[for-next][PATCH 00/12] tracing: More updates for 5.15

[for-next][PATCH 00/12] tracing: More updates for 5.15

[Steven Rostedt]

More tracing updates for 5.15:

 - Add migrate-disable counter to tracing header

 - Fix error handling in event probes

 - Fix missed unlock in osnoise in error path

 - Fix merge issue with tools/bootconfig

 - Clean up bootconfig data when init memory is removed

 - Have kernel command lines override bootconfig options

 - Increase field counts for synthetic events

 - Have histograms dynamic allocate event elements to save space

 - Fixes in testing and documentation


Artem Bityutskiy (1):
      tracing: synth events: increase max fields count

Dan Carpenter (1):
      tracing: Fix some alloc_event_probe() error handling bugs

Julio Faracco (1):
      bootconfig: Fix missing return check of xbc_node_compose_key function

Masami Hiramatsu (5):
      init: bootconfig: Remove all bootconfig data when the init memory is removed
      init/bootconfig: Reorder init parameter from bootconfig and cmdline
      docs: bootconfig: Add how to use bootconfig for kernel parameters
      tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh
      tools/bootconfig: Show whole test command for each test case

Qiang.Zhang (1):
      tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads()

Steven Rostedt (VMware) (1):
      selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events

Thomas Gleixner (1):
      tracing: Add migrate-disabled counter to tracing output.

Tom Zanussi (1):
      tracing: Dynamically allocate the per-elt hist_elt_data array

----
 Documentation/admin-guide/bootconfig.rst           | 39 +++++++++++++++++++++-
 init/main.c                                        | 37 ++++++++++++++------
 kernel/trace/trace.c                               | 26 +++++++++++----
 kernel/trace/trace_eprobe.c                        |  5 +--
 kernel/trace/trace_events.c                        |  1 +
 kernel/trace/trace_events_hist.c                   | 14 ++++++--
 kernel/trace/trace_osnoise.c                       |  6 ++--
 kernel/trace/trace_output.c                        | 11 ++++--
 kernel/trace/trace_synth.h                         |  2 +-
 tools/bootconfig/main.c                            |  4 ++-
 tools/bootconfig/scripts/ftrace2bconf.sh           |  4 +--
 tools/bootconfig/test-bootconfig.sh                |  4 +--
 .../ftrace/test.d/dynevent/add_remove_eprobe.tc    |  2 +-
 13 files changed, 119 insertions(+), 36 deletions(-)

[for-next][PATCH 01/12] tracing: Add migrate-disabled counter to tracing output.

[Steven Rostedt]

From: Thomas Gleixner <tglx@linutronix.de>

migrate_disable() forbids task migration to another CPU. It is available
since v5.11 and has already users such as highmem or BPF. It is useful
to observe this task state in tracing which already has other states
like the preemption counter.

Instead of adding the migrate disable counter as a new entry to struct
trace_entry, which would extend the whole struct by four bytes, it is
squashed into the preempt-disable counter. The lower four bits represent
the preemption counter, the upper four bits represent the migrate
disable counter. Both counter shouldn't exceed 15 but if they do, there
is a safety net which caps the value at 15.

Add the migrate-disable counter to the trace entry so it shows up in the
trace. Due to the users mentioned above, it is already possible to
observe it:

|  bash-1108    [000] ...21    73.950578: rss_stat: mm_id=2213312838 curr=0 type=MM_ANONPAGES size=8192B
|  bash-1108    [000] d..31    73.951222: irq_disable: caller=flush_tlb_mm_range+0x115/0x130 parent=ptep_clear_flush+0x42/0x50
|  bash-1108    [000] d..31    73.951222: tlb_flush: pages:1 reason:local mm shootdown (3)

The last value is the migrate-disable counter.

Things that popped up:
- trace_print_lat_context() does not print the migrate counter. Not sure
  if it should. It is used in "verbose" mode and uses 8 digits and I'm
  not sure ther is something processing the value.

- trace_define_common_fields() now defines a different variable. This
  probably breaks things. No ide what to do in order to preserve the old
  behaviour. Since this is used as a filter it should be split somehow
  to be able to match both nibbles here.

Link: https://lkml.kernel.org/r/20210810132625.ylssabmsrkygokuv@linutronix.de

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: patch description.]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ SDR: Removed change to common_preempt_count field name ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace.c        | 26 +++++++++++++++++++-------
 kernel/trace/trace_events.c |  1 +
 kernel/trace/trace_output.c | 11 ++++++++---
 3 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 489924cde4f8..b554e18924f8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2603,6 +2603,15 @@ enum print_line_t trace_handle_return(struct trace_seq *s)
 }
 EXPORT_SYMBOL_GPL(trace_handle_return);
 
+static unsigned short migration_disable_value(void)
+{
+#if defined(CONFIG_SMP)
+	return current->migration_disabled;
+#else
+	return 0;
+#endif
+}
+
 unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
 {
 	unsigned int trace_flags = irqs_status;
@@ -2621,7 +2630,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
 		trace_flags |= TRACE_FLAG_NEED_RESCHED;
 	if (test_preempt_need_resched())
 		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
-	return (trace_flags << 16) | (pc & 0xff);
+	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
+		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
 }
 
 struct ring_buffer_event *
@@ -4189,9 +4199,10 @@ static void print_lat_help_header(struct seq_file *m)
 		    "#                  | / _----=> need-resched    \n"
 		    "#                  || / _---=> hardirq/softirq \n"
 		    "#                  ||| / _--=> preempt-depth   \n"
-		    "#                  |||| /     delay            \n"
-		    "#  cmd     pid     ||||| time  |   caller      \n"
-		    "#     \\   /        |||||  \\    |   /         \n");
+		    "#                  |||| / _-=> migrate-disable \n"
+		    "#                  ||||| /     delay           \n"
+		    "#  cmd     pid     |||||| time  |   caller     \n"
+		    "#     \\   /        ||||||  \\    |    /       \n");
 }
 
 static void print_event_info(struct array_buffer *buf, struct seq_file *m)
@@ -4229,9 +4240,10 @@ static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file
 	seq_printf(m, "#                            %.*s / _----=> need-resched\n", prec, space);
 	seq_printf(m, "#                            %.*s| / _---=> hardirq/softirq\n", prec, space);
 	seq_printf(m, "#                            %.*s|| / _--=> preempt-depth\n", prec, space);
-	seq_printf(m, "#                            %.*s||| /     delay\n", prec, space);
-	seq_printf(m, "#           TASK-PID  %.*s CPU#  ||||   TIMESTAMP  FUNCTION\n", prec, "     TGID   ");
-	seq_printf(m, "#              | |    %.*s   |   ||||      |         |\n", prec, "       |    ");
+	seq_printf(m, "#                            %.*s||| / _-=> migrate-disable\n", prec, space);
+	seq_printf(m, "#                            %.*s|||| /     delay\n", prec, space);
+	seq_printf(m, "#           TASK-PID  %.*s CPU#  |||||  TIMESTAMP  FUNCTION\n", prec, "     TGID   ");
+	seq_printf(m, "#              | |    %.*s   |   |||||     |         |\n", prec, "       |    ");
 }
 
 void
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 1349b6de5eeb..830b3b9940f4 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -181,6 +181,7 @@ static int trace_define_common_fields(void)
 
 	__common_field(unsigned short, type);
 	__common_field(unsigned char, flags);
+	/* Holds both preempt_count and migrate_disable */
 	__common_field(unsigned char, preempt_count);
 	__common_field(int, pid);
 
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index a0bf446bb034..c2ca40e8595b 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -492,8 +492,13 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 	trace_seq_printf(s, "%c%c%c",
 			 irqs_off, need_resched, hardsoft_irq);
 
-	if (entry->preempt_count)
-		trace_seq_printf(s, "%x", entry->preempt_count);
+	if (entry->preempt_count & 0xf)
+		trace_seq_printf(s, "%x", entry->preempt_count & 0xf);
+	else
+		trace_seq_putc(s, '.');
+
+	if (entry->preempt_count & 0xf0)
+		trace_seq_printf(s, "%x", entry->preempt_count >> 4);
 	else
 		trace_seq_putc(s, '.');
 
@@ -656,7 +661,7 @@ int trace_print_lat_context(struct trace_iterator *iter)
 		trace_seq_printf(
 			s, "%16s %7d %3d %d %08x %08lx ",
 			comm, entry->pid, iter->cpu, entry->flags,
-			entry->preempt_count, iter->idx);
+			entry->preempt_count & 0xf, iter->idx);
 	} else {
 		lat_print_generic(s, entry, iter->cpu);
 	}
-- 
2.32.0

[for-next][PATCH 02/12] tracing: Fix some alloc_event_probe() error handling bugs

[Steven Rostedt]

From: Dan Carpenter <dan.carpenter@oracle.com>

There are two bugs in this code.  First, if the kzalloc() fails it leads
to a NULL dereference of "ep" on the next line.  Second, if the
alloc_event_probe() function returns an error then it leads to an
error pointer dereference in the caller.

Link: https://lkml.kernel.org/r/20210824115150.GI31143@kili

Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_eprobe.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index 56a96e9750cf..3044b762cbd7 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -151,7 +151,7 @@ static struct trace_eprobe *alloc_event_probe(const char *group,
 
 	ep = kzalloc(struct_size(ep, tp.args, nargs), GFP_KERNEL);
 	if (!ep) {
-		trace_event_put_ref(ep->event);
+		trace_event_put_ref(event);
 		goto error;
 	}
 	ep->event = event;
@@ -851,7 +851,8 @@ static int __trace_eprobe_create(int argc, const char *argv[])
 		ret = PTR_ERR(ep);
 		/* This must return -ENOMEM, else there is a bug */
 		WARN_ON_ONCE(ret != -ENOMEM);
-		goto error;	/* We know ep is not allocated */
+		ep = NULL;
+		goto error;
 	}
 
 	argc -= 2; argv += 2;
-- 
2.32.0

[for-next][PATCH 03/12] tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads()

[Steven Rostedt]

From: "Qiang.Zhang" <qiang.zhang@windriver.com>

When start_kthread() return error, the cpus_read_unlock() need
to be called.

Link: https://lkml.kernel.org/r/20210831022919.27630-1-qiang.zhang@windriver.com

Cc: <stable@vger.kernel.org>
Fixes: c8895e271f79 ("trace/osnoise: Support hotplug operations")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Qiang.Zhang <qiang.zhang@windriver.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_osnoise.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index 65b08b8e5bf8..ce053619f289 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -1548,7 +1548,7 @@ static int start_kthread(unsigned int cpu)
 static int start_per_cpu_kthreads(struct trace_array *tr)
 {
 	struct cpumask *current_mask = &save_cpumask;
-	int retval;
+	int retval = 0;
 	int cpu;
 
 	cpus_read_lock();
@@ -1568,13 +1568,13 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
 		retval = start_kthread(cpu);
 		if (retval) {
 			stop_per_cpu_kthreads();
-			return retval;
+			break;
 		}
 	}
 
 	cpus_read_unlock();
 
-	return 0;
+	return retval;
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
-- 
2.32.0

[for-next][PATCH 04/12] init: bootconfig: Remove all bootconfig data when the init memory is removed

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@kernel.org>

Since the bootconfig is used only in the init functions,
it doesn't need to keep the data after boot. Free it when
the init memory is removed.

Link: https://lkml.kernel.org/r/163077084958.222577.5924961258513004428.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 init/main.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/init/main.c b/init/main.c
index 8d97aba78c3a..d35c4a865adb 100644
--- a/init/main.c
+++ b/init/main.c
@@ -468,7 +468,12 @@ static void __init setup_boot_config(void)
 	return;
 }
 
-#else
+static void __init exit_boot_config(void)
+{
+	xbc_destroy_all();
+}
+
+#else	/* !CONFIG_BOOT_CONFIG */
 
 static void __init setup_boot_config(void)
 {
@@ -481,7 +486,11 @@ static int __init warn_bootconfig(char *str)
 	pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n");
 	return 0;
 }
-#endif
+
+#define exit_boot_config()	do {} while (0)
+
+#endif	/* CONFIG_BOOT_CONFIG */
+
 early_param("bootconfig", warn_bootconfig);
 
 /* Change NUL term back to "=", to make "param" the whole string. */
@@ -1493,6 +1502,7 @@ static int __ref kernel_init(void *unused)
 	kprobe_free_init_mem();
 	ftrace_free_init_mem();
 	kgdb_free_init_mem();
+	exit_boot_config();
 	free_initmem();
 	mark_readonly();
 
-- 
2.32.0

[for-next][PATCH 05/12] init/bootconfig: Reorder init parameter from bootconfig and cmdline

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@kernel.org>

Reorder the init parameters from bootconfig and kernel cmdline
so that the kernel cmdline always be the last part of the
parameters as below.

 " -- "[bootconfig init params][cmdline init params]

This change will help us to prevent that bootconfig init params
overwrite the init params which user gives in the command line.

Link: https://lkml.kernel.org/r/163077085675.222577.5665176468023636160.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 init/main.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/init/main.c b/init/main.c
index d35c4a865adb..d08caed17c7f 100644
--- a/init/main.c
+++ b/init/main.c
@@ -153,10 +153,10 @@ static char *extra_init_args;
 #ifdef CONFIG_BOOT_CONFIG
 /* Is bootconfig on command line? */
 static bool bootconfig_found;
-static bool initargs_found;
+static size_t initargs_offs;
 #else
 # define bootconfig_found false
-# define initargs_found false
+# define initargs_offs 0
 #endif
 
 static char *execute_command;
@@ -422,9 +422,9 @@ static void __init setup_boot_config(void)
 	if (IS_ERR(err) || !bootconfig_found)
 		return;
 
-	/* parse_args() stops at '--' and returns an address */
+	/* parse_args() stops at the next param of '--' and returns an address */
 	if (err)
-		initargs_found = true;
+		initargs_offs = err - tmp_cmdline;
 
 	if (!data) {
 		pr_err("'bootconfig' found on command line, but no bootconfig found\n");
@@ -655,16 +655,21 @@ static void __init setup_command_line(char *command_line)
 		 * Append supplemental init boot args to saved_command_line
 		 * so that user can check what command line options passed
 		 * to init.
+		 * The order should always be
+		 * " -- "[bootconfig init-param][cmdline init-param]
 		 */
-		len = strlen(saved_command_line);
-		if (initargs_found) {
-			saved_command_line[len++] = ' ';
+		if (initargs_offs) {
+			len = xlen + initargs_offs;
+			strcpy(saved_command_line + len, extra_init_args);
+			len += ilen - 4;	/* strlen(extra_init_args) */
+			strcpy(saved_command_line + len,
+				boot_command_line + initargs_offs - 1);
 		} else {
+			len = strlen(saved_command_line);
 			strcpy(saved_command_line + len, " -- ");
 			len += 4;
+			strcpy(saved_command_line + len, extra_init_args);
 		}
-
-		strcpy(saved_command_line + len, extra_init_args);
 	}
 }
 
-- 
2.32.0

[for-next][PATCH 06/12] docs: bootconfig: Add how to use bootconfig for kernel parameters

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@kernel.org>

Add a section to describe how to use the bootconfig for
specifying kernel and init parameters. This is an important
section because it is the reason why this document is under
the admin-guide.

