From c107d1fdf90523b599c4f7782ac619db1c8717ba Mon Sep 17 00:00:00 2001
From: Ken Sato <ken.sato.ty@hitachi-solutions.com>
Date: Thu, 15 Mar 2018 14:29:16 +0900
Subject: [PATCH] fix: Bug for measuring rss in fork() refs: #1032

---
 kernel/include/cls.h            | 2 ++
 kernel/include/rusage_private.h | 7 ++++++-
 kernel/process.c                | 6 ++++--
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/kernel/include/cls.h b/kernel/include/cls.h
index 02de2bc7..d778407c 100644
--- a/kernel/include/cls.h
+++ b/kernel/include/cls.h
@@ -97,6 +97,8 @@ struct cpu_local_var {
 
 	ihk_spinlock_t smp_func_req_lock;
 	struct list_head smp_func_req_list;
+
+	struct process_vm *on_fork_vm;
 } __attribute__((aligned(64)));
 
 
diff --git a/kernel/include/rusage_private.h b/kernel/include/rusage_private.h
index dcc8f342..72401691 100644
--- a/kernel/include/rusage_private.h
+++ b/kernel/include/rusage_private.h
@@ -35,7 +35,7 @@ rusage_rss_add(unsigned long size)
 	unsigned long newval;
 	unsigned long oldval;
 	unsigned long retval;
-	struct process_vm *vm = cpu_local_var(current)->vm;
+	struct process_vm *vm;
 
 	newval = __sync_add_and_fetch(&rusage->rss_current, size);
 	oldval = rusage->memory_max_usage;
@@ -49,6 +49,11 @@ rusage_rss_add(unsigned long size)
 	}
 
 	/* process rss */
+	vm = cpu_local_var(on_fork_vm);
+	if (!vm) {
+		vm = cpu_local_var(current)->vm;
+	}
+
 	vm->currss += size;
 	if (vm->currss > vm->proc->maxrss) {
 		vm->proc->maxrss = vm->currss;
diff --git a/kernel/process.c b/kernel/process.c
index 5b817f3d..f574aa1c 100644
--- a/kernel/process.c
+++ b/kernel/process.c
@@ -398,6 +398,7 @@ clone_thread(struct thread *org, unsigned long pc, unsigned long sp,
 	int termsig = clone_flags & 0xff;
 	struct process *proc = NULL;
 	struct address_space *asp = NULL;
+	struct cpu_local_var *v = get_this_cpu_local_var();
 
 	if ((thread = ihk_mc_alloc_pages(KERNEL_STACK_NR_PAGES,
 					IHK_MC_AP_NOWAIT)) == NULL) {
@@ -484,12 +485,15 @@ clone_thread(struct thread *org, unsigned long pc, unsigned long sp,
 		dkprintf("fork(): copy_user_ranges()\n");
 		/* Copy user-space mappings.
 		 * TODO: do this with COW later? */
+		v->on_fork_vm = proc->vm;
 		if (copy_user_ranges(proc->vm, org->vm) != 0) {
 			release_address_space(asp);
+			v->on_fork_vm = NULL;
 			kfree(proc->vm);
 			kfree(proc);
 			goto err_free_proc;
 		}
+		v->on_fork_vm = NULL;
 
 		/* Copy mckfd list
 		   FIXME: Replace list manipulation with list_add() etc. */
@@ -522,8 +526,6 @@ clone_thread(struct thread *org, unsigned long pc, unsigned long sp,
 
 		thread->vm->vdso_addr = org->vm->vdso_addr;
 		thread->vm->vvar_addr = org->vm->vvar_addr;
-		thread->proc->maxrss = org->proc->maxrss;
-		thread->vm->currss = org->vm->currss;
 
 		thread->sigstack.ss_sp = org->sigstack.ss_sp;
 		thread->sigstack.ss_flags = org->sigstack.ss_flags;