coredump: factor out the setting of PF_DUMPCORE

Cleanup.  Every linux_binfmt->core_dump() sets PF_DUMPCORE, move this into
zap_threads() called by do_coredump().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Neil Horman <nhorman@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/ia32/ia32_aout.c

@@ -162,7 +162,6 @@ static int aout_core_dump(long signr, struct pt_regs *regs, struct file *file,
 	fs = get_fs();
 	set_fs(KERNEL_DS);
 	has_dumped = 1;
-	current->flags |= PF_DUMPCORE;
 	strncpy(dump.u_comm, current->comm, sizeof(current->comm));
 	dump.u_ar0 = offsetof(struct user32, regs);
 	dump.signal = signr;

fs/binfmt_aout.c

@@ -62,7 +62,6 @@ static int aout_core_dump(struct coredump_params *cprm)
 	fs = get_fs();
 	set_fs(KERNEL_DS);
 	has_dumped = 1;
-	current->flags |= PF_DUMPCORE;
        	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
 	dump.u_ar0 = offsetof(struct user, regs);
 	dump.signal = cprm->siginfo->si_signo;

fs/binfmt_elf.c

@@ -2092,8 +2092,7 @@ static int elf_core_dump(struct coredump_params *cprm)
 		goto cleanup;
 
 	has_dumped = 1;
-	current->flags |= PF_DUMPCORE;
-  
+
 	fs = get_fs();
 	set_fs(KERNEL_DS);
 

fs/binfmt_elf_fdpic.c

@@ -1687,8 +1687,6 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 	fill_elf_fdpic_header(elf, e_phnum);
 
 	has_dumped = 1;
-	current->flags |= PF_DUMPCORE;
-
 	/*
 	 * Set up the notes in similar form to SVR4 core dumps made
 	 * with info from their /proc.

fs/coredump.c

@@ -299,6 +299,7 @@ static int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
 	if (unlikely(nr < 0))
 		return nr;
 
+	tsk->flags = PF_DUMPCORE;
 	if (atomic_read(&mm->mm_users) == nr + 1)
 		goto done;
 	/*