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>

4 files changed, 110 insertions, 66 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fb186b9ddf51..31c90fec4158 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1925,8 +1925,16 @@ ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
          * when we are adding another op to the rec or removing the
          * current one. Thus, if the op is being added, we can
          * ignore it because it hasn't attached itself to the rec
-         * yet. That means we just need to find the op that has a
-         * trampoline and is not beeing added.
+         * yet.
+         *
+         * If an ops is being modified (hooking to different functions)
+         * then we don't care about the new functions that are being
+         * added, just the old ones (that are probably being removed).
+         *
+         * If we are adding an ops to a function that already is using
+         * a trampoline, it needs to be removed (trampolines are only
+         * for single ops connected), then an ops that is not being
+         * modified also needs to be checked.
          */
         do_for_each_ftrace_op(op, ftrace_ops_list) {
 
@@ -1940,17 +1948,23 @@ ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
                 if (op->flags & FTRACE_OPS_FL_ADDING)
                         continue;
 
+
                 /*
-                 * If the ops is not being added and has a trampoline,
-                 * then it must be the one that we want!
+                 * If the ops is being modified and is in the old
+                 * hash, then it is probably being removed from this
+                 * function.
                  */
-                if (hash_contains_ip(ip, op->func_hash))
-                        return op;
-
-                /* If the ops is being modified, it may be in the old hash. */
                 if ((op->flags & FTRACE_OPS_FL_MODIFYING) &&
                     hash_contains_ip(ip, &op->old_hash))
                         return op;
+                /*
+                 * If the ops is not being added or modified, and it's
+                 * in its normal filter hash, then this must be the one
+                 * we want!
+                 */
+                if (!(op->flags & FTRACE_OPS_FL_MODIFYING) &&
+                    hash_contains_ip(ip, op->func_hash))
+                        return op;
 
         } while_for_each_ftrace_op(op);
 
@@ -2293,10 +2307,13 @@ static void ftrace_run_update_code(int command)
         FTRACE_WARN_ON(ret);
 }
 
-static void ftrace_run_modify_code(struct ftrace_ops *ops, int command)
+static void ftrace_run_modify_code(struct ftrace_ops *ops, int command,
+                                   struct ftrace_hash *old_hash)
 {
         ops->flags |= FTRACE_OPS_FL_MODIFYING;
+        ops->old_hash.filter_hash = old_hash;
         ftrace_run_update_code(command);
+        ops->old_hash.filter_hash = NULL;
         ops->flags &= ~FTRACE_OPS_FL_MODIFYING;
 }
 
@@ -3340,7 +3357,7 @@ static struct ftrace_ops trace_probe_ops __read_mostly =
 
 static int ftrace_probe_registered;
 
-static void __enable_ftrace_function_probe(void)
+static void __enable_ftrace_function_probe(struct ftrace_hash *old_hash)
 {
         int ret;
         int i;
@@ -3348,7 +3365,8 @@ static void __enable_ftrace_function_probe(void)
         if (ftrace_probe_registered) {
                 /* still need to update the function call sites */
                 if (ftrace_enabled)
-                        ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS);
+                        ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS,
+                                               old_hash);
                 return;
         }
 
@@ -3477,13 +3495,14 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
         } while_for_each_ftrace_rec();
 
         ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+
+        __enable_ftrace_function_probe(old_hash);
+
         if (!ret)
                 free_ftrace_hash_rcu(old_hash);
         else
                 count = ret;
 
-        __enable_ftrace_function_probe();
-
  out_unlock:
         mutex_unlock(&ftrace_lock);
  out:
@@ -3764,10 +3783,11 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
         return add_hash_entry(hash, ip);
 }
 
