| Message ID | 20250118-vfs-kcore-913a66eabd03@brauner (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [GIT,PULL] vfs kcore | expand |
The pull request you sent on Sat, 18 Jan 2025 13:56:55 +0100:
> git@gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.14-rc1.kcore
has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/d5829524243652409e3fa2853736649674c294f0
Thank you!
Hey Linus, /* Summary */ The performance of /proc/kcore reads has been showing up as a bottleneck for the drgn debugger. drgn scripts often spend ~25% of their time in the kernel reading from /proc/kcore. A lot of this overhead comes from silly inefficiencies. This pull request contains fixes for the low-hanging fruit. The fixes are all fairly small and straightforward. The result is a 25% improvement in read latency in micro-benchmarks (from ~235 nanoseconds to ~175) and a 15% improvement in execution time for real-world drgn scripts: - Make /proc/kcore entry permanent. - Avoid walking the list on every read. - Use percpu_rw_semaphore for kclist_lock. - Make Omar Sandoval the official maintainer for /proc/kcore. /* Testing */ gcc version 14.2.0 (Debian 14.2.0-6) Debian clang version 16.0.6 (27+b1) No build failures or warnings were observed. /* Conflicts */ Merge conflicts with mainline ============================= No known conflicts. Merge conflicts with other trees ================================ No known conflicts. The following changes since commit 40384c840ea1944d7c5a392e8975ed088ecf0b37: Linux 6.13-rc1 (2024-12-01 14:28:56 -0800) are available in the Git repository at: git@gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.14-rc1.kcore for you to fetch changes up to 4972226d0dc48ddedf071355ca664fbf34b509c8: Merge patch series "proc/kcore: performance optimizations" (2024-12-02 11:21:07 +0100) Please consider pulling these changes from the signed vfs-6.14-rc1.kcore tag. Thanks! Christian ---------------------------------------------------------------- vfs-6.14-rc1.kcore ---------------------------------------------------------------- Christian Brauner (1): Merge patch series "proc/kcore: performance optimizations" Omar Sandoval (4): proc/kcore: mark proc entry as permanent proc/kcore: don't walk list on every read proc/kcore: use percpu_rw_semaphore for kclist_lock MAINTAINERS: add me as /proc/kcore maintainer MAINTAINERS | 7 +++++ fs/proc/kcore.c | 81 +++++++++++++++++++++++++++++---------------------------- 2 files changed, 48 insertions(+), 40 deletions(-)