| Message ID | 20241031040952.109057-16-mario.limonciello@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On Thu, Oct 31, 2024, at 12:09 AM, Mario Limonciello wrote: > If multiple platform profile handlers have been registered, don't allow > switching to profiles unique to only one handler. > > Tested-by: Matthew Schwartz <matthew.schwartz@linux.dev> > Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> > --- > drivers/acpi/platform_profile.c | 38 +++++++++++++++++++++++++-------- > 1 file changed, 29 insertions(+), 9 deletions(-) > > diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c > index 7bd32f1e8d834..90cbc0de4d5bc 100644 > --- a/drivers/acpi/platform_profile.c > +++ b/drivers/acpi/platform_profile.c > @@ -29,23 +29,43 @@ static bool platform_profile_is_registered(void) > return !list_empty(&platform_profile_handler_list); > } > > +static unsigned long platform_profile_get_choices(void) > +{ > + struct platform_profile_handler *handler; > + unsigned long aggregate = 0; > + int i; > + > + lockdep_assert_held(&profile_lock); > + list_for_each_entry(handler, &platform_profile_handler_list, list) { > + unsigned long individual = 0; > + > + for_each_set_bit(i, handler->choices, PLATFORM_PROFILE_LAST) > + individual |= BIT(i); > + if (!aggregate) > + aggregate = individual; > + else > + aggregate &= individual; > + } > + > + return aggregate; > +} > + I realise this is very unlikely but isn't it possible that the number of profiles could overflow unsigned long number of bits? As handler->choices is an array of them. It should loop through BITS_TO_LONGS(PLATFORM_PROFILE_LAST) cycles. Also wondered if this could be simplified with setting aggregate = ~0 and then & it with each handler->choices to avoid having to scan individual bits? > static ssize_t platform_profile_choices_show(struct device *dev, > struct device_attribute *attr, > char *buf) > { > + unsigned long choices; > int len = 0; > int i; > > - scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) { > - if (!cur_profile) > - return -ENODEV; > + scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) > + choices = platform_profile_get_choices(); > > - for_each_set_bit(i, cur_profile->choices, PLATFORM_PROFILE_LAST) { > - if (len == 0) > - len += sysfs_emit_at(buf, len, "%s", profile_names[i]); > - else > - len += sysfs_emit_at(buf, len, " %s", profile_names[i]); > - } > + for_each_set_bit(i, &choices, PLATFORM_PROFILE_LAST) { > + if (len == 0) > + len += sysfs_emit_at(buf, len, "%s", profile_names[i]); > + else > + len += sysfs_emit_at(buf, len, " %s", profile_names[i]); > } > len += sysfs_emit_at(buf, len, "\n"); > > -- > 2.43.0 This links in to the later patches - but I was wondering if at profile registration/unregistration if building a local choices selection would simplify things. Then instead of needing platform_profile_get_choices, you can just use your local choices selection to make decisions on what to show, or cycle to - instead of having to cycle thru the profiles and bits every time. Not 100% sure how well it would work out - but might be simpler and faster? Mark
diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c index 7bd32f1e8d834..90cbc0de4d5bc 100644 --- a/drivers/acpi/platform_profile.c +++ b/drivers/acpi/platform_profile.c @@ -29,23 +29,43 @@ static bool platform_profile_is_registered(void) return !list_empty(&platform_profile_handler_list); } +static unsigned long platform_profile_get_choices(void) +{ + struct platform_profile_handler *handler; + unsigned long aggregate = 0; + int i; + + lockdep_assert_held(&profile_lock); + list_for_each_entry(handler, &platform_profile_handler_list, list) { + unsigned long individual = 0; + + for_each_set_bit(i, handler->choices, PLATFORM_PROFILE_LAST) + individual |= BIT(i); + if (!aggregate) + aggregate = individual; + else + aggregate &= individual; + } + + return aggregate; +} + static ssize_t platform_profile_choices_show(struct device *dev, struct device_attribute *attr, char *buf) { + unsigned long choices; int len = 0; int i; - scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) { - if (!cur_profile) - return -ENODEV; + scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) + choices = platform_profile_get_choices(); - for_each_set_bit(i, cur_profile->choices, PLATFORM_PROFILE_LAST) { - if (len == 0) - len += sysfs_emit_at(buf, len, "%s", profile_names[i]); - else - len += sysfs_emit_at(buf, len, " %s", profile_names[i]); - } + for_each_set_bit(i, &choices, PLATFORM_PROFILE_LAST) { + if (len == 0) + len += sysfs_emit_at(buf, len, "%s", profile_names[i]); + else + len += sysfs_emit_at(buf, len, " %s", profile_names[i]); } len += sysfs_emit_at(buf, len, "\n");