diff options
Diffstat (limited to 'Documentation/features/sched/membarrier-sync-core/arch-support.txt')
| -rw-r--r-- | Documentation/features/sched/membarrier-sync-core/arch-support.txt | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/Documentation/features/sched/membarrier-sync-core/arch-support.txt b/Documentation/features/sched/membarrier-sync-core/arch-support.txt index 883d33