf, int set); +int ftrace_set_clr_event(struct trace_array *tr, const char *buf, int set, bool handle_filter); int trace_set_clr_event(const char *system, const char *event, int set); int trace_array_set_clr_event(struct trace_array *tr, const char *system, const char *event, bool enable); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 31718ef337dc..26390e06969e 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -2511,5 +2511,6 @@ static inline int rv_init_interface(void) #endif /* _LINUX_KERNEL_TRACE_H */ #if IS_ENABLED(CONFIG_KUNIT) -void ftrace_parse_event_string(char *buf, char **match, char **sub, char **event, char **mod); +void ftrace_parse_event_string(char *buf, char **match, char **sub, char **event, char **mod, + bool handle_filter, char **filter); #endif diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 5da0a8bbb110..6ba70dac1f06 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -94,7 +94,7 @@ trace_boot_enable_events(struct trace_array *tr, struct xbc_node *node) continue; } - if (ftrace_set_clr_event(tr, buf, 1) < 0) + if (ftrace_set_clr_event(tr, buf, 1, false) < 0) pr_err("Failed to enable event: %s\n", p); } } diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index b27599c7d55d..a1ac2a02f4e2 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1458,10 +1458,21 @@ static int __ftrace_set_clr_event(struct trace_array *tr, const char *match, } VISIBLE_IF_KUNIT void -ftrace_parse_event_string(char *buf, char **match, char **sub, char **event, char **mod) +ftrace_parse_event_string(char *buf, char **match, char **sub, char **event, char **mod, + bool handle_filter, char **filter) { *event = NULL; *sub = NULL; + *filter = NULL; + + /* event filters can be appended with :filter: */ + if (handle_filter) { + *filter = strstr(buf, ":filter:"); + if (*filter) { + **filter = '\0'; + *filter += 8; + } + } /* Modules events can be appended with :mod: */ *mod = strstr(buf, ":mod:"); @@ -1501,9 +1512,9 @@ ftrace_parse_event_string(char *buf, char **match, char **sub, char **event, cha } EXPORT_SYMBOL_IF_KUNIT(ftrace_parse_event_string); -int ftrace_set_clr_event(struct trace_array *tr, const char *arg_buf, int set) +int ftrace_set_clr_event(struct trace_array *tr, const char *arg_buf, int set, bool handle_filter) { - char *event, *sub, *match, *mod; + char *event, *sub, *match, *mod, *filter; if (!tr) return -ENOENT; @@ -1512,9 +1523,9 @@ int ftrace_set_clr_event(struct trace_array *tr, const char *arg_buf, int set) if (!dupped_buf) return -ENOMEM; - ftrace_parse_event_string(dupped_buf, &match, &sub, &event, &mod); + ftrace_parse_event_string(dupped_buf, &match, &sub, &event, &mod, handle_filter, &filter); - return __ftrace_set_clr_event(tr, match, sub, event, set, mod, NULL); + return __ftrace_set_clr_event(tr, match, sub, event, set, mod, filter); } /** @@ -1596,7 +1607,7 @@ ftrace_event_write(struct file *file, const char __user *ubuf, if (*parser.buffer == '!') set = 0; - ret = ftrace_set_clr_event(tr, parser.buffer + !set, set); + ret = ftrace_set_clr_event(tr, parser.buffer + !set, set, false); if (ret) goto out_put; } @@ -4865,10 +4876,10 @@ static __init void __early_set_events(struct trace_array *tr, char *buf, bool en while ((token = strsep(&buf, ","))) { if (*token) { if (enable) { - if (ftrace_set_clr_event(tr, token, 1)) + if (ftrace_set_clr_event(tr, token, 1, true)) pr_warn("Failed to enable trace event: %s\n", token); } else { - ftrace_set_clr_event(tr, token, 0); + ftrace_set_clr_event(tr, token, 0, true); } } diff --git a/kernel/trace/trace_events_test.c b/kernel/trace/trace_events_test.c index 515d2e668c31..4a2d77fa0f58 100644 --- a/kernel/trace/trace_events_test.c +++ b/kernel/trace/trace_events_test.c @@ -8,7 +8,7 @@ struct parse_event_string_test_case { const char *input; - const char *match, *sub, *event, *mod; + const char *match, *sub, *event, *mod, *filter; }; static const struct parse_event_string_test_case parse_event_string_test_cases[] = { @@ -37,6 +37,12 @@ static const struct parse_event_string_test_case parse_event_string_test_cases[] .sub = "sub", .event = "event", }, + { + "sub:event:filter:filter", + .sub = "sub", + .event = "event", + .filter = "filter", + }, { "match", .match = "match", @@ -51,6 +57,19 @@ static const struct parse_event_string_test_case parse_event_string_test_cases[] .event = "event", .mod = "module", }, + { + "sub:event:mod:module:filter:filter", + .sub = "sub", + .event = "event", + .mod = "module", + .filter = "filter", + }, + { + "sub:event:mod:module:filter:unexpected-filter", + .sub = "sub", + .event = "event", + .mod = "module:filter:unexpected-filter", + }, }; static void @@ -72,18 +91,19 @@ KUNIT_ARRAY_PARAM(parse_event_string, parse_event_string_test_cases, parse_event static void parse_event_string(struct kunit *test) { const struct parse_event_string_test_case *params = test->param_value; - char *input, *match, *sub, *event, *mod; + char *input, *match, *sub, *event, *mod, *filter; input = kunit_kstrdup(test, params->input, GFP_KERNEL); if (!input) kunit_skip(test, "ENOMEM"); - ftrace_parse_event_string(input, &match, &sub, &event, &mod); + ftrace_parse_event_string(input, &match, &sub, &event, &mod, params->filter, &filter); EXPECT_NULL_OR_STR_EQ(test, match, params->match); EXPECT_NULL_OR_STR_EQ(test, sub, params->sub); EXPECT_NULL_OR_STR_EQ(test, event, params->event); EXPECT_NULL_OR_STR_EQ(test, mod, params->mod); + EXPECT_NULL_OR_STR_EQ(test, filter, params->filter); } static struct kunit_case trace_events_test_cases[] = { -- 2.53.0