1. 22 Jun, 2017 2 commits
  2. 20 Jun, 2017 16 commits
    • Davidlohr Bueso's avatar
      sched/core: Drop the unused try_get_task_struct() helper function · f11cc076
      Davidlohr Bueso authored
      This function was introduced by:
      
        150593bf ("sched/api: Introduce task_rcu_dereference() and try_get_task_struct()")
      
      ... to allow easier usage of task_rcu_dereference(), however no users
      were ever added. Drop the helper.
      Signed-off-by: default avatarDavidlohr Bueso <dbueso@suse.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: dave@stgolabs.net
      Link: http://lkml.kernel.org/r/20170615023730.22827-1-dave@stgolabs.netSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      f11cc076
    • Ingo Molnar's avatar
      Merge branch 'WIP.sched/core' into sched/core · 902b3194
      Ingo Molnar authored
       Conflicts:
      	kernel/sched/Makefile
      
      Pick up the waitqueue related renames - it didn't get much feedback,
      so it appears to be uncontroversial. Famous last words? ;-)
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      902b3194
    • Daniel Axtens's avatar
      sched/fair: WARN() and refuse to set buddy when !se->on_rq · c5ae366e
      Daniel Axtens authored
      If we set a next or last buddy for a se that is not on_rq, we will
      end up taking a NULL pointer dereference in wakeup_preempt_entity
      via pick_next_task_fair.
      
      Detect when we would be about to do that, throw a warning and
      then refuse to actually set it.
      
      This has been suggested at least twice:
      
        https://marc.info/?l=linux-kernel&m=146651668921468&w=2
        https://lkml.org/lkml/2016/6/16/663
      
      I recently had to debug a problem with these (we hadn't backported
      Konstantin's patches in this area) and this would have saved a lot
      of time/pain.
      
      Just do it.
      Signed-off-by: default avatarDaniel Axtens <dja@axtens.net>
      Cc: Ben Segall <bsegall@google.com>
      Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/20170510201139.16236-1-dja@axtens.netSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      c5ae366e
    • Ingo Molnar's avatar
      sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well · 6d3aed3d
      Ingo Molnar authored
      This definition of SCHED_WARN_ON():
      
       #define SCHED_WARN_ON(x)        ((void)(x))
      
      is not fully compatible with the 'real' WARN_ON_ONCE() primitive, as it
      has no return value, so it cannot be used in conditionals.
      
      Fix it.
      
      Cc: Daniel Axtens <dja@axtens.net>
      Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6d3aed3d
    • Ingo Molnar's avatar
      sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming · 2055da97
      Ingo Molnar authored
      So I've noticed a number of instances where it was not obvious from the
      code whether ->task_list was for a wait-queue head or a wait-queue entry.
      
      Furthermore, there's a number of wait-queue users where the lists are
      not for 'tasks' but other entities (poll tables, etc.), in which case
      the 'task_list' name is actively confusing.
      
      To clear this all up, name the wait-queue head and entry list structure
      fields unambiguously:
      
      	struct wait_queue_head::task_list	=> ::head
      	struct wait_queue_entry::task_list	=> ::entry
      
      For example, this code:
      
      	rqw->wait.task_list.next != &wait->task_list
      
      ... is was pretty unclear (to me) what it's doing, while now it's written this way:
      
      	rqw->wait.head.next != &wait->entry
      
      ... which makes it pretty clear that we are iterating a list until we see the head.
      
      Other examples are:
      
      	list_for_each_entry_safe(pos, next, &x->task_list, task_list) {
      	list_for_each_entry(wq, &fence->wait.task_list, task_list) {
      
      ... where it's unclear (to me) what we are iterating, and during review it's
      hard to tell whether it's trying to walk a wait-queue entry (which would be
      a bug), while now it's written as:
      
      	list_for_each_entry_safe(pos, next, &x->head, entry) {
      	list_for_each_entry(wq, &fence->wait.head, entry) {
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      2055da97
    • Ingo Molnar's avatar
      sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c · 5822a454
      Ingo Molnar authored
      The key hashed waitqueue data structures and their initialization
      was done in the main scheduler file for no good reason, move them
      to sched/wait_bit.c instead.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      5822a454
    • Ingo Molnar's avatar
      sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h> · 5dd43ce2
      Ingo Molnar authored
      The wait_bit*() types and APIs are mixed into wait.h, but they
      are a pretty orthogonal extension of wait-queues.
      
      Furthermore, only about 50 kernel files use these APIs, while
      over 1000 use the regular wait-queue functionality.
      
