linux/kernel/taskstats.c, branch v2.6.19

[PATCH] taskstats: fix sub-threads accounting

2006-10-31T16:07:00Z

If there are no listeners, taskstats_exit_send() just returns because taskstats_exit_alloc() didn't allocate *tidstats. This is wrong, each sub-thread should do fill_tgid_exit() on exit, otherwise its ->delays is not recorded in ->signal->stats and lost. Q: We don't send TASKSTATS_TYPE_AGGR_TGID when single-threaded process exits. Is it good? How can the listener figure out that it was actually a process exit, not sub-thread? Signed-off-by: Oleg Nesterov Cc: Balbir Singh Acked-by: Shailabh Nagar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] taskstats: fix sk_buff size calculation

2006-10-29T20:07:37Z

prepare_reply() adds GENL_HDRLEN to the payload (genlmsg_total_size()), but then it does genlmsg_put()->nlmsg_put(). This means we forget to reserve a room for 'struct nlmsghdr'. Signed-off-by: Oleg Nesterov Cc: Thomas Graf Cc: Andrew Morton Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Signed-off-by: Linus Torvalds

[PATCH] taskstats: fix sk_buff leak

2006-10-29T20:07:37Z

'return genlmsg_cancel()' in taskstats_user_cmd/taskstats_exit_send potentially leaks a skb. Unless we pass 'rep_skb' to the netlink layer we own sk_buff. This means we should always do kfree_skb() on failure. [ Thomas acked and pointed out missing return value in original version ] Signed-off-by: Oleg Nesterov Acked-by: Thomas Graf Cc: Andrew Morton Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Signed-off-by: Linus Torvalds

[PATCH] fill_tgid: cleanup delays accounting

2006-10-28T18:30:55Z

fill_tgid() should skip not only an already exited group leader. If the task has ->exit_state != 0 it already did exit_notify(), so it also did fill_tgid_exit()->delayacct_add_tsk(->signal->stats) and we should skip it to avoid a double accounting. This patch doesn't close the race completely, but it cleanups the code. Signed-off-by: Oleg Nesterov Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] taskstats: don't use tasklist_lock

2006-10-28T18:30:54Z

Remove tasklist_lock from taskstats.c. find_task_by_pid() is rcu-safe. ->siglock allows us to traverse subthread without tasklist. Q: delay accounting looks wrong to me. If sub-thread has already called taskstats_exit_send() but didn't call release_task(self) yet it will be accounted twice. The window is big. No? Signed-off-by: Oleg Nesterov Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] taskstats: kill ->taskstats_lock in favor of ->siglock

2006-10-28T18:30:54Z

signal_struct is (mostly) protected by ->sighand->siglock, I think we don't need ->taskstats_lock to protect ->stats. This also allows us to simplify the locking in fill_tgid(). Signed-off-by: Oleg Nesterov Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] fill_tgid: fix task_struct leak and possible oops

2006-10-28T18:30:54Z

1. fill_tgid() forgets to do put_task_struct(first). 2. release_task(first) can happen after fill_tgid() drops tasklist_lock, it is unsafe to dereference first->signal. This is a temporary fix, imho the locking should be reworked. Signed-off-by: Oleg Nesterov Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] csa: Extended system accounting over taskstats

2006-10-01T07:39:29Z

Add extended system accounting handling over taskstats interface. A CONFIG_TASK_XACCT flag is created to enable the extended accounting code. Signed-off-by: Jay Lan Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jes Sorensen Cc: Chris Sturtivant Cc: Tony Ernst Cc: Guillaume Thouvenin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] csa: basic accounting over taskstats

2006-10-01T07:39:29Z

Add some basic accounting fields to the taskstats struct, add a new kernel/tsacct.c to handle basic accounting data handling upon exit. A handle is added to taskstats.c to invoke the basic accounting data handling. Signed-off-by: Jay Lan Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jes Sorensen Cc: Chris Sturtivant Cc: Tony Ernst Cc: Guillaume Thouvenin Cc: "Michal Piotrowski" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Fix taskstats size calculation (use the new genetlink utility functions)

2006-10-01T07:39:29Z

The addition of the CSA patch pushed the size of struct taskstats to 256 bytes. This exposed a problem with prepare_reply(), we were not allocating space for the netlink and genetlink header. It worked earlier because alloc_skb() would align the skb to SMP_CACHE_BYTES, which added some additonal bytes. Signed-off-by: Balbir Singh Cc: Jamal Hadi Cc: Shailabh Nagar Cc: Thomas Graf Cc: "David S. Miller" Cc: Jay Lan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds