user/sven/linux.git/include/linux/kernel.h, branch v4.9.46

min/max: remove sparse warnings when they're nested

2016-10-08T01:46:30Z

Currently, when min/max are nested within themselves, sparse will warn: warning: symbol '_min1' shadows an earlier one originally declared here warning: symbol '_min1' shadows an earlier one originally declared here warning: symbol '_min2' shadows an earlier one originally declared here This also immediately happens when min3() or max3() are used. Since sparse implements __COUNTER__, we can use __UNIQUE_ID() to generate unique variable names, avoiding this. Link: http://lkml.kernel.org/r/1471519773-29882-1-git-send-email-johannes@sipsolutions.net Signed-off-by: Johannes Berg Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sched/core: Optimize __schedule()

2016-09-22T12:53:45Z

Oleg noted that by making do_exit() use __schedule() for the TASK_DEAD context switch, we can avoid the TASK_DEAD special case currently in __schedule() because that avoids the extra preempt_disable() from schedule(). In order to facilitate this, create a do_task_dead() helper which we place in the scheduler code, such that it can access __schedule(). Also add some __noreturn annotations to the functions, there's no coming back from do_exit(). Suggested-by: Oleg Nesterov Signed-off-by: Peter Zijlstra (Intel) Cc: Cheng Chao Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: akpm@linux-foundation.org Cc: chris@chris-wilson.co.uk Cc: tj@kernel.org Link: http://lkml.kernel.org/r/20160913163729.GB5012@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar

dynamic_debug: only add header when used

2016-08-02T23:35:03Z

kernel.h header doesn't directly use dynamic debug, instead we can include it in module.c (which used it via kernel.h). printk.h only uses it if CONFIG_DYNAMIC_DEBUG is on, changing the inclusion to only happen in that case. Link: http://lkml.kernel.org/r/1468429793-16917-1-git-send-email-luisbg@osg.samsung.com [luisbg@osg.samsung.com: include dynamic_debug.h in drb_int.h] Link: http://lkml.kernel.org/r/1468447828-18558-2-git-send-email-luisbg@osg.samsung.com Signed-off-by: Luis de Bethencourt Cc: Rusty Russell Cc: Hidehiro Kawai Cc: Borislav Petkov Cc: Michal Nazarewicz Cc: Rasmus Villemoes Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

rcu: sysctl: Panic on RCU Stall

2016-06-15T23:00:05Z

It is not always easy to determine the cause of an RCU stall just by analysing the RCU stall messages, mainly when the problem is caused by the indirect starvation of rcu threads. For example, when preempt_rcu is not awakened due to the starvation of a timer softirq. We have been hard coding panic() in the RCU stall functions for some time while testing the kernel-rt. But this is not possible in some scenarios, like when supporting customers. This patch implements the sysctl kernel.panic_on_rcu_stall. If set to 1, the system will panic() when an RCU stall takes place, enabling the capture of a vmcore. The vmcore provides a way to analyze all kernel/tasks states, helping out to point to the culprit and the solution for the stall. The kernel.panic_on_rcu_stall sysctl is disabled by default. Changes from v1: - Fixed a typo in the git log - The if(sysctl_panic_on_rcu_stall) panic() is in a static function - Fixed the CONFIG_TINY_RCU compilation issue - The var sysctl_panic_on_rcu_stall is now __read_mostly Cc: Jonathan Corbet Cc: "Paul E. McKenney" Cc: Josh Triplett Cc: Steven Rostedt Cc: Mathieu Desnoyers Cc: Lai Jiangshan Acked-by: Christian Borntraeger Reviewed-by: Josh Triplett Reviewed-by: Arnaldo Carvalho de Melo Tested-by: "Luis Claudio R. Goncalves" Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Paul E. McKenney

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

2016-05-21T05:20:48Z

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 ...

include/linux: apply __malloc attribute

2016-05-20T02:12:14Z

Attach the malloc attribute to a few allocation functions. This helps gcc generate better code by telling it that the return value doesn't alias any existing pointers (which is even more valuable given the pessimizations implied by -fno-strict-aliasing). A simple example of what this allows gcc to do can be seen by looking at the last part of drm_atomic_helper_plane_reset: plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL); if (plane->state) { plane->state->plane = plane; plane->state->rotation = BIT(DRM_ROTATE_0); } which compiles to e8 99 bf d6 ff callq ffffffff8116d540 48 85 c0 test %rax,%rax 48 89 83 40 02 00 00 mov %rax,0x240(%rbx) 74 11 je ffffffff814015c4 48 89 18 mov %rbx,(%rax) 48 8b 83 40 02 00 00 mov 0x240(%rbx),%rax [*] c7 40 40 01 00 00 00 movl $0x1,0x40(%rax) With this patch applied, the instruction at [*] is elided, since the store to plane->state->plane is known to not alter the value of plane->state. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Rasmus Villemoes Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kernel.h: add u64_to_user_ptr()

2016-04-30T00:03:49Z

This function had copies in 3 different files. Unify them in kernel.h. Cc: Joe Perches Cc: Andrew Morton Cc: David Airlie Cc: Daniel Vetter Cc: Rob Clark Signed-off-by: Gustavo Padovan Acked-by: Daniel Vetter [drm/i915/] Acked-by: Rob Clark [drm/msm/] Acked-by: Lucas Stach [drm/etinav/] Acked-by: Maarten Lankhorst Signed-off-by: Greg Kroah-Hartman

Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2016-03-24T17:52:25Z

Pull tracing updates from Steven Rostedt: "Nothing major this round. Mostly small clean ups and fixes. Some visible changes: - A new flag was added to distinguish traces done in NMI context. - Preempt tracer now shows functions where preemption is disabled but interrupts are still enabled. Other notes: - Updates were done to function tracing to allow better performance with perf. - Infrastructure code has been added to allow for a new histogram feature for recording live trace event histograms that can be configured by simple user commands. The feature itself was just finished, but needs a round in linux-next before being pulled. This only includes some infrastructure changes that will be needed" * tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits) tracing: Record and show NMI state tracing: Fix trace_printk() to print when not using bprintk() tracing: Remove redundant reset per-CPU buff in irqsoff tracer x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c tracing: Fix crash from reading trace_pipe with sendfile tracing: Have preempt(irqs)off trace preempt disabled functions tracing: Fix return while holding a lock in register_tracer() ftrace: Use kasprintf() in ftrace_profile_tracefs() ftrace: Update dynamic ftrace calls only if necessary ftrace: Make ftrace_hash_rec_enable return update bool tracing: Fix typoes in code comment and printk in trace_nop.c tracing, writeback: Replace cgroup path to cgroup ino tracing: Use flags instead of bool in trigger structure tracing: Add an unreg_all() callback to trigger commands tracing: Add needs_rec flag to event triggers tracing: Add a per-event-trigger 'paused' field tracing: Add get_syscall_name() tracing: Add event record param to trigger_ops.func() tracing: Make event trigger functions available tracing: Make ftrace_event_field checking functions available ...

panic: change nmi_panic from macro to function

2016-03-22T22:36:02Z

Commit 1717f2096b54 ("panic, x86: Fix re-entrance problem due to panic on NMI") and commit 58c5661f2144 ("panic, x86: Allow CPUs to save registers even if looping in NMI context") introduced nmi_panic() which prevents concurrent/recursive execution of panic(). It also saves registers for the crash dump on x86. However, there are some cases where NMI handlers still use panic(). This patch set partially replaces them with nmi_panic() in those cases. Even this patchset is applied, some NMI or similar handlers (e.g. MCE handler) continue to use panic(). This is because I can't test them well and actual problems won't happen. For example, the possibility that normal panic and panic on MCE happen simultaneously is very low. This patch (of 3): Convert nmi_panic() to a proper function and export it instead of exporting internal implementation details to modules, for obvious reasons. Signed-off-by: Hidehiro Kawai Acked-by: Borislav Petkov Acked-by: Michal Nazarewicz Cc: Michal Hocko Cc: Rasmus Villemoes Cc: Nicolas Iooss Cc: Javi Merino Cc: Gobinda Charan Maji Cc: "Steven Rostedt (Red Hat)" Cc: Thomas Gleixner Cc: Vitaly Kuznetsov Cc: HATAYAMA Daisuke Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tracing: Fix trace_printk() to print when not using bprintk()

2016-03-22T22:02:40Z

The trace_printk() code will allocate extra buffers if the compile detects that a trace_printk() is used. To do this, the format of the trace_printk() is saved to the __trace_printk_fmt section, and if that section is bigger than zero, the buffers are allocated (along with a message that this has happened). If trace_printk() uses a format that is not a constant, and thus something not guaranteed to be around when the print happens, the compiler optimizes the fmt out, as it is not used, and the __trace_printk_fmt section is not filled. This means the kernel will not allocate the special buffers needed for the trace_printk() and the trace_printk() will not write anything to the tracing buffer. Adding a "__used" to the variable in the __trace_printk_fmt section will keep it around, even though it is set to NULL. This will keep the string from being printed in the debugfs/tracing/printk_formats section as it is not needed. Reported-by: Vlastimil Babka Fixes: 07d777fe8c398 "tracing: Add percpu buffers for trace_printk()" Cc: stable@vger.kernel.org # v3.5+ Signed-off-by: Steven Rostedt