From: Joonsoo Kim <js1304@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
Joonsoo Kim <js1304@gmail.com>
Subject: [PATCH 4/5] mm, highmem: makes flush_all_zero_pkmaps() return index of last flushed entry
Date: Mon, 29 Oct 2012 04:12:55 +0900 [thread overview]
Message-ID: <1351451576-2611-5-git-send-email-js1304@gmail.com> (raw)
In-Reply-To: <1351451576-2611-1-git-send-email-js1304@gmail.com>
In current code, after flush_all_zero_pkmaps() is invoked,
then re-iterate all pkmaps. It can be optimized if flush_all_zero_pkmaps()
return index of flushed entry. With this index,
we can immediately map highmem page to virtual address represented by index.
So change return type of flush_all_zero_pkmaps()
and return index of last flushed entry.
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index ef788b5..0683869 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -32,6 +32,7 @@ static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
#ifdef CONFIG_HIGHMEM
#include <asm/highmem.h>
+#define PKMAP_INDEX_INVAL (-1)
/* declarations for linux/mm/highmem.c */
unsigned int nr_free_highpages(void);
diff --git a/mm/highmem.c b/mm/highmem.c
index 731cf9a..65beb9a 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -106,10 +106,10 @@ struct page *kmap_to_page(void *vaddr)
return virt_to_page(addr);
}
-static void flush_all_zero_pkmaps(void)
+static int flush_all_zero_pkmaps(void)
{
int i;
- int need_flush = 0;
+ int index = PKMAP_INDEX_INVAL;
flush_cache_kmaps();
@@ -141,10 +141,12 @@ static void flush_all_zero_pkmaps(void)
&pkmap_page_table[i]);
set_page_address(page, NULL);
- need_flush = 1;
+ index = i;
}
- if (need_flush)
+ if (index != PKMAP_INDEX_INVAL)
flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
+
+ return index;
}
/**
@@ -160,6 +162,7 @@ void kmap_flush_unused(void)
static inline unsigned long map_new_virtual(struct page *page)
{
unsigned long vaddr;
+ int index = PKMAP_INDEX_INVAL;
int count;
start:
@@ -168,40 +171,45 @@ start:
for (;;) {
last_pkmap_nr = (last_pkmap_nr + 1) & LAST_PKMAP_MASK;
if (!last_pkmap_nr) {
- flush_all_zero_pkmaps();
- count = LAST_PKMAP;
+ index = flush_all_zero_pkmaps();
+ if (index != PKMAP_INDEX_INVAL)
+ break; /* Found a usable entry */
}
- if (!pkmap_count[last_pkmap_nr])
+ if (!pkmap_count[last_pkmap_nr]) {
+ index = last_pkmap_nr;
break; /* Found a usable entry */
- if (--count)
- continue;
-
- /*
- * Sleep for somebody else to unmap their entries
- */
- {
- DECLARE_WAITQUEUE(wait, current);
-
- __set_current_state(TASK_UNINTERRUPTIBLE);
- add_wait_queue(&pkmap_map_wait, &wait);
- unlock_kmap();
- schedule();
- remove_wait_queue(&pkmap_map_wait, &wait);
- lock_kmap();
-
- /* Somebody else might have mapped it while we slept */
- if (page_address(page))
- return (unsigned long)page_address(page);
-
- /* Re-start */
- goto start;
}
+ if (--count == 0)
+ break;
}
- vaddr = PKMAP_ADDR(last_pkmap_nr);
+
+ /*
+ * Sleep for somebody else to unmap their entries
+ */
+ if (index == PKMAP_INDEX_INVAL) {
+ DECLARE_WAITQUEUE(wait, current);
+
+ __set_current_state(TASK_UNINTERRUPTIBLE);
+ add_wait_queue(&pkmap_map_wait, &wait);
+ unlock_kmap();
+ schedule();
+ remove_wait_queue(&pkmap_map_wait, &wait);
+ lock_kmap();
+
+ /* Somebody else might have mapped it while we slept */
+ vaddr = (unsigned long)page_address(page);
+ if (vaddr)
+ return vaddr;
+
+ /* Re-start */
+ goto start;
+ }
+
+ vaddr = PKMAP_ADDR(index);
set_pte_at(&init_mm, vaddr,
- &(pkmap_page_table[last_pkmap_nr]), mk_pte(page, kmap_prot));
+ &(pkmap_page_table[index]), mk_pte(page, kmap_prot));
- pkmap_count[last_pkmap_nr] = 1;
+ pkmap_count[index] = 1;
set_page_address(page, (void *)vaddr);
return vaddr;
--
1.7.9.5
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next prev parent reply other threads:[~2012-10-28 19:15 UTC|newest]
Thread overview: 95+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <Yes>
2012-07-16 16:14 ` [PATCH 1/3] mm: correct return value of migrate_pages() Joonsoo Kim
2012-07-16 16:14 ` [PATCH 2/3] mm: fix possible incorrect return value of migrate_pages() syscall Joonsoo Kim
2012-07-16 17:26 ` Christoph Lameter
2012-07-16 17:40 ` Michal Nazarewicz
2012-07-16 17:59 ` JoonSoo Kim
2012-07-17 13:02 ` Michal Nazarewicz
2012-07-16 16:14 ` [PATCH 3/3] mm: fix return value in __alloc_contig_migrate_range() Joonsoo Kim
2012-07-16 17:29 ` Christoph Lameter
2012-07-16 17:40 ` Michal Nazarewicz
2012-07-16 18:40 ` JoonSoo Kim
2012-07-17 13:16 ` Michal Nazarewicz
2012-07-16 17:14 ` [PATCH 4] mm: fix possible incorrect return value of move_pages() syscall Joonsoo Kim
2012-07-16 17:30 ` Christoph Lameter
2012-07-16 17:23 ` [PATCH 1/3] mm: correct return value of migrate_pages() Christoph Lameter
2012-07-16 17:32 ` JoonSoo Kim
2012-07-16 17:37 ` Christoph Lameter
2012-07-16 17:40 ` Michal Nazarewicz
2012-07-16 17:57 ` JoonSoo Kim
2012-07-16 18:05 ` Christoph Lameter
2012-07-17 12:33 ` [PATCH 1/4 v2] mm: correct return value of migrate_pages() and migrate_huge_pages() Joonsoo Kim
2012-07-17 12:33 ` [PATCH 2/4 v2] mm: fix possible incorrect return value of migrate_pages() syscall Joonsoo Kim
2012-07-17 14:28 ` Christoph Lameter
2012-07-17 15:41 ` JoonSoo Kim
2012-07-17 12:33 ` [PATCH 3/4 v2] mm: fix return value in __alloc_contig_migrate_range() Joonsoo Kim
2012-07-17 13:25 ` Michal Nazarewicz
2012-07-17 15:45 ` JoonSoo Kim
2012-07-17 15:49 ` [PATCH 3/4 v3] " Joonsoo Kim
2012-07-17 12:33 ` [PATCH 4/4 v2] mm: fix possible incorrect return value of move_pages() syscall Joonsoo Kim
2012-07-27 17:55 ` [RESEND PATCH 1/4 v3] mm: correct return value of migrate_pages() and migrate_huge_pages() Joonsoo Kim
2012-07-27 17:55 ` [RESEND PATCH 2/4 v3] mm: fix possible incorrect return value of migrate_pages() syscall Joonsoo Kim
2012-07-27 20:57 ` Christoph Lameter
2012-07-28 6:16 ` JoonSoo Kim
2012-07-30 19:30 ` Christoph Lameter
2012-07-27 17:55 ` [RESEND PATCH 3/4 v3] mm: fix return value in __alloc_contig_migrate_range() Joonsoo Kim
2012-07-27 17:55 ` [RESEND PATCH 4/4 v3] mm: fix possible incorrect return value of move_pages() syscall Joonsoo Kim
2012-07-27 20:54 ` Christoph Lameter
2012-07-28 6:09 ` JoonSoo Kim
2012-07-30 19:29 ` Christoph Lameter
2012-07-31 3:34 ` JoonSoo Kim
2012-07-31 14:04 ` Christoph Lameter
2012-08-01 5:15 ` Michael Kerrisk
2012-08-01 18:00 ` Christoph Lameter
2012-08-02 5:52 ` Michael Kerrisk
2012-08-24 16:05 ` [PATCH 1/2] slub: rename cpu_partial to max_cpu_object Joonsoo Kim
2012-08-24 16:05 ` [PATCH 2/2] slub: correct the calculation of the number of cpu objects in get_partial_node Joonsoo Kim
2012-08-24 16:15 ` Christoph Lameter
2012-08-24 16:28 ` JoonSoo Kim
2012-08-24 16:31 ` Christoph Lameter
2012-08-24 16:40 ` JoonSoo Kim
2012-08-24 16:12 ` [PATCH 1/2] slub: rename cpu_partial to max_cpu_object Christoph Lameter
2012-08-25 14:11 ` [PATCH 1/2] slab: do ClearSlabPfmemalloc() for all pages of slab Joonsoo Kim
2012-08-25 14:11 ` [PATCH 2/2] slab: fix starting index for finding another object Joonsoo Kim
2012-09-03 10:08 ` [PATCH 1/2] slab: do ClearSlabPfmemalloc() for all pages of slab Mel Gorman
2012-10-20 15:48 ` [PATCH for-v3.7 1/2] slub: optimize poorly inlined kmalloc* functions Joonsoo Kim
2012-10-20 15:48 ` [PATCH for-v3.7 2/2] slub: optimize kmalloc* inlining for GFP_DMA Joonsoo Kim
2012-10-22 14:31 ` Christoph Lameter
2012-10-23 2:29 ` JoonSoo Kim
2012-10-23 6:16 ` Eric Dumazet
2012-10-23 16:12 ` JoonSoo Kim
2012-10-24 8:05 ` [PATCH for-v3.7 1/2] slub: optimize poorly inlined kmalloc* functions Pekka Enberg
2012-10-24 13:36 ` Christoph Lameter
2012-10-28 19:12 ` [PATCH 0/5] minor clean-up and optimize highmem related code Joonsoo Kim
2012-10-28 19:12 ` [PATCH 1/5] mm, highmem: use PKMAP_NR() to calculate an index of pkmap Joonsoo Kim
2012-10-29 1:48 ` Minchan Kim
2012-10-28 19:12 ` [PATCH 2/5] mm, highmem: remove useless pool_lock Joonsoo Kim
2012-10-29 1:52 ` Minchan Kim
2012-10-30 21:31 ` Andrew Morton
2012-10-31 5:14 ` Minchan Kim
2012-10-31 15:01 ` JoonSoo Kim
2012-10-28 19:12 ` [PATCH 3/5] mm, highmem: remove page_address_pool list Joonsoo Kim
2012-10-29 1:57 ` Minchan Kim
2012-10-28 19:12 ` Joonsoo Kim [this message]
2012-10-29 2:06 ` [PATCH 4/5] mm, highmem: makes flush_all_zero_pkmaps() return index of last flushed entry Minchan Kim
2012-10-29 13:12 ` JoonSoo Kim
2012-10-28 19:12 ` [PATCH 5/5] mm, highmem: get virtual address of the page using PKMAP_ADDR() Joonsoo Kim
2012-10-29 2:09 ` Minchan Kim
2012-10-29 2:12 ` [PATCH 0/5] minor clean-up and optimize highmem related code Minchan Kim
2012-10-29 13:15 ` JoonSoo Kim
2012-10-31 17:11 ` JoonSoo Kim
2012-10-31 16:56 ` [PATCH v2 " Joonsoo Kim
2012-10-31 16:56 ` [PATCH v2 1/5] mm, highmem: use PKMAP_NR() to calculate an index of pkmap Joonsoo Kim
2012-10-31 16:56 ` [PATCH v2 2/5] mm, highmem: remove useless pool_lock Joonsoo Kim
2012-10-31 16:56 ` [PATCH v2 3/5] mm, highmem: remove page_address_pool list Joonsoo Kim
2012-10-31 16:56 ` [PATCH v2 4/5] mm, highmem: makes flush_all_zero_pkmaps() return index of first flushed entry Joonsoo Kim
2012-11-01 5:03 ` Minchan Kim
2012-11-02 19:07 ` JoonSoo Kim
2012-11-02 22:42 ` Minchan Kim
2012-11-13 0:30 ` JoonSoo Kim
2012-11-13 12:49 ` Minchan Kim
2012-11-13 14:12 ` JoonSoo Kim
2012-11-13 15:01 ` Minchan Kim
2012-11-14 17:09 ` JoonSoo Kim
2012-11-19 23:46 ` Minchan Kim
2012-11-27 15:01 ` JoonSoo Kim
2012-10-31 16:56 ` [PATCH v2 5/5] mm, highmem: get virtual address of the page using PKMAP_ADDR() Joonsoo Kim
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