diff options
author | Konstantin Khlebnikov <koct9i@gmail.com> | 2016-01-15 02:22:07 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-15 03:00:49 +0300 |
commit | 84638335900f1995495838fe1bd4870c43ec1f67 (patch) | |
tree | 8983e891fcf8320408c8ff2c6137f27ce553ba5a /fs/proc/task_mmu.c | |
parent | d30b5545bdcf802ffc24ec7dbc6dc4036f6e3820 (diff) | |
download | linux-84638335900f1995495838fe1bd4870c43ec1f67.tar.xz |
mm: rework virtual memory accounting
When inspecting a vague code inside prctl(PR_SET_MM_MEM) call (which
testing the RLIMIT_DATA value to figure out if we're allowed to assign
new @start_brk, @brk, @start_data, @end_data from mm_struct) it's been
commited that RLIMIT_DATA in a form it's implemented now doesn't do
anything useful because most of user-space libraries use mmap() syscall
for dynamic memory allocations.
Linus suggested to convert RLIMIT_DATA rlimit into something suitable
for anonymous memory accounting. But in this patch we go further, and
the changes are bundled together as:
* keep vma counting if CONFIG_PROC_FS=n, will be used for limits
* replace mm->shared_vm with better defined mm->data_vm
* account anonymous executable areas as executable
* account file-backed growsdown/up areas as stack
* drop struct file* argument from vm_stat_account
* enforce RLIMIT_DATA for size of data areas
This way code looks cleaner: now code/stack/data classification depends
only on vm_flags state:
VM_EXEC & ~VM_WRITE -> code (VmExe + VmLib in proc)
VM_GROWSUP | VM_GROWSDOWN -> stack (VmStk)
VM_WRITE & ~VM_SHARED & !stack -> data (VmData)
The rest (VmSize - VmData - VmStk - VmExe - VmLib) could be called
"shared", but that might be strange beast like readonly-private or VM_IO
area.
- RLIMIT_AS limits whole address space "VmSize"
- RLIMIT_STACK limits stack "VmStk" (but each vma individually)
- RLIMIT_DATA now limits "VmData"
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Kees Cook <keescook@google.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/proc/task_mmu.c')
-rw-r--r-- | fs/proc/task_mmu.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 46d9619d0aea..a353b4c6e86e 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -23,7 +23,7 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) { - unsigned long data, text, lib, swap, ptes, pmds, anon, file, shmem; + unsigned long text, lib, swap, ptes, pmds, anon, file, shmem; unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; anon = get_mm_counter(mm, MM_ANONPAGES); @@ -44,7 +44,6 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) if (hiwater_rss < mm->hiwater_rss) hiwater_rss = mm->hiwater_rss; - data = mm->total_vm - mm->shared_vm - mm->stack_vm; text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; swap = get_mm_counter(mm, MM_SWAPENTS); @@ -76,7 +75,7 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) anon << (PAGE_SHIFT-10), file << (PAGE_SHIFT-10), shmem << (PAGE_SHIFT-10), - data << (PAGE_SHIFT-10), + mm->data_vm << (PAGE_SHIFT-10), mm->stack_vm << (PAGE_SHIFT-10), text, lib, ptes >> 10, pmds >> 10, @@ -97,7 +96,7 @@ unsigned long task_statm(struct mm_struct *mm, get_mm_counter(mm, MM_SHMEMPAGES); *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> PAGE_SHIFT; - *data = mm->total_vm - mm->shared_vm; + *data = mm->data_vm + mm->stack_vm; *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); return mm->total_vm; } |