Re: [PATCH v3 0/5] tools/rtla: Consolidate nr_cpus usage

From: Wander Lairson Costa

Date: Fri Feb 13 2026 - 08:56:17 EST


On Fri, Feb 13, 2026 at 01:52:29PM +0200, Costa Shulyupin wrote:
> sysconf(_SC_NPROCESSORS_CONF) (via get_nprocs_conf) reflects
> cpu_possible_mask, which is fixed at boot time, so querying it
> repeatedly is unnecessary.
>
> Replace multiple calls to sysconf(_SC_NPROCESSORS_CONF) with a single
> global nr_cpus variable initialized once at startup.


Reviewed-by: Wander Lairson Costa <wander@xxxxxxxxxx>

>
> V3:
> - Remove unneeded cpus parameter from timerlat BPF functions as
> requested by Wander Costa.
> v2:
> - Add `#pragma once` in timerlat_u.h to avoid redefinition errors with
> pre-C23 compilers.
>
> Costa Shulyupin (5):
> tools/rtla: Consolidate nr_cpus usage across all tools
> tools/rtla: Remove unneeded nr_cpus arguments
> tools/rtla: Remove unneeded nr_cpus members
> tools/rtla: Remove unneeded nr_cpus from for_each_monitored_cpu
> tools/rtla: Remove unneeded cpus parameter from timerlat BPF functions
>
> tools/tracing/rtla/src/common.c | 7 ++-
> tools/tracing/rtla/src/common.h | 4 +-
> tools/tracing/rtla/src/osnoise_hist.c | 26 +++++------
> tools/tracing/rtla/src/osnoise_top.c | 16 ++-----
> tools/tracing/rtla/src/timerlat.c | 9 ++--
> tools/tracing/rtla/src/timerlat_aa.c | 11 ++---
> tools/tracing/rtla/src/timerlat_bpf.c | 19 ++++----
> tools/tracing/rtla/src/timerlat_bpf.h | 12 ++---
> tools/tracing/rtla/src/timerlat_hist.c | 62 +++++++++++---------------
> tools/tracing/rtla/src/timerlat_top.c | 47 +++++++------------
> tools/tracing/rtla/src/timerlat_u.c | 9 ++--
> tools/tracing/rtla/src/timerlat_u.h | 1 +
> tools/tracing/rtla/src/utils.c | 10 +----
> 13 files changed, 88 insertions(+), 145 deletions(-)
>
> --
> 2.52.0
>