The `JsRuntimeState` struct stores a number of JS callbacks that are
used either in the event loop or when interacting with V8. Some of these
callback fields are vectors of callbacks, and therefore could plausibly
store at least one callback per realm. However, some of those fields are
`Option<v8::Global<v8::Function>>`, which would make the callbacks set
by a realm override the one that might have been set by a different
realm.
As it turns out, all of the current such optional callbacks
(`js_promise_reject_cb`, `js_format_exception_cb` and
`js_wasm_streaming_cb`) are only used from inside a realm, and therefore
this change makes it so such callbacks can only be set from inside a
realm, and will only affect that realm.
This is a reland of #15599.
Towards #13239.
Currently realms are supported on `deno_core`, but there was no support
for async ops anywhere other than the main realm. The main issue is that
the `js_recv_cb` callback, which resolves promises corresponding to
async ops, was only set for the main realm, so async ops in other realms
would never resolve. Furthermore, promise ID's are specific to each
realm, which meant that async ops from other realms would result in a
wrong promise from the main realm being resolved.
This change takes the `ContextState` struct added in #17050, and adds to
it a `js_recv_cb` callback for each realm. Combined with the fact that
that same PR also added a list of known realms to `JsRuntimeState`, and
that #17174 made `OpCtx` instances realm-specific and had them include
an index into that list of known realms, this makes it possible to know
the current realm in the `queue_async_op` and `queue_fast_async_op`
methods, and therefore to send the results of promises for each realm to
that realm, and prevent the ID's from getting mixed up.
Additionally, since promise ID's are no longer unique to the isolate,
having a single set of unrefed ops doesn't work. This change therefore
also moves `unrefed_ops` from `JsRuntimeState` to `ContextState`, and
adds the lengths of the unrefed op sets for all known realms to get the
total number of unrefed ops to compare in the event loop.
This PR is a reland of #14734 after it was reverted in #16366, except
that `ContextState` and `JsRuntimeState::known_realms` were previously
relanded in #17050. Another significant difference with the original PR
is passing around an index into `JsRuntimeState::known_realms` instead
of a `v8::Global<v8::Context>` to identify the realm, because async op
queuing in fast calls cannot call into V8, and therefore cannot have
access to V8 globals. This also simplified the implementation of
`resolve_async_ops`.
Co-authored-by: Luis Malheiro <luismalheiro@gmail.com>
This commit changes implementation of "Deno.memoryUsage()" to return
correct value for "rss" field. To do that we implement a specialized function
per os to retrieve this information.
Currently runtime exception are only displayed at the program end in
terminal, which makes it only a partial fix, as a full fix requires
https://github.com/denoland/rusty_v8/pull/1149 which adds new bindings
to the inspector that allows to notify it about thrown exceptions.
This will be handled in a follow up commit.
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time 188 ms rate 53191
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This revert has been discussed at length out-of-band (including with
@andreubotella). The realms work in impeding ongoing event loop and
performance work. We very much want to land realms but it needs to wait
until these lower-level refactors are complete. We hope to bring realms
back in a couple weeks.
The `JsRuntimeState` struct stores a number of JS callbacks that are
used either in the event loop or when interacting with V8. Some of
these callback fields are vectors of callbacks, and therefore could
plausibly store at least one callback per realm. However, some of
those fields are `Option<v8::Global<v8::Function>>`, which would make
the callbacks set by a realm override the one that might have been set
by a different realm.
As it turns out, all of the current such optional callbacks
(`js_promise_reject_cb`, `js_format_exception_cb` and
`js_wasm_streaming_cb`) are only used from inside a realm, and
therefore this change makes it so such callbacks can only be set from
inside a realm, and will only affect that realm.
Pull request #14019 enabled initial support for realms, but it did not
include support for async ops anywhere other than the main realm. The
main issue was that the `js_recv_cb` callback, which resolves promises
corresponding to async ops, was only set for the main realm, so async
ops in other realms would never resolve. Furthermore, promise ID's are
specific to each realm, which meant that async ops from other realms
would result in a wrong promise from the main realm being resolved.
This change creates a `ContextState` struct, similar to
`JsRuntimeState` but stored in a slot of each `v8::Context`, which
contains a `js_recv_cb` callback for each realm. Combined with a new
list of known realms, which stores them as `v8::Weak<v8::Context>`,
and a change in the `#[op]` macro to pass the current context to
`queue_async_op`, this makes it possible to send the results of
promises for different realms to their realm, and prevent the ID's
from getting mixed up.
Additionally, since promise ID's are no longer unique to the isolate,
having a single set of unrefed ops doesn't work. This change therefore
also moves `unrefed_ops` from `JsRuntimeState` to `ContextState`, and
adds the lengths of the unrefed op sets for all known realms to get
the total number of unrefed ops to compare in the event loop.
Co-authored-by: Luis Malheiro <luismalheiro@gmail.com>
Relanding #12994
This commit adds support for "unhandledrejection" event.
This event will trigger event listeners registered using:
"globalThis.addEventListener("unhandledrejection")
"globalThis.onunhandledrejection"
This is done by registering a default handler using
"Deno.core.setPromiseRejectCallback" that allows to
handle rejected promises in JavaScript instead of Rust.
This commit will make it possible to polyfill
"process.on("unhandledRejection")" in the Node compat
layer.
Co-authored-by: Colin Ihrig <cjihrig@gmail.com>
The `op_event_loop_has_more_work` op, introduced in #14830, duplicates
code from `JsRuntime::poll_event_loop`. That PR also added the unused
method `JsRuntime::event_loop_has_work`, which is another duplication
of that same code, and which isn't used anywhere.
This change deduplicates this by renaming
`JsRuntime::event_loop_has_work` to `event_loop_pending_state`, and
making it the single place to determine what in the event loop is
pending. This result is then returned in a struct which is used both
in the event loop and in the `op_event_loop_has_more_work` op.
This commit adds support for "unhandledrejection" event.
This event will trigger event listeners registered using:
"globalThis.addEventListener("unhandledrejection")
"globalThis.onunhandledrejection"
This is done by registering a default handler using
"Deno.core.setPromiseRejectCallback" that allows to
handle rejected promises in JavaScript instead of Rust.
This commit will make it possible to polyfill
"process.on("unhandledRejection")" in the Node compat
layer.
Co-authored-by: Colin Ihrig <cjihrig@gmail.com>
Keep a cache for source maps and source lines.
We sort of already had a cache argument for source map lookup
functions but we just passed an empty map instead of storing it.
Extended it to cache source line lookups as well and plugged it
into runtime state.
