Commit Graph

35 Commits

Author SHA1 Message Date
Damien George
d3f82bc425 py/mpstate.h: Remove obsolete comment about nlr_top being coded in asm. 2017-12-11 22:51:52 +11:00
Damien George
02d830c035 py: Introduce a Python stack for scoped allocation.
This patch introduces the MICROPY_ENABLE_PYSTACK option (disabled by
default) which enables a "Python stack" that allows to allocate and free
memory in a scoped, or Last-In-First-Out (LIFO) way, similar to alloca().

A new memory allocation API is introduced along with this Py-stack.  It
includes both "local" and "nonlocal" LIFO allocation.  Local allocation is
intended to be equivalent to using alloca(), whereby the same function must
free the memory.  Nonlocal allocation is where another function may free
the memory, so long as it's still LIFO.

Follow-up patches will convert all uses of alloca() and VLA to the new
scoped allocation API.  The old behaviour (using alloca()) will still be
available, but when MICROPY_ENABLE_PYSTACK is enabled then alloca() is no
longer required or used.

The benefits of enabling this option are (or will be once subsequent
patches are made to convert alloca()/VLA):
- Toolchains without alloca() can use this feature to obtain correct and
  efficient scoped memory allocation (compared to using the heap instead
  of alloca(), which is slower).
- Even if alloca() is available, enabling the Py-stack gives slightly more
  efficient use of stack space when calling nested Python functions, due to
  the way that compilers implement alloca().
- Enabling the Py-stack with the stackless mode allows for even more
  efficient stack usage, as well as retaining high performance (because the
  heap is no longer used to build and destroy stackless code states).
- With Py-stack and stackless enabled, Python-calling-Python is no longer
  recursive in the C mp_execute_bytecode function.

The micropython.pystack_use() function is included to measure usage of the
Python stack.
2017-12-11 13:49:09 +11:00
Damien George
37282f8fc1 extmod/uos_dupterm: Update uos.dupterm() and helper funcs to have index.
The uos.dupterm() signature and behaviour is updated to reflect the latest
enhancements in the docs.  It has minor backwards incompatibility in that
it no longer accepts zero arguments.

The dupterm_rx helper function is moved from esp8266 to extmod and
generalised to support multiple dupterm slots.

A port can specify multiple slots by defining the MICROPY_PY_OS_DUPTERM
config macro to an integer, being the number of slots it wants to have;
0 means to disable the dupterm feature altogether.

The unix and esp8266 ports are updated to work with the new interface and
are otherwise unchanged with respect to functionality.
2017-10-13 20:01:57 +11:00
Alexander Steffen
55f33240f3 all: Use the name MicroPython consistently in comments
There were several different spellings of MicroPython present in comments,
when there should be only one.
2017-07-31 18:35:40 +10:00
Alexander Steffen
299bc62586 all: Unify header guard usage.
The code conventions suggest using header guards, but do not define how
those should look like and instead point to existing files. However, not
all existing files follow the same scheme, sometimes omitting header guards
altogether, sometimes using non-standard names, making it easy to
accidentally pick a "wrong" example.

This commit ensures that all header files of the MicroPython project (that
were not simply copied from somewhere else) follow the same pattern, that
was already present in the majority of files, especially in the py folder.

The rules are as follows.

Naming convention:
* start with the words MICROPY_INCLUDED
* contain the full path to the file
* replace special characters with _

In addition, there are no empty lines before #ifndef, between #ifndef and
one empty line before #endif. #endif is followed by a comment containing
the name of the guard macro.

py/grammar.h cannot use header guards by design, since it has to be
included multiple times in a single C file. Several other files also do not
need header guards as they are only used internally and guaranteed to be
included only once:
* MICROPY_MPHALPORT_H
* mpconfigboard.h
* mpconfigport.h
* mpthreadport.h
* pin_defs_*.h
* qstrdefs*.h
2017-07-18 11:57:39 +10:00
Damien George
ee86de1f1a py: Make sure that static emg-exc-buffer is aligned to size of mp_obj_t.
This buffer is used to allocate objects temporarily, and such objects
require that their underlying memory be correctly aligned for their data
type.  Aligning for mp_obj_t should be sufficient for emergency exceptions,
but in general the memory buffer should aligned to the maximum alignment of
the machine (eg on a 32-bit machine with mp_obj_t being 4 bytes, a double
may not be correctly aligned).