-static void ftrace_ops_update_code(struct ftrace_ops *ops)
+static void ftrace_ops_update_code(struct ftrace_ops *ops,
+                                   struct ftrace_hash *old_hash)
 {
         if (ops->flags & FTRACE_OPS_FL_ENABLED && ftrace_enabled)
-                ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS);
+                ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash);
 }
 
 static int
@@ -3813,7 +3833,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
         old_hash = *orig_hash;
         ret = ftrace_hash_move(ops, enable, orig_hash, hash);
         if (!ret) {
-                ftrace_ops_update_code(ops);
+                ftrace_ops_update_code(ops, old_hash);
                 free_ftrace_hash_rcu(old_hash);
         }
         mutex_unlock(&ftrace_lock);
@@ -4058,7 +4078,7 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
                 ret = ftrace_hash_move(iter->ops, filter_hash,
                                        orig_hash, iter->hash);
                 if (!ret) {
-                        ftrace_ops_update_code(iter->ops);
+                        ftrace_ops_update_code(iter->ops, old_hash);
                         free_ftrace_hash_rcu(old_hash);
                 }
                 mutex_unlock(&ftrace_lock);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 2d75c94ae87d..a56e07c8d15b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -538,16 +538,18 @@ static void rb_wake_up_waiters(struct irq_work *work)
  * ring_buffer_wait - wait for input to the ring buffer
  * @buffer: buffer to wait on
  * @cpu: the cpu buffer to wait on
+ * @full: wait until a full page is available, if @cpu != RING_BUFFER_ALL_CPUS
  *
  * If @cpu == RING_BUFFER_ALL_CPUS then the task will wake up as soon
  * as data is added to any of the @buffer's cpu buffers. Otherwise
  * it will wait for data to be added to a specific cpu buffer.
  */
-int ring_buffer_wait(struct ring_buffer *buffer, int cpu)
+int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full)
 {
-        struct ring_buffer_per_cpu *cpu_buffer;
+        struct ring_buffer_per_cpu *uninitialized_var(cpu_buffer);
         DEFINE_WAIT(wait);
         struct rb_irq_work *work;
+        int ret = 0;
 
         /*
          * Depending on what the caller is waiting for, either any
@@ -564,36 +566,61 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu)
         }
 
 
-        prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE);
+        while (true) {
+                prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE);
 
-        /*
-         * The events can happen in critical sections where
-         * checking a work queue can cause deadlocks.
-         * After adding a task to the queue, this flag is set
-         * only to notify events to try to wake up the queue
-         * using irq_work.
-         *
-         * We don't clear it even if the buffer is no longer
-         * empty. The flag only causes the next event to run
-         * irq_work to do the work queue wake up. The worse
-         * that can happen if we race with !trace_empty() is that
-         * an event will cause an irq_work to try to wake up
-         * an empty queue.
-         *
-         * There's no reason to protect this flag either, as
-         * the work queue and irq_work logic will do the necessary
-         * synchronization for the wake ups. The only thing
-         * that is necessary is that the wake up happens after
-         * a task has been queued. It's OK for spurious wake ups.
-         */
-        work->waiters_pending = true;
+                /*
+                 * The events can happen in critical sections where
+                 * checking a work queue can cause deadlocks.
+                 * After adding a task to the queue, this flag is set
+                 * only to notify events to try to wake up the queue
+                 * using irq_work.
+                 *
+                 * We don't clear it even if the buffer is no longer
+                 * empty. The flag only causes the next event to run
+                 * irq_work to do the work queue wake up. The worse
+                 * that can happen if we race with !trace_empty() is that
+                 * an event will cause an irq_work to try to wake up
+                 * an empty queue.
+                 *
+                 * There's no reason to protect this flag either, as
+                 * the work queue and irq_work logic will do the necessary
+                 * synchronization for the wake ups. The only thing
+                 * that is necessary is that the wake up happens after
+                 * a task has been queued. It's OK for spurious wake ups.
+                 */
+                work->waiters_pending = true;
+
+                if (signal_pending(current)) {
+                        ret = -EINTR;
+                        break;
+                }
+
+                if (cpu == RING_BUFFER_ALL_CPUS && !ring_buffer_empty(buffer))
+                        break;
+
+                if (cpu != RING_BUFFER_ALL_CPUS &&
+                    !ring_buffer_empty_cpu(buffer, cpu)) {
+                        unsigned long flags;
+                        bool pagebusy;
+
+                        if (!full)
+                                break;
+
+                        raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+                        pagebusy = cpu_buffer->reader_page == cpu_buffer->commit_page;
+                        raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+
+                        if (!pagebusy)
+                                break;
+                }
 
