coredump: format_corename: fix the "core_uses_pid" logic

I don't understand why the multi-thread coredump implies the core_uses_pid
behaviour, but we shouldn't use mm->mm_users for that.  This counter can
be incremented by get_task_mm().  Use the valued returned by
coredump_wait() instead.

Also, remove the "const char *pattern" argument, format_corename() can use
core_pattern directly.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Oleg Nesterov 2008-07-25 01:47:47 -07:00 committed by Linus Torvalds
parent a94e2d408e
commit 565b9b14e7

View File

@ -1379,17 +1379,14 @@ EXPORT_SYMBOL(set_binfmt);
* name into corename, which must have space for at least
* CORENAME_MAX_SIZE bytes plus one byte for the zero terminator.
*/
static int format_corename(char *corename, const char *pattern, long signr)
static int format_corename(char *corename, int nr_threads, long signr)
{
const char *pat_ptr = pattern;
const char *pat_ptr = core_pattern;
int ispipe = (*pat_ptr == '|');
char *out_ptr = corename;
char *const out_end = corename + CORENAME_MAX_SIZE;
int rc;
int pid_in_pattern = 0;
int ispipe = 0;
if (*pattern == '|')
ispipe = 1;
/* Repeat as long as we have more pattern to process and more output
space */
@ -1490,7 +1487,7 @@ static int format_corename(char *corename, const char *pattern, long signr)
* and core_uses_pid is set, then .%pid will be appended to
* the filename. Do not do this for piped commands. */
if (!ispipe && !pid_in_pattern
&& (core_uses_pid || atomic_read(&current->mm->mm_users) != 1)) {
&& (core_uses_pid || nr_threads)) {
rc = snprintf(out_ptr, out_end - out_ptr,
".%d", task_tgid_vnr(current));
if (rc > out_end - out_ptr)
@ -1753,7 +1750,7 @@ int do_coredump(long signr, int exit_code, struct pt_regs * regs)
* uses lock_kernel()
*/
lock_kernel();
ispipe = format_corename(corename, core_pattern, signr);
ispipe = format_corename(corename, retval, signr);
unlock_kernel();
/*
* Don't bother to check the RLIMIT_CORE value if core_pattern points