This patch fixes a bug for certain nan-boxing builds, where mp_obj_t is 8
bytes and must be aligned to 8 bytes (even though the machine is 32 bit).
2017-04-10 16:02:56 +10:00
Damien George
64a4f11b2d py: Remove MP_STATE_CTX, use MP_STATE_THREAD instead (it's an alias).
MP_STATE_CTX was recently aliased to MP_STATE_THREAD and can now be
removed.
2017-03-24 18:43:28 +11:00
Damien George
6e74d24f30 py: Add micropython.schedule() function and associated runtime code. 2017-03-20 15:20:26 +11:00
Damien George
05fe66f68a py: Move locals/globals dicts to the thread-specific state.
Each threads needs to have its own private references to its current
locals/globals dicts, otherwise functions running within different
contexts (eg imported from different files) can behave very strangely.
2017-03-06 17:01:56 +11:00
Damien George
1808b2e8d5 extmod: Remove MICROPY_FSUSERMOUNT and related files.
Replaced by MICROPY_VFS and the VFS sub-system.
2017-01-30 12:26:07 +11:00
Damien George
3f6b4e08e3 extmod/vfs: Expose mp_vfs_mount_t type.
It should only be used for low-level things and with caution, for example
putting mounted VFS data in ROM or the static data section.
2017-01-27 23:22:15 +11:00
Damien George
dcb9ea7215 extmod: Add generic VFS sub-system.
This provides mp_vfs_XXX functions (eg mount, open, listdir) which are
agnostic to the underlying filesystem type, and just require an object with
the relevant filesystem-like methods (eg .mount, .open, .listidr) which can
then be mounted.

These mp_vfs_XXX functions would typically be used by a port to implement
the "uos" module, and mp_vfs_open would be the builtin open function.

This feature is controlled by MICROPY_VFS, disabled by default.
2017-01-27 17:19:06 +11:00
Damien George
7f1da0a03b py: Add MICROPY_KBD_EXCEPTION config option to provide mp_kbd_exception.
Defining and initialising mp_kbd_exception is boiler-plate code and so the
core runtime can provide it, instead of each port needing to do it
themselves.

The exception object is placed in the VM state rather than on the heap.
2016-12-15 13:00:19 +11:00
Paul Sokolovsky
93e353e384 py/gc: Implement GC running by allocation threshold.
Currently, MicroPython runs GC when it could not allocate a block of memory,
which happens when heap is exhausted. However, that policy can't work well
with "inifinity" heaps, e.g. backed by a virtual memory - there will be a
lot of swap thrashing long before VM will be exhausted. Instead, in such
cases "allocation threshold" policy is used: a GC is run after some number of
allocations have been made. Details vary, for example, number or total amount
of allocations can be used, threshold may be self-adjusting based on GC
outcome, etc.

This change implements a simple variant of such policy for MicroPython. Amount
of allocated memory so far is used for threshold, to make it useful to typical
finite-size, and small, heaps as used with MicroPython ports. And such GC policy
is indeed useful for such types of heaps too, as it allows to better control
fragmentation. For example, if a threshold is set to half size of heap, then
for an application which usually makes big number of small allocations, that
will (try to) keep half of heap memory in a nice defragmented state for an
occasional large allocation.

For an application which doesn't exhibit such behavior, there won't be any
visible effects, except for GC running more frequently, which however may
affect performance. To address this, the GC threshold is configurable, and
by default is off so far. It's configured with gc.threshold(amount_in_bytes)
call (can be queries without an argument).
2016-07-21 00:37:30 +03:00
Paul Sokolovsky
426112ce88 extmod/moduos_dupterm: Reserve buffer bytearray object for dupterm.
Allocating it for each read/write operation is a memory fragmentation
hazard.
2016-07-04 13:32:30 +03:00
Damien George
4cec63a9db py: Implement a simple global interpreter lock.
This makes the VM/runtime thread safe, at the cost of not being able to
run code in parallel.
2016-06-28 11:28:50 +01:00
Damien George
1f54ad2aed py: Make interning of qstrs thread safe. 2016-06-28 11:28:50 +01:00
Damien George
c93d9caa8b py/gc: Make memory manager and garbage collector thread safe.
By using a single, global mutex, all memory-related functions (alloc,
free, realloc, collect, etc) are made thread safe.  This means that only
one thread can be in such a function at any one time.
2016-06-28 11:28:49 +01:00
Damien George
27cc07721b py: Add basic _thread module, with ability to start a new thread. 2016-06-28 11:28:48 +01:00
Damien George
330165a2cc py: Add MP_STATE_THREAD to hold state specific to a given thread. 2016-06-28 11:09:31 +01:00
Damien George
ea23520403 py: Add MICROPY_DYNAMIC_COMPILER option to config compiler at runtime.
This new compile-time option allows to make the bytecode compiler
configurable at runtime by setting the fields in the mp_dynamic_compiler
structure.  By using this feature, the compiler can generate bytecode
that targets any MicroPython runtime/VM, regardless of the host and
target compile-time settings.

Options so far that fall under this dynamic setting are:
- maximum number of bits that a small int can hold;
- whether caching of lookups is used in the bytecode;
- whether to use unicode strings or not (lexer behaviour differs, and
  therefore generated string constants differ).
2016-02-25 10:05:46 +00:00
Paul Sokolovsky
72085a669b py/mpstate.h: fs_user_mount is now standard, reusable uPy functionality. 2016-02-15 00:02:03 +02:00
Paul Sokolovsky
00ee84e1e1 py: Clean up instantiation of dupterm object.
To comply with already established scheme for extmod's.
2016-01-01 14:22:57 +02:00
Damien George
257848587f py/qstr: Use size_t instead of mp_uint_t when counting allocated bytes. 2015-12-17 12:41:40 +00:00
Damien George
d977d268e8 py/gc: Use size_t instead of mp_uint_t to count things related to heap.
size_t is the correct type to use to count things related to the size of
the address space.  Using size_t (instead of mp_uint_t) is important for
the efficiency of ports that configure mp_uint_t to larger than the
machine word size.
2015-12-16 20:09:11 -05:00
Paul Sokolovsky
1a1d11fa32 py/modsys: Implement sys.modules.
This for example will allow people to reload modules which didn't load
successfully (e.g. due to syntax error).
2015-12-05 00:13:29 +02:00
Damien George
999cedb90f py: Wrap all obj-ptr conversions in MP_OBJ_TO_PTR/MP_OBJ_FROM_PTR.
This allows the mp_obj_t type to be configured to something other than a
pointer-sized primitive type.

This patch also includes additional changes to allow the code to compile
when sizeof(mp_uint_t) != sizeof(void*), such as using size_t instead of
mp_uint_t, and various casts.
2015-11-29 14:25:35 +00:00
Damien George
94fe6e523d py/gc: Move away from using mp_uint_t, instead use uintptr_t and size_t.
The GC works with concrete pointers and so the types should reflect this.
2015-11-29 14:25:04 +00:00
Damien George
994ff738c8 py/mpstate: Make mp_pending_exception volatile.
It can change asynchronously.
2015-11-17 14:27:21 +00:00
Paul Sokolovsky
e0d7740a22 extmod/modlwip: slip: Use stream protocol and be port-independent.
Based on the original patch by Galen Hazelwood:
https://github.com/micropython/micropython/pull/1517 .
2015-10-27 00:04:59 +03:00
Damien George
ade9a05236 py: Improve allocation policy of qstr data.
Previous to this patch all interned strings lived in their own malloc'd
chunk.  On average this wastes N/2 bytes per interned string, where N is
the number-of-bytes for a quanta of the memory allocator (16 bytes on 32
bit archs).

With this patch interned strings are concatenated into the same malloc'd
chunk when possible.  Such chunks are enlarged inplace when possible,
and shrunk to fit when a new chunk is needed.

RAM savings with this patch are highly varied, but should always show an
improvement (unless only 3 or 4 strings are interned).  New version
typically uses about 70% of previous memory for the qstr data, and can
lead to savings of around 10% of total memory footprint of a running
script.

Costs about 120 bytes code size on Thumb2 archs (depends on how many
calls to gc_realloc are made).
2015-07-14 22:56:32 +01:00
Paul Sokolovsky
8b85d14b92 modsys: Add basic sys.exc_info() implementation.
The implementation is very basic and non-compliant and provided solely for
CPython compatibility. The function itself is bad Python2 heritage, its
usage is discouraged.
2015-04-25 03:49:23 +03:00
Damien George
e1e359ff59 py: Put mp_sys_path, mp_sys_argv and gc_collected in mp_state_ctx_t.
Without mp_sys_path and mp_sys_argv in the root pointer section of the
state, their memory was being incorrectly collected by GC.
2015-02-07 17:24:10 +00:00
Damien George
8b77e3dd2f stmhal: Put mod_network_nic_list in global root-pointer state.
It needs to be scanned by GC.  Thanks to Daniel Campora.
2015-01-22 00:16:41 +00:00
Damien George
b4b10fd350 py: Put all global state together in state structures.
This patch consolidates all global variables in py/ core into one place,
in a global structure.  Root pointers are all located together to make
GC tracing easier and more efficient.
2015-01-07 20:33:00 +00:00