With the listener filter from the previous commit, the wake hook only fires
on actual OTA connection attempts — no more spurious wakes from API client
data packets or other monitored-socket traffic. That removes the motivation
for inlining the hook at three call sites.
Collapse back to the simpler shape:
- Application gains Component *ota_wake_component_ (one pointer, 4 bytes,
gated on USE_OTA) and a wake_ota_component_any_context() inline method.
- lwip_fast_select.c reaches the method via an extern-C trampoline
(esphome_wake_ota_component_any_context) defined in application.cpp.
One call_n instruction per actual wake, which now happens at most once
per real OTA upload attempt.
- Raw-TCP (LWIPRawListenImpl::accept_fn_) and host select paths call
App.wake_ota_component_any_context() directly — both are .cpp files.
- wake.h reverts to its pre-PR state (no C-compatible section, no extern
pointer globals, no inline OTA hook). All wake-related state still lives
in Application.
Net effect versus the inline approach:
- RAM: -4 bytes (one pointer vs two)
- Flash: ~-60 bytes (no 3x duplication of the inlined hook body)
- CPU: function-call overhead (~10 cycles) paid only on actual OTA wakes,
which happen ~0 times/sec in steady state. Inline was premature once
filtering reduced the fire rate to "rare intentional events."
get_cached_sock() was a new public method that only OTA's fast-select wake
filter would ever call. Drop it. The existing public C API already covers
this: esphome_lwip_get_sock(fd) looks up a lwip_sock* from a file descriptor
(it's exactly what BSDSocketImpl's own constructor calls to populate
cached_sock_). OTA uses the public get_fd() + esphome_lwip_get_sock() chain
instead — no new Socket accessor, no friend declarations, no layering
concerns. The one-time lookup at setup is negligible.
The inline OTA wake hook was firing on every NETCONN_EVT_RCVPLUS across every
monitored socket (API client data packets, mDNS queries, web server, etc.).
Each false fire paid two volatile stores + memw barriers to mark OTA
pending-enable, only for OTA::loop() to run a wake-up tick and re-disable
itself because there was no actual listener activity.
Add a compare-against-listener filter in esphome_socket_event_callback so the
wake hook only fires when `conn` matches the OTA listen socket's netconn.
Non-match sockets now cost only a pointer load + one branch (~3 instructions)
instead of the full ~10-instruction hook body.
Plumbing:
- lwip_fast_select.[ch]: new s_ota_listener_conn global +
esphome_fast_select_set_ota_listener_sock() setter, used in the callback.
- BSDSocketImpl / LwIPSocketImpl: new public get_cached_sock() accessor (only
under USE_LWIP_FAST_SELECT) mirroring the existing get_fd() pattern.
- ESPHomeOTAComponent::setup(): after registering the wake component,
install the listener filter with this->server_->get_cached_sock().
Raw TCP (ESP8266/RP2040) is unaffected — that path wakes from
LWIPRawListenImpl::accept_fn_, which only fires for the specific listener
pcb it was registered on, so the filtering is implicit there.
All wake_* state lives in one place now. wake.h gains a C-compatible section
at the top (the inline esphome_wake_ota_component_any_context() + its two
extern 'volatile bool *' globals) guarded outside any C++ namespace, with
the existing C++ platform wake primitives moved behind an outer
#ifdef __cplusplus. lwip_fast_select.c includes wake.h directly for the
inline; .cpp files continue to see the C++ side as before.
Deletes the ephemeral esphome/core/ota_wake_hook.h — same code, better home.
The extern C shim esphome_wake_ota_component_any_context() was an out-of-line
call from lwip_fast_select.c into application.cpp: save registers, call,
prologue, two stores, epilogue, ret. Per-RCVPLUS, that's ~10-15 Xtensa cycles
of pure call overhead on top of the two volatile bool stores the shim actually
does.
Move the body into a new C-compatible header (esphome/core/ota_wake_hook.h)
as a static inline, backed by two extern C 'volatile bool *' globals that
point at Component::pending_enable_loop_ and
Application::has_pending_enable_loop_requests_. set_ota_wake_component()
captures the addresses once at registration time; the fast-select callback
then inlines a null-check + two volatile stores with zero call overhead.
The main loop sees the same two flags it already checks every iteration
(has_pending_enable_loop_requests_ gates enable_pending_loops_, which
iterates the inactive section looking for components with
pending_enable_loop_ set). Zero new main-loop work — the inline hook writes
exactly the state enable_loop_soon_any_context() would have written.
RAM change: -4 bytes on Application (ota_wake_component_ field removed) plus
+8 bytes in BSS for the two extern pointers. Net +4 bytes RAM.
Raw-TCP and HOST paths switched from App.wake_ota_component_any_context() to
the inline hook too.
Emitting -DUSE_OTA alongside the defines.h #define USE_OTA entry caused
'USE_OTA redefined' warnings in every TU that includes defines.h. Use a
distinct ESPHOME_USE_OTA name for the compiler -D flag — only the .c
files that cannot include defines.h (lwip_fast_select.c) reference the
ESPHOME_-prefixed name, and everyone else continues to use USE_OTA via
defines.h.
Root cause of the wake failure: ota/__init__.py only called
cg.add_define("USE_OTA"), which writes to the generated defines.h. That's
invisible to .c translation units that can't include defines.h — notably
lwip_fast_select.c, which can't include defines.h because macros.h →
Arduino.h under Arduino builds would break the C compile.
So the #ifdef USE_OTA gate inside lwip_fast_select.c's RCVPLUS callback
was always false, and esphome_wake_ota_component_any_context() was never
called. The listener callback fired (total rcvplus counter incremented
from the device), but OTA's pending-enable flag was never set, so the
main task woke and ran a loop iteration without touching the (disabled)
OTA component.
