[resend][PATCH v10 1/2] /proc/PID/status: show all sets of pid according to ns

[resend][PATCH v10 1/2] /proc/PID/status: show all sets of pid according to ns

[Chen Hanxiao]

If some issues occurred inside a container guest, host user
could not know which process is in trouble just by guest pid:
the users of container guest only knew the pid inside containers.
This will bring obstacle for trouble shooting.

This patch adds four fields: NStgid, NSpid, NSpgid and NSsid:
a) In init_pid_ns, nothing changed;

b) In one pidns, will tell the pid inside containers:
  NStgid: 21776   5       1
  NSpid:  21776   5       1
  NSpgid: 21776   5       1
  NSsid:  21729   1       0
  ** Process id is 21776 in level 0, 5 in level 1, 1 in level 2.

c) If pidns is nested, it depends on which pidns are you in.
  NStgid: 5       1
  NSpid:  5       1
  NSpgid: 5       1
  NSsid:  1       0
  ** Views from level 1

Acked-by: Serge Hallyn <serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
Acked-by: "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>

Tested-by: Serge Hallyn <serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
Tested-by: Nathan Scott <nathans-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

Signed-off-by: Chen Hanxiao <chenhanxiao-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
---
v10: remove trailing space of pid numbers
     rebased on 3.19
v9: rebased on 3.19-rc1
No change from v4-v8
v3: add another two fielsd: NSpgid and NSsid.
v2: add two new fields: NStgid and NSpid.
    keep fields of Tgid and Pid unchanged for back compatibility.

 fs/proc/array.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 1295a00..d79bad9 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -188,6 +188,22 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
 			   from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
 	put_cred(cred);
 
+	seq_puts(m, "\nNStgid:");
+	for (g = ns->level; g <= pid->level; g++)
+		seq_printf(m, "\t%d",
+			task_tgid_nr_ns(p, pid->numbers[g].ns));
+	seq_puts(m, "\nNSpid:");
+	for (g = ns->level; g <= pid->level; g++)
+		seq_printf(m, "\t%d",
+			task_pid_nr_ns(p, pid->numbers[g].ns));
+	seq_puts(m, "\nNSpgid:");
+	for (g = ns->level; g <= pid->level; g++)
+		seq_printf(m, "\t%d",
+			task_pgrp_nr_ns(p, pid->numbers[g].ns));
+	seq_puts(m, "\nNSsid:");
+	for (g = ns->level; g <= pid->level; g++)
+		seq_printf(m, "\t%d",
+			task_session_nr_ns(p, pid->numbers[g].ns));
 	seq_putc(m, '\n');
 }
 
-- 
2.1.0

Re: [resend][PATCH v10 1/2] /proc/PID/status: show all sets of pid according to ns

[Serge E. Hallyn]

On Sun, Feb 22, 2015 at 07:48:04PM +0800, Chen Hanxiao wrote:
> If some issues occurred inside a container guest, host user
> could not know which process is in trouble just by guest pid:
> the users of container guest only knew the pid inside containers.
> This will bring obstacle for trouble shooting.
> 
> This patch adds four fields: NStgid, NSpid, NSpgid and NSsid:
> a) In init_pid_ns, nothing changed;
> 
> b) In one pidns, will tell the pid inside containers:
>   NStgid: 21776   5       1
>   NSpid:  21776   5       1
>   NSpgid: 21776   5       1
>   NSsid:  21729   1       0
>   ** Process id is 21776 in level 0, 5 in level 1, 1 in level 2.
> 
> c) If pidns is nested, it depends on which pidns are you in.
>   NStgid: 5       1
>   NSpid:  5       1
>   NSpgid: 5       1
>   NSsid:  1       0
>   ** Views from level 1

So obviously (since I acked it) I see no problems with this patch or
the api, but it occurs to me that you have not cc:d linux-api?  Since
a procfile addition is something we're stuck with for eternity, it
seems worth it.  If we get an ack from there, then i'd say email
to Linus directly.  Putting this through -mm doesn't really seem
necessary given its nature.

