Re: [PATCH 1/3] powerpc/cacheinfo: add cacheinfo_teardown, cacheinfo_rebuild
From: Gautham R Shenoy <hidden>
Date: 2019-06-14 05:57:02
On Wed, Jun 12, 2019 at 10:15 AM Nathan Lynch [off-list ref] wrote:
Allow external callers to force the cacheinfo code to release all its
references to cache nodes, e.g. before processing device tree updates
post-migration, and to rebuild the hierarchy afterward.
CPU online/offline must be blocked by callers; enforce this.
Fixes: 410bccf97881 ("powerpc/pseries: Partition migration in the kernel")
Signed-off-by: Nathan Lynch <redacted>Reviewed-by: Gautham R. Shenoy <redacted>
quoted hunk ↗ jump to hunk
--- arch/powerpc/kernel/cacheinfo.c | 21 +++++++++++++++++++++ arch/powerpc/kernel/cacheinfo.h | 4 ++++ 2 files changed, 25 insertions(+)diff --git a/arch/powerpc/kernel/cacheinfo.c b/arch/powerpc/kernel/cacheinfo.c index 862e2890bd3d..42c559efe060 100644 --- a/arch/powerpc/kernel/cacheinfo.c +++ b/arch/powerpc/kernel/cacheinfo.c@@ -896,4 +896,25 @@ void cacheinfo_cpu_offline(unsigned int cpu_id) if (cache) cache_cpu_clear(cache, cpu_id); } + +void cacheinfo_teardown(void) +{ + unsigned int cpu; + + lockdep_assert_cpus_held(); + + for_each_online_cpu(cpu) + cacheinfo_cpu_offline(cpu); +} + +void cacheinfo_rebuild(void) +{ + unsigned int cpu; + + lockdep_assert_cpus_held(); + + for_each_online_cpu(cpu) + cacheinfo_cpu_online(cpu); +} + #endif /* (CONFIG_PPC_PSERIES && CONFIG_SUSPEND) || CONFIG_HOTPLUG_CPU */diff --git a/arch/powerpc/kernel/cacheinfo.h b/arch/powerpc/kernel/cacheinfo.h index 955f5e999f1b..52bd3fc6642d 100644 --- a/arch/powerpc/kernel/cacheinfo.h +++ b/arch/powerpc/kernel/cacheinfo.h@@ -6,4 +6,8 @@ extern void cacheinfo_cpu_online(unsigned int cpu_id); extern void cacheinfo_cpu_offline(unsigned int cpu_id); +/* Allow migration/suspend to tear down and rebuild the hierarchy. */ +extern void cacheinfo_teardown(void); +extern void cacheinfo_rebuild(void); + #endif /* _PPC_CACHEINFO_H */ --2.20.1
-- Thanks and Regards gautham.