Commit 43175623 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'trace-v5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace 

Pull more tracing updates from Steven Rostedt:

 - 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

 - Fix bootconfig to loop only on subkeys

 - 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

* tag 'trace-v5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/boot: Fix to loop on only subkeys
  selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events
  tracing: Dynamically allocate the per-elt hist_elt_data array
  tracing: synth events: increase max fields count
  tools/bootconfig: Show whole test command for each test case
  bootconfig: Fix missing return check of xbc_node_compose_key function
  tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh
  docs: bootconfig: Add how to use bootconfig for kernel parameters
  init/bootconfig: Reorder init parameter from bootconfig and cmdline
  init: bootconfig: Remove all bootconfig data when the init memory is removed
  tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads()
  tracing: Fix some alloc_event_probe() error handling bugs
  tracing: Add migrate-disabled counter to tracing output.
parents f154c806 cfd79983

Documentation/admin-guide/bootconfig.rst

+38 −1
Original line number Diff line number Diff line
@@ -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

======================

init/main.c

+26 −11
Original line number Diff line number Diff line
@@ -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");
@@ -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. */
@@ -646,18 +655,23 @@ 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);

		}

	}

}



/*

 * We need to finalize in a non-__init function or else race conditions
@@ -1494,6 +1508,7 @@ 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();

kernel/trace/trace.c

+19 −7
Original line number Diff line number Diff line
@@ -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

kernel/trace/trace_boot.c

+3 −3
Original line number Diff line number Diff line
@@ -522,14 +522,14 @@ trace_boot_init_events(struct trace_array *tr, struct xbc_node *node) 
	if (!node)

		return;

	/* per-event key starts with "event.GROUP.EVENT" */

	xbc_node_for_each_child(node, gnode) {

	xbc_node_for_each_subkey(node, gnode) {

		data = xbc_node_get_data(gnode);

		if (!strcmp(data, "enable")) {

			enable_all = true;

			continue;

		}

		enable = false;

		xbc_node_for_each_child(gnode, enode) {

		xbc_node_for_each_subkey(gnode, enode) {

			data = xbc_node_get_data(enode);

			if (!strcmp(data, "enable")) {

				enable = true;
@@ -625,7 +625,7 @@ trace_boot_init_instances(struct xbc_node *node) 
	if (!node)

		return;



	xbc_node_for_each_child(node, inode) {

	xbc_node_for_each_subkey(node, inode) {

		p = xbc_node_get_data(inode);

		if (!p || *p == '\0')

			continue;

kernel/trace/trace_eprobe.c

+3 −2
Original line number Diff line number Diff line
@@ -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;