Bug 2044282 - glean-sym: Free data on the other side of FFI#3474
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badboy wants to merge 2 commits into
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Bug 2044282 - glean-sym: Free data on the other side of FFI#3474badboy wants to merge 2 commits into
badboy wants to merge 2 commits into
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I've been testing it with these changes in appservices: mozilla/application-services@main...badboy:application-services:re-enable-glean-sym Basically recording a timing distribution along with the initialization (to make sure it's done early). |
This ensures remote `RustBuffers` are dropped by calling `ffi_glean_core_rustbuffer_free` instead of doing a local drop.
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error log on the old glean-sym: |
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successful run results in a ping like this one. see |
chutten
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r+wc
...needs CHANGELOG? Or I guess it might be covered by the "EXPERIMENTAL" warning
| // SAFETY: | ||
| // * `src` is a newly created `Vec` with `reslen` capacity. | ||
| // * `dst` is a `Vec` pointer with size `reslen` | ||
| // * Both `src` (newly created `Vec`) and `dst` (a pinter obtained from a `Vec`) |
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Suggested change
| // * Both `src` (newly created `Vec`) and `dst` (a pinter obtained from a `Vec`) | |
| // * Both `src` (newly created `Vec`) and `dst` (a pointer obtained from a `Vec`) |
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| let mut newvec = Vec::with_capacity(reslen); | ||
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| // SAFETY: |
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Your safety note might be stale as it references src which doesn't exist.
| // * `ffi_glean_core_rustbuffer_free` is generated by `UniFFI` | ||
| // and accepts the `repr(C)` `RustBuffer` that we previously got via FFI. | ||
| unsafe { | ||
| let mut call_status = uniffi::RustCallStatus::default(); |
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Near as I can tell, default for RustCallStatus isn't unsafe and so it doesn't need to be in here.
| use std::sync::RwLock; | ||
| use std::sync::atomic::{AtomicUsize, Ordering}; | ||
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| macro_rules! elog { |
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I'd like a comment here about the non-allocating logger
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| unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { | ||
| unsafe { |
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| let mut found = false; | ||
| for idx in 0..max_idx { | ||
| let val = map[idx]; | ||
| if val == ptr as usize { | ||
| found = true; | ||
| break; | ||
| } | ||
| } |
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| elog!( | ||
| "%.*s: Trying to dealloc=%p. Pointer wasn't allocated here.", | ||
| self.name.len() as i32, | ||
| self.name.as_ptr(), | ||
| ptr | ||
| ); | ||
| std::process::abort(); |
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elog + abort is different from panic! in what way?
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Unfortunately with the current UniFFI API this will require copying a bit more data.
The first commit adds a test. It will fail.
The second is trying to address it. The test should then succeed.