From cc7452b6dca384400960d40090a98d0eb920ab22 Mon Sep 17 00:00:00 2001 From: Rafael Aquini Date: Wed, 6 Aug 2014 16:06:38 -0700 Subject: [PATCH] mm: export NR_SHMEM via sysinfo(2) / si_meminfo() interfaces Historically, we exported shared pages to userspace via sysinfo(2) sharedram and /proc/meminfo's "MemShared" fields. With the advent of tmpfs, from kernel v2.4 onward, that old way for accounting shared mem was deemed inaccurate and we started to export a hard-coded 0 for sysinfo.sharedram. Later on, during the 2.6 timeframe, "MemShared" got re-introduced to /proc/meminfo re-branded as "Shmem", but we're still reporting sysinfo.sharedmem as that old hard-coded zero, which makes the "shared memory" report inconsistent across interfaces. This patch leverages the addition of explicit accounting for pages used by shmem/tmpfs -- "4b02108 mm: oom analysis: add shmem vmstat" -- in order to make the users of sysinfo(2) and si_meminfo*() friends aware of that vmstat entry and make them report it consistently across the interfaces, as well to make sysinfo(2) returned data consistent with our current API documentation states. Signed-off-by: Rafael Aquini Acked-by: Rik van Riel Cc: Mel Gorman Cc: Johannes Weiner Cc: KOSAKI Motohiro Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/node.c | 2 +- fs/proc/meminfo.c | 2 +- mm/page_alloc.c | 3 ++- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index 8f7ed9933a7c..c6d3ae05f1ca 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -126,7 +126,7 @@ static ssize_t node_read_meminfo(struct device *dev, nid, K(node_page_state(nid, NR_FILE_PAGES)), nid, K(node_page_state(nid, NR_FILE_MAPPED)), nid, K(node_page_state(nid, NR_ANON_PAGES)), - nid, K(node_page_state(nid, NR_SHMEM)), + nid, K(i.sharedram), nid, node_page_state(nid, NR_KERNEL_STACK) * THREAD_SIZE / 1024, nid, K(node_page_state(nid, NR_PAGETABLE)), diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c index 7445af0b1aa3..aa1eee06420f 100644 --- a/fs/proc/meminfo.c +++ b/fs/proc/meminfo.c @@ -168,7 +168,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v) K(global_page_state(NR_WRITEBACK)), K(global_page_state(NR_ANON_PAGES)), K(global_page_state(NR_FILE_MAPPED)), - K(global_page_state(NR_SHMEM)), + K(i.sharedram), K(global_page_state(NR_SLAB_RECLAIMABLE) + global_page_state(NR_SLAB_UNRECLAIMABLE)), K(global_page_state(NR_SLAB_RECLAIMABLE)), diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c1c6cb78e5ca..0987ac9f0a4e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3047,7 +3047,7 @@ static inline void show_node(struct zone *zone) void si_meminfo(struct sysinfo *val) { val->totalram = totalram_pages; - val->sharedram = 0; + val->sharedram = global_page_state(NR_SHMEM); val->freeram = global_page_state(NR_FREE_PAGES); val->bufferram = nr_blockdev_pages(); val->totalhigh = totalhigh_pages; @@ -3067,6 +3067,7 @@ void si_meminfo_node(struct sysinfo *val, int nid) for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) managed_pages += pgdat->node_zones[zone_type].managed_pages; val->totalram = managed_pages; + val->sharedram = node_page_state(nid, NR_SHMEM); val->freeram = node_page_state(nid, NR_FREE_PAGES); #ifdef CONFIG_HIGHMEM val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].managed_pages;