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authorDaniel Vetter <daniel.vetter@ffwll.ch>2014-11-19 12:14:57 -0500
committerDaniel Vetter <daniel.vetter@ffwll.ch>2014-11-19 12:17:38 -0500
commit54499b2a926964b6b671fd03dcdc83c444b8f467 (patch)
treeba57cd39218554850e4b920747b9e71f1f9842ee /kernel/context_tracking.c
parent2eb5252e2fffc52745a672152c7df597f4041045 (diff)
parent0485c9dc24ec0939b42ca5104c0373297506b555 (diff)
Merge tag 'drm-intel-fixes-2014-11-19' into drm-intel-next-queued
So with all the code movement and extraction in intel_pm.c in -next git is hopelessly confused with commit 2208d655a91f9879bd9a39ff9df05dd668b3512c Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Fri Nov 14 09:25:29 2014 +0100 drm/i915: drop WaSetupGtModeTdRowDispatch:snb from -fixes. Worse even small changes in -next move around the conflict context so rerere is equally useless. Let's just backmerge and be done with it. Conflicts: drivers/gpu/drm/i915/i915_drv.c drivers/gpu/drm/i915/intel_pm.c Except for git getting lost no tricky conflicts really. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'kernel/context_tracking.c')
-rw-r--r--kernel/context_tracking.c40
1 files changed, 0 insertions, 40 deletions
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 5664985c46a0..937ecdfdf258 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -107,46 +107,6 @@ void context_tracking_user_enter(void)
107} 107}
108NOKPROBE_SYMBOL(context_tracking_user_enter); 108NOKPROBE_SYMBOL(context_tracking_user_enter);
109 109
110#ifdef CONFIG_PREEMPT
111/**
112 * preempt_schedule_context - preempt_schedule called by tracing
113 *
114 * The tracing infrastructure uses preempt_enable_notrace to prevent
115 * recursion and tracing preempt enabling caused by the tracing
116 * infrastructure itself. But as tracing can happen in areas coming
117 * from userspace or just about to enter userspace, a preempt enable
118 * can occur before user_exit() is called. This will cause the scheduler
119 * to be called when the system is still in usermode.
120 *
121 * To prevent this, the preempt_enable_notrace will use this function
122 * instead of preempt_schedule() to exit user context if needed before
123 * calling the scheduler.
124 */
125asmlinkage __visible void __sched notrace preempt_schedule_context(void)
126{
127 enum ctx_state prev_ctx;
128
129 if (likely(!preemptible()))
130 return;
131
132 /*
133 * Need to disable preemption in case user_exit() is traced
134 * and the tracer calls preempt_enable_notrace() causing
135 * an infinite recursion.
136 */
137 preempt_disable_notrace();
138 prev_ctx = exception_enter();
139 preempt_enable_no_resched_notrace();
140
141 preempt_schedule();
142
143 preempt_disable_notrace();
144 exception_exit(prev_ctx);
145 preempt_enable_notrace();
146}
147EXPORT_SYMBOL_GPL(preempt_schedule_context);
148#endif /* CONFIG_PREEMPT */
149
150/** 110/**
151 * context_tracking_user_exit - Inform the context tracking that the CPU is 111 * context_tracking_user_exit - Inform the context tracking that the CPU is
152 * exiting userspace mode and entering the kernel. 112 * exiting userspace mode and entering the kernel.