diff options
| author | Raghavendra K T <raghavendra.kt@amd.com> | 2023-03-01 13:19:03 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-04-06 05:03:03 +0200 |
| commit | d46031f40e0f7f7bf63914bb3f2e404ad3886ecd (patch) | |
| tree | 93792fcd0970660392d9bcbcc8c002ff02f6b7b1 /include | |
| parent | sched/numa: implement access PID reset logic (diff) | |
| download | linux-d46031f40e0f7f7bf63914bb3f2e404ad3886ecd.tar.xz linux-d46031f40e0f7f7bf63914bb3f2e404ad3886ecd.zip | |
sched/numa: use hash_32 to mix up PIDs accessing VMA
before: last 6 bits of PID is used as index to store information about
tasks accessing VMA's.
after: hash_32 is used to take of cases where tasks are created over a
period of time, and thus improve collision probability.
Result:
The patch series overall improves autonuma cost.
Kernbench around more than 5% improvement and system time in mmtest
autonuma showed more than 80% improvement
Link: https://lkml.kernel.org/r/d5a9f75513300caed74e5c8570bba9317b963c2b.1677672277.git.raghavendra.kt@amd.com
Signed-off-by: Raghavendra K T <raghavendra.kt@amd.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Cc: Bharata B Rao <bharata@amd.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Disha Talreja <dishaa.talreja@amd.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mm.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index e05a878e186e..e249208f8fbe 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1691,7 +1691,7 @@ static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) { unsigned int pid_bit; - pid_bit = current->pid % BITS_PER_LONG; + pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG)); if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids[1])) { __set_bit(pid_bit, &vma->numab_state->access_pids[1]); } |