      So clean up the main wait.h by moving the wait-bit functionality
      out of it, into a separate .h and .c file:
      
        include/linux/wait_bit.h  for types and APIs
        kernel/sched/wait_bit.c   for the implementation
      
      Update all header dependencies.
      
      This reduces the size of wait.h rather significantly, by about 30%.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      5dd43ce2
    • Ingo Molnar's avatar
      sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h> · 4b1c480b
      Ingo Molnar authored
      So there's over 300 CPP macro line-continuation backslashes in
      include/linux/wait.h (!!), which are aligned vertically to make
      the macro maze a bit more navigable.
      
      The recent renames and reorganization broke some of them, and
      instead of re-aligning them in every patch (which would add
      a lot of stylistic noise to the patches and make them less
      readable), I just ignored them - and fixed them up in a single
      go in this patch.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      4b1c480b
    • Ingo Molnar's avatar
      sched/wait: Improve the bit-wait API parameter names in the API function prototypes · 939798a0
      Ingo Molnar authored
      Contrary to kernel tradition, most of the bit-wait function prototypes
      in <linux/wait.h> don't fully define the parameter names, they only
      list the types:
      
      	int out_of_line_wait_on_bit_timeout(void *, int, wait_bit_action_f *, unsigned, unsigned long);
      
      ... which is pretty passive-aggressive in terms of informing the reader
      about what these functions are doing.
      
      Fill in the parameter names, such as:
      
      	int out_of_line_wait_on_bit_timeout(void *word, int, wait_bit_action_f *action, unsigned int mode, unsigned long timeout);
      
      Also turn spurious (and inconsistently utilized) cases of 'unsigned' into 'unsigned int'.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      939798a0
    • Ingo Molnar's avatar
      sched/wait: Standardize wait_bit_queue naming · 76c85ddc
      Ingo Molnar authored
      So wait-bit-queue head variables are often named:
      
      	struct wait_bit_queue *q
      
      ... which is a bit ambiguous and super confusing, because
      they clearly suggest wait-queue head semantics and behavior
      (they rhyme with the old wait_queue_t *q naming), while they
      are extended wait-queue _entries_, not heads!
      
      They are misnomers in two ways:
      
       - the 'wait_bit_queue' leaves open the question of whether
         it's an entry or a head
      
       - the 'q' parameter and local variable naming falsely implies
         that it's a 'queue' - while it's an entry.
      
      This resulted in sometimes confusing cases such as:
      
      	finish_wait(wq, &q->wait);
      
      where the 'q' is not a wait-queue head, but a wait-bit-queue entry.
      
      So improve this all by standardizing wait-bit-queue nomenclature
      similar to wait-queue head naming:
      
      	struct wait_bit_queue   => struct wait_bit_queue_entry
      	q			=> wbq_entry
      
      Which makes it all a much clearer:
      
      	struct wait_bit_queue_entry *wbq_entry
      
      ... and turns the former confusing piece of code into:
      
      	finish_wait(wq_head, &wbq_entry->wq_entry;
      
      which IMHO makes it apparently clear what we are doing,
      without having to analyze the context of the code: we are
      adding a wait-queue entry to a regular wait-queue head,
      which entry is embedded in a wait-bit-queue entry.
      
      I'm not a big fan of acronyms, but repeating wait_bit_queue_entry
      in field and local variable names is too long, so Hopefully it's
      clear enough that 'wq_' prefixes stand for wait-queues, while
      'wbq_' prefixes stand for wait-bit-queues.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      76c85ddc
    • Ingo Molnar's avatar
      sched/wait: Standardize 'struct wait_bit_queue' wait-queue entry field name · 21417136
      Ingo Molnar authored
      Rename 'struct wait_bit_queue::wait' to ::wq_entry, to more clearly
      name it as a wait-queue entry.
      
      Propagate it to a couple of usage sites where the wait-bit-queue internals
      are exposed.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      21417136
    • Ingo Molnar's avatar
      sched/wait: Standardize internal naming of wait-queue heads · 9d9d676f
      Ingo Molnar authored
      The wait-queue head parameters and variables are named in a
      couple of ways, we have the following variants currently:
      
      	wait_queue_head_t *q
      	wait_queue_head_t *wq
      	wait_queue_head_t *head
      
      In particular the 'wq' naming is ambiguous in the sense whether it's
      a wait-queue head or entry name - as entries were often named 'wait'.
      
      ( Not to mention the confusion of any readers coming over from
        workqueue-land. )
      
      Standardize all this around a single, unambiguous parameter and
      variable name:
      
      	struct wait_queue_head *wq_head
      
      which is easy to grep for and also rhymes nicely with the wait-queue
      entry naming:
      
      	struct wait_queue_entry *wq_entry
      
      Also rename:
      
      	struct __wait_queue_head => struct wait_queue_head
      
      ... and use this struct type to migrate from typedefs usage to 'struct'
      usage, which is more in line with existing kernel practices.
      
      Don't touch any external users and preserve the main wait_queue_head_t
      typedef.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9d9d676f
    • Ingo Molnar's avatar
      sched/wait: Standardize internal naming of wait-queue entries · 50816c48
      Ingo Molnar authored
      So the various wait-queue entry variables in include/linux/wait.h
      and kernel/sched/wait.c are named in a colorfully inconsistent
      way:
      
      	wait_queue_entry_t *wait
      	wait_queue_entry_t *__wait	(even in plain C code!)
      	wait_queue_entry_t *q		(!)
      	wait_queue_entry_t *new		(making anyone who knows C++ cringe)
      	wait_queue_entry_t *old
      
      I think part of the reason for the inconsistency is the constant
      apparent confusion about what a wait queue 'head' versus 'entry' is.
      
      ( Some of the documentation talks about a 'wait descriptor', which is
        the wait-queue entry itself - further adding to the confusion. )
      
      The most common name is 'wait', but that in itself is somewhat
      ambiguous as well, as it does not really make it clear whether
      it's a wait-queue entry or head.
      
      To improve all this name the wait-queue entry structure parameters
      and variables consistently and push through this naming into all
      the wait.h and wait.c code:
      
      	struct wait_queue_entry *wq_entry
      
      The 'wq_' prefix makes it easy to grep for, and we also use the
      opportunity to move away from the typedef to a plain 'struct' naming:
      in the kernel we typically reserve typedefs for cases where a
      C structure is really small and somewhat opaque - such as pte_t.
      
      wait-queue entries are neither small nor opaque, so use the more
      standard 'struct xxx_entry' list management code nomenclature instead.
      
      ( We don't touch external users, and we preserve the typedef as well
        for actual wait-queue users, to reduce unnecessary churn. )
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      50816c48
    • Ingo Molnar's avatar
      sched/wait: Rename wait_queue_t => wait_queue_entry_t · ac6424b9
      Ingo Molnar authored
      Rename:
      
      	wait_queue_t		=>	wait_queue_entry_t
      
      'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
      but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
      which had to carry the name.
      
      Start sorting this out by renaming it to 'wait_queue_entry_t'.
      
      This also allows the real structure name 'struct __wait_queue' to
      lose its double underscore and become 'struct wait_queue_entry',
      which is the more canonical nomenclature for such data types.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      ac6424b9
    • Linus Torvalds's avatar
      Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux · 9705596d
      Linus Torvalds authored
      Pull clk fixes from Stephen Boyd:
       "One build fix for an Amlogic clk driver and a handful of Allwinner clk
        driver fixes for some DT bindings and a randconfig build error that
        all came in this merge window"
      
      * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
        clk: sunxi-ng: a64: Export PLL_PERIPH0 clock for the PRCM
        clk: sunxi-ng: h3: Export PLL_PERIPH0 clock for the PRCM
        dt-bindings: clock: sunxi-ccu: Add pll-periph to PRCM's needed clocks
        clk: sunxi-ng: sun5i: Fix ahb_bist_clk definition
        clk: sunxi-ng: enable SUNXI_CCU_MP for PRCM
        clk: meson: gxbb: fix build error without RESET_CONTROLLER
        clk: sunxi-ng: v3s: Fix usb otg device reset bit
        clk: sunxi-ng: a31: Correct lcd1-ch1 clock register offset
      9705596d
    • Linus Torvalds's avatar
      Merge tag 'ntb-4.12-bugfixes' of git://github.com/jonmason/ntb · 865be780
      Linus Torvalds authored
      Pull NTB fixes from Jon Mason:
       "NTB bug fixes to address the modinfo in ntb_perf, a couple of bugs in
        the NTB transport QP calculations, skx doorbells, and sleeping in
        ntb_async_tx_submit"
      
      * tag 'ntb-4.12-bugfixes' of git://github.com/jonmason/ntb:
        ntb: no sleep in ntb_async_tx_submit
        ntb: ntb_hw_intel: Skylake doorbells should be 32bits, not 64bits
        ntb_transport: fix bug calculating num_qps_mw
        ntb_transport: fix qp count bug
        NTB: ntb_test: fix bug printing ntb_perf results
        ntb: Correct modinfo usage statement for ntb_perf
      865be780
  3. 19 Jun, 2017 14 commits
  4. 18 Jun, 2017 7 commits
  5. 17 Jun, 2017 1 commit