Link: https://lkml.kernel.org/r/163077086399.222577.5881779375643977991.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 Documentation/admin-guide/bootconfig.rst | 39 +++++++++++++++++++++++-
 1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst
index 6a79f2e59396..a1860fc0ca88 100644
--- a/Documentation/admin-guide/bootconfig.rst
+++ b/Documentation/admin-guide/bootconfig.rst
@@ -178,7 +178,7 @@ update the boot loader and the kernel image itself as long as the boot
 loader passes the correct initrd file size. If by any chance, the boot
 loader passes a longer size, the kernel fails to find the bootconfig data.
 
-To do this operation, Linux kernel provides "bootconfig" command under
+To do this operation, Linux kernel provides ``bootconfig`` command under
 tools/bootconfig, which allows admin to apply or delete the config file
 to/from initrd image. You can build it by the following command::
 
@@ -196,6 +196,43 @@ To remove the config from the image, you can use -d option as below::
 Then add "bootconfig" on the normal kernel command line to tell the
 kernel to look for the bootconfig at the end of the initrd file.
 
+
+Kernel parameters via Boot Config
+=================================
+
+In addition to the kernel command line, the boot config can be used for
+passing the kernel parameters. All the key-value pairs under ``kernel``
+key will be passed to kernel cmdline directly. Moreover, the key-value
+pairs under ``init`` will be passed to init process via the cmdline.
+The parameters are concatinated with user-given kernel cmdline string
+as the following order, so that the command line parameter can override
+bootconfig parameters (this depends on how the subsystem handles parameters
+but in general, earlier parameter will be overwritten by later one.)::
+
+ [bootconfig params][cmdline params] -- [bootconfig init params][cmdline init params]
+
+Here is an example of the bootconfig file for kernel/init parameters.::
+
+ kernel {
+   root = 01234567-89ab-cdef-0123-456789abcd
+ }
+ init {
+  splash
+ }
+
+This will be copied into the kernel cmdline string as the following::
+
+ root="01234567-89ab-cdef-0123-456789abcd" -- splash
+
+If user gives some other command line like,::
+
+ ro bootconfig -- quiet
+
+The final kernel cmdline will be the following::
+
+ root="01234567-89ab-cdef-0123-456789abcd" ro bootconfig -- splash quiet
+
+
 Config File Limitation
 ======================
 
-- 
2.32.0

[for-next][PATCH 07/12] tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@kernel.org>

Since tracing_on indicates only "1" (default) or "0", ftrace2bconf.sh
only need to check the value is "0".

Link: https://lkml.kernel.org/r/163077087144.222577.6888011847727968737.stgit@devnote2

Fixes: 55ed4560774d ("tools/bootconfig: Add tracing_on support to helper scripts")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 tools/bootconfig/scripts/ftrace2bconf.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/bootconfig/scripts/ftrace2bconf.sh b/tools/bootconfig/scripts/ftrace2bconf.sh
index fbaf07dc91bf..6183b36c6846 100755
--- a/tools/bootconfig/scripts/ftrace2bconf.sh
+++ b/tools/bootconfig/scripts/ftrace2bconf.sh
@@ -239,8 +239,8 @@ instance_options() { # [instance-name]
 		emit_kv $PREFIX.cpumask = $val
 	fi
 	val=`cat $INSTANCE/tracing_on`
-	if [ `echo $val | sed -e s/f//g`x != x ]; then
-		emit_kv $PREFIX.tracing_on = $val
+	if [ "$val" = "0" ]; then
+		emit_kv $PREFIX.tracing_on = 0
 	fi
 
 	val=`cat $INSTANCE/current_tracer`
-- 
2.32.0

[for-next][PATCH 08/12] bootconfig: Fix missing return check of xbc_node_compose_key function

[Steven Rostedt]

From: Julio Faracco <jcfaracco@gmail.com>

The function `xbc_show_list should` handle the keys during the
composition. Even the errors returned by the compose function. Instead
of removing the `ret` variable, it should save the value and show the
exact error. This missing variable is causing a compilation issue also.

