more documentation about the simcall mechanism

diff --git a/src/simix/simcalls.in b/src/simix/simcalls.in
index a2d8711..22578fd 100644 (file)
--- a/src/simix/simcalls.in
+++ b/src/simix/simcalls.in
@@ -6,12 +6,38 @@
 # CallType handler? name (resulttype,resultcast) (arg0name,arg0type,arg0cast) (arg1name,arg1type,arg1cast)
 
 # CallType must be one of the three:
 # CallType handler? name (resulttype,resultcast) (arg0name,arg0type,arg0cast) (arg1name,arg1type,arg1cast)
 
 # CallType must be one of the three:

-#  - Func: returning a value immediately
-#  - Blck: Blocking call that does not return in the same scheduling round
+#
+#  - Func: returning a value immediately (within the same scheduling round)
+#    examples: all getters that only retrieve informations with no side effect
+#

 #  - Proc: not returning any value (but doing so immediately) 
 #  - Proc: not returning any value (but doing so immediately) 

+#    examples: all setters, *_cancel 
+#
+#  - Blck: Blocking call that does not return in the same scheduling round.
+#    The answer requires some interaction with SURF, even if this can
+#    still occure at the same timestamp under some circonstances (eg
+#    if the surf_action cannot start because of resources that are down)
+#    examples: things that last some time (communicate, execute, mutex_lock)
+#
+#    In a perfect world, these answers would also be handled by the
+#    script, but we are not there yet. Instead, the answer is manually
+#    generated in one of the SIMIX_post_*() functions, that are called
+#    when we unpack the done and failed actions returned by surf after
+#    a surf simulation round. Weird things happen if you forget to
+#    answer a given simcall in there...
+
+

 
 # Handler? is either "H" if we need to generate a handler or "-" if we should go without handlers
 
 
 # Handler? is either "H" if we need to generate a handler or "-" if we should go without handlers
 

+# I wish we could completely remove the handlers as their only use is
+# to adapt the interface between the exported symbol that is visible
+# by the user applications and the internal symbol that is implemented 
+# by the kernel. 
+# The only remaining use of that mechanism is to add the caller
+# identity as a parameter of internal call, but that could be
+# automatized too (eg by having a special parameter type called "self")
+

 Func - host_get_by_name (void*, smx_host_t) (name, const char*)
 Func - host_get_name (const char*) (host, void*, smx_host_t)
 Proc - host_on (void) (host, void*, smx_host_t)
 Func - host_get_by_name (void*, smx_host_t) (name, const char*)
 Func - host_get_name (const char*) (host, void*, smx_host_t)
 Proc - host_on (void) (host, void*, smx_host_t)