diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-power | 17 | ||||
| -rw-r--r-- | Documentation/power/interface.txt | 13 | ||||
| -rw-r--r-- | include/linux/pm.h | 4 | ||||
| -rw-r--r-- | kernel/power/disk.c | 37 |
4 files changed, 60 insertions, 11 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index d882f8093871..dcff4d0623ad 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -21,7 +21,7 @@ Description: these states. What: /sys/power/disk -Date: August 2006 +Date: September 2006 Contact: Rafael J. Wysocki <rjw@sisk.pl> Description: The /sys/power/disk file controls the operating mode of the @@ -39,6 +39,19 @@ Description: 'reboot' - the memory image will be saved by the kernel and the system will be rebooted. + Additionally, /sys/power/disk can be used to turn on one of the + two testing modes of the suspend-to-disk mechanism: 'testproc' + or 'test'. If the suspend-to-disk mechanism is in the + 'testproc' mode, writing 'disk' to /sys/power/state will cause + the kernel to disable nonboot CPUs and freeze tasks, wait for 5 + seconds, unfreeze tasks and enable nonboot CPUs. If it is in + the 'test' mode, writing 'disk' to /sys/power/state will cause + the kernel to disable nonboot CPUs and freeze tasks, shrink + memory, suspend devices, wait for 5 seconds, resume devices, + unfreeze tasks and enable nonboot CPUs. Then, we are able to + look in the log messages and work out, for example, which code + is being slow and which device drivers are misbehaving. + The suspend-to-disk method may be chosen by writing to this file one of the accepted strings: @@ -46,6 +59,8 @@ Description: 'platform' 'shutdown' 'reboot' + 'testproc' + 'test' It will only change to 'firmware' or 'platform' if the system supports that. diff --git a/Documentation/power/interface.txt b/Documentation/power/interface.txt index a66bec222b16..74311d7e0f3c 100644 --- a/Documentation/power/interface.txt +++ b/Documentation/power/interface.txt @@ -30,6 +30,17 @@ testing). The system will support either 'firmware' or 'platform', and that is known a priori. But, the user may choose 'shutdown' or 'reboot' as alternatives. +Additionally, /sys/power/disk can be used to turn on one of the two testing +modes of the suspend-to-disk mechanism: 'testproc' or 'test'. If the +suspend-to-disk mechanism is in the 'testproc' mode, writing 'disk' to +/sys/power/state will cause the kernel to disable nonboot CPUs and freeze +tasks, wait for 5 seconds, unfreeze tasks and enable nonboot CPUs. If it is +in the 'test' mode, writing 'disk' to /sys/power/state will cause the kernel +to disable nonboot CPUs and freeze tasks, shrink memory, suspend devices, wait +for 5 seconds, resume devices, unfreeze tasks and enable nonboot CPUs. Then, +we are able to look in the log messages and work out, for example, which code +is being slow and which device drivers are misbehaving. + Reading from this file will display what the mode is currently set to. Writing to this file will accept one of @@ -37,6 +48,8 @@ to. Writing to this file will accept one of 'platform' 'shutdown' 'reboot' + 'testproc' + 'test' It will only change to 'firmware' or 'platform' if the system supports it. diff --git a/include/linux/pm.h b/include/linux/pm.h index 6b27e07aef19..070394e846d0 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -116,7 +116,9 @@ typedef int __bitwise suspend_disk_method_t; #define PM_DISK_PLATFORM ((__force suspend_disk_method_t) 2) #define PM_DISK_SHUTDOWN ((__force suspend_disk_method_t) 3) #define PM_DISK_REBOOT ((__force suspend_disk_method_t) 4) -#define PM_DISK_MAX ((__force suspend_disk_method_t) 5) +#define PM_DISK_TEST ((__force suspend_disk_method_t) 5) +#define PM_DISK_TESTPROC ((__force suspend_disk_method_t) 6) +#define PM_DISK_MAX ((__force suspend_disk_method_t) 7) struct pm_ops { suspend_disk_method_t pm_disk_mode; diff --git a/kernel/power/disk.c b/kernel/power/disk.c index d3a158a60312..b1fb7866b0b3 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -71,7 +71,7 @@ static inline void platform_finish(void) static int prepare_processes(void) { - int error; + int error = 0; pm_prepare_console(); @@ -84,6 +84,12 @@ static int prepare_processes(void) goto thaw; } + if (pm_disk_mode == PM_DISK_TESTPROC) { + printk("swsusp debug: Waiting for 5 seconds.\n"); + mdelay(5000); + goto thaw; + } + /* Free memory before shutting down devices. */ if (!(error = swsusp_shrink_memory())) return 0; @@ -120,13 +126,21 @@ int pm_suspend_disk(void) if (error) return error; + if (pm_disk_mode == PM_DISK_TESTPROC) + goto Thaw; + suspend_console(); error = device_suspend(PMSG_FREEZE); if (error) { resume_console(); printk("Some devices failed to suspend\n"); - unprepare_processes(); - return error; + goto Thaw; + } + + if (pm_disk_mode == PM_DISK_TEST) { + printk("swsusp debug: Waiting for 5 seconds.\n"); + mdelay(5000); + goto Done; } pr_debug("PM: snapshotting memory.\n"); @@ -143,16 +157,17 @@ int pm_suspend_disk(void) power_down(pm_disk_mode); else { swsusp_free(); - unprepare_processes(); - return error; + goto Thaw; } - } else + } else { pr_debug("PM: Image restored successfully.\n"); + } swsusp_free(); Done: device_resume(); resume_console(); + Thaw: unprepare_processes(); return error; } @@ -249,6 +264,8 @@ static const char * const pm_disk_modes[] = { [PM_DISK_PLATFORM] = "platform", [PM_DISK_SHUTDOWN] = "shutdown", [PM_DISK_REBOOT] = "reboot", + [PM_DISK_TEST] = "test", + [PM_DISK_TESTPROC] = "testproc", }; /** @@ -303,17 +320,19 @@ static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n) } } if (mode) { - if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT) + if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT || + mode == PM_DISK_TEST || mode == PM_DISK_TESTPROC) { pm_disk_mode = mode; - else { + } else { if (pm_ops && pm_ops->enter && (mode == pm_ops->pm_disk_mode)) pm_disk_mode = mode; else error = -EINVAL; } - } else + } else { error = -EINVAL; + } pr_debug("PM: suspend-to-disk mode set to '%s'\n", pm_disk_modes[mode]); |