912090bcce
MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/4114 JIRA: https://issues.redhat.com/browse/RHEL-15602 This is a set of simple backports for the following upstream series plus its follow-up fixes: " Patch series "/msg: mitigate the lock contention in ipc/msg", v6. Here are two patches to mitigate the lock contention in ipc/msg. The 1st patch is to add the new interface percpu_counter_add_local and percpu_counter_sub_local. The batch size in percpu_counter_add_batch should be very large in heavy writing and rare reading case. Add the "_local" version, and mostly it will do local adding, reduce the global updating and mitigate lock contention in writing. The 2nd patch is to use percpu_counter instead of atomic update in ipc/msg. The msg_bytes and msg_hdrs atomic counters are frequently updated when IPC msg queue is in heavy use, causing heavy cache bounce and overhead. Change them to percpu_counter greatly improve the performance. Since there is one percpu struct per namespace, additional memory cost is minimal. Reading of the count done in msgctl call, which is infrequent. So the need to sum up the counts in each CPU is infrequent. Link: https://lkml.kernel.org/r/20220913192538.3023708-1-jiebin.sun@intel.com " Signed-off-by: Rafael Aquini <aquini@redhat.com> Approved-by: Waiman Long <longman@redhat.com> Approved-by: Nico Pache <npache@redhat.com> Approved-by: Chris von Recklinghausen <crecklin@redhat.com> Merged-by: Lucas Zampieri <lzampier@redhat.com> |
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| .. | ||
| Makefile | ||
| compat.c | ||
| ipc_sysctl.c | ||
| mq_sysctl.c | ||
| mqueue.c | ||
| msg.c | ||
| msgutil.c | ||
| namespace.c | ||
| sem.c | ||
| shm.c | ||
| syscall.c | ||
| util.c | ||
| util.h | ||