[PATCH] gdb: filter inferiors using linux_target in check_zombie_leaders

[PATCH] gdb: filter inferiors using linux_target in check_zombie_leaders

[Simon Marchi]

check_zombie_leaders, a help function of the linux-nat target, iterates
on all inferiors when looking for zombie leaders.  This potentially
includes inferiors from other targets.  This is not harmful, for
inferiors from other targets it will simply not find a matching lwp.
But it would make sense to only iterate on the target's inferiors.

We can also remove the "inf->pid == 0" check: inferiors that have the
linux-nat target pushed will have execution and a non-zero pid.

Change-Id: Ie31465dbae983fcc639478939877e1616848738b
---
 gdb/linux-nat.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index 5b747f7822b3..352716eda9ba 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -3052,14 +3052,9 @@ linux_nat_filter_event (int lwpid, int status)
 static void
 check_zombie_leaders (void)
 {
-  for (inferior *inf : all_inferiors ())
+  for (inferior *inf : all_inferiors (linux_target))
     {
-      struct lwp_info *leader_lp;
-
-      if (inf->pid == 0)
-	continue;
-
-      leader_lp = find_lwp_pid (ptid_t (inf->pid));
+      lwp_info *leader_lp = find_lwp_pid (ptid_t (inf->pid));
       if (leader_lp != NULL
 	  /* Check if there are other threads in the group, as we may
 	     have raced with the inferior simply exiting.  */

base-commit: f6b3ad544063314a1e7fcaa703b5e29f5ff10780
-- 
2.35.1

Re: [PATCH] gdb: filter inferiors using linux_target in check_zombie_leaders

[Andrew Burgess]

* Simon Marchi via Gdb-patches <gdb-patches@sourceware.org> [2022-02-18 17:58:39 -0500]:

> check_zombie_leaders, a help function of the linux-nat target, iterates
> on all inferiors when looking for zombie leaders.  This potentially
> includes inferiors from other targets.  This is not harmful, for
> inferiors from other targets it will simply not find a matching lwp.
> But it would make sense to only iterate on the target's inferiors.
> 
> We can also remove the "inf->pid == 0" check: inferiors that have the
> linux-nat target pushed will have execution and a non-zero pid.

LGTM.

Thanks,
Andrew

> 
> Change-Id: Ie31465dbae983fcc639478939877e1616848738b
> ---
>  gdb/linux-nat.c | 9 ++-------
>  1 file changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
> index 5b747f7822b3..352716eda9ba 100644
> --- a/gdb/linux-nat.c
> +++ b/gdb/linux-nat.c
> @@ -3052,14 +3052,9 @@ linux_nat_filter_event (int lwpid, int status)
>  static void
>  check_zombie_leaders (void)
>  {
> -  for (inferior *inf : all_inferiors ())
> +  for (inferior *inf : all_inferiors (linux_target))
>      {
> -      struct lwp_info *leader_lp;
> -
> -      if (inf->pid == 0)
> -	continue;
> -
> -      leader_lp = find_lwp_pid (ptid_t (inf->pid));
> +      lwp_info *leader_lp = find_lwp_pid (ptid_t (inf->pid));
>        if (leader_lp != NULL
>  	  /* Check if there are other threads in the group, as we may
>  	     have raced with the inferior simply exiting.  */
> 
> base-commit: f6b3ad544063314a1e7fcaa703b5e29f5ff10780
> -- 
> 2.35.1
>