Detailed Stack Information Patch [1/3]

Stefani Seibold
2009-03-31T15:21:03Z

diff -u -N -r linux-2.6.29.orig/fs/exec.c linux-2.6.29/fs/exec.c
--- linux-2.6.29.orig/fs/exec.c 2009-03-24 00:12:14.000000000 +0100
+++ linux-2.6.29/fs/exec.c 2009-03-31 16:02:55.000000000 +0200
@@ -1336,6 +1336,10 @@
if (retval < 0)
goto out;

+#ifdef CONFIG_PROC_STACK
+ current->stack_start = current->mm->start_stack;
+#endif
+
/* execve succeeded */
mutex_unlock(&current->cred_exec_mutex);
acct_update_integrals(current);
diff -u -N -r linux-2.6.29.orig/fs/proc/array.c linux-2.6.29/fs/proc/array.c
--- linux-2.6.29.orig/fs/proc/array.c 2009-03-24 00:12:14.000000000 +0100
+++ linux-2.6.29/fs/proc/array.c 2009-03-31 16:00:19.000000000 +0200
@@ -320,6 +320,25 @@
p->nivcsw);
}

+#ifdef CONFIG_PROC_STACK
+static inline void task_show_stack_usage(struct seq_file *m,
+ struct task_struct *p)
+{
+ unsigned long cur_stack;
+ unsigned long base_page;
+
+ base_page = KSTK_ESP(p) >> PAGE_SHIFT;
+
+#ifdef CONFIG_STACK_GROWSUP
+ cur_stack = base_page-(p->stack_start >> PAGE_SHIFT);
+#else
+ cur_stack = (p->stack_start >> PAGE_SHIFT)-base_page;
+#endif
+ seq_printf(m, "stack usage:\t%lu kB\n",
+ (cur_stack + 1) << (PAGE_SHIFT-10));
+}
+#endif
+
int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task)
{
@@ -339,6 +358,9 @@
task_show_regs(m, task);
#endif
task_context_switch_counts(m, task);
+#ifdef CONFIG_PROC_STACK
+ task_show_stack_usage(m, task);
+#endif
return 0;
}

diff -u -N -r linux-2.6.29.orig/fs/proc/task_mmu.c linux-2.6.29/fs/proc/task_mmu.c
--- linux-2.6.29.orig/fs/proc/task_mmu.c 2009-03-24 00:12:14.000000000 +0100
+++ linux-2.6.29/fs/proc/task_mmu.c 2009-03-31 16:00:19.000000000 +0200
@@ -240,6 +240,18 @@
} else if (vma->vm_start <= mm->start_stack &&
vma->vm_end >= mm->start_stack) {
name = "[stack]";
+#ifdef CONFIG_PROC_STACK
+ } else {
+ unsigned long stack_start;
+
+ stack_start =
+ ((struct proc_maps_private *)
+ m->private)->task->stack_start;
+
+ if (vma->vm_start <= stack_start &&
+ vma->vm_end >= stack_start)
+ name="[thread stack]";
+#endif
}
} else {
name = "[vdso]";
diff -u -N -r linux-2.6.29.orig/include/linux/sched.h linux-2.6.29/include/linux/sched.h
--- linux-2.6.29.orig/include/linux/sched.h 2009-03-24 00:12:14.000000000 +0100
+++ linux-2.6.29/include/linux/sched.h 2009-03-31 16:00:45.000000000 +0200
@@ -1417,6 +1417,9 @@
/* state flags for use by tracers */
unsigned long trace;
#endif
+#ifdef CONFIG_PROC_STACK
+ unsigned long stack_start;
+#endif
};

/* Future-safe accessor for struct task_struct's cpus_allowed. */
diff -u -N -r linux-2.6.29.orig/init/Kconfig linux-2.6.29/init/Kconfig
--- linux-2.6.29.orig/init/Kconfig 2009-03-24 00:12:14.000000000 +0100
+++ linux-2.6.29/init/Kconfig 2009-03-31 16:00:19.000000000 +0200
@@ -952,6 +952,18 @@

source "arch/Kconfig"

+config PROC_STACK
+ default y
+ depends on PROC_FS && MMU
+ bool "Enable /proc/<pid> stack monitoring" if EMBEDDED
+ help
+ This enables monitoring of process and thread stack utilization.
+
+ The /proc/pid/maps, /proc/pid/smaps, /proc/pid/status and the
+ /proc/pid/task/pid pedants will be extended by the stack information.
+ Disabling these interfaces will reduce the size of the kernel by
+ approximately 1kb.
+
endmenu # General setup

config HAVE_GENERIC_DMA_COHERENT
diff -u -N -r linux-2.6.29.orig/kernel/fork.c linux-2.6.29/kernel/fork.c
--- linux-2.6.29.orig/kernel/fork.c 2009-03-24 00:12:14.000000000 +0100
+++ linux-2.6.29/kernel/fork.c 2009-03-31 16:00:19.000000000 +0200
@@ -1098,6 +1098,11 @@
if (unlikely(current->ptrace))
ptrace_fork(p, clone_flags);

+#ifdef CONFIG_PROC_STACK
+ p->stack_start = (stack_start == KSTK_ESP(current)) ?
+ current->stack_start : stack_start;
+#endif
+
/* Perform scheduler related setup. Assign this task to a CPU. */
sched_fork(p, clone_flags);