[igt-dev] [PATCH i-g-t v3 1/2] lib/igt_aux: Disable console suspend for suspend test

[Kamil Konieczny]

Hi Anshuman,

On 2023-06-22 at 11:32:27 +0530, Anshuman Gupta wrote:
> We need no_console_suspend to be enable in order to dump the suspend
> logs over serial console before attempting the suspend during
> CI Execution.
> Therefore disable the console_suspend using printk module parameters
> while executing suspend test.
> 
> v2:
> - Keep console_suspend restore only in exit handler. [Ashutosh]
> - Don't skip the test on open error, while opening printk parameters,
>   instead print warning. [Kmail]
> 
> v3:
> - Fixed cosmetics and return value comment. [Ashutosh]

Please add also documentation at functions using it about new
functionality.

Regards,
Kamil

> 
> Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> Reviewed-by: Badal Nilawar <badal.nilawar at intel.com>
> Reviewed-by: Ashutosh Dixit <ashutosh.dixit at intel.com>
> ---
>  lib/igt_aux.c | 37 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
> 
> diff --git a/lib/igt_aux.c b/lib/igt_aux.c
> index 386e257834..25bf720b8e 100644
> --- a/lib/igt_aux.c
> +++ b/lib/igt_aux.c
> @@ -702,6 +702,10 @@ void igt_print_activity(void)
>  }
>  
>  static int autoresume_delay;
> +bool __console_suspend_saved_state;
> +
> +#define SYSFS_MODULE_PRINTK "/sys/module/printk/parameters/"
> +#define CONSOLE_SUSPEND_DISABLE false
>  
>  static const char *suspend_state_name[] = {
>  	[SUSPEND_STATE_FREEZE] = "freeze",
> @@ -907,6 +911,38 @@ static bool is_mem_sleep_state_supported(int power_dir, enum igt_mem_sleep state
>  	return str;
>  }
>  
> +static void igt_aux_pm_suspend_dbg_restore_exit_handler(int sig)
> +{
> +	int sysfs_fd;
> +
> +	sysfs_fd = open(SYSFS_MODULE_PRINTK, O_RDONLY);
> +
> +	if (sysfs_fd < 0)
> +		return;
> +
> +	igt_sysfs_set_boolean(sysfs_fd, "console_suspend", __console_suspend_saved_state);
> +	close(sysfs_fd);
> +}
> +
> +static void igt_aux_enable_pm_suspend_dbg(void)
> +{
> +	int sysfs_fd;
> +
> +	sysfs_fd = open(SYSFS_MODULE_PRINTK, O_RDONLY);
> +	if (sysfs_fd > 0) {
> +		__console_suspend_saved_state = igt_sysfs_get_boolean(sysfs_fd, "console_suspend");
> +
> +		if (!igt_sysfs_set_boolean(sysfs_fd, "console_suspend", CONSOLE_SUSPEND_DISABLE))
> +			igt_warn("Unable to disable console suspend\n");
> +
> +		igt_install_exit_handler(igt_aux_pm_suspend_dbg_restore_exit_handler);
> +	} else {
> +		igt_warn("Unable to open printk parameters Err:%d\n", errno);
> +	}
> +
> +	close(sysfs_fd);
> +}
> +
>  /**
>   * igt_system_suspend_autoresume:
>   * @state: an #igt_suspend_state, the target suspend state
> @@ -945,6 +981,7 @@ void igt_system_suspend_autoresume(enum igt_suspend_state state,
>  		      "Suspend to disk requires swap space.\n");
>  
>  	orig_test = get_suspend_test(power_dir);
> +	igt_aux_enable_pm_suspend_dbg();
>  
>  	if (state == SUSPEND_STATE_S3) {
>  		orig_mem_sleep = get_mem_sleep();
> -- 
> 2.25.1
>