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27 March 2024, 02:37:15 UTC
Revision bb668da6d6f2bec8a63838c098d9515eccb22cc4 authored by Suresh Siddha on 18 January 2010, 20:10:49 UTC, committed by Linus Torvalds on 18 January 2010, 22:15:28 UTC 
x86, apic: use logical flat for systems with <= 8 logical cpus
 
We can use logical flat mode if there are <= 8 logical cpu's
(irrespective of physical apic id values).  This will enable simplified
and efficient IPI and device interrupt routing on such platforms.

This has been tested to work on both Intel and AMD platforms.
Exceptions like IBM summit platform which can't use logical flat mode
are addressed by using OEM platform checks.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Chris McDermott <lcm@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent dfea91d
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Tip revision: bb668da6d6f2bec8a63838c098d9515eccb22cc4 authored by Suresh Siddha on 18 January 2010, 20:10:49 UTC
x86, apic: use logical flat for systems with <= 8 logical cpus
Tip revision: bb668da
show_mem.c 
/*
 * Generic show_mem() implementation
 *
 * Copyright (C) 2008 Johannes Weiner <hannes@saeurebad.de>
 * All code subject to the GPL version 2.
 */

#include <linux/mm.h>
#include <linux/nmi.h>
#include <linux/quicklist.h>

void show_mem(void)
{
	pg_data_t *pgdat;
	unsigned long total = 0, reserved = 0, shared = 0,
		nonshared = 0, highmem = 0;

	printk(KERN_INFO "Mem-Info:\n");
	show_free_areas();

	for_each_online_pgdat(pgdat) {
		unsigned long i, flags;

		pgdat_resize_lock(pgdat, &flags);
		for (i = 0; i < pgdat->node_spanned_pages; i++) {
			struct page *page;
			unsigned long pfn = pgdat->node_start_pfn + i;

			if (unlikely(!(i % MAX_ORDER_NR_PAGES)))
				touch_nmi_watchdog();

			if (!pfn_valid(pfn))
				continue;

			page = pfn_to_page(pfn);

			if (PageHighMem(page))
				highmem++;

			if (PageReserved(page))
				reserved++;
			else if (page_count(page) == 1)
				nonshared++;
			else if (page_count(page) > 1)
				shared += page_count(page) - 1;

			total++;
		}
		pgdat_resize_unlock(pgdat, &flags);
	}

	printk(KERN_INFO "%lu pages RAM\n", total);
#ifdef CONFIG_HIGHMEM
	printk(KERN_INFO "%lu pages HighMem\n", highmem);
#endif
	printk(KERN_INFO "%lu pages reserved\n", reserved);
	printk(KERN_INFO "%lu pages shared\n", shared);
	printk(KERN_INFO "%lu pages non-shared\n", nonshared);
#ifdef CONFIG_QUICKLIST
	printk(KERN_INFO "%lu pages in pagetable cache\n",
		quicklist_total_size());
#endif
}
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