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  1. 29 3月, 2006 12 次提交
  3. 28 3月, 2006 2 次提交
  5. 23 3月, 2006 1 次提交
  7. 19 3月, 2006 1 次提交
  9. 21 2月, 2006 1 次提交
  11. 15 1月, 2006 2 次提交
  13. 12 1月, 2006 1 次提交
  15. 11 1月, 2006 2 次提交
  17. 10 1月, 2006 1 次提交
  19. 09 1月, 2006 3 次提交
  21. 14 11月, 2005 1 次提交
  23. 07 11月, 2005 1 次提交
  25. 31 10月, 2005 3 次提交
  27. 30 10月, 2005 1 次提交
    • H
      [PATCH] mm: update_hiwaters just in time · 365e9c87
      由 Hugh Dickins 提交于 
      update_mem_hiwater has attracted various criticisms, in particular from those
concerned with mm scalability.  Originally it was called whenever rss or
total_vm got raised.  Then many of those callsites were replaced by a timer
tick call from account_system_time.  Now Frank van Maarseveen reports that to
be found inadequate.  How about this?  Works for Frank.

Replace update_mem_hiwater, a poor combination of two unrelated ops, by macros
update_hiwater_rss and update_hiwater_vm.  Don't attempt to keep
mm->hiwater_rss up to date at timer tick, nor every time we raise rss (usually
by 1): those are hot paths.  Do the opposite, update only when about to lower
rss (usually by many), or just before final accounting in do_exit.  Handle
mm->hiwater_vm in the same way, though it's much less of an issue.  Demand
that whoever collects these hiwater statistics do the work of taking the
maximum with rss or total_vm.

And there has been no collector of these hiwater statistics in the tree.  The
new convention needs an example, so match Frank's usage by adding a VmPeak
line above VmSize to /proc/<pid>/status, and also a VmHWM line above VmRSS
(High-Water-Mark or High-Water-Memory).

There was a particular anomaly during mremap move, that hiwater_vm might be
captured too high.  A fleeting such anomaly remains, but it's quickly
corrected now, whereas before it would stick.

What locking?  None: if the app is racy then these statistics will be racy,
it's not worth any overhead to make them exact.  But whenever it suits,
hiwater_vm is updated under exclusive mmap_sem, and hiwater_rss under
page_table_lock (for now) or with preemption disabled (later on): without
going to any trouble, minimize the time between reading current values and
updating, to minimize those occasions when a racing thread bumps a count up
and back down in between.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      365e9c87
  29. 28 10月, 2005 1 次提交
  31. 24 10月, 2005 1 次提交
    • O
      [PATCH] posix-timers: remove false BUG_ON() from run_posix_cpu_timers() · 3de463c7
      由 Oleg Nesterov 提交于 
      do_exit() clears ->it_##clock##_expires, but nothing prevents
another cpu to attach the timer to exiting process after that.

After exit_notify() does 'write_unlock_irq(&tasklist_lock)' and
before do_exit() calls 'schedule() local timer interrupt can find
tsk->exit_state != 0. If that state was EXIT_DEAD (or another cpu
does sys_wait4) interrupted task has ->signal == NULL.

At this moment exiting task has no pending cpu timers, they were cleaned
up in __exit_signal()->posix_cpu_timers_exit{,_group}(), so we can just
return from irq.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      3de463c7
  33. 22 10月, 2005 1 次提交
    • R
      [PATCH] Call exit_itimers from do_exit, not __exit_signal · 25f407f0
      由 Roland McGrath 提交于 
      When I originally moved exit_itimers into __exit_signal, that was the only
place where we could reliably know it was the last thread in the group
dying, without races.  Since then we've gotten the signal_struct.live
counter, and do_exit can reliably do group-wide cleanup work.

This patch moves the call to do_exit, where it's made without locks.  This
avoids the deadlock issues that the old __exit_signal code's comment talks
about, and the one that Oleg found recently with process CPU timers.

[ This replaces e03d13e9, which is why
  it was just reverted. ]
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      25f407f0
  35. 02 10月, 2005 1 次提交
    • L
      Fix inequality comparison against "task->state" · 14bf01bb
      由 Linus Torvalds 提交于 
      We should always use bitmask ops, rather than depend on some ordering of
the different states.  With the TASK_NONINTERACTIVE flag, the inequality
doesn't really work.

Oleg Nesterov argues (likely correctly) that this test is unnecessary in
the first place.  However, the minimal fix for now is to at least make
it work in the presense of TASK_NONINTERACTIVE.  Waiting for consensus
from Roland & co on potential bigger cleanups.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      14bf01bb
  37. 18 9月, 2005 1 次提交
  39. 10 9月, 2005 2 次提交
    • D
      [PATCH] files: files struct with RCU · ab2af1f5
      由 Dipankar Sarma 提交于 
      Patch to eliminate struct files_struct.file_lock spinlock on the reader side
and use rcu refcounting rcuref_xxx api for the f_count refcounter.  The
updates to the fdtable are done by allocating a new fdtable structure and
setting files->fdt to point to the new structure.  The fdtable structure is
protected by RCU thereby allowing lock-free lookup.  For fd arrays/sets that
are vmalloced, we use keventd to free them since RCU callbacks can't sleep.  A
global list of fdtable to be freed is not scalable, so we use a per-cpu list.
If keventd is already handling the current cpu's work, we use a timer to defer
queueing of that work.

Since the last publication, this patch has been re-written to avoid using
explicit memory barriers and use rcu_assign_pointer(), rcu_dereference()
premitives instead.  This required that the fd information is kept in a
separate structure (fdtable) and updated atomically.
Signed-off-by: NDipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ab2af1f5
    • D
      [PATCH] files: break up files struct · badf1662
      由 Dipankar Sarma 提交于 
      In order for the RCU to work, the file table array, sets and their sizes must
be updated atomically.  Instead of ensuring this through too many memory
barriers, we put the arrays and their sizes in a separate structure.  This
patch takes the first step of putting the file table elements in a separate
structure fdtable that is embedded withing files_struct.  It also changes all
the users to refer to the file table using files_fdtable() macro.  Subsequent
applciation of RCU becomes easier after this.
Signed-off-by: NDipankar Sarma <dipankar@in.ibm.com>
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      badf1662
  41. 05 8月, 2005 1 次提交