xtensa: add irq flags trace support

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

2 files changed, 35 insertions, 0 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 13280f2780c8..3eb543eacaa0 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -55,6 +55,9 @@ source "kernel/Kconfig.freezer"
 config STACKTRACE_SUPPORT
         def_bool y
 
+config TRACE_IRQFLAGS_SUPPORT
+        def_bool y
+
 config MMU
         def_bool n
 
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 63845f950792..3729b48d798d 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -389,6 +389,22 @@ common_exception:
 
         save_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT
         
+#ifdef CONFIG_TRACE_IRQFLAGS
+        l32i    a4, a1, PT_DEPC
+        /* Double exception means we came here with an exception
+         * while PS.EXCM was set, i.e. interrupts disabled.
+         */
+        bgeui   a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f
+        l32i    a4, a1, PT_EXCCAUSE
+        bnei    a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f
+        /* We came here with an interrupt means interrupts were enabled
+         * and we've just disabled them.
+         */
+        movi    a4, trace_hardirqs_off
+        callx4  a4
+1:
+#endif
+
         /* Go to second-level dispatcher. Set up parameters to pass to the
          * exception handler and call the exception handler.
          */
@@ -407,6 +423,22 @@ common_exception:
         .global common_exception_return
 common_exception_return:
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+        l32i    a4, a1, PT_DEPC
+        /* Double exception means we came here with an exception
+         * while PS.EXCM was set, i.e. interrupts disabled.
+         */
+        bgeui   a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f
+        l32i    a4, a1, PT_EXCCAUSE
+        bnei    a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f
+        /* We came here with an interrupt means interrupts were enabled
+         * and we'll reenable them on return.
+         */
+        movi    a4, trace_hardirqs_on
+        callx4  a4
+1:
+#endif
+
         /* Jump if we are returning from kernel exceptions. */
 
 1:      l32i    a3, a1, PT_PS