summaryrefslogtreecommitdiff
path: root/kernel/trace/trace.h
diff options
context:
space:
mode:
authorMark Brown <broonie@kernel.org>2020-12-10 13:30:11 +0000
committerMark Brown <broonie@kernel.org>2020-12-10 13:30:11 +0000
commit49ab19a4a51a31cb06992386cec4be82ebca5a2d (patch)
treede7d31ec7ded2c8ab8dbdfe5a55fa283068023d0 /kernel/trace/trace.h
parentb0dfd948379c79b8754e224e29b99d30ce0d79b8 (diff)
parent3b25f337929e73232f0aa990cd68a129f53652e2 (diff)
Merge series "spi: spi-geni-qcom: Use gpio descriptors for CS" from Stephen Boyd <swboyd@chromium.org>:
Collected patches from the two series below and associated tags so they can be merged in one pile through the spi tree. Merry December! SPI: https://lore.kernel.org/r/20201202214935.1114381-1-swboyd@chromium.org cros-ec: https://lore.kernel.org/r/20201203011649.1405292-1-swboyd@chromium.org Cc: Akash Asthana <akashast@codeaurora.org> Cc: Simon Glass <sjg@chromium.org> Cc: Gwendal Grignou <gwendal@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Alexandru M Stan <amstan@chromium.org> Stephen Boyd (3): platform/chrome: cros_ec_spi: Don't overwrite spi::mode platform/chrome: cros_ec_spi: Drop bits_per_word assignment spi: spi-geni-qcom: Use the new method of gpio CS control drivers/platform/chrome/cros_ec_spi.c | 2 -- drivers/spi/spi-geni-qcom.c | 1 + 2 files changed, 1 insertion(+), 2 deletions(-) base-commit: b65054597872ce3aefbc6a666385eabdf9e288da -- https://chromeos.dev
Diffstat (limited to 'kernel/trace/trace.h')
-rw-r--r--kernel/trace/trace.h26
1 files changed, 23 insertions, 3 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index f3f5e77123ad..1dadef445cd1 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -637,6 +637,12 @@ enum {
* function is called to clear it.
*/
TRACE_GRAPH_NOTRACE_BIT,
+
+ /*
+ * When transitioning between context, the preempt_count() may
+ * not be correct. Allow for a single recursion to cover this case.
+ */
+ TRACE_TRANSITION_BIT,
};
#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
@@ -691,14 +697,27 @@ static __always_inline int trace_test_and_set_recursion(int start, int max)
return 0;
bit = trace_get_context_bit() + start;
- if (unlikely(val & (1 << bit)))
- return -1;
+ if (unlikely(val & (1 << bit))) {
+ /*
+ * It could be that preempt_count has not been updated during
+ * a switch between contexts. Allow for a single recursion.
+ */
+ bit = TRACE_TRANSITION_BIT;
+ if (trace_recursion_test(bit))
+ return -1;
+ trace_recursion_set(bit);
+ barrier();
+ return bit + 1;
+ }
+
+ /* Normal check passed, clear the transition to allow it again */
+ trace_recursion_clear(TRACE_TRANSITION_BIT);
val |= 1 << bit;
current->trace_recursion = val;
barrier();
- return bit;
+ return bit + 1;
}
static __always_inline void trace_clear_recursion(int bit)
@@ -708,6 +727,7 @@ static __always_inline void trace_clear_recursion(int bit)
if (!bit)
return;
+ bit--;
bit = 1 << bit;
val &= ~bit;