Link: https://lkml.kernel.org/r/163077087861.222577.12884543474750968146.stgit@devnote2

Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key")
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vgar.kernel.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 tools/bootconfig/main.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c
index f45fa992e01d..fd67496a947f 100644
--- a/tools/bootconfig/main.c
+++ b/tools/bootconfig/main.c
@@ -111,9 +111,11 @@ static void xbc_show_list(void)
 	char key[XBC_KEYLEN_MAX];
 	struct xbc_node *leaf;
 	const char *val;
+	int ret;
 
 	xbc_for_each_key_value(leaf, val) {
-		if (xbc_node_compose_key(leaf, key, XBC_KEYLEN_MAX) < 0) {
+		ret = xbc_node_compose_key(leaf, key, XBC_KEYLEN_MAX);
+		if (ret < 0) {
 			fprintf(stderr, "Failed to compose key %d\n", ret);
 			break;
 		}
-- 
2.32.0

[for-next][PATCH 09/12] tools/bootconfig: Show whole test command for each test case

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@kernel.org>

Show whole test command instead of only the 3rd argument.
This will clear to show what will be actually tested by
each test case.

Link: https://lkml.kernel.org/r/163077088607.222577.14786016266462495017.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 tools/bootconfig/test-bootconfig.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/bootconfig/test-bootconfig.sh b/tools/bootconfig/test-bootconfig.sh
index baed891d0ba4..f68e2e9eef8b 100755
--- a/tools/bootconfig/test-bootconfig.sh
+++ b/tools/bootconfig/test-bootconfig.sh
@@ -26,7 +26,7 @@ trap cleanup EXIT TERM
 NO=1
 
 xpass() { # pass test command
-  echo "test case $NO ($3)... "
+  echo "test case $NO ($*)... "
   if ! ($@ && echo "\t\t[OK]"); then
      echo "\t\t[NG]"; NG=$((NG + 1))
   fi
@@ -34,7 +34,7 @@ xpass() { # pass test command
 }
 
 xfail() { # fail test command
-  echo "test case $NO ($3)... "
+  echo "test case $NO ($*)... "
   if ! (! $@ && echo "\t\t[OK]"); then
      echo "\t\t[NG]"; NG=$((NG + 1))
   fi
-- 
2.32.0

[for-next][PATCH 10/12] tracing: synth events: increase max fields count

[Steven Rostedt]

From: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Sometimes it is useful to construct larger synthetic trace events. Increase
'SYNTH_FIELDS_MAX' (maximum number of fields in a synthetic event) from 32 to
64.

Link: https://lkml.kernel.org/r/20210901135513.3087062-1-dedekind1@gmail.com

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_synth.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace_synth.h b/kernel/trace/trace_synth.h
index 4007fe95cf42..b29595fe3ac5 100644
--- a/kernel/trace/trace_synth.h
+++ b/kernel/trace/trace_synth.h
@@ -5,7 +5,7 @@
 #include "trace_dynevent.h"
 
 #define SYNTH_SYSTEM		"synthetic"
-#define SYNTH_FIELDS_MAX	32
+#define SYNTH_FIELDS_MAX	64
 
 #define STR_VAR_LEN_MAX		MAX_FILTER_STR_VAL /* must be multiple of sizeof(u64) */
 
-- 
2.32.0

[for-next][PATCH 11/12] tracing: Dynamically allocate the per-elt hist_elt_data array

[Steven Rostedt]

From: Tom Zanussi <zanussi@kernel.org>

Setting the hist_elt_data.field_var_str[] array unconditionally to a
size of SYNTH_FIELD_MAX elements wastes space unnecessarily.  The
actual number of elements needed can be calculated at run-time
instead.

