After replacing PAI vtable dispatch with direct calls in the previous
commit, the embedded pai_t member in pac_t and hpa_shard_t is dead
weight, and pai.h has no remaining users. Remove them.
Changes:
- Drop pai_t pai member (and "must be first member" comment) from
pac_t and hpa_shard_t.
- Replace #include "jemalloc/internal/pai.h" with the actually-needed
edata.h / tsd_types.h in pac.h, hpa.h, sec.h, pa.h.
- Update extent_pai_t comment in edata.h to no longer reference pai.h.
- Update three remaining test files (hpa_thp_always,
hpa_vectorized_madvise, hpa_vectorized_madvise_large_batch) to call
hpa_*(tsdn, shard, ...) directly instead of pai_*(tsdn, &shard->pai,
...).
- Delete include/jemalloc/internal/pai.h.
No behavioral changes.
The pai_t interface implements C-style polymorphism via function pointers
to abstract over PAC and HPA. This abstraction provides no real benefit:
only two implementations exist, the dispatcher already knows which one to
use, and HPA stubs 2 of 5 operations. Remove the runtime dispatch in
favor of direct calls.
This commit:
- Promotes pac_alloc/expand/shrink/dalloc/time_until_deferred_work to
external linkage and replaces the pai_t *self parameter with pac_t *pac.
- Promotes hpa_alloc/expand/shrink/dalloc/time_until_deferred_work to
external linkage and replaces pai_t *self with hpa_shard_t *shard.
- Updates hpa_dalloc_batch's signature to take hpa_shard_t * directly
and removes the hpa_from_pai container-of helper. Updates internal
callers in hpa_alloc, hpa_dalloc, and hpa_sec_flush_impl.
- Drops the vtable assignments from pac_init() and hpa_shard_init().
- Replaces pai_alloc/dalloc/etc. dispatch in pa.c with direct calls.
HPA expand and shrink (which are unconditional failure stubs) are
skipped entirely for HPA-owned extents.
- Removes the pa_get_pai() helper.
- Updates tests in test/unit/hpa.c and test/unit/hpa_sec_integration.c
to call hpa_alloc/dalloc/etc. directly.
The pai_t struct field stays as dead weight in pac_t and hpa_shard_t;
it is removed in the next commit along with pai.h itself.
No behavioral changes.
Some pages (e.g., hugetlb pages) cannot be purged, and should be
prioritized for reuse. A custom extent_alloc hook signals this by
OR'ing EXTENT_ALLOC_FLAG_PINNED into the low bits of the returned
pointer; jemalloc strips the flag bits and caches pinned extents in
a dedicated ecache_pinned, separate from the dirty/muzzy decay
pipeline.
Pinned extents do not coalesce eagerly, except for ones larger than
SC_LARGE_MINCLASS. A prefer-small policy reuses the smallest fitting
pinned extent, to avoid unnecessary split/fragmentation.
Header files are now self-contained, which makes the relationships
between the files clearer, and crucially allows LSP tools like `clangd`
to function correctly in all of our header files. I have verified that
the headers are self-contained (aside from the various Windows shims) by
compiling them as if they were C files – in a follow-up commit I plan to
add this to CI to ensure we don't regress on this front.
This was promised in the review of the introduction of geom_grow, but would have
been painful to do there because of the series that introduced it. Now that
those are comitted, renaming is easier.
For now, this is just a stub containing the ecaches, with no surrounding code
changed. Eventually all the core allocator bits will be moved in, in the
subsequent stack of commits.
guangli-dai