From: "Rafael J. Wysocki" <[email protected]> Add acpi_os_map_memory_fast_path() and set ACPI_USE_FAST_PATH_MAPPING to allow acpi_ex_system_memory_space_handler() to avoid unnecessary memory mapping and unmapping overhead by retaining all memory mappings created by it until the memory opregions associated with them go away.
Signed-off-by: Rafael J. Wysocki <[email protected]> --- drivers/acpi/osl.c | 65 +++++++++++++++++++++++-------- include/acpi/platform/aclinux.h | 4 ++ include/acpi/platform/aclinuxex.h | 3 ++ 3 files changed, 56 insertions(+), 16 deletions(-) diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 749ae3e32193..b8537ce89ea2 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -306,21 +306,8 @@ static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr) iounmap(vaddr); } -/** - * acpi_os_map_iomem - Get a virtual address for a given physical address range. - * @phys: Start of the physical address range to map. - * @size: Size of the physical address range to map. - * - * Look up the given physical address range in the list of existing ACPI memory - * mappings. If found, get a reference to it and return a pointer to it (its - * virtual address). If not found, map it, add it to that list and return a - * pointer to it. - * - * During early init (when acpi_permanent_mmap has not been set yet) this - * routine simply calls __acpi_map_table() to get the job done. - */ -void __iomem __ref -*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) +static void __iomem __ref *__acpi_os_map_iomem(acpi_physical_address phys, + acpi_size size, bool fast_path) { struct acpi_ioremap *map; void __iomem *virt; @@ -332,8 +319,12 @@ void __iomem __ref return NULL; } - if (!acpi_permanent_mmap) + if (!acpi_permanent_mmap) { + if (WARN_ON(fast_path)) + return NULL; + return __acpi_map_table((unsigned long)phys, size); + } mutex_lock(&acpi_ioremap_lock); /* Check if there's a suitable mapping already. */ @@ -343,6 +334,11 @@ void __iomem __ref goto out; } + if (fast_path) { + mutex_unlock(&acpi_ioremap_lock); + return NULL; + } + map = kzalloc(sizeof(*map), GFP_KERNEL); if (!map) { mutex_unlock(&acpi_ioremap_lock); @@ -370,6 +366,25 @@ void __iomem __ref mutex_unlock(&acpi_ioremap_lock); return map->virt + (phys - map->phys); } + +/** + * acpi_os_map_iomem - Get a virtual address for a given physical address range. + * @phys: Start of the physical address range to map. + * @size: Size of the physical address range to map. + * + * Look up the given physical address range in the list of existing ACPI memory + * mappings. If found, get a reference to it and return a pointer representing + * its virtual address. If not found, map it, add it to that list and return a + * pointer representing its virtual address. + * + * During early init (when acpi_permanent_mmap has not been set yet) call + * __acpi_map_table() to obtain the mapping. + */ +void __iomem __ref *acpi_os_map_iomem(acpi_physical_address phys, + acpi_size size) +{ + return __acpi_os_map_iomem(phys, size, false); +} EXPORT_SYMBOL_GPL(acpi_os_map_iomem); void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size) @@ -378,6 +393,24 @@ void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size) } EXPORT_SYMBOL_GPL(acpi_os_map_memory); +/** + * acpi_os_map_memory_fast_path - Fast-path physical-to-virtual address mapping. + * @phys: Start of the physical address range to map. + * @size: Size of the physical address range to map. + * + * Look up the given physical address range in the list of existing ACPI memory + * mappings. If found, get a reference to it and return a pointer representing + * its virtual address. If not found, return NULL. + * + * During early init (when acpi_permanent_mmap has not been set yet) log a + * warning and return NULL. + */ +void __ref *acpi_os_map_memory_fast_path(acpi_physical_address phys, + acpi_size size) +{ + return __acpi_os_map_iomem(phys, size, true); +} + /* Must be called with mutex_lock(&acpi_ioremap_lock) */ static bool acpi_os_drop_map_ref(struct acpi_ioremap *map, bool defer) { diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h index 784e294dc74c..1a5f8037e3d5 100644 --- a/include/acpi/platform/aclinux.h +++ b/include/acpi/platform/aclinux.h @@ -118,6 +118,10 @@ #define USE_NATIVE_ALLOCATE_ZEROED +/* Use fast-path memory mapping to optimize memory opregions handling */ + +#define ACPI_USE_FAST_PATH_MAPPING + /* * Overrides for in-kernel ACPICA */ diff --git a/include/acpi/platform/aclinuxex.h b/include/acpi/platform/aclinuxex.h index ad6b905358c5..c64b836ba455 100644 --- a/include/acpi/platform/aclinuxex.h +++ b/include/acpi/platform/aclinuxex.h @@ -141,6 +141,9 @@ static inline void acpi_os_terminate_debugger(void) * OSL interfaces added by Linux */ +void *acpi_os_map_memory_fast_path(acpi_physical_address where, + acpi_size length); + #endif /* __KERNEL__ */ #endif /* __ACLINUXEX_H__ */ -- 2.26.2
