> Prior to this patch, the `StackYellowPages` and `StackRedPages` > influenced the total reserved stack memory, but they didn't change the > minimum stack size specified as required by HotSpot to Windows. This > patch adds the call to `SetThreadStackGuarantee()` to set the minimum > stack size. > > The key change here is that the argument to `SetThreadStackGuarantee()` > is set to one less than the total number of yellow pages. The one less > page is because Windows uses a guard page (access to which tells Windows > to commit more stack pages); in the terminal case, we want the guard > page to coincide with the top-most yellow stack page, thus leaving all > except one yellow page available as the stack size. > > Importantly, however, we do not use the red page count as the argument > to `SetThreadStackGurantee()`, since the red stack pages are unavailable > for handling recoverable overflows. The red page count impacts the > _total reserved_ stack size, just not the _minimum_ stack size. Still, > forcing the red stack page count to be included into the computation of > the argument to `SetThreadStackGurantee()` causes HotSpot to fail with > the assertion `assert(!in_vm) failed: Undersized StackShadowPages`, > since Windows is unable to commit more stack pages due to the minimum > stack size now being larger than just the yellow page count minus one. > > The accompanying test passes zero to `SetThreadStackGuarantee()` to > probe the current minimum stack size, which we then compare against the > expected size based on the yellow page count. The same test fails > without this patch on both Windows/x64 and on Windows/ARM64. > > Validated this patch by running through all tier 1, 2, and 3 HotSpot > jtreg tests on Windows/x64 and Windows/ARM64 in FastDebug config. > > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai).
Ashay Rane has updated the pull request incrementally with one additional commit since the last revision: Update comment block to be precise about `SetThreadStackGuarantee()` ------------- Changes: - all: https://git.openjdk.org/jdk/pull/32365/files - new: https://git.openjdk.org/jdk/pull/32365/files/fc2041f3..75a0036c Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=32365&range=02 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=32365&range=01-02 Stats: 11 lines in 1 file changed: 1 ins; 1 del; 9 mod Patch: https://git.openjdk.org/jdk/pull/32365.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/32365/head:pull/32365 PR: https://git.openjdk.org/jdk/pull/32365
