BMC/Intel-BMC/linux.git/include/linux/sched.h, branch dev-4.7

Clarify naming of thread info/stack allocators

2016-06-24T22:09:37+00:00

We've had the thread info allocated together with the thread stack for most architectures for a long time (since the thread_info was split off from the task struct), but that is about to change. But the patches that move the thread info to be off-stack (and a part of the task struct instead) made it clear how confused the allocator and freeing functions are. Because the common case was that we share an allocation with the thread stack and the thread_info, the two pointers were identical. That identity then meant that we would have things like ti = alloc_thread_info_node(tsk, node); ... tsk->stack = ti; which certainly _worked_ (since stack and thread_info have the same value), but is rather confusing: why are we assigning a thread_info to the stack? And if we move the thread_info away, the "confusing" code just gets to be entirely bogus. So remove all this confusion, and make it clear that we are doing the stack allocation by renaming and clarifying the function names to be about the stack. The fact that the thread_info then shares the allocation is an implementation detail, and not really about the allocation itself. This is a pure renaming and type fix: we pass in the same pointer, it's just that we clarify what the pointer means. The ia64 code that actually only has one single allocation (for all of task_struct, thread_info and kernel thread stack) now looks a bit odd, but since "tsk->stack" is actually not even used there, that oddity doesn't matter. It would be a separate thing to clean that up, I intentionally left the ia64 changes as a pure brute-force renaming and type change. Acked-by: Andy Lutomirski Signed-off-by: Linus Torvalds

mm: oom_reaper: remove some bloat

2016-05-26T22:35:44+00:00

mmput_async is currently used only from the oom_reaper which is defined only for CONFIG_MMU. We can save work_struct in mm_struct for !CONFIG_MMU. [akpm@linux-foundation.org: fix typo, per Minchan] Link: http://lkml.kernel.org/r/20160520061658.GB19172@dhcp22.suse.cz Reported-by: Minchan Kim Signed-off-by: Michal Hocko Acked-by: Minchan Kim Cc: Tetsuo Handa Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-05-26T00:11:43+00:00

Pull scheduler fixes from Ingo Molnar: "Two fixes: one for a lost wakeup, the other to fix the compiler optimizing out preempt operations on ARM64 (and possibly other non-x86 architectures)" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/core: Fix remote wakeups sched/preempt: Fix preempt_count manipulations

sched/core: Fix remote wakeups

2016-05-25T06:35:18+00:00

Commit: b5179ac70de8 ("sched/fair: Prepare to fix fairness problems on migration") ... introduced a bug: Mike Galbraith found that it introduced a performance regression, while Paul E. McKenney reported lost wakeups and bisected it to this commit. The reason is that I mis-read ttwu_queue() such that I assumed any wakeup that got a remote queue must have had the task migrated. Since this is not so; we need to transfer this information between queueing the wakeup and actually doing the wakeup. Use a new task_struct::sched_flag for this, we already write to sched_contributes_to_load in the wakeup path so this is a hot and modified cacheline. Reported-by: Paul E. McKenney Reported-by: Mike Galbraith Tested-by: Mike Galbraith Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Hunter Cc: Andy Lutomirski Cc: Ben Segall Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Matt Fleming Cc: Morten Rasmussen Cc: Oleg Nesterov Cc: Paul Turner Cc: Pavan Kondeti Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Cc: byungchul.park@lge.com Fixes: b5179ac70de8 ("sched/fair: Prepare to fix fairness problems on migration") Link: http://lkml.kernel.org/r/20160523091907.GD15728@worktop.ger.corp.intel.com Signed-off-by: Ingo Molnar

signal: make oom_flags a bool

2016-05-24T00:04:14+00:00

Currently the size of "struct signal_struct"->oom_flags member is sizeof(unsigned) bytes, but only one flag OOM_FLAG_ORIGIN which is updated by current thread is defined. We can convert OOM_FLAG_ORIGIN into a bool, and reuse the saved bytes for updating from the OOM killer and/or the OOM reaper thread. By the way, do we care about a race window between run_store() and swapoff() because it would be theoretically possible that two threads sharing the "struct signal_struct" concurrently call respective functions? If we care, we can make oom_flags an atomic_t. Signed-off-by: Tetsuo Handa Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'akpm' (patches from Andrew)

2016-05-21T05:31:33+00:00

Merge more updates from Andrew Morton: - the rest of MM - KASAN updates - procfs updates - exit, fork updates - printk updates - lib/ updates - radix-tree testsuite updates - checkpatch updates - kprobes updates - a few other misc bits * emailed patches from Andrew Morton : (162 commits) samples/kprobes: print out the symbol name for the hooks samples/kprobes: add a new module parameter kprobes: add the "tls" argument for j_do_fork init/main.c: simplify initcall_blacklisted() fs/efs/super.c: fix return value checkpatch: improve --git shortcut checkpatch: reduce number of `git log` calls with --git checkpatch: add support to check already applied git commits checkpatch: add --list-types to show message types to show or ignore checkpatch: advertise the --fix and --fix-inplace options more checkpatch: whine about ACCESS_ONCE checkpatch: add test for keywords not starting on tabstops checkpatch: improve CONSTANT_COMPARISON test for structure members checkpatch: add PREFER_IS_ENABLED test lib/GCD.c: use binary GCD algorithm instead of Euclidean radix-tree: free up the bottom bit of exceptional entries for reuse dax: move RADIX_DAX_ definitions to dax.c radix-tree: make radix_tree_descend() more useful radix-tree: introduce radix_tree_replace_clear_tags() radix-tree: tidy up __radix_tree_create() ...

Merge tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

2016-05-21T05:20:48+00:00

Pull staging and IIO driver updates from Greg KH: "Here's the big staging and iio driver update for 4.7-rc1. I think we almost broke even with this release, only adding a few more lines than we removed, which isn't bad overall given that there's a bunch of new iio drivers added. The Lustre developers seem to have woken up from their sleep and have been doing a great job in cleaning up the code and pruning unused or old cruft, the filesystem is almost readable :) Other than that, just a lot of basic coding style cleanups in the churn. All have been in linux-next for a while with no reported issues" * tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (938 commits) Staging: emxx_udc: emxx_udc: fixed coding style issue staging/gdm724x: fix "alignment should match open parenthesis" issues staging/gdm724x: Fix avoid CamelCase staging: unisys: rename misleading var ii with frag staging: unisys: visorhba: switch success handling to error handling staging: unisys: visorhba: main path needs to flow down the left margin staging: unisys: visorinput: handle_locking_key() simplifications staging: unisys: visorhba: fail gracefully for thread creation failures staging: unisys: visornic: comment restructuring and removing bad diction staging: unisys: fix format string %Lx to %llx for u64 staging: unisys: remove unused struct members staging: unisys: visorchannel: correct variable misspelling staging: unisys: visorhba: replace functionlike macro with function staging: dgnc: Need to check for NULL of ch staging: dgnc: remove redundant condition check staging: dgnc: fix 'line over 80 characters' staging: dgnc: clean up the dgnc_get_modem_info() staging: lustre: lnet: enable configuration per NI interface staging: lustre: o2iblnd: properly set ibr_why staging: lustre: o2iblnd: remove last of kiblnd_tunables_fini ...

exit_thread: accept a task parameter to be exited

2016-05-21T00:58:30+00:00

We need to call exit_thread from copy_process in a fail path. So make it accept task_struct as a parameter. [v2] * s390: exit_thread_runtime_instr doesn't make sense to be called for non-current tasks. * arm: fix the comment in vfp_thread_copy * change 'me' to 'tsk' for task_struct * now we can change only archs that actually have exit_thread [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jiri Slaby Cc: "David S. Miller" Cc: "H. Peter Anvin" Cc: "James E.J. Bottomley" Cc: Aurelien Jacquiot Cc: Benjamin Herrenschmidt Cc: Catalin Marinas Cc: Chen Liqin Cc: Chris Metcalf Cc: Chris Zankel Cc: David Howells Cc: Fenghua Yu Cc: Geert Uytterhoeven Cc: Guan Xuetao Cc: Haavard Skinnemoen Cc: Hans-Christian Egtvedt Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: James Hogan Cc: Jeff Dike Cc: Jesper Nilsson Cc: Jiri Slaby Cc: Jonas Bonn Cc: Koichi Yasutake Cc: Lennox Wu Cc: Ley Foon Tan Cc: Mark Salter Cc: Martin Schwidefsky Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Mikael Starvik Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Ralf Baechle Cc: Rich Felker Cc: Richard Henderson Cc: Richard Kuo Cc: Richard Weinberger Cc: Russell King Cc: Steven Miao Cc: Thomas Gleixner Cc: Tony Luck Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

exit_thread: remove empty bodies

2016-05-21T00:58:30+00:00

Define HAVE_EXIT_THREAD for archs which want to do something in exit_thread. For others, let's define exit_thread as an empty inline. This is a cleanup before we change the prototype of exit_thread to accept a task parameter. [akpm@linux-foundation.org: fix mips] Signed-off-by: Jiri Slaby Cc: "David S. Miller" Cc: "H. Peter Anvin" Cc: "James E.J. Bottomley" Cc: Aurelien Jacquiot Cc: Benjamin Herrenschmidt Cc: Catalin Marinas Cc: Chen Liqin Cc: Chris Metcalf Cc: Chris Zankel Cc: David Howells Cc: Fenghua Yu Cc: Geert Uytterhoeven Cc: Guan Xuetao Cc: Haavard Skinnemoen Cc: Hans-Christian Egtvedt Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: James Hogan Cc: Jeff Dike Cc: Jesper Nilsson Cc: Jiri Slaby Cc: Jonas Bonn Cc: Koichi Yasutake Cc: Lennox Wu Cc: Ley Foon Tan Cc: Mark Salter Cc: Martin Schwidefsky Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Mikael Starvik Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Ralf Baechle Cc: Rich Felker Cc: Richard Henderson Cc: Richard Kuo Cc: Richard Weinberger Cc: Russell King Cc: Steven Miao Cc: Thomas Gleixner Cc: Tony Luck Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

userfaultfd: don't pin the user memory in userfaultfd_file_create()

2016-05-21T00:58:30+00:00

userfaultfd_file_create() increments mm->mm_users; this means that the memory won't be unmapped/freed if mm owner exits/execs, and UFFDIO_COPY after that can populate the orphaned mm more. Change userfaultfd_file_create() and userfaultfd_ctx_put() to use mm->mm_count to pin mm_struct. This means that atomic_inc_not_zero(mm->mm_users) is needed when we are going to actually play with this memory. Except handle_userfault() path doesn't need this, the caller must already have a reference. The patch adds the new trivial helper, mmget_not_zero(), it can have more users. Link: http://lkml.kernel.org/r/20160516172254.GA8595@redhat.com Signed-off-by: Oleg Nesterov Cc: Andrea Arcangeli Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds