Protect vmstats on PREEMPT_RT
Status from this message: [merged] mm-vmstat-protect-per-cpu-variables-with-preempt-disable-on-rt.patch removed from -mm tree
Get series with b4
b4 am [email protected]Versions newest first · linked by author and title
- v2 Latest1 patch 8 repliesApplied 1/1
- v12 patches 8 repliesSuperseded
Changes in v2 from the cover letter
o Remove preempt_[en|dis]able_rt helper
Patches in v2 All 1 applied
| # | Subject and files | Size | Replies | Applied |
|---|---|---|---|---|
| 1/1 | mm/vmstat: Protect per cpu variables with preempt disable on RTmm/ | +48 | 8 replies | Applied |
Reviews trailers per patch
The patch has a Reviewed-by or Acked-by.
| Patch | Vlastimil Babka |
|---|---|
| 1/1 | A-b |
Trailers given in replies are filled; those carried in the patches from earlier versions are outlined with dashes.
Cover letter [PATCH 0/1 v2] Protect vmstats on PREEMPT_RT
Changelog since v1
o Remove preempt_[en|dis]able_rt helper
When adding local_lock support to mm/page_alloc.c and reducing the overhead of vmstats in general, I wondered how vmstats could be safe on PREEMPT_RT as it partially relies on interrupts being disabled for the stats that must be accurate for correctness. As it turns out, the preempt-rt tree already encountered the same problem.
This series protects just the accurate counters. As Thomas expressed concern that the preempt_enable_rt() helper could be abused, this version open-codes the preemption with a comment explaining why it is necessary.
This is specific to PREEMPT_RT which cannot be enabled on mainline yet and should have no impact on !PREEMPT_RT kernels.
This patch replaces the following mmotm patches
o preempt-provide-preempt__nort-variants.patch
o mm-vmstat-protect-per-cpu-variables-with-preempt-disable-on-rt.patch
Signature · 1 line
2.31.1