mm/page_reporting: export reporting order as module parameter

The macro PAGE_REPORTING_MIN_ORDER is defined as the page reporting
threshold.  It can't be adjusted at runtime.

This introduces a variable (@page_reporting_order) to replace the marcro
(PAGE_REPORTING_MIN_ORDER).  MAX_ORDER is assigned to it initially,
meaning the page reporting is disabled.  It will be specified by driver if
valid one is provided.  Otherwise, it will fall back to @pageblock_order.
It's also exported so that the page reporting order can be adjusted at
runtime.

Link: https://lkml.kernel.org/r/20210625014710.42954-3-gshan@redhat.com
Signed-off-by: Gavin Shan <gshan@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Gavin Shan 2021-06-28 19:35:19 -07:00 committed by Linus Torvalds
parent 5631de543a
commit f58780a8e3
3 changed files with 15 additions and 5 deletions

View File

@ -3566,6 +3566,12 @@
off: turn off poisoning (default)
on: turn on poisoning
page_reporting.page_reporting_order=
[KNL] Minimal page reporting order
Format: <integer>
Adjust the minimal page reporting order. The page
reporting is disabled when it exceeds (MAX_ORDER-1).
panic= [KNL] Kernel behaviour on panic: delay <timeout>
timeout > 0: seconds before rebooting
timeout = 0: wait forever

View File

@ -4,12 +4,17 @@
#include <linux/page_reporting.h>
#include <linux/gfp.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include "page_reporting.h"
#include "internal.h"
unsigned int page_reporting_order = MAX_ORDER;
module_param(page_reporting_order, uint, 0644);
MODULE_PARM_DESC(page_reporting_order, "Set page reporting order");
#define PAGE_REPORTING_DELAY (2 * HZ)
static struct page_reporting_dev_info __rcu *pr_dev_info __read_mostly;
@ -229,7 +234,7 @@ page_reporting_process_zone(struct page_reporting_dev_info *prdev,
/* Generate minimum watermark to be able to guarantee progress */
watermark = low_wmark_pages(zone) +
(PAGE_REPORTING_CAPACITY << PAGE_REPORTING_MIN_ORDER);
(PAGE_REPORTING_CAPACITY << page_reporting_order);
/*
* Cancel request if insufficient free memory or if we failed
@ -239,7 +244,7 @@ page_reporting_process_zone(struct page_reporting_dev_info *prdev,
return err;
/* Process each free list starting from lowest order/mt */
for (order = PAGE_REPORTING_MIN_ORDER; order < MAX_ORDER; order++) {
for (order = page_reporting_order; order < MAX_ORDER; order++) {
for (mt = 0; mt < MIGRATE_TYPES; mt++) {
/* We do not pull pages from the isolate free list */
if (is_migrate_isolate(mt))

View File

@ -10,10 +10,9 @@
#include <linux/pgtable.h>
#include <linux/scatterlist.h>
#define PAGE_REPORTING_MIN_ORDER pageblock_order
#ifdef CONFIG_PAGE_REPORTING
DECLARE_STATIC_KEY_FALSE(page_reporting_enabled);
extern unsigned int page_reporting_order;
void __page_reporting_notify(void);
static inline bool page_reported(struct page *page)
@ -38,7 +37,7 @@ static inline void page_reporting_notify_free(unsigned int order)
return;
/* Determine if we have crossed reporting threshold */
if (order < PAGE_REPORTING_MIN_ORDER)
if (order < page_reporting_order)
return;
/* This will add a few cycles, but should be called infrequently */