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Diffstat (limited to 'kernel')
-rw-r--r--kernel/dma/swiotlb.c29
-rw-r--r--kernel/trace/ring_buffer.c13
-rw-r--r--kernel/trace/trace.c28
-rw-r--r--kernel/trace/trace_events_synth.c19
-rw-r--r--kernel/trace/trace_osnoise.c4
5 files changed, 61 insertions, 32 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 03e3251cd9d2..5b919ef832b6 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -625,8 +625,8 @@ static int swiotlb_do_find_slots(struct device *dev, int area_index,
unsigned int iotlb_align_mask =
dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1);
unsigned int nslots = nr_slots(alloc_size), stride;
- unsigned int index, wrap, count = 0, i;
unsigned int offset = swiotlb_align_offset(dev, orig_addr);
+ unsigned int index, slots_checked, count = 0, i;
unsigned long flags;
unsigned int slot_base;
unsigned int slot_index;
@@ -635,29 +635,34 @@ static int swiotlb_do_find_slots(struct device *dev, int area_index,
BUG_ON(area_index >= mem->nareas);
/*
+ * For allocations of PAGE_SIZE or larger only look for page aligned
+ * allocations.
+ */
+ if (alloc_size >= PAGE_SIZE)
+ iotlb_align_mask &= PAGE_MASK;
+ iotlb_align_mask &= alloc_align_mask;
+
+ /*
* For mappings with an alignment requirement don't bother looping to
- * unaligned slots once we found an aligned one. For allocations of
- * PAGE_SIZE or larger only look for page aligned allocations.
+ * unaligned slots once we found an aligned one.
*/
stride = (iotlb_align_mask >> IO_TLB_SHIFT) + 1;
- if (alloc_size >= PAGE_SIZE)
- stride = max(stride, stride << (PAGE_SHIFT - IO_TLB_SHIFT));
- stride = max(stride, (alloc_align_mask >> IO_TLB_SHIFT) + 1);
spin_lock_irqsave(&area->lock, flags);
if (unlikely(nslots > mem->area_nslabs - area->used))
goto not_found;
slot_base = area_index * mem->area_nslabs;
- index = wrap = wrap_area_index(mem, ALIGN(area->index, stride));
+ index = area->index;
- do {
+ for (slots_checked = 0; slots_checked < mem->area_nslabs; ) {
slot_index = slot_base + index;
if (orig_addr &&
(slot_addr(tbl_dma_addr, slot_index) &
iotlb_align_mask) != (orig_addr & iotlb_align_mask)) {
index = wrap_area_index(mem, index + 1);
+ slots_checked++;
continue;
}
@@ -673,7 +678,8 @@ static int swiotlb_do_find_slots(struct device *dev, int area_index,
goto found;
}
index = wrap_area_index(mem, index + stride);
- } while (index != wrap);
+ slots_checked += stride;
+ }
not_found:
spin_unlock_irqrestore(&area->lock, flags);
@@ -693,10 +699,7 @@ found:
/*
* Update the indices to avoid searching in the next round.
*/
- if (index + nslots < mem->area_nslabs)
- area->index = index + nslots;
- else
- area->index = 0;
+ area->index = wrap_area_index(mem, index + nslots);
area->used += nslots;
spin_unlock_irqrestore(&area->lock, flags);
return slot_index;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index c6f47b6cfd5f..76a2d91eecad 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -3098,6 +3098,10 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
if (RB_WARN_ON(cpu_buffer,
rb_is_reader_page(cpu_buffer->tail_page)))
return;
+ /*
+ * No need for a memory barrier here, as the update
+ * of the tail_page did it for this page.
+ */
local_set(&cpu_buffer->commit_page->page->commit,
rb_page_write(cpu_buffer->commit_page));
rb_inc_page(&cpu_buffer->commit_page);
@@ -3107,6 +3111,8 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
while (rb_commit_index(cpu_buffer) !=
rb_page_write(cpu_buffer->commit_page)) {
+ /* Make sure the readers see the content of what is committed. */
+ smp_wmb();
local_set(&cpu_buffer->commit_page->page->commit,
rb_page_write(cpu_buffer->commit_page));
RB_WARN_ON(cpu_buffer,
@@ -4684,7 +4690,12 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
/*
* Make sure we see any padding after the write update
- * (see rb_reset_tail())
+ * (see rb_reset_tail()).
