Commit b24c2a92 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
Browse files

x86: Move find_smp_config() earlier and avoid bootmem usage 



Move the find_smp_config() call to before bootmem is initialized.
Use reserve_early() instead of reserve_bootmem() in it.

This simplifies the code, we only need to call find_smp_config()
once and can remove the now unneeded reserve parameter from
x86_init_mpparse::find_smp_config.

We thus also reduce x86's dependency on bootmem allocations.

Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B0BB9F2.70907@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent eb41c8be

arch/x86/include/asm/mpspec.h

+3 −8
Original line number Diff line number Diff line
@@ -71,12 +71,7 @@ static inline void early_get_smp_config(void) 


static inline void find_smp_config(void)

{

	x86_init.mpparse.find_smp_config(1);

}



static inline void early_find_smp_config(void)

{

	x86_init.mpparse.find_smp_config(0);

	x86_init.mpparse.find_smp_config();

}



#ifdef CONFIG_X86_MPPARSE
@@ -89,7 +84,7 @@ extern void default_mpc_oem_bus_info(struct mpc_bus *m, char *str); 
# else

#  define default_mpc_oem_bus_info NULL

# endif

extern void default_find_smp_config(unsigned int reserve);

extern void default_find_smp_config(void);

extern void default_get_smp_config(unsigned int early);

#else

static inline void early_reserve_e820_mpc_new(void) { }
@@ -97,7 +92,7 @@ static inline void early_reserve_e820_mpc_new(void) { } 
#define default_mpc_apic_id NULL

#define default_smp_read_mpc_oem NULL

#define default_mpc_oem_bus_info NULL

#define default_find_smp_config x86_init_uint_noop

#define default_find_smp_config x86_init_noop

#define default_get_smp_config x86_init_uint_noop

#endif

arch/x86/include/asm/x86_init.h

+1 −1
Original line number Diff line number Diff line
@@ -26,7 +26,7 @@ struct x86_init_mpparse { 
	void (*smp_read_mpc_oem)(struct mpc_table *mpc);

	void (*mpc_oem_pci_bus)(struct mpc_bus *m);

	void (*mpc_oem_bus_info)(struct mpc_bus *m, char *name);

	void (*find_smp_config)(unsigned int reserve);

	void (*find_smp_config)(void);

	void (*get_smp_config)(unsigned int early);

};

arch/x86/kernel/apic/numaq_32.c

+0 −5
Original line number Diff line number Diff line
@@ -263,11 +263,6 @@ static void __init smp_read_mpc_oem(struct mpc_table *mpc) 


static __init void early_check_numaq(void)

{

	/*

	 * Find possible boot-time SMP configuration:

	 */

	early_find_smp_config();



	/*

	 * get boot-time SMP configuration:

	 */

arch/x86/kernel/mpparse.c

+12 −32
Original line number Diff line number Diff line
@@ -667,36 +667,18 @@ void __init default_get_smp_config(unsigned int early) 
	 */

}



static void __init smp_reserve_bootmem(struct mpf_intel *mpf)

static void __init smp_reserve_memory(struct mpf_intel *mpf)

{

	unsigned long size = get_mpc_size(mpf->physptr);

#ifdef CONFIG_X86_32

	/*

	 * We cannot access to MPC table to compute table size yet,

	 * as only few megabytes from the bottom is mapped now.

	 * PC-9800's MPC table places on the very last of physical

	 * memory; so that simply reserving PAGE_SIZE from mpf->physptr

	 * yields BUG() in reserve_bootmem.

	 * also need to make sure physptr is below than max_low_pfn

	 * we don't need reserve the area above max_low_pfn

	 */

	unsigned long end = max_low_pfn * PAGE_SIZE;



	if (mpf->physptr < end) {

		if (mpf->physptr + size > end)

			size = end - mpf->physptr;

		reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT);

	}

#else

	reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT);

#endif

	reserve_early(mpf->physptr, mpf->physptr+size, "MP-table mpc");

}



static int __init smp_scan_config(unsigned long base, unsigned long length,

				  unsigned reserve)

static int __init smp_scan_config(unsigned long base, unsigned long length)

{

	unsigned int *bp = phys_to_virt(base);

	struct mpf_intel *mpf;

	unsigned long mem;



	apic_printk(APIC_VERBOSE, "Scan SMP from %p for %ld bytes.\n",

			bp, length);
@@ -717,12 +699,10 @@ static int __init smp_scan_config(unsigned long base, unsigned long length, 
			printk(KERN_INFO "found SMP MP-table at [%p] %llx\n",

			       mpf, (u64)virt_to_phys(mpf));



			if (!reserve)

				return 1;

			reserve_bootmem_generic(virt_to_phys(mpf), sizeof(*mpf),

						BOOTMEM_DEFAULT);

			mem = virt_to_phys(mpf);

			reserve_early(mem, mem + sizeof(*mpf), "MP-table mpf");

			if (mpf->physptr)

				smp_reserve_bootmem(mpf);

				smp_reserve_memory(mpf);



			return 1;

		}
@@ -732,7 +712,7 @@ static int __init smp_scan_config(unsigned long base, unsigned long length, 
	return 0;

}



void __init default_find_smp_config(unsigned int reserve)

void __init default_find_smp_config(void)

{

	unsigned int address;
@@ -744,9 +724,9 @@ void __init default_find_smp_config(unsigned int reserve) 
	 * 2) Scan the top 1K of base RAM

	 * 3) Scan the 64K of bios

	 */

	if (smp_scan_config(0x0, 0x400, reserve) ||

	    smp_scan_config(639 * 0x400, 0x400, reserve) ||

	    smp_scan_config(0xF0000, 0x10000, reserve))

	if (smp_scan_config(0x0, 0x400) ||

	    smp_scan_config(639 * 0x400, 0x400) ||

	    smp_scan_config(0xF0000, 0x10000))

		return;

	/*

	 * If it is an SMP machine we should know now, unless the
@@ -767,7 +747,7 @@ void __init default_find_smp_config(unsigned int reserve) 


	address = get_bios_ebda();

	if (address)

		smp_scan_config(address, 0x400, reserve);

		smp_scan_config(address, 0x400);

}



#ifdef CONFIG_X86_IO_APIC

arch/x86/kernel/setup.c

+5 −5
Original line number Diff line number Diff line
@@ -913,6 +913,11 @@ void __init setup_arch(char **cmdline_p) 


	early_acpi_boot_init();



	/*

	 * Find and reserve possible boot-time SMP configuration:

	 */

	find_smp_config();



#ifdef CONFIG_ACPI_NUMA

	/*

	 * Parse SRAT to discover nodes.
@@ -927,11 +932,6 @@ void __init setup_arch(char **cmdline_p) 


	initmem_init(0, max_pfn, acpi, k8);



	/*

	 * Find and reserve possible boot-time SMP configuration:

	 */

	find_smp_config();



#ifdef CONFIG_X86_64

	/*

	 * dma32_reserve_bootmem() allocates bootmem which may conflict

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