Commit cbe2f5a6 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

tracing: allow tracing of suspend/resume & hibernation code again 



Impact: widen function-tracing to suspend+resume (and hibernation) sequences

Now that the ftrace kernel thread is gone, we can allow tracing
during suspend/resume again.

So revert these two commits:

  f42ac38c "ftrace: disable tracing for suspend to ram"
  41108eb1 "ftrace: disable tracing for hibernation"

This should be tested very carefully, as it could interact with
altneratives instruction patching, etc.

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent a0a70c73

kernel/power/disk.c

+3 −10
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 
#include <linux/console.h>

#include <linux/cpu.h>

#include <linux/freezer.h>

#include <linux/ftrace.h>



#include "power.h"
@@ -257,7 +256,7 @@ static int create_image(int platform_mode) 


int hibernation_snapshot(int platform_mode)

{

	int error, ftrace_save;

	int error;



	/* Free memory before shutting down devices. */

	error = swsusp_shrink_memory();
@@ -269,7 +268,6 @@ int hibernation_snapshot(int platform_mode) 
		goto Close;



	suspend_console();

	ftrace_save = __ftrace_enabled_save();

	error = device_suspend(PMSG_FREEZE);

	if (error)

		goto Recover_platform;
@@ -299,7 +297,6 @@ int hibernation_snapshot(int platform_mode) 
 Resume_devices:

	device_resume(in_suspend ?

		(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);

	__ftrace_enabled_restore(ftrace_save);

	resume_console();

 Close:

	platform_end(platform_mode);
@@ -370,11 +367,10 @@ static int resume_target_kernel(void) 


int hibernation_restore(int platform_mode)

{

	int error, ftrace_save;

	int error;



	pm_prepare_console();

	suspend_console();

	ftrace_save = __ftrace_enabled_save();

	error = device_suspend(PMSG_QUIESCE);

	if (error)

		goto Finish;
@@ -389,7 +385,6 @@ int hibernation_restore(int platform_mode) 
	platform_restore_cleanup(platform_mode);

	device_resume(PMSG_RECOVER);

 Finish:

	__ftrace_enabled_restore(ftrace_save);

	resume_console();

	pm_restore_console();

	return error;
@@ -402,7 +397,7 @@ int hibernation_restore(int platform_mode) 


int hibernation_platform_enter(void)

{

	int error, ftrace_save;

	int error;



	if (!hibernation_ops)

		return -ENOSYS;
@@ -417,7 +412,6 @@ int hibernation_platform_enter(void) 
		goto Close;



	suspend_console();

	ftrace_save = __ftrace_enabled_save();

	error = device_suspend(PMSG_HIBERNATE);

	if (error) {

		if (hibernation_ops->recover)
@@ -452,7 +446,6 @@ int hibernation_platform_enter(void) 
	hibernation_ops->finish();

 Resume_devices:

	device_resume(PMSG_RESTORE);

	__ftrace_enabled_restore(ftrace_save);

	resume_console();

 Close:

	hibernation_ops->end();

kernel/power/main.c

+1 −4
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 
#include <linux/freezer.h>

#include <linux/vmstat.h>

#include <linux/syscalls.h>

#include <linux/ftrace.h>



#include "power.h"
@@ -317,7 +316,7 @@ static int suspend_enter(suspend_state_t state) 
 */

int suspend_devices_and_enter(suspend_state_t state)

{

	int error, ftrace_save;

	int error;



	if (!suspend_ops)

		return -ENOSYS;
@@ -328,7 +327,6 @@ int suspend_devices_and_enter(suspend_state_t state) 
			goto Close;

	}

	suspend_console();

	ftrace_save = __ftrace_enabled_save();

	suspend_test_start();

	error = device_suspend(PMSG_SUSPEND);

	if (error) {
@@ -360,7 +358,6 @@ int suspend_devices_and_enter(suspend_state_t state) 
	suspend_test_start();

	device_resume(PMSG_RESUME);

	suspend_test_finish("resume devices");

	__ftrace_enabled_restore(ftrace_save);

	resume_console();

 Close:

	if (suspend_ops->end)

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