Commit 2d6d9fd3 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Linus Torvalds
Browse files

ACPI: Introduce acpi_os_ioremap() 



Commit ca9b600b ("ACPI / PM: Make suspend_nvs_save() use
acpi_os_map_memory()") attempted to prevent the code in osl.c and nvs.c
from using different ioremap() variants by making the latter use
acpi_os_map_memory() for mapping the NVS pages.  However, that also
requires acpi_os_unmap_memory() to be used for unmapping them, which
causes synchronize_rcu() to be executed many times in a row
unnecessarily and introduces substantial delays during resume on some
systems.

Instead of using acpi_os_map_memory() for mapping the NVS pages in nvs.c
introduce acpi_os_ioremap() calling ioremap_cache() and make the code in
both osl.c and nvs.c use it.

Reported-by: default avatarJeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8d99641f

drivers/acpi/nvs.c

+4 −3
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/mm.h>

#include <linux/slab.h>

#include <linux/acpi.h>

#include <linux/acpi_io.h>

#include <acpi/acpiosxf.h>



/*
@@ -80,7 +81,7 @@ void suspend_nvs_free(void) 
			free_page((unsigned long)entry->data);

			entry->data = NULL;

			if (entry->kaddr) {

				acpi_os_unmap_memory(entry->kaddr, entry->size);

				iounmap(entry->kaddr);

				entry->kaddr = NULL;

			}

		}
@@ -114,7 +115,7 @@ int suspend_nvs_save(void) 


	list_for_each_entry(entry, &nvs_list, node)

		if (entry->data) {

			entry->kaddr = acpi_os_map_memory(entry->phys_start,

			entry->kaddr = acpi_os_ioremap(entry->phys_start,

						    entry->size);

			if (!entry->kaddr) {

				suspend_nvs_free();

drivers/acpi/osl.c

+7 −5
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ 
#include <linux/workqueue.h>

#include <linux/nmi.h>

#include <linux/acpi.h>

#include <linux/acpi_io.h>

#include <linux/efi.h>

#include <linux/ioport.h>

#include <linux/list.h>
@@ -302,9 +303,10 @@ void __iomem *__init_refok 
acpi_os_map_memory(acpi_physical_address phys, acpi_size size)

{

	struct acpi_ioremap *map, *tmp_map;

	unsigned long flags, pg_sz;

	unsigned long flags;

	void __iomem *virt;

	phys_addr_t pg_off;

	acpi_physical_address pg_off;

	acpi_size pg_sz;



	if (phys > ULONG_MAX) {

		printk(KERN_ERR PREFIX "Cannot map memory that high\n");
@@ -320,7 +322,7 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) 


	pg_off = round_down(phys, PAGE_SIZE);

	pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off;

	virt = ioremap_cache(pg_off, pg_sz);

	virt = acpi_os_ioremap(pg_off, pg_sz);

	if (!virt) {

		kfree(map);

		return NULL;
@@ -642,7 +644,7 @@ acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width) 
	virt_addr = acpi_map_vaddr_lookup(phys_addr, size);

	rcu_read_unlock();

	if (!virt_addr) {

		virt_addr = ioremap_cache(phys_addr, size);

		virt_addr = acpi_os_ioremap(phys_addr, size);

		unmap = 1;

	}

	if (!value)
@@ -678,7 +680,7 @@ acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width) 
	virt_addr = acpi_map_vaddr_lookup(phys_addr, size);

	rcu_read_unlock();

	if (!virt_addr) {

		virt_addr = ioremap_cache(phys_addr, size);

		virt_addr = acpi_os_ioremap(phys_addr, size);

		unmap = 1;

	}

include/linux/acpi.h

+0 −3
Original line number Diff line number Diff line
@@ -306,9 +306,6 @@ extern acpi_status acpi_pci_osc_control_set(acpi_handle handle, 
					     u32 *mask, u32 req);

extern void acpi_early_init(void);



int acpi_os_map_generic_address(struct acpi_generic_address *addr);

void acpi_os_unmap_generic_address(struct acpi_generic_address *addr);



#else	/* !CONFIG_ACPI */



#define acpi_disabled 1

include/linux/acpi_io.h

0 → 100644
+16 −0
Original line number Diff line number Diff line 
#ifndef _ACPI_IO_H_

#define _ACPI_IO_H_



#include <linux/io.h>

#include <acpi/acpi.h>



static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,

					    acpi_size size)

{

       return ioremap_cache(phys, size);

}



int acpi_os_map_generic_address(struct acpi_generic_address *addr);

void acpi_os_unmap_generic_address(struct acpi_generic_address *addr);



#endif

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