X-Git-Url: http://bilbo.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/cd69f8c66886ae218c6a9b38125b27fe157e6bb2..bfffef69e1b0554d13eec920f1a32f75b49ceac6:/doc/doxygen/inside_extending.doc diff --git a/doc/doxygen/inside_extending.doc b/doc/doxygen/inside_extending.doc index 0f4e1c6c36..dfd7e5784a 100644 --- a/doc/doxygen/inside_extending.doc +++ b/doc/doxygen/inside_extending.doc @@ -1,184 +1,85 @@ -/*! -\page inside_extending Extending SimGrid - -\tableofcontents - -\section simgrid_dev_guide_model How to add a new model in surf? -The figure below show the architecture of the SURF layer. This layer is composed -of different kind of models representing the differents systems we want to -modelize (i.e.cpu, network, storage, workstation, virtual machine). - -A model in simgrid is composed of three classes: Model, Resource and Action -(surf_interface.hpp). - -\image html surf++.png -\image latex surf++.pdf "surf++" width=\textwidth - -Actually there are five kind of models: CpuModel, NetworkModel, WorkstationModel, -WorkstationVMModel and StorageModel. For each kind of model, there is an -interface (e.g.: cpu_interface.hpp) and some implementations (e.g.: cpu_cas01.hpp, -cpu_ti.hpp). - -init function: -void surf_cpu_model_init_Cas01() -s_surf_model_description_t surf_network_model_description[] = { - -\subsection simgrid_dev_guide_model_implem How to add a new model implementation in surf? - -If you want to create a new implementation of a kind of model you must extend -the classes of the corresponding interfaces. - -For instance, if you want to add a new cup model called `Plop`, create two files -cpu_plop.hpp and cpu_plop_cpp which contains classes CpuPlopModel, CpuPlop and -CpuPlopAction implementating respectively the interfaces CpuModel, Cpu and -CpuAction. You also need to define a initializing function like this: - -~~~~ -void surf_cpu_model_init_plop() -{ - xbt_assert(!surf_cpu_model_pm); - - surf_cpu_model_pm = new CpuPlopModel(); - - sg_platf_host_add_cb(cpu_parse_init); - sg_platf_postparse_add_cb(cpu_add_traces); - - xbt_dynar_push(model_list, &surf_cpu_model_pm); +/** +@page inside_extending Extending SimGrid + +@tableofcontents + +@section simgrid_dev_guide_generic_simcall The modern SimCall interface + +We now have some generic simcalls which can be used to interface with the +Maestro without creating new simcalls. You might want to use them instead of +the defining additional simcalls. The long term goal is to replace most of +the simcalls with the generic ones. + +For simcalls which never block, `kernelImmediate()` can be used. It takes a +C++ callback executes it in maestro. Any value returned by the callback is +returned by `kernelImmediate()`. Conversely, if the callback throws an +exception, this exception is propagated out of `kernelImmediate()`. Executing +the code in maestro enforces mutual exclusion (no other user process is running) +and enforce a deterministic order which guarantees the reproducibility of the +simulation. This call is particularly useful for implementing mutable calls: + +~~~ +void Host::setProperty(const char*key, const char *value){ + simgrid::simix::kernelImmediate([&] { + simgrid::kernel::resource::HostImpl* host = + this->extension(); + host->setProperty(key,value); + }); } -~~~~ - -and add an entry in the corresponding array in surf_interface.cpp - -~~~~ -s_surf_model_description_t surf_cpu_model_description[] = { - {"Cas01", - "Simplistic CPU model (time=size/power).", - surf_cpu_model_init_Cas01}, - {"Plop", - "The new plop CPU model.", - surf_cpu_model_init_plop}, - {NULL, NULL, NULL} // this array must be NULL terminated -}; -~~~~ - -\subsection simgrid_dev_guide_model_kind How to add a new kind of model in surf? - -If you want to create a new kind of model, you must create a new interface -where you extend the classes Model, Resource and Action, and then create an -implementation of this interface. - - -\section simgrid_dev_guide_surf_callbacks How to use surf callbacks? - -Adding features to surf could also be handle by using surf callbacks (instead -of adding new implementation model). The list of available callbacks is -accessible there \ref SURF_callbacks. An example of using surf callbacks is the -energy plugin. If you want to add a plugin you need to define callback function -and to connect them to callbacks handler in an initialization function. - -~~~~ -static void MyNetworkLinkCreatedCallback(NetworkLinkPtr cpu){ - // your code -} - -static void MyNetworkLinkDestructedCallback(NetworkLinkPtr cpu){ - // your code -} - -static void MyNetworkCommunicationCallback(NetworkActionPtr cpu, - RoutingEdgePtr src, - RoutingEdgePtr dst){ - // your code +~~~ + +If there is no blocking and no mutation involved (getters), you might consider +avoiding switching to Maestro and reading directly the data you're interested +in. + +For simcalls which might block, `kernel_sync()` can be used. It takes a +C++ callback and executes