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

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Sat, Apr 07, 2012 at 08:10:23AM +0800, Lin Ming wrote:
> On Sat, Apr 7, 2012 at 6:23 AM, Konrad Rzeszutek Wilk
> <konrad.wilk@oracle.com> 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@oracle.com>
> > 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?

That is possible too.
> Do you mean to save a function call by converting it to a value?

That was my thinking.
> 
> Looks good to me.
> 
> Thanks,
> Lin Ming
> 
> >
> >    Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> >
> > 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);
> >  }
> >
> >  /*
> > --