+ *
+ * In addition, a writer may be writing on the reader page
+ * if the page has not been fully filled, so the read barrier
+ * is also needed to make sure we see the content of what is
+ * committed by the writer (see rb_set_commit_to_write()).
*/
smp_rmb();
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 937e9676dfd4..36a6037823cd 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1149,22 +1149,22 @@ static void tracing_snapshot_instance_cond(struct trace_array *tr,
unsigned long flags;
if (in_nmi()) {
- internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n");
- internal_trace_puts("*** snapshot is being ignored ***\n");
+ trace_array_puts(tr, "*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n");
+ trace_array_puts(tr, "*** snapshot is being ignored ***\n");
return;
}
if (!tr->allocated_snapshot) {
- internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n");
- internal_trace_puts("*** stopping trace here! ***\n");
- tracing_off();
+ trace_array_puts(tr, "*** SNAPSHOT NOT ALLOCATED ***\n");
+ trace_array_puts(tr, "*** stopping trace here! ***\n");
+ tracer_tracing_off(tr);
return;
}
/* Note, snapshot can not be used when the tracer uses it */
if (tracer->use_max_tr) {
- internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n");
- internal_trace_puts("*** Can not use snapshot (sorry) ***\n");
+ trace_array_puts(tr, "*** LATENCY TRACER ACTIVE ***\n");
+ trace_array_puts(tr, "*** Can not use snapshot (sorry) ***\n");
return;
}
@@ -9516,6 +9516,7 @@ static int __remove_instance(struct trace_array *tr)
tracefs_remove(tr->dir);
free_percpu(tr->last_func_repeats);
free_trace_buffers(tr);
+ clear_tracing_err_log(tr);
for (i = 0; i < tr->nr_topts; i++) {
kfree(tr->topts[i].topts);
@@ -10393,19 +10394,20 @@ out:
void __init ftrace_boot_snapshot(void)
{
+#ifdef CONFIG_TRACER_MAX_TRACE
struct trace_array *tr;
- if (snapshot_at_boot) {
- tracing_snapshot();
- internal_trace_puts("** Boot snapshot taken **\n");
- }
+ if (!snapshot_at_boot)
+ return;
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (tr == &global_trace)
+ if (!tr->allocated_snapshot)
continue;
- trace_array_puts(tr, "** Boot snapshot taken **\n");
+
tracing_snapshot_instance(tr);
+ trace_array_puts(tr, "** Boot snapshot taken **\n");
}
+#endif
}
void __init early_trace_init(void)
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index 46d0abb32d0f..f0ff730125bf 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -44,14 +44,21 @@ enum { ERRORS };
static const char *err_text[] = { ERRORS };
+DEFINE_MUTEX(lastcmd_mutex);
static char *last_cmd;
static int errpos(const char *str)
{
+ int ret = 0;
+
+ mutex_lock(&lastcmd_mutex);
if (!str || !last_cmd)
- return 0;
+ goto out;
- return err_pos(last_cmd, str);
+ ret = err_pos(last_cmd, str);
+ out:
+ mutex_unlock(&lastcmd_mutex);
+ return ret;
}
static void last_cmd_set(const char *str)
@@ -59,18 +66,22 @@ static void last_cmd_set(const char *str)
if (!str)
return;
+ mutex_lock(&lastcmd_mutex);
kfree(last_cmd);
-
last_cmd = kstrdup(str, GFP_KERNEL);
+ mutex_unlock(&lastcmd_mutex);
}
static void synth_err(u8 err_type, u16 err_pos)
{
+ mutex_lock(&lastcmd_mutex);
if (!last_cmd)
- return;
+ goto out;
tracing_log_err(NULL, "synthetic_events", last_cmd, err_text,
err_type, err_pos);
+ out:
+ mutex_unlock(&lastcmd_mutex);
}
static int create_synth_event(const char *raw_command);
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index 9176bb7a9bb4..4496975f2029 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -1296,7 +1296,7 @@ static void notify_new_max_latency(u64 latency)
rcu_read_lock();
list_for_each_entry_rcu(inst, &osnoise_instances, list) {
tr = inst->tr;
- if (tr->max_latency < latency) {
+ if (tracer_tracing_is_on(tr) && tr->max_latency < latency) {
tr->max_latency = latency;
latency_fsnotify(tr);
}
@@ -1738,6 +1738,8 @@ static int timerlat_main(void *data)
trace_timerlat_sample(&s);
+ notify_new_max_latency(diff);
+
timerlat_dump_stack(time_to_us(diff));
tlat->tracing_thread = false;