it immediately in maestro. This C++ callback is +expected to return a `simgrid::kernel::Future` reprensenting the operation +in the kernel. When the operations completes, the user process is waken up +with the result: + +~~~ +try { + std::vector result = simgrid::simix::kernel_sync([&] { + // Fictional example, simgrid::kernel::readFile does not exist. + simgrid::kernel::Future> result = simgrid::kernel::readFile(file); + return result; + }); + XBT_DEBUG("Finished reading file %s: length %zu", file, result.size()); } - -void sg_my_network_plugin_init() { - surf_callback_connect(networkLinkCreatedCallbacks, - MyNetworkLinkCreatedCallback); - surf_callback_connect(networkLinkDestructedCallbacks, - MyNetworkLinkDestructedCallback); - surf_callback_connect(networkCommunicationCallbacks, - MyNetworkCommunicationCallback); +// If the operation failed, kernel_sync() throws an exception: +catch (std::runtime_error& e) { + XBT_ERROR("Could not read file %s", file); } -~~~~ +~~~ -Then you need to add an entry in surf_interface.cpp refering to your -initialization function. +Asynchronous blocks can be implemented with `kernel_async()`. It works +like `kernel_sync()` but does not block. Instead, it returns a +`simgrid::simix::Future` representing the operation in the process: -~~~~ -s_surf_model_description_t surf_plugin_description[] = { - {"Energy", - "Cpu energy consumption.", - sg_energy_plugin_init}, - {"MyNetworkPlugin", - "My network plugin.", - sg_my_network_plugin_init}, - {NULL, NULL, NULL} // this array must be NULL terminated +~~~ +simgrid::simix::Future> result = simgrid::simix::kernel_sync([&] { + // Fictional example, simgrid::kernel::readFile does not exist. + simgrid::kernek::Future> result = simgrid::kernel::readFile(file); + return result; }; -~~~~ - -\section simgrid_dev_guide_simcall How to add a new simcall? -A simcall is used to go from user mode to kernel mode. The workflow of -a simcall is the following: - -- ` simcall_()` - - `simcall_BODY_()` - - create the simcall - - `SIMIX_process_yield` if not maestro - - ========== KERNEL MODE ========== - - `SIMIX_simcall_pre` - - `SIMIX_pre_(simcall, )` - - `SIMIX_simcall_answer(simcall)` -To simplify the simcall creation, we have made a python script that -generate most of the code and give helpers for the remaining stuff. -The script generating the simcalls (src/simix/simcalls.in) take in input -the src/simix/simcalls.in file where the simcalls are defined and generate -the following files: +// Do some work while the operation is pending: +while (!result.is_ready() && hasWorkToDo()) + doMoreWork(); -- simcall_generated_args_getter_setter.h: - functions to get and set simcall arguments -- simcall_generated_res_getter_setter.h: - functions to get and set simcall result -- simcall_generated_body.c: - the BODY function of the simcall -- simcall_generated_case.c: - the case of the SIMIX_simcall_pre function -- simcall_generated_enum.h: - the enum of simcalls -- simcall_generated_string.c: - string corresponding to the enum to debug - -Furthermode if the simcall_ or the SIMIX_pre_ function are missing, -a warning will show up with a prototype of the corresponding fonction to fill. - -The simcall.in file list all the simcalls in sections. A line starting by "##" -define a new section which will be replace by a "ifdef" in the generated code. -There is a simcall by line which follow this format: +// We don't have anything to do, wait for the operation to complete and +// get its value: +try { + std:vector data = result.get(); + XBT_DEBUG("Finished reading file %s: length %zu", file, data.size()); +} +// If the operation failed, .get() throws an exception: +catch (std::runtime_error& e) { + XBT_ERROR("Could not read file %s", file); +} +~~~ -~~~~ -Simcall -> Name HasAnswer Res Args -Name -> [a-z0-9_]+ -Has_Answer -> "True" | "False" -Res -> "(" Type MaybeCast ")" -Args -> Args Arg | Arg -Arg -> "(" Name "," Type MaybeCast ")" -Type -> "char" | "const char*" | "int" | "long" | "unsigned char" | "unsigned short" | "unsigned int" | "unsigned long" | "float" | "double" | "void*" | "FPtr" | "const void*" | "size_t" | "sg_size_t" | "void" | "void*" -MaybeCast -> "," Cast | "" -Cast -> [a-z0-9_* ]+ -~~~~ +Note: `kernel_sync(f)` could be implemented as `kernel_async(f).get()`. -\section simgrid_dev_guide_tag What is How to add a new tag for xml files? -Search for expression \"TUTORIAL: New TAG\". -\verbatim -user@caraja:~/workspace/simgrid/src$ cg "TUTORIAL: New TAG" -0 surf/sg_platf.c 43 /* TUTORIAL: New TAG*/ -1 surf/sg_platf.c 89 /* TUTORIAL: New TAG*/ -2 surf/sg_platf.c 124 /* TUTORIAL: New TAG*/ -3 surf/sg_platf.c 337 /* TUTORIAL: New TAG*/ -4 surf/surfxml_parse.c 769 /* TUTORIAL: New TAG*/ -5 surf/surf_private.h 205 /* TUTORIAL: New TAG*/ -6 surf/surfxml_parseplatf.c 64 /* TUTORIAL: New TAG*/ -7 surf/surfxml_parseplatf.c 85 /* TUTORIAL: New TAG*/ -8 include/simgrid/platf_interface.h 42 /* TUTORIAL: New TAG*/ -\endverbatim */