In most cases, this will save a lot of space since it's a per-elt
array which isn't normally close to being full.  It also allows us to
increase SYNTH_FIELD_MAX without worrying about even more wastage when
we do that.

Link: https://lkml.kernel.org/r/d52ae0ad5e1b59af7c4f54faf3fc098461fd82b3.camel@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_events_hist.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 9d91b1c06957..a6061a69aa84 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -508,7 +508,8 @@ struct track_data {
 struct hist_elt_data {
 	char *comm;
 	u64 *var_ref_vals;
-	char *field_var_str[SYNTH_FIELDS_MAX];
+	char **field_var_str;
+	int n_field_var_str;
 };
 
 struct snapshot_context {
@@ -1401,9 +1402,11 @@ static void hist_elt_data_free(struct hist_elt_data *elt_data)
 {
 	unsigned int i;
 
-	for (i = 0; i < SYNTH_FIELDS_MAX; i++)
+	for (i = 0; i < elt_data->n_field_var_str; i++)
 		kfree(elt_data->field_var_str[i]);
 
+	kfree(elt_data->field_var_str);
+
 	kfree(elt_data->comm);
 	kfree(elt_data);
 }
@@ -1451,6 +1454,13 @@ static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
 
 	size = STR_VAR_LEN_MAX;
 
+	elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL);
+	if (!elt_data->field_var_str) {
+		hist_elt_data_free(elt_data);
+		return -EINVAL;
+	}
+	elt_data->n_field_var_str = n_str;
+
 	for (i = 0; i < n_str; i++) {
 		elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
 		if (!elt_data->field_var_str[i]) {
-- 
2.32.0

[for-next][PATCH 12/12] selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events

[Steven Rostedt]

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

The original test for adding and removing eprobes used synthetic events
and retrieved the filename from the open system call at the end of the
system call. This would allow it to always be loaded into the page tables
when accessed.

Masami suggested that the test was too complex for just testing add and
remove, so it was changed to test just adding and removing an event probe
on top of the start of the open system call event. Now it is possible that
the filename will not be loaded into memory at the time the eprobe is
triggered, and will result in "(fault)" being displayed in the event. This
causes the test to fail.

Account for "(fault)" also being one of the values of the filename field
of the event probe.

Link: https://lkml.kernel.org/r/20210907230429.5783d519@rorschach.local.home

Fixes: 079db70794ec5 ("selftests/ftrace: Add test case to test adding and removing of event probe")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 .../selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
index 25a3da4eaa44..5f5b2ba3e557 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
@@ -22,7 +22,7 @@ ls
 echo 0 > events/eprobes/$EPROBE/enable
 
 content=`grep '^ *ls-' trace | grep 'file='`
-nocontent=`grep '^ *ls-' trace | grep 'file=' | grep -v -e '"/' -e '"."'` || true
+nocontent=`grep '^ *ls-' trace | grep 'file=' | grep -v -e '"/' -e '"."' -e '(fault)' ` || true
 
 if [ -z "$content" ]; then
 	exit_fail
-- 
2.32.0

Re: [for-next][PATCH 08/12] bootconfig: Fix missing return check of xbc_node_compose_key function

[Steven Rostedt]

On Wed, 08 Sep 2021 15:18:59 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> From: Julio Faracco <jcfaracco@gmail.com>
> 
> The function `xbc_show_list should` handle the keys during the
> composition. Even the errors returned by the compose function. Instead
> of removing the `ret` variable, it should save the value and show the
> exact error. This missing variable is causing a compilation issue also.
> 
> Link: https://lkml.kernel.org/r/163077087861.222577.12884543474750968146.stgit@devnote2
> 
> Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key")
> Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
> Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

> Cc: stable@vgar.kernel.org

Oops, a typo. That should be: stable@vger.kernel.org or
stable@kernel.org. There is no "vgar" ;-)

I'll fix this up.

-- Steve


> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>