> Acked-by: Serge Hallyn <serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
> Acked-by: "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
> 
> Tested-by: Serge Hallyn <serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
> Tested-by: Nathan Scott <nathans-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> 
> Signed-off-by: Chen Hanxiao <chenhanxiao-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
> ---
> v10: remove trailing space of pid numbers
>      rebased on 3.19
> v9: rebased on 3.19-rc1
> No change from v4-v8
> v3: add another two fielsd: NSpgid and NSsid.
> v2: add two new fields: NStgid and NSpid.
>     keep fields of Tgid and Pid unchanged for back compatibility.
> 
>  fs/proc/array.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/fs/proc/array.c b/fs/proc/array.c
> index 1295a00..d79bad9 100644
> --- a/fs/proc/array.c
> +++ b/fs/proc/array.c
> @@ -188,6 +188,22 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
>  			   from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
>  	put_cred(cred);
>  
> +	seq_puts(m, "\nNStgid:");
> +	for (g = ns->level; g <= pid->level; g++)
> +		seq_printf(m, "\t%d",
> +			task_tgid_nr_ns(p, pid->numbers[g].ns));
> +	seq_puts(m, "\nNSpid:");
> +	for (g = ns->level; g <= pid->level; g++)
> +		seq_printf(m, "\t%d",
> +			task_pid_nr_ns(p, pid->numbers[g].ns));
> +	seq_puts(m, "\nNSpgid:");
> +	for (g = ns->level; g <= pid->level; g++)
> +		seq_printf(m, "\t%d",
> +			task_pgrp_nr_ns(p, pid->numbers[g].ns));
> +	seq_puts(m, "\nNSsid:");
> +	for (g = ns->level; g <= pid->level; g++)
> +		seq_printf(m, "\t%d",
> +			task_session_nr_ns(p, pid->numbers[g].ns));
>  	seq_putc(m, '\n');
>  }
>  
> -- 
> 2.1.0
> 
> _______________________________________________
> Containers mailing list
> Containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
> https://lists.linuxfoundation.org/mailman/listinfo/containers

[PATCH v10 2/2] docs: add missing and new /proc/PID/status file entries, fix typos

[Chen Hanxiao]

From: Nathan Scott <nathans-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

---
 Documentation/filesystems/proc.txt | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index a07ba61..6d37062 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -200,12 +200,12 @@ contains details information about the process itself.  Its fields are
 explained in Table 1-4.
 
 (for SMP CONFIG users)
-For making accounting scalable, RSS related information are handled in
-asynchronous manner and the vaule may not be very precise. To see a precise
+For making accounting scalable, RSS related information are handled in an
+asynchronous manner and the value may not be very precise. To see a precise
 snapshot of a moment, you can see /proc/<pid>/smaps file and scan page table.
 It's slow but very precise.
 
-Table 1-2: Contents of the status files (as of 2.6.30-rc7)
+Table 1-2: Contents of the status files (as of 3.20.0)
 ..............................................................................
  Field                       Content
  Name                        filename of the executable
@@ -213,6 +213,7 @@ Table 1-2: Contents of the status files (as of 2.6.30-rc7)
                              in an uninterruptible wait, Z is zombie,
 			     T is traced or stopped)
  Tgid                        thread group ID
+ Ngid                        NUMA group ID (0 if none)
  Pid                         process id
  PPid                        process id of the parent process
  TracerPid                   PID of process tracing this process (0 if not)
@@ -220,6 +221,10 @@ Table 1-2: Contents of the status files (as of 2.6.30-rc7)
  Gid                         Real, effective, saved set, and  file system GIDs
  FDSize                      number of file descriptor slots currently allocated
  Groups                      supplementary group list
+ NStgid                      descendant namespace thread group ID hierarchy
+ NSpid                       descendant namespace process ID hierarchy
+ NSpgid                      descendant namespace process group ID hierarchy
+ NSsid                       descendant namespace session ID hierarchy
  VmPeak                      peak virtual memory size
  VmSize                      total program size
  VmLck                       locked memory size
-- 
2.1.0