aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/hardirq.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-04 12:36:54 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-04 12:36:54 -0400
commit6832d9652f395f7d13003e3884942c40f52ac1fa (patch)
tree40555ad5eda9700cb973dac4db136ad97f5e8b19 /include/linux/hardirq.h
parent228abe73ad67665d71eacd6a8a347dd76b0115ae (diff)
parentc2e7fcf53c3cb02b4ada1c66a9bc8a4d97d58aba (diff)
Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers/nohz changes from Ingo Molnar: "It mostly contains fixes and full dynticks off-case optimizations, by Frederic Weisbecker" * 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) nohz: Include local CPU in full dynticks global kick nohz: Optimize full dynticks's sched hooks with static keys nohz: Optimize full dynticks state checks with static keys nohz: Rename a few state variables vtime: Always debug check snapshot source _before_ updating it vtime: Always scale generic vtime accounting results vtime: Optimize full dynticks accounting off case with static keys vtime: Describe overriden functions in dedicated arch headers m68k: hardirq_count() only need preempt_mask.h hardirq: Split preempt count mask definitions context_tracking: Split low level state headers vtime: Fix racy cputime delta update vtime: Remove a few unneeded generic vtime state checks context_tracking: User/kernel broundary cross trace events context_tracking: Optimize context switch off case with static keys context_tracking: Optimize guest APIs off case with static key context_tracking: Optimize main APIs off case with static key context_tracking: Ground setup for static key use context_tracking: Remove full dynticks' hacky dependency on wide context tracking nohz: Only enable context tracking on full dynticks CPUs ...
Diffstat (limited to 'include/linux/hardirq.h')
-rw-r--r--include/linux/hardirq.h117
1 files changed, 1 insertions, 116 deletions
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 05bcc0903766..ccfe17c5c8da 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -1,126 +1,11 @@
1#ifndef LINUX_HARDIRQ_H 1#ifndef LINUX_HARDIRQ_H
2#define LINUX_HARDIRQ_H 2#define LINUX_HARDIRQ_H
3 3
4#include <linux/preempt.h> 4#include <linux/preempt_mask.h>
5#include <linux/lockdep.h> 5#include <linux/lockdep.h>
6#include <linux/ftrace_irq.h> 6#include <linux/ftrace_irq.h>
7#include <linux/vtime.h> 7#include <linux/vtime.h>
8#include <asm/hardirq.h>
9 8
10/*
11 * We put the hardirq and softirq counter into the preemption
12 * counter. The bitmask has the following meaning:
13 *
14 * - bits 0-7 are the preemption count (max preemption depth: 256)
15 * - bits 8-15 are the softirq count (max # of softirqs: 256)
16 *
17 * The hardirq count can in theory reach the same as NR_IRQS.
18 * In reality, the number of nested IRQS is limited to the stack
19 * size as well. For archs with over 1000 IRQS it is not practical
20 * to expect that they will all nest. We give a max of 10 bits for
21 * hardirq nesting. An arch may choose to give less than 10 bits.
22 * m68k expects it to be 8.
23 *
24 * - bits 16-25 are the hardirq count (max # of nested hardirqs: 1024)
25 * - bit 26 is the NMI_MASK
26 * - bit 27 is the PREEMPT_ACTIVE flag
27 *
28 * PREEMPT_MASK: 0x000000ff
29 * SOFTIRQ_MASK: 0x0000ff00
30 * HARDIRQ_MASK: 0x03ff0000
31 * NMI_MASK: 0x04000000
32 */
33#define PREEMPT_BITS 8
34#define SOFTIRQ_BITS 8
35#define NMI_BITS 1
36
37#define MAX_HARDIRQ_BITS 10
38
39#ifndef HARDIRQ_BITS
40# define HARDIRQ_BITS MAX_HARDIRQ_BITS
41#endif
42
43#if HARDIRQ_BITS > MAX_HARDIRQ_BITS
44#error HARDIRQ_BITS too high!
45#endif
46
47#define PREEMPT_SHIFT 0
48#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
49#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
50#define NMI_SHIFT (HARDIRQ_SHIFT + HARDIRQ_BITS)
51
52#define __IRQ_MASK(x) ((1UL << (x))-1)
53
54#define PREEMPT_MASK (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
55#define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
56#define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)
57#define NMI_MASK (__IRQ_MASK(NMI_BITS) << NMI_SHIFT)
58
59#define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT)
60#define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT)
61#define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
62#define NMI_OFFSET (1UL << NMI_SHIFT)
63
64#define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET)
65
66#ifndef PREEMPT_ACTIVE
67#define PREEMPT_ACTIVE_BITS 1
68#define PREEMPT_ACTIVE_SHIFT (NMI_SHIFT + NMI_BITS)
69#define PREEMPT_ACTIVE (__IRQ_MASK(PREEMPT_ACTIVE_BITS) << PREEMPT_ACTIVE_SHIFT)
70#endif
71
72#if PREEMPT_ACTIVE < (1 << (NMI_SHIFT + NMI_BITS))
73#error PREEMPT_ACTIVE is too low!
74#endif
75
76#define hardirq_count() (preempt_count() & HARDIRQ_MASK)
77#define softirq_count() (preempt_count() & SOFTIRQ_MASK)
78#define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \
79 | NMI_MASK))
80
81/*
82 * Are we doing bottom half or hardware interrupt processing?
83 * Are we in a softirq context? Interrupt context?
84 * in_softirq - Are we currently processing softirq or have bh disabled?
85 * in_serving_softirq - Are we currently processing softirq?
86 */
87#define in_irq() (hardirq_count())
88#define in_softirq() (softirq_count())
89#define in_interrupt() (irq_count())
90#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
91
92/*
93 * Are we in NMI context?
94 */
95#define in_nmi() (preempt_count() & NMI_MASK)
96
97#if defined(CONFIG_PREEMPT_COUNT)
98# define PREEMPT_CHECK_OFFSET 1
99#else
100# define PREEMPT_CHECK_OFFSET 0
101#endif
102
103/*
104 * Are we running in atomic context? WARNING: this macro cannot
105 * always detect atomic context; in particular, it cannot know about
106 * held spinlocks in non-preemptible kernels. Thus it should not be
107 * used in the general case to determine whether sleeping is possible.
108 * Do not use in_atomic() in driver code.
109 */
110#define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != 0)
111
112/*
113 * Check whether we were atomic before we did preempt_disable():
114 * (used by the scheduler, *after* releasing the kernel lock)
115 */
116#define in_atomic_preempt_off() \
117 ((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_CHECK_OFFSET)
118
119#ifdef CONFIG_PREEMPT_COUNT
120# define preemptible() (preempt_count() == 0 && !irqs_disabled())
121#else
122# define preemptible() 0
123#endif
124 9
125#if defined(CONFIG_SMP) || defined(CONFIG_GENERIC_HARDIRQS) 10#if defined(CONFIG_SMP) || defined(CONFIG_GENERIC_HARDIRQS)
126extern void synchronize_irq(unsigned int irq); 11extern void synchronize_irq(unsigned int irq);