[PATCH iproute2-next 0/7] ss: Introduce -T, --threads option

[Peilin Ye <yepeilin.cs@gmail.com>]

From: Peilin Ye <peilin.ye@bytedance.com>

Hi all,

This patchset adds a new ss option, -T (--threads), to show thread
information.  It extends the -p (--processes) option, and should be useful
for debugging, monitoring multi-threaded applications.  Example output:

  $ ss -ltT "sport = 1234"
  State   Recv-Q  Send-Q  Local Address:Port      Peer Address:Port       Process
  LISTEN  0       100           0.0.0.0:1234           0.0.0.0:*           users:(("test",pid=2932547,tid=2932548,fd=3),("test",pid=2932547,tid=2932547,fd=3))

It implies -p i.e. it outputs all threads in the thread group, including
the thread group leader.  When -T is used, -Z and -z also show SELinux
contexts for threads.

[1-5/7] are small clean-ups for the user_ent_hash_build() function.  [6/7]
factors out logic iterating $PROC_ROOT/$PID/fd/ from user_ent_hash_build()
to make [7/7] easier.  [7/7] actually implements the feature.

Thanks,
Peilin Ye (7):
  ss: Use assignment-suppression character in sscanf()
  ss: Remove unnecessary stack variable 'p' in user_ent_hash_build()
  ss: Do not call user_ent_hash_build() more than once
  ss: Delete unnecessary call to snprintf() in user_ent_hash_build()
  ss: Fix coding style issues in user_ent_hash_build()
  ss: Factor out fd iterating logic from user_ent_hash_build()
  ss: Introduce -T, --threads option

 man/man8/ss.8 |   8 +-
 misc/ss.c     | 230 +++++++++++++++++++++++++++++---------------------
 2 files changed, 142 insertions(+), 96 deletions(-)

-- 
2.20.1