Fix: emit both cg.add_define (keeps defines.h in sync for static
analyzers / IDEs) and cg.add_build_flag("-DUSE_OTA") (passes it as a
compiler -D flag, visible to every .c TU). Also reverts all the
diagnostic scaffolding (per-loop-tick logs, debug counters, runtime
function pointer hook) that I added while chasing this.
The wake-hook call (esphome_wake_ota_component_any_context / App.wake_ota_component_any_context)
was placed AFTER xTaskNotifyGive()/wake_loop_any_context() in both the fast-select callback and
the raw-TCP accept callback. That opened a race: the main task could wake, run a full iteration
(draining has_pending_enable_loop_requests_), and finish before the flag-set ran — losing the
pending-enable request until the next unrelated socket event happened to re-trigger the path.
Swap the order so the pending-enable flags are set first, then the main task is woken. The
main-loop iteration triggered by the wake is now guaranteed to see the pending request.
Note: host's yield_with_select_ path already sets and consumes the flag on the main thread
with no cross-task wake in between, so it has no race and is unchanged.
The wake hook is called only from:
- esphome_socket_event_callback (lwip fast select, LwIP TCP/IP task context)
- LWIPRawListenImpl::accept_fn_ (raw TCP accept callback)
- Application::yield_with_select_ (host select fallback, main thread)
None of those contexts require IRAM-resident code. The LwIP fast-select
event callback itself is not IRAM_ATTR; the raw-TCP accept callback runs
from a low-priority user IRQ on RP2040 where IRAM_ATTR is a no-op anyway
(it's an ESP32-specific section attribute for code that must run while
flash cache is disabled). This is not a real ISR path the way
enable_loop_soon_any_context() is (which is called from GPIO ISRs and
genuinely does need IRAM).
Removing IRAM_ATTR frees scarce IRAM on ESP32.
Addresses copilot review on #15636.
1. Fix cleanup_connection_() race with queued listener events.
While an OTA session was active, a second incoming connection would
fire esphome_socket_event_callback → esphome_wake_ota_component_any_context,
which sets pending_enable_loop_ on the (still-active) OTA component.
enable_pending_loops_() only scans the inactive section, so that flag
goes invisible. When cleanup_connection_() then called disable_loop(),
the component dropped to LOOP_DONE with a stale pending flag and
nothing to re-trigger the scan — the queued client sat forever until
some unrelated socket activity woke the main loop.
Fix: don't call disable_loop() from cleanup_connection_(). loop() has
the idempotent idle check at its top; one more dispatch after cleanup
is cheap and guarantees we re-read server_->ready() and either accept
the queued client or disable cleanly.
2. Tighten the multi-port error message. Merging is fine — the constraint
is single-port. Reworded: "Only a single port is supported for 'ota'
'platform: esphome'. Got ports [...]. Consolidate onto a single port;
configs sharing a port are merged automatically."
3. Comment drift: three call sites and the fast-select extern declaration
still referred to enable_loop_soon_any_context() and implied the hook
wakes the main loop. Updated to reflect the current mechanism (sets
pending-enable flags only; callers have already woken the main loop).
Also clarified that esphome_wake_ota_component_any_context fires on
every RCVPLUS event across all monitored sockets, so false wakes are
expected and OTA::loop() disables itself again when idle.
4. Added tests/component_tests/ota/test_esphome_ota.py covering
ota_esphome_final_validate: single instance accepted, same-port
configs merge, different-port configs rejected with cv.Invalid,
non-esphome platforms unaffected.
Address copilot review on #15636.
1. Enforce single ESPHome OTA instance (BREAKING CHANGE).
The `ota_esphome_final_validate` hook has always merged multiple
`ota: - platform: esphome` configs by port so a user config and a
remote package that both define OTA would merge rather than break.
That merge behavior is preserved. But if two configs survive on
*different* ports they produce two independent listening sockets,
which is not a sane deployment: it creates ambiguity for safe_mode
coordination and for the socket wake hook added in this PR.
Raise cv.Invalid when more than one port remains after merging.
2. Drop redundant main-loop wake in Application::wake_ota_component_any_context.
Every caller (lwip fast-select callback already calls xTaskNotifyGive,
raw-tcp accept callback already calls wake_loop_any_context(), host
path is already running post-select in the main loop) has woken the
main loop by the time we reach this hook. Calling
enable_loop_soon_any_context() would re-wake it. Application is a
friend of Component, so set pending_enable_loop_ and
has_pending_enable_loop_requests_ directly instead.
ESPHomeOTAComponent::loop() previously ran every main-loop tick just to
check `client_ != nullptr || server_->ready()` — a wasted dispatch on
every device, since OTA is idle the vast majority of the time.
OTA now disables its own loop after setup() and after cleanup_connection_().
A single 4-byte Component* slot in Application (only compiled in under
USE_OTA) lets the existing socket-wake paths call
enable_loop_soon_any_context() on the registered OTA component:
- ESP32 / LibreTiny (lwip fast select): hooked in
esphome_socket_event_callback on NETCONN_EVT_RCVPLUS.
- ESP8266 / RP2040 (raw TCP): hooked in LWIPRawListenImpl::accept_fn_
right after the existing wake_loop_any_context() call.
- Host (select fallback): called after select() returns ready in
Application::yield_with_select_.
False wakes (e.g. an API-socket event firing the fast-select callback)
land in ESPHomeOTAComponent::loop(), which re-disables itself immediately
when idle. Net cost is still far below running every tick.
This is deliberately an OTA-only hook: OTA is the only component that
benefits, and a single global slot avoids adding per-socket Component*
storage, wake-callback lists, or any new API churn to the socket layer.
J. Nick Koston