[PATCHv5 11/12] mm/vmstat: Add counter for memory accepting

Kirill A. Shutemov
2022-04-25T03:40:15Z

The counter increased every time kernel accepts a memory region.

The counter allows to see if memory acceptation is still ongoing and
contributes to memory allocation latency.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
arch/x86/mm/unaccepted_memory.c | 1 +
include/linux/vm_event_item.h | 3 +++
mm/vmstat.c | 3 +++
3 files changed, 7 insertions(+)

diff --git a/arch/x86/mm/unaccepted_memory.c b/arch/x86/mm/unaccepted_memory.c
index de0790af1824..65cd49b93c50 100644
--- a/arch/x86/mm/unaccepted_memory.c
+++ b/arch/x86/mm/unaccepted_memory.c
@@ -38,6 +38,7 @@ void accept_memory(phys_addr_t start, phys_addr_t end)
}

bitmap_clear(unaccepted_memory, range_start, len);
+ count_vm_events(ACCEPT_MEMORY, len * PMD_SIZE / PAGE_SIZE);
}
spin_unlock_irqrestore(&unaccepted_memory_lock, flags);
}
diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
index 16a0a4fd000b..6a468164a2f9 100644
--- a/include/linux/vm_event_item.h
+++ b/include/linux/vm_event_item.h
@@ -136,6 +136,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
#ifdef CONFIG_X86
DIRECT_MAP_LEVEL2_SPLIT,
DIRECT_MAP_LEVEL3_SPLIT,
+#endif
+#ifdef CONFIG_UNACCEPTED_MEMORY
+ ACCEPT_MEMORY,
#endif
NR_VM_EVENT_ITEMS
};
diff --git a/mm/vmstat.c b/mm/vmstat.c
index b75b1a64b54c..4c9197f32406 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1397,6 +1397,9 @@ const char * const vmstat_text[] = {
"direct_map_level2_splits",
"direct_map_level3_splits",
#endif
+#ifdef CONFIG_UNACCEPTED_MEMORY
+ "accept_memory",
+#endif
#endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */
};
#endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA || CONFIG_MEMCG */
--
2.35.1