diff options
Diffstat (limited to 'debian/patches-rt/0306-sched-migrate_enable-Use-select_fallback_rq.patch')
| -rw-r--r-- | debian/patches-rt/0306-sched-migrate_enable-Use-select_fallback_rq.patch | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/debian/patches-rt/0306-sched-migrate_enable-Use-select_fallback_rq.patch b/debian/patches-rt/0306-sched-migrate_enable-Use-select_fallback_rq.patch new file mode 100644 index 000000000..8177c1f0a --- /dev/null +++ b/debian/patches-rt/0306-sched-migrate_enable-Use-select_fallback_rq.patch @@ -0,0 +1,62 @@ +From: Scott Wood <swood@redhat.com> +Date: Sat, 12 Oct 2019 01:52:12 -0500 +Subject: [PATCH 306/342] sched: migrate_enable: Use select_fallback_rq() +Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=b19de5d2c7678334eef4c5e764fcbe08f4fce1f6 + +[ Upstream commit adfa969d4cfcc995a9d866020124e50f1827d2d1 ] + +migrate_enable() currently open-codes a variant of select_fallback_rq(). +However, it does not have the "No more Mr. Nice Guy" fallback and thus +it will pass an invalid CPU to the migration thread if cpus_mask only +contains a CPU that is !active. + +Signed-off-by: Scott Wood <swood@redhat.com> +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> +--- + kernel/sched/core.c | 25 ++++++++++--------------- + 1 file changed, 10 insertions(+), 15 deletions(-) + +diff --git a/kernel/sched/core.c b/kernel/sched/core.c +index 6f91ee2b7e91..7eb3037c0b35 100644 +--- a/kernel/sched/core.c ++++ b/kernel/sched/core.c +@@ -7329,6 +7329,7 @@ void migrate_enable(void) + if (p->migrate_disable_update) { + struct rq *rq; + struct rq_flags rf; ++ int cpu = task_cpu(p); + + rq = task_rq_lock(p, &rf); + update_rq_clock(rq); +@@ -7338,21 +7339,15 @@ void migrate_enable(void) + + p->migrate_disable_update = 0; + +- WARN_ON(smp_processor_id() != task_cpu(p)); +- if (!cpumask_test_cpu(task_cpu(p), &p->cpus_mask)) { +- const struct cpumask *cpu_valid_mask = cpu_active_mask; +- struct migration_arg arg; +- unsigned int dest_cpu; +- +- if (p->flags & PF_KTHREAD) { +- /* +- * Kernel threads are allowed on online && !active CPUs +- */ +- cpu_valid_mask = cpu_online_mask; +- } +- dest_cpu = cpumask_any_and(cpu_valid_mask, &p->cpus_mask); +- arg.task = p; +- arg.dest_cpu = dest_cpu; ++ WARN_ON(smp_processor_id() != cpu); ++ if (!cpumask_test_cpu(cpu, &p->cpus_mask)) { ++ struct migration_arg arg = { p }; ++ struct rq_flags rf; ++ ++ rq = task_rq_lock(p, &rf); ++ update_rq_clock(rq); ++ arg.dest_cpu = select_fallback_rq(cpu, p); ++ task_rq_unlock(rq, p, &rf); + + unpin_current_cpu(); + preempt_lazy_enable(); |