linux-stable/fs/proc/meminfo.c
Kirill A. Shutemov dcdfdd40fa mm: Add support for unaccepted memory
UEFI Specification version 2.9 introduces the concept of memory
acceptance. Some Virtual Machine platforms, such as Intel TDX or AMD
SEV-SNP, require memory to be accepted before it can be used by the
guest. Accepting happens via a protocol specific to the Virtual Machine
platform.

There are several ways the kernel can deal with unaccepted memory:

 1. Accept all the memory during boot. It is easy to implement and it
    doesn't have runtime cost once the system is booted. The downside is
    very long boot time.

    Accept can be parallelized to multiple CPUs to keep it manageable
    (i.e. via DEFERRED_STRUCT_PAGE_INIT), but it tends to saturate
    memory bandwidth and does not scale beyond the point.

 2. Accept a block of memory on the first use. It requires more
    infrastructure and changes in page allocator to make it work, but
    it provides good boot time.

    On-demand memory accept means latency spikes every time kernel steps
    onto a new memory block. The spikes will go away once workload data
    set size gets stabilized or all memory gets accepted.

 3. Accept all memory in background. Introduce a thread (or multiple)
    that gets memory accepted proactively. It will minimize time the
    system experience latency spikes on memory allocation while keeping
    low boot time.

    This approach cannot function on its own. It is an extension of #2:
    background memory acceptance requires functional scheduler, but the
    page allocator may need to tap into unaccepted memory before that.

    The downside of the approach is that these threads also steal CPU
    cycles and memory bandwidth from the user's workload and may hurt
    user experience.

Implement #1 and #2 for now. #2 is the default. Some workloads may want
to use #1 with accept_memory=eager in kernel command line. #3 can be
implemented later based on user's demands.

Support of unaccepted memory requires a few changes in core-mm code:

  - memblock accepts memory on allocation. It serves early boot memory
    allocations and doesn't limit them to pre-accepted pool of memory.

  - page allocator accepts memory on the first allocation of the page.
    When kernel runs out of accepted memory, it accepts memory until the
    high watermark is reached. It helps to minimize fragmentation.

EFI code will provide two helpers if the platform supports unaccepted
memory:

 - accept_memory() makes a range of physical addresses accepted.

 - range_contains_unaccepted_memory() checks anything within the range
   of physical addresses requires acceptance.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>	# memblock
Link: https://lore.kernel.org/r/20230606142637.5171-2-kirill.shutemov@linux.intel.com
2023-06-06 16:38:22 +02:00

