From 649751f368b392446bf930b07f01b34f17a4ce81 Mon Sep 17 00:00:00 2001
From: Mel Gorman <mgorman@suse.de>
Date: Thu, 19 Oct 2017 13:55:21 +0100
Subject: [PATCH] mm: remove cold parameter from free_hot_cold_page*
References: bsc#1060256
Patch-mainline: v4.15-rc1
Git-commit: 2d4894b5d2ae0fe1725ea7abd57b33bfbbe45492
Most callers users of free_hot_cold_page claim the pages being released
are cache hot. The exception is the page reclaim paths where it is likely
that enough pages will be freed in the near future that the per-cpu lists
are going to be recycled and the cache hotness information is lost. As no
one really cares about the hotness of pages being released to the
allocator, just ditch the parameter.
The APIs are renamed to indicate that it's no longer about hot/cold pages.
It should also be less confusing as there are subtle differences between
them. __free_pages drops a reference and frees a page when the refcount
reaches zero. free_hot_cold_page handled pages whose refcount was already
zero which is non-obvious from the name. free_unref_page should be more
obvious.
No performance impact is expected as the overhead is marginal. The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.
Link: http://lkml.kernel.org/r/20171018075952.10627-8-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
arch/powerpc/mm/mmu_context_book3s64.c | 2 +-
arch/powerpc/mm/pgtable_64.c | 2 +-
arch/sparc/mm/init_64.c | 2 +-
arch/tile/mm/homecache.c | 2 +-
include/linux/gfp.h | 4 ++--
include/trace/events/kmem.h | 11 ++++-------
mm/page_alloc.c | 29 ++++++++++++-----------------
mm/rmap.c | 2 +-
mm/swap.c | 4 ++--
mm/vmscan.c | 6 +++---
10 files changed, 28 insertions(+), 36 deletions(-)
diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c
index a75f63833284..7a562979b6e1 100644
--- a/arch/powerpc/mm/mmu_context_book3s64.c
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -210,7 +210,7 @@ static void destroy_pagetable_page(struct mm_struct *mm)
/* We allow PTE_FRAG_NR fragments from a PTE page */
if (page_ref_sub_and_test(page, PTE_FRAG_NR - count)) {
pgtable_page_dtor(page);
- free_hot_cold_page(page, 0);
+ free_unref_page(page);
}
}
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 0e74c50bb1c7..4b0908febd34 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -396,7 +396,7 @@ void pte_fragment_free(unsigned long *table, int kernel)
if (put_page_testzero(page)) {
if (!kernel)
pgtable_page_dtor(page);
- free_hot_cold_page(page, 0);
+ free_unref_page(page);
}
}
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index fed73f14aa49..0248a6fbc01c 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2890,7 +2890,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm,
if (!page)
return NULL;
if (!pgtable_page_ctor(page)) {
- free_hot_cold_page(page, 0);
+ free_unref_page(page);
return NULL;
}
return (pte_t *) page_address(page);
diff --git a/arch/tile/mm/homecache.c b/arch/tile/mm/homecache.c
index b51cc28acd0a..4432f31e8479 100644
--- a/arch/tile/mm/homecache.c
+++ b/arch/tile/mm/homecache.c
@@ -409,7 +409,7 @@ void __homecache_free_pages(struct page *page, unsigned int order)
if (put_page_testzero(page)) {
homecache_change_page_home(page, order, PAGE_HOME_HASH);
if (order == 0) {
- free_hot_cold_page(page, false);
+ free_unref_page(page);
} else {
init_page_count(page);
__free_pages(page, order);
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index a89d37e8b387..270631c84f51 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -511,8 +511,8 @@ void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
extern void __free_pages(struct page *page, unsigned int order);
extern void free_pages(unsigned long addr, unsigned int order);
-extern void free_hot_cold_page(struct page *page, bool cold);
-extern void free_hot_cold_page_list(struct list_head *list, bool cold);
+extern void free_unref_page(struct page *page);
+extern void free_unref_page_list(struct list_head *list);
struct page_frag_cache;
extern void __page_frag_cache_drain(struct page *page, unsigned int count);
diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
index 6b2e154fd23a..8e87ee321c33 100644
--- a/include/trace/events/kmem.h
+++ b/include/trace/events/kmem.h
@@ -171,24 +171,21 @@ TRACE_EVENT(mm_page_free,
TRACE_EVENT(mm_page_free_batched,
- TP_PROTO(struct page *page, int cold),
+ TP_PROTO(struct page *page),
- TP_ARGS(page, cold),
+ TP_ARGS(page),
TP_STRUCT__entry(
__field( unsigned long, pfn )
- __field( int, cold )
),
TP_fast_assign(
__entry->pfn = page_to_pfn(page);
- __entry->cold = cold;
),
- TP_printk("page=%p pfn=%lu order=0 cold=%d",
+ TP_printk("page=%p pfn=%lu order=0",
pfn_to_page(__entry->pfn),
- __entry->pfn,
- __entry->cold)
+ __entry->pfn)
);
TRACE_EVENT(mm_page_alloc,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 3db6d7c025b1..58118d59a277 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2551,7 +2551,7 @@ void mark_free_pages(struct zone *zone)
}
#endif /* CONFIG_PM */
-static bool free_hot_cold_page_prepare(struct page *page, unsigned long pfn)
+static bool free_unref_page_prepare(struct page *page, unsigned long pfn)
{
int migratetype;
@@ -2563,8 +2563,7 @@ static bool free_hot_cold_page_prepare(struct page *page, unsigned long pfn)
return true;
}
-static void free_hot_cold_page_commit(struct page *page, unsigned long pfn,
- bool cold)
+static void free_unref_page_commit(struct page *page, unsigned long pfn)
{
struct zone *zone = page_zone(page);
struct per_cpu_pages *pcp;
@@ -2589,10 +2588,7 @@ static void free_hot_cold_page_commit(struct page *page, unsigned long pfn,
}
pcp = &this_cpu_ptr(zone->pageset)->pcp;
- if (!cold)
- list_add(&page->lru, &pcp->lists[migratetype]);
- else
- list_add_tail(&page->lru, &pcp->lists[migratetype]);
+ list_add(&page->lru, &pcp->lists[migratetype]);
pcp->count++;
if (pcp->count >= pcp->high) {
unsigned long batch = READ_ONCE(pcp->batch);
@@ -2603,25 +2599,24 @@ static void free_hot_cold_page_commit(struct page *page, unsigned long pfn,
/*
* Free a 0-order page
- * cold == true ? free a cold page : free a hot page
*/
-void free_hot_cold_page(struct page *page, bool cold)
+void free_unref_page(struct page *page)
{
unsigned long flags;
unsigned long pfn = page_to_pfn(page);
- if (!free_hot_cold_page_prepare(page, pfn))
+ if (!free_unref_page_prepare(page, pfn))
return;
local_irq_save(flags);
- free_hot_cold_page_commit(page, pfn, cold);
+ free_unref_page_commit(page, pfn);
local_irq_restore(flags);
}
/*
* Free a list of 0-order pages
*/
-void free_hot_cold_page_list(struct list_head *list, bool cold)
+void free_unref_page_list(struct list_head *list)
{
struct page *page, *next;
unsigned long flags, pfn;
@@ -2629,7 +2624,7 @@ void free_hot_cold_page_list(struct list_head *list, bool cold)
/* Prepare pages for freeing */
list_for_each_entry_safe(page, next, list, lru) {
pfn = page_to_pfn(page);
- if (!free_hot_cold_page_prepare(page, pfn))
+ if (!free_unref_page_prepare(page, pfn))
list_del(&page->lru);
set_page_private(page, pfn);
}
@@ -2639,8 +2634,8 @@ void free_hot_cold_page_list(struct list_head *list, bool cold)
unsigned long pfn = page_private(page);
set_page_private(page, 0);
- trace_mm_page_free_batched(page, cold);
- free_hot_cold_page_commit(page, pfn, cold);
+ trace_mm_page_free_batched(page);
+ free_unref_page_commit(page, pfn);
}
local_irq_restore(flags);
}
@@ -4137,7 +4132,7 @@ void __free_pages(struct page *page, unsigned int order)
{
if (put_page_testzero(page)) {
if (order == 0)
- free_hot_cold_page(page, false);
+ free_unref_page(page);
else
__free_pages_ok(page, order);
}
@@ -4195,7 +4190,7 @@ void __page_frag_cache_drain(struct page *page, unsigned int count)
unsigned int order = compound_order(page);
if (order == 0)
- free_hot_cold_page(page, false);
+ free_unref_page(page);
else
__free_pages_ok(page, order);
}
diff --git a/mm/rmap.c b/mm/rmap.c
index 9835d19fe143..c82751a324d2 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1316,7 +1316,7 @@ void page_remove_rmap(struct page *page, bool compound)
* It would be tidy to reset the PageAnon mapping here,
* but that might overwrite a racing page_add_anon_rmap
* which increments mapcount after us but sets mapping
- * before us: so leave the reset to free_hot_cold_page,
+ * before us: so leave the reset to free_unref_page,
* and remember that it's only reliable while mapped.
* Leaving it set also helps swapoff to reinstate ptes
* faster for those pages still in swapcache.
diff --git a/mm/swap.c b/mm/swap.c
index 56ff313dd516..5ebc0d8c0ea2 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -76,7 +76,7 @@ static void __page_cache_release(struct page *page)
static void __put_single_page(struct page *page)
{
__page_cache_release(page);
- free_hot_cold_page(page, false);
+ free_unref_page(page);
}
static void __put_compound_page(struct page *page)
@@ -800,7 +800,7 @@ void release_pages(struct page **pages, int nr)
spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags);
mem_cgroup_uncharge_list(&pages_to_free);
- free_hot_cold_page_list(&pages_to_free, 0);
+ free_unref_page_list(&pages_to_free);
}
EXPORT_SYMBOL(release_pages);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 8ad39bbc79e6..e07806299985 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1305,7 +1305,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
mem_cgroup_uncharge_list(&free_pages);
try_to_unmap_flush();
- free_hot_cold_page_list(&free_pages, true);
+ free_unref_page_list(&free_pages);
list_splice(&ret_pages, page_list);
count_vm_events(PGACTIVATE, pgactivate);
@@ -1764,7 +1764,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
spin_unlock_irq(&pgdat->lru_lock);
mem_cgroup_uncharge_list(&page_list);
- free_hot_cold_page_list(&page_list, true);
+ free_unref_page_list(&page_list);
/*
* If reclaim is isolating dirty pages under writeback, it implies
@@ -1999,7 +1999,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
spin_unlock_irq(&pgdat->lru_lock);
mem_cgroup_uncharge_list(&l_hold);
- free_hot_cold_page_list(&l_hold, true);
+ free_unref_page_list(&l_hold);
trace_mm_vmscan_lru_shrink_active(pgdat->node_id, nr_taken, nr_activate,
nr_deactivate, nr_rotated, sc->priority, file);
}