Re: ACPI: Move module parameter gts and bfs to sleep.c

From: Lin Ming
Date: Fri Apr 06 2012 - 20:10:21 EST


On Sat, Apr 7, 2012 at 6:23 AM, Konrad Rzeszutek Wilk
<konrad.wilk@xxxxxxxxxx> wrote:
> Hey Lin,
>
> I was wondering if you are OK with exporting the wake_sleep_flags
> function so that other callers of acpi_enter_sleep (which are
> outside the sleep.c) could use it?
>
> Specifically this patch
> http://git.kernel.org/?p=linux/kernel/git/konrad/xen.git;a=blobdiff;f=include/xen/acpi.h;h=ebaabbbe91877cc9d7188254463b4a591f6bb81d;hp=48a9c0171b658904b33a82df0d4aa31fe8b8ed81;hb=331a7ed09457ca7b6c31170c5d59a09e6f1e02c2;hpb=68504cdd16c26735078f65a0bdc8eeb9f0c493ea
>
> [which I was hoping to post for v3.5]
> .. which in 3.3 would call acpi_enter_sleep_state without
> trouble but with 3.4 it needs a parameter.
>
> This little patch (compile tested, but not actually run):
>
> commit 8f9f29819fa71de17e2e6f38fc50c4156dc3dada
> Author: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
> Date:   Fri Apr 6 17:53:51 2012 -0400
>
>    ACPI: Convert wake_sleep_flags to a value instead of function.
>
>    With commit a2ef5c4fd44ce3922435139393b89f2cce47f576
>    "ACPI: Move module parameter gts and bfs to sleep.c" the wake_sleep_flags
>    is required when calling acpi_enter_sleep_state, which means
>    that if there are functions outside the sleep.c code they
>    can't get get the wake_sleep_flags values.
>
>    This converts the function in to a exported value and converts
>    the module config operands to a function.

Why not just export the function?
Do you mean to save a function call by converting it to a value?

Looks good to me.

Thanks,
Lin Ming

>
>    Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
>
> diff --git a/arch/x86/kernel/acpi/sleep.h b/arch/x86/kernel/acpi/sleep.h
> index 4d3feb5..f84e9cd 100644
> --- a/arch/x86/kernel/acpi/sleep.h
> +++ b/arch/x86/kernel/acpi/sleep.h
> @@ -9,6 +9,8 @@ extern long saved_magic;
>
>  extern int wakeup_pmode_return;
>
> +extern unsigned wake_sleep_flags;
> +
>  extern unsigned long acpi_copy_wakeup_routine(unsigned long);
>  extern void wakeup_long64(void);
>
> diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
> index 6a8d4d3..dcee73a 100644
> --- a/drivers/acpi/sleep.c
> +++ b/drivers/acpi/sleep.c
> @@ -28,23 +28,23 @@
>  #include "internal.h"
>  #include "sleep.h"
>
> +u8 wake_sleep_flags = ACPI_NO_OPTIONAL_METHODS;
>  static unsigned int gts, bfs;
> -module_param(gts, uint, 0644);
> -module_param(bfs, uint, 0644);
> -MODULE_PARM_DESC(gts, "Enable evaluation of _GTS on suspend.");
> -MODULE_PARM_DESC(bfs, "Enable evaluation of _BFS on resume".);
> -
> -static u8 wake_sleep_flags(void)
> +static int set_param_wake_flag(const char *val, struct kernel_param *kp)
>  {
> -       u8 flags = ACPI_NO_OPTIONAL_METHODS;
> +       int ret = param_set_int(val, kp);
>
>        if (gts)
> -               flags |= ACPI_EXECUTE_GTS;
> +               wake_sleep_flags |= ACPI_EXECUTE_GTS;
>        if (bfs)
> -               flags |= ACPI_EXECUTE_BFS;
> +               wake_sleep_flags |= ACPI_EXECUTE_BFS;
>
> -       return flags;
> +       return ret;
>  }
> +module_param_call(gts, set_param_wake_flag, param_get_int, &gts, 0644);
> +module_param_call(bfs, set_param_wake_flag, param_get_int, &bfs, 0644);
> +MODULE_PARM_DESC(gts, "Enable evaluation of _GTS on suspend.");
> +MODULE_PARM_DESC(bfs, "Enable evaluation of _BFS on resume".);
>
>  static u8 sleep_states[ACPI_S_STATE_COUNT];
>
> @@ -263,7 +263,6 @@ static int acpi_suspend_enter(suspend_state_t pm_state)
>  {
>        acpi_status status = AE_OK;
>        u32 acpi_state = acpi_target_sleep_state;
> -       u8 flags = wake_sleep_flags();
>        int error;
>
>        ACPI_FLUSH_CPU_CACHE();
> @@ -271,7 +270,7 @@ static int acpi_suspend_enter(suspend_state_t pm_state)
>        switch (acpi_state) {
>        case ACPI_STATE_S1:
>                barrier();
> -               status = acpi_enter_sleep_state(acpi_state, flags);
> +               status = acpi_enter_sleep_state(acpi_state, wake_sleep_flags);
>                break;
>
>        case ACPI_STATE_S3:
> @@ -288,7 +287,7 @@ static int acpi_suspend_enter(suspend_state_t pm_state)
>        acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
>
>        /* Reprogram control registers and execute _BFS */
> -       acpi_leave_sleep_state_prep(acpi_state, flags);
> +       acpi_leave_sleep_state_prep(acpi_state, wake_sleep_flags);
>
>        /* ACPI 3.0 specs (P62) says that it's the responsibility
>         * of the OSPM to clear the status bit [ implying that the
> @@ -552,30 +551,27 @@ static int acpi_hibernation_begin(void)
>
>  static int acpi_hibernation_enter(void)
>  {
> -       u8 flags = wake_sleep_flags();
>        acpi_status status = AE_OK;
>
>        ACPI_FLUSH_CPU_CACHE();
>
>        /* This shouldn't return.  If it returns, we have a problem */
> -       status = acpi_enter_sleep_state(ACPI_STATE_S4, flags);
> +       status = acpi_enter_sleep_state(ACPI_STATE_S4, wake_sleep_flags);
>        /* Reprogram control registers and execute _BFS */
> -       acpi_leave_sleep_state_prep(ACPI_STATE_S4, flags);
> +       acpi_leave_sleep_state_prep(ACPI_STATE_S4, wake_sleep_flags);
>
>        return ACPI_SUCCESS(status) ? 0 : -EFAULT;
>  }
>
>  static void acpi_hibernation_leave(void)
>  {
> -       u8 flags = wake_sleep_flags();
> -
>        /*
>         * If ACPI is not enabled by the BIOS and the boot kernel, we need to
>         * enable it here.
>         */
>        acpi_enable();
>        /* Reprogram control registers and execute _BFS */
> -       acpi_leave_sleep_state_prep(ACPI_STATE_S4, flags);
> +       acpi_leave_sleep_state_prep(ACPI_STATE_S4, wake_sleep_flags);
>        /* Check the hardware signature */
>        if (facs && s4_hardware_signature != facs->hardware_signature) {
>                printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
> @@ -830,12 +826,10 @@ static void acpi_power_off_prepare(void)
>
>  static void acpi_power_off(void)
>  {
> -       u8 flags = wake_sleep_flags();
> -
>        /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
>        printk(KERN_DEBUG "%s called\n", __func__);
>        local_irq_disable();
> -       acpi_enter_sleep_state(ACPI_STATE_S5, flags);
> +       acpi_enter_sleep_state(ACPI_STATE_S5, wake_sleep_flags);
>  }
>
>  /*
> --
--
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