msm: qdss: provide an api to force disable qdss sink
Introduce a new api (qdss_disable_sink) that can be called from atomic
or non-atomic context to force disable the current qdss sink(s).
This api will be used as a way to force stop the sink (eg. etb) from
accepting any more trace data and hence avoid being polluted with trace
data that is uninteresting after an event of interest (eg. userspace
process crash) has occured.
Change-Id: I2a474ba9f51275aa3fa77ee35c39149663dfb03c
Signed-off-by: Pratik Patel <pratikp@codeaurora.org>
diff --git a/arch/arm/mach-msm/include/mach/qdss.h b/arch/arm/mach-msm/include/mach/qdss.h
index 3b236b8..05d8577 100644
--- a/arch/arm/mach-msm/include/mach/qdss.h
+++ b/arch/arm/mach-msm/include/mach/qdss.h
@@ -30,6 +30,7 @@
extern void qdss_put(struct qdss_source *src);
extern int qdss_enable(struct qdss_source *src);
extern void qdss_disable(struct qdss_source *src);
+extern void qdss_disable_sink(void);
extern int qdss_clk_enable(void);
extern void qdss_clk_disable(void);
#else
@@ -37,6 +38,7 @@
static inline void qdss_put(struct qdss_source *src) {}
static inline int qdss_enable(struct qdss_source *src) { return -ENOSYS; }
static inline void qdss_disable(struct qdss_source *src) {}
+static inline void qdss_disable_sink(void) {}
static inline int qdss_clk_enable(void) { return -ENOSYS; }
static inline void qdss_clk_disable(void) {}
#endif
diff --git a/arch/arm/mach-msm/qdss.c b/arch/arm/mach-msm/qdss.c
index cfe65ad..0cc3ca5 100644
--- a/arch/arm/mach-msm/qdss.c
+++ b/arch/arm/mach-msm/qdss.c
@@ -175,6 +175,26 @@
EXPORT_SYMBOL(qdss_disable);
/**
+ * qdss_disable_sink - force disable the current qdss sink(s)
+ *
+ * Force disable the current qdss sink(s) to stop the sink from accepting any
+ * trace generated subsequent to this call. This function should only be used
+ * as a way to stop the sink from getting polluted with trace data that is
+ * uninteresting after an event of interest has occured.
+ *
+ * CONTEXT:
+ * Can be called from atomic or non-atomic context.
+ */
+void qdss_disable_sink(void)
+{
+ if ((qdss.pdata)->afamily) {
+ etb_dump();
+ etb_disable();
+ }
+}
+EXPORT_SYMBOL(qdss_disable_sink);
+
+/**
* qdss_clk_enable - enable qdss clocks
*
* Enables qdss clocks via RPM if they aren't already enabled, otherwise