target-s390x: PER instruction-fetch event support

For the PER instruction-fetch, we can't use the QEMU breakpoint
infrastructure as it triggers for a single address and not a full
address range, and as it actually stop before the instruction and
not before.

We therefore call an helper with the just fetched instruction address,
which check if the address is within the PER address range. If it is
the case, an event is recorded and will be signaled through an
exception.

Note that we implement here the PER-3 behaviour, that is an invalid
opcode is not considered as an instruction fetch. Without PER-3 this
behavious is undefined.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/target-s390x/helper.h b/target-s390x/helper.h
index 89197cb674d602575c99a3f04fa80e47179c058c..7e06119e99fa4d36692fc1be7a2603536a3435de 100644 (file)
--- a/target-s390x/helper.h
+++ b/target-s390x/helper.h
@@ -118,6 +118,7 @@ DEF_HELPER_FLAGS_3(stura, TCG_CALL_NO_WG, void, env, i64, i64)
 DEF_HELPER_FLAGS_3(sturg, TCG_CALL_NO_WG, void, env, i64, i64)
 DEF_HELPER_1(per_check_exception, void, env)
 DEF_HELPER_FLAGS_3(per_branch, TCG_CALL_NO_RWG, void, env, i64, i64)
+DEF_HELPER_FLAGS_2(per_ifetch, TCG_CALL_NO_RWG, void, env, i64)
 
 DEF_HELPER_2(xsch, void, env, i64)
 DEF_HELPER_2(csch, void, env, i64)

diff --git a/target-s390x/misc_helper.c b/target-s390x/misc_helper.c
index bc28f9d13da691e72c5a8385dfff158a03a994a3..73d01935be1ce101821aa50645b5b555a03c7cf5 100644 (file)
--- a/target-s390x/misc_helper.c
+++ b/target-s390x/misc_helper.c
@@ -619,4 +619,12 @@ void HELPER(per_branch)(CPUS390XState *env, uint64_t from, uint64_t to)
         }
     }
 }
+
+void HELPER(per_ifetch)(CPUS390XState *env, uint64_t addr)
+{
+    if ((env->cregs[9] & PER_CR9_EVENT_IFETCH) && get_per_in_range(env, addr)) {
+        env->per_address = addr;
+        env->per_perc_atmid = PER_CODE_EVENT_IFETCH | get_per_atmid(env);
+    }
+}
 #endif

diff --git a/target-s390x/translate.c b/target-s390x/translate.c
index 0387806b985acad52330eaaf687ac2b08b94e6cf..d69fb5cb6ceaeb22ecec8af61ec2555f802ffeef 100644 (file)
--- a/target-s390x/translate.c
+++ b/target-s390x/translate.c
@@ -5187,6 +5187,14 @@ static ExitStatus translate_one(CPUS390XState *env, DisasContext *s)
         return EXIT_NORETURN;
     }
 
+#ifndef CONFIG_USER_ONLY
+    if (s->tb->flags & FLAG_MASK_PER) {
+        TCGv_i64 addr = tcg_const_i64(s->pc);
+        gen_helper_per_ifetch(cpu_env, addr);
+        tcg_temp_free_i64(addr);
+    }
+#endif
+
     /* Check for insn specification exceptions.  */
     if (insn->spec) {
         int spec = insn->spec, excp = 0, r;