191 lines
6.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/mman.h>
#include <linux/mmzone.h>
#include <linux/memblock.h>
#include <linux/proc_fs.h>
#include <linux/percpu.h>
#include <linux/seq_file.h>
#include <linux/swap.h>
#include <linux/vmstat.h>
#include <linux/atomic.h>
#include <linux/vmalloc.h>
#ifdef CONFIG_CMA
#include <linux/cma.h>
#endif
#include <asm/page.h>
#include "internal.h"
void __attribute__((weak)) arch_report_meminfo(struct seq_file *m)
{
}
static void show_val_kb(struct seq_file *m, const char *s, unsigned long num)
{
seq_put_decimal_ull_width(m, s, num << (PAGE_SHIFT - 10), 8);
seq_write(m, " kB\n", 4);
}
static int meminfo_proc_show(struct seq_file *m, void *v)
{
struct sysinfo i;
unsigned long committed;
long cached;
long available;
unsigned long pages[NR_LRU_LISTS];
unsigned long sreclaimable, sunreclaim;
int lru;
si_meminfo(&i);
si_swapinfo(&i);
committed = vm_memory_committed();
cached = global_node_page_state(NR_FILE_PAGES) -
total_swapcache_pages() - i.bufferram;
if (cached < 0)
cached = 0;
for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
pages[lru] = global_node_page_state(NR_LRU_BASE + lru);
available = si_mem_available();
sreclaimable = global_node_page_state_pages(NR_SLAB_RECLAIMABLE_B);
sunreclaim = global_node_page_state_pages(NR_SLAB_UNRECLAIMABLE_B);
show_val_kb(m, "MemTotal: ", i.totalram);
show_val_kb(m, "MemFree: ", i.freeram);
show_val_kb(m, "MemAvailable: ", available);
show_val_kb(m, "Buffers: ", i.bufferram);
show_val_kb(m, "Cached: ", cached);
show_val_kb(m, "SwapCached: ", total_swapcache_pages());
show_val_kb(m, "Active: ", pages[LRU_ACTIVE_ANON] +
pages[LRU_ACTIVE_FILE]);
show_val_kb(m, "Inactive: ", pages[LRU_INACTIVE_ANON] +
pages[LRU_INACTIVE_FILE]);
show_val_kb(m, "Active(anon): ", pages[LRU_ACTIVE_ANON]);
show_val_kb(m, "Inactive(anon): ", pages[LRU_INACTIVE_ANON]);
show_val_kb(m, "Active(file): ", pages[LRU_ACTIVE_FILE]);
show_val_kb(m, "Inactive(file): ", pages[LRU_INACTIVE_FILE]);
show_val_kb(m, "Unevictable: ", pages[LRU_UNEVICTABLE]);
show_val_kb(m, "Mlocked: ", global_zone_page_state(NR_MLOCK));
#ifdef CONFIG_HIGHMEM
show_val_kb(m, "HighTotal: ", i.totalhigh);
show_val_kb(m, "HighFree: ", i.freehigh);
show_val_kb(m, "LowTotal: ", i.totalram - i.totalhigh);
show_val_kb(m, "LowFree: ", i.freeram - i.freehigh);
#endif
#ifndef CONFIG_MMU
show_val_kb(m, "MmapCopy: ",
(unsigned long)atomic_long_read(&mmap_pages_allocated));
#endif
show_val_kb(m, "SwapTotal: ", i.totalswap);
show_val_kb(m, "SwapFree: ", i.freeswap);
#ifdef CONFIG_ZSWAP
seq_printf(m, "Zswap: %8lu kB\n",
(unsigned long)(zswap_pool_total_size >> 10));
seq_printf(m, "Zswapped: %8lu kB\n",
(unsigned long)atomic_read(&zswap_stored_pages) <<
(PAGE_SHIFT - 10));
#endif
show_val_kb(m, "Dirty: ",
global_node_page_state(NR_FILE_DIRTY));
show_val_kb(m, "Writeback: ",
global_node_page_state(NR_WRITEBACK));
show_val_kb(m, "AnonPages: ",
global_node_page_state(NR_ANON_MAPPED));
show_val_kb(m, "Mapped: ",
global_node_page_state(NR_FILE_MAPPED));
show_val_kb(m, "Shmem: ", i.sharedram);
show_val_kb(m, "KReclaimable: ", sreclaimable +
global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE));
show_val_kb(m, "Slab: ", sreclaimable + sunreclaim);
show_val_kb(m, "SReclaimable: ", sreclaimable);
show_val_kb(m, "SUnreclaim: ", sunreclaim);
seq_printf(m, "KernelStack: %8lu kB\n",
global_node_page_state(NR_KERNEL_STACK_KB));
#ifdef CONFIG_SHADOW_CALL_STACK
seq_printf(m, "ShadowCallStack:%8lu kB\n",
global_node_page_state(NR_KERNEL_SCS_KB));
#endif
show_val_kb(m, "PageTables: ",
global_node_page_state(NR_PAGETABLE));
show_val_kb(m, "SecPageTables: ",
global_node_page_state(NR_SECONDARY_PAGETABLE));
show_val_kb(m, "NFS_Unstable: ", 0);
show_val_kb(m, "Bounce: ",
global_zone_page_state(NR_BOUNCE));
show_val_kb(m, "WritebackTmp: ",
global_node_page_state(NR_WRITEBACK_TEMP));
show_val_kb(m, "CommitLimit: ", vm_commit_limit());
show_val_kb(m, "Committed_AS: ", committed);
seq_printf(m, "VmallocTotal: %8lu kB\n",
(unsigned long)VMALLOC_TOTAL >> 10);
show_val_kb(m, "VmallocUsed: ", vmalloc_nr_pages());
show_val_kb(m, "VmallocChunk: ", 0ul);
show_val_kb(m, "Percpu: ", pcpu_nr_pages());
#ifdef CONFIG_MEMTEST
if (early_memtest_done) {
unsigned long early_memtest_bad_size_kb;
early_memtest_bad_size_kb = early_memtest_bad_size>>10;
if (early_memtest_bad_size && !early_memtest_bad_size_kb)
early_memtest_bad_size_kb = 1;
/* When 0 is reported, it means there actually was a successful test */
seq_printf(m, "EarlyMemtestBad: %5lu kB\n", early_memtest_bad_size_kb);
}
#endif
#ifdef CONFIG_MEMORY_FAILURE
seq_printf(m, "HardwareCorrupted: %5lu kB\n",
atomic_long_read(&num_poisoned_pages) << (PAGE_SHIFT - 10));
#endif
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
show_val_kb(m, "AnonHugePages: ",
global_node_page_state(NR_ANON_THPS));
show_val_kb(m, "ShmemHugePages: ",
global_node_page_state(NR_SHMEM_THPS));
show_val_kb(m, "ShmemPmdMapped: ",
global_node_page_state(NR_SHMEM_PMDMAPPED));
show_val_kb(m, "FileHugePages: ",
global_node_page_state(NR_FILE_THPS));
show_val_kb(m, "FilePmdMapped: ",
global_node_page_state(NR_FILE_PMDMAPPED));
#endif
#ifdef CONFIG_CMA
show_val_kb(m, "CmaTotal: ", totalcma_pages);
show_val_kb(m, "CmaFree: ",
global_zone_page_state(NR_FREE_CMA_PAGES));
#endif
#ifdef CONFIG_UNACCEPTED_MEMORY
show_val_kb(m, "Unaccepted: ",
global_zone_page_state(NR_UNACCEPTED));
#endif
hugetlb_report_meminfo(m);
arch_report_meminfo(m);
return 0;
}
static int __init proc_meminfo_init(void)
{
struct proc_dir_entry *pde;
pde = proc_create_single("meminfo", 0, NULL, meminfo_proc_show);
pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_meminfo_init);