From: Yury Norov Date: Thu, 19 Mar 2026 03:36:46 +0000 (-0400) Subject: powerpc/xive: rework xive_find_target_in_mask() X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ce7c43b0871989b4c665cceb9720d79b933c1818;p=thirdparty%2Fkernel%2Flinux.git powerpc/xive: rework xive_find_target_in_mask() Switch the function to using modern cpumask API and drop most of the housekeeping code. Notice, if first >= nr_cpu_ids, for_each_cpu_wrap() iterator behaves just like for_each_cpu(), i.e. begins from 0. So even if WARN_ON() is triggered, no special handling is needed. Signed-off-by: Yury Norov Tested-by: Mukesh Kumar Chaurasiya (IBM) Reviewed-by: Shrikanth Hegde Reviewed-by: Mukesh Kumar Chaurasiya (IBM) Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20260319033647.881246-3-ynorov@nvidia.com --- diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c index 33e9fb3436e1a..c120be73d149f 100644 --- a/arch/powerpc/sysdev/xive/common.c +++ b/arch/powerpc/sysdev/xive/common.c @@ -548,40 +548,21 @@ static void xive_dec_target_count(int cpu) static int xive_find_target_in_mask(const struct cpumask *mask, unsigned int fuzz) { - int cpu, first, num, i; + int cpu, first; /* Pick up a starting point CPU in the mask based on fuzz */ - num = cpumask_weight(mask); - first = fuzz % num; - - /* Locate it */ - cpu = cpumask_first(mask); - for (i = 0; i < first && cpu < nr_cpu_ids; i++) - cpu = cpumask_next(cpu, mask); - - /* Sanity check */ - if (WARN_ON(cpu >= nr_cpu_ids)) - cpu = cpumask_first(cpu_online_mask); - - /* Remember first one to handle wrap-around */ - first = cpu; + fuzz %= cpumask_weight(mask); + first = cpumask_nth(fuzz, mask); + WARN_ON(first >= nr_cpu_ids); /* * Now go through the entire mask until we find a valid * target. */ - do { - /* - * We re-check online as the fallback case passes us - * an untested affinity mask - */ + for_each_cpu_wrap(cpu, mask, first) { if (cpu_online(cpu) && xive_try_pick_target(cpu)) return cpu; - cpu = cpumask_next(cpu, mask); - /* Wrap around */ - if (cpu >= nr_cpu_ids) - cpu = cpumask_first(mask); - } while (cpu != first); + } return -1; }