diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 75988ba26a51..b5aee7838a00 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -176,6 +176,7 @@ read the file /proc/PID/status:
CapBnd: ffffffffffffffff
voluntary_ctxt_switches: 0
nonvoluntary_ctxt_switches: 1
+ Stack usage: 12 kB
This shows you nearly the same information you would get if you viewed it with
the ps command. In fact, ps uses the proc file system to obtain its
@@ -229,6 +230,7 @@ Table 1-2: Contents of the statm files (as of 2.6.30-rc7)
Mems_allowed_list Same as previous, but in "list format"
voluntary_ctxt_switches number of voluntary context switches
nonvoluntary_ctxt_switches number of non voluntary context switches
+ Stack usage: stack usage high water mark (round up to page size)
..............................................................................
Table 1-3: Contents of the statm files (as of 2.6.8-rc3)
@@ -307,7 +309,7 @@ address perms offset dev inode pathname
08049000-0804a000 rw-p 00001000 03:00 8312 /opt/test
0804a000-0806b000 rw-p 00000000 00:00 0 [heap]
a7cb1000-a7cb2000 ---p 00000000 00:00 0
-a7cb2000-a7eb2000 rw-p 00000000 00:00 0
+a7cb2000-a7eb2000 rw-p 00000000 00:00 0 [threadstack:001ff4b4]
a7eb2000-a7eb3000 ---p 00000000 00:00 0
a7eb3000-a7ed5000 rw-p 00000000 00:00 0
a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6
@@ -343,6 +345,7 @@ is not associated with a file:
[stack] = the stack of the main process
[vdso] = the "virtual dynamic shared object",
the kernel system call handler
+ [threadstack:xxxxxxxx] = the stack of the thread, xxxxxxxx is the stack size
or if empty, the mapping is anonymous.
diff --git a/fs/exec.c b/fs/exec.c
index 69bb9d899791..5c833c18d0d4 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1357,6 +1357,8 @@ int do_execve(char * filename,
if (retval < 0)
goto out;
+ current->stack_start = current->mm->start_stack;
+
/* execve succeeded */
current->fs->in_exec = 0;
current->in_execve = 0;
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 725a650bbbb8..0c6bc602e6c4 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -82,6 +82,7 @@
#include <linux/pid_namespace.h>
#include <linux/ptrace.h>
#include <linux/tracehook.h>
+#include <linux/swapops.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
@@ -321,6 +322,87 @@ static inline void task_context_switch_counts(struct seq_file *m,
p->nivcsw);
}
+struct stack_stats {
+ struct vm_area_struct *vma;
+ unsigned long startpage;
+ unsigned long usage;
+};
+
+static int stack_usage_pte_range(pmd_t *pmd, unsigned long addr,
+ unsigned long end, struct mm_walk *walk)
+{
+ struct stack_stats *ss = walk->private;
+ struct vm_area_struct *vma = ss->vma;
+ pte_t *pte, ptent;
+ spinlock_t *ptl;
+ int ret = 0;
+
+ pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+ for (; addr != end; pte++, addr += PAGE_SIZE) {
+ ptent = *pte;
+
+#ifdef CONFIG_STACK_GROWSUP
+ if (pte_present(ptent) || is_swap_pte(ptent))
+ ss->usage = addr - ss->startpage + PAGE_SIZE;
+#else
+ if (pte_present(ptent) || is_swap_pte(ptent)) {
+ ss->usage = ss->startpage - addr + PAGE_SIZE;
+ pte++;
+ ret = 1;
+ break;
+ }
+#endif
+ }
+ pte_unmap_unlock(pte - 1, ptl);
+ cond_resched();
+ return ret;
+}
+
+static inline unsigned long get_stack_usage_in_bytes(struct vm_area_struct *vma,
+ struct task_struct *task)
+{
+ struct stack_stats ss;
+ struct mm_walk stack_walk = {
+ .pmd_entry = stack_usage_pte_range,
+ .mm = vma->vm_mm,
+ .private = &ss,
+ };
+
+ if (!vma->vm_mm || is_vm_hugetlb_page(vma))
+ return 0;
+
+ ss.vma = vma;
+ ss.startpage = task->stack_start & PAGE_MASK;
+ ss.usage = 0;
+
+#ifdef CONFIG_STACK_GROWSUP
+ walk_page_range(KSTK_ESP(task) & PAGE_MASK, vma->vm_end,
+ &stack_walk);
+#else
+ walk_page_range(vma->vm_start, (KSTK_ESP(task) & PAGE_MASK) + PAGE_SIZE,
+ &stack_walk);
+#endif
+ return ss.usage;
+}
+
+static inline void task_show_stack_usage(struct seq_file *m,
+ struct task_struct *task)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = get_task_mm(task);
+
+ if (mm) {
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, task->stack_start);
+ if (vma)
+ seq_printf(m, "Stack usage:\t%lu kB\n",
+ get_stack_usage_in_bytes(vma, task) >> 10);
+
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+ }
+}
+
int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task)
{
@@ -340,6 +422,7 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
task_show_regs(m, task);
#endif
task_context_switch_counts(m, task);
+ task_show_stack_usage(m, task);
return 0;
}
@@ -481,7 +564,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
rsslim,
mm ? mm->start_code : 0,
mm ? mm->end_code : 0,
- (permitted && mm) ? mm->start_stack : 0,
+ (permitted) ? task->stack_start : 0,
esp,
eip,
/* The signal information here is obsolete.
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 366b1017a4f1..2a1bef9203c6 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -243,6 +243,25 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
} else if (vma->vm_start <= mm->start_stack &&
vma->vm_end >= mm->start_stack) {
name = "[stack]";
+ } else {
+ unsigned long stack_start;
+ struct proc_maps_private *pmp;
+
+ pmp = m->private;
+ stack_start = pmp->task->stack_start;
+
+ if (vma->vm_start <= stack_start &&
+ vma->vm_end >= stack_start) {
+ pad_len_spaces(m, len);
+ seq_printf(m,
+ "[threadstack:%08lx]",
+#ifdef CONFIG_STACK_GROWSUP
+ vma->vm_end - stack_start
+#else
+ stack_start - vma->vm_start
+#endif
+ );
+ }
}
} else {
name = "[vdso]";
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6448bbc6406b..3cbc6c0be666 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1529,6 +1529,7 @@ struct task_struct {
/* bitmask of trace recursion */
unsigned long trace_recursion;
#endif /* CONFIG_TRACING */
+ unsigned long stack_start;
};
/* Future-safe accessor for struct task_struct's cpus_allowed. */
diff --git a/kernel/fork.c b/kernel/fork.c
index 7cf45812ce84..8f45b0ebdda7 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1095,6 +1095,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->bts = NULL;
+ p->stack_start = stack_start;
+
/* Perform scheduler related setup. Assign this task to a CPU. */
sched_fork(p, clone_flags);
diff --git a/mm/Makefile b/mm/Makefile
index 728a9fde49d1..88193d73cd1a 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -11,10 +11,10 @@ obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
maccess.o page_alloc.o page-writeback.o \
readahead.o swap.o truncate.o vmscan.o shmem.o \
prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \
- page_isolation.o mm_init.o mmu_context.o $(mmu-y)
+ page_isolation.o mm_init.o mmu_context.o \
+ pagewalk.o $(mmu-y)
obj-y += init-mm.o
-obj-$(CONFIG_PROC_PAGE_MONITOR) += pagewalk.o
obj-$(CONFIG_BOUNCE) += bounce.o
obj-$(CONFIG_SWAP) += page_io.o swap_state.o swapfile.o thrash.o
obj-$(CONFIG_HAS_DMA) += dmapool.o