Commit fc3ba692 authored by Miklos Szeredi's avatar Miklos Szeredi Committed by Linus Torvalds
Browse files

mm: Add NR_WRITEBACK_TEMP counter 



Fuse will use temporary buffers to write back dirty data from memory mappings
(normal writes are done synchronously).  This is needed, because there cannot
be any guarantee about the time in which a write will complete.

By using temporary buffers, from the MM's point if view the page is written
back immediately.  If the writeout was due to memory pressure, this
effectively migrates data from a full zone to a less full zone.

This patch adds a new counter (NR_WRITEBACK_TEMP) for the number of pages used
as temporary buffers.

[Lee.Schermerhorn@hp.com: add vmstat_text for NR_WRITEBACK_TEMP]
Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: default avatarLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent dd5656e5

drivers/base/node.c

+2 −0
Original line number Diff line number Diff line
@@ -77,6 +77,7 @@ static ssize_t node_read_meminfo(struct sys_device * dev, char * buf) 
		       "Node %d PageTables:   %8lu kB\n"

		       "Node %d NFS_Unstable: %8lu kB\n"

		       "Node %d Bounce:       %8lu kB\n"

		       "Node %d WritebackTmp: %8lu kB\n"

		       "Node %d Slab:         %8lu kB\n"

		       "Node %d SReclaimable: %8lu kB\n"

		       "Node %d SUnreclaim:   %8lu kB\n",
@@ -99,6 +100,7 @@ static ssize_t node_read_meminfo(struct sys_device * dev, char * buf) 
		       nid, K(node_page_state(nid, NR_PAGETABLE)),

		       nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),

		       nid, K(node_page_state(nid, NR_BOUNCE)),

		       nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),

		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +

				node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),

		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),

fs/proc/proc_misc.c

+2 −0
Original line number Diff line number Diff line
@@ -179,6 +179,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off, 
		"PageTables:   %8lu kB\n"

		"NFS_Unstable: %8lu kB\n"

		"Bounce:       %8lu kB\n"

		"WritebackTmp: %8lu kB\n"

		"CommitLimit:  %8lu kB\n"

		"Committed_AS: %8lu kB\n"

		"VmallocTotal: %8lu kB\n"
@@ -210,6 +211,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off, 
		K(global_page_state(NR_PAGETABLE)),

		K(global_page_state(NR_UNSTABLE_NFS)),

		K(global_page_state(NR_BOUNCE)),

		K(global_page_state(NR_WRITEBACK_TEMP)),

		K(allowed),

		K(committed),

		(unsigned long)VMALLOC_TOTAL >> 10,

include/linux/mmzone.h

+1 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ enum zone_stat_item { 
	NR_UNSTABLE_NFS,	/* NFS unstable pages */

	NR_BOUNCE,

	NR_VMSCAN_WRITE,

	NR_WRITEBACK_TEMP,	/* Writeback using temporary buffers */

#ifdef CONFIG_NUMA

	NUMA_HIT,		/* allocated in intended node */

	NUMA_MISS,		/* allocated in non intended node */

mm/page-writeback.c

+2 −1
Original line number Diff line number Diff line
@@ -211,7 +211,8 @@ clip_bdi_dirty_limit(struct backing_dev_info *bdi, long dirty, long *pbdi_dirty) 
	avail_dirty = dirty -

		(global_page_state(NR_FILE_DIRTY) +

		 global_page_state(NR_WRITEBACK) +

		 global_page_state(NR_UNSTABLE_NFS));

		 global_page_state(NR_UNSTABLE_NFS) +

		 global_page_state(NR_WRITEBACK_TEMP));



	if (avail_dirty < 0)

		avail_dirty = 0;

mm/vmstat.c

+1 −0
Original line number Diff line number Diff line
@@ -612,6 +612,7 @@ static const char * const vmstat_text[] = { 
	"nr_unstable",

	"nr_bounce",

	"nr_vmscan_write",

	"nr_writeback_temp",



#ifdef CONFIG_NUMA

	"numa_hit",

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