-        if ((cpu == RING_BUFFER_ALL_CPUS && ring_buffer_empty(buffer)) ||
-            (cpu != RING_BUFFER_ALL_CPUS && ring_buffer_empty_cpu(buffer, cpu)))
                 schedule();
+        }
 
         finish_wait(&work->waiters, &wait);
-        return 0;
+
+        return ret;
 }
 
 /**
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8a528392b1f4..92f4a6cee172 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1076,13 +1076,14 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
 }
 #endif /* CONFIG_TRACER_MAX_TRACE */
 
-static int wait_on_pipe(struct trace_iterator *iter)
+static int wait_on_pipe(struct trace_iterator *iter, bool full)
 {
         /* Iterators are static, they should be filled or empty */
         if (trace_buffer_iter(iter, iter->cpu_file))
                 return 0;
 
-        return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file);
+        return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file,
+                                full);
 }
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
@@ -4434,15 +4435,12 @@ static int tracing_wait_pipe(struct file *filp)
 
                 mutex_unlock(&iter->mutex);
 
-                ret = wait_on_pipe(iter);
+                ret = wait_on_pipe(iter, false);
 
                 mutex_lock(&iter->mutex);
 
                 if (ret)
                         return ret;
-
-                if (signal_pending(current))
-                        return -EINTR;
         }
 
         return 1;
@@ -5372,16 +5370,12 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
                                 goto out_unlock;
                         }
                         mutex_unlock(&trace_types_lock);
-                        ret = wait_on_pipe(iter);
+                        ret = wait_on_pipe(iter, false);
                         mutex_lock(&trace_types_lock);
                         if (ret) {
                                 size = ret;
                                 goto out_unlock;
                         }
-                        if (signal_pending(current)) {
-                                size = -EINTR;
-                                goto out_unlock;
-                        }
                         goto again;
                 }
                 size = 0;
@@ -5500,7 +5494,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
         };
         struct buffer_ref *ref;
         int entries, size, i;
-        ssize_t ret;
+        ssize_t ret = 0;
 
         mutex_lock(&trace_types_lock);
 
@@ -5538,13 +5532,16 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 int r;
 
                 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
-                if (!ref)
+                if (!ref) {
+                        ret = -ENOMEM;
                         break;
+                }
 
                 ref->ref = 1;
                 ref->buffer = iter->trace_buffer->buffer;
                 ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
                 if (!ref->page) {
+                        ret = -ENOMEM;
                         kfree(ref);
                         break;
                 }
@@ -5582,19 +5579,19 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 
         /* did we read anything? */
         if (!spd.nr_pages) {
+                if (ret)
+                        goto out;
+
                 if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) {
                         ret = -EAGAIN;
                         goto out;
                 }
                 mutex_unlock(&trace_types_lock);
-                ret = wait_on_pipe(iter);
+                ret = wait_on_pipe(iter, true);
                 mutex_lock(&trace_types_lock);
                 if (ret)
                         goto out;
-                if (signal_pending(current)) {
-                        ret = -EINTR;
-                        goto out;
-                }
+
                 goto again;
         }
 
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 4dc8b79c5f75..29228c4d5696 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -313,7 +313,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
         int size;
 
         syscall_nr = trace_get_syscall_nr(current, regs);
-        if (syscall_nr < 0)
+        if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
                 return;
 
         /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */
@@ -360,7 +360,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
         int syscall_nr;
 
         syscall_nr = trace_get_syscall_nr(current, regs);
-        if (syscall_nr < 0)
+        if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
                 return;
 
         /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */
@@ -567,7 +567,7 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
         int size;
 
         syscall_nr = trace_get_syscall_nr(current, regs);
-        if (syscall_nr < 0)
+        if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
                 return;
         if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
                 return;
@@ -641,7 +641,7 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
         int size;
 
         syscall_nr = trace_get_syscall_nr(current, regs);
-        if (syscall_nr < 0)
+        if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
                 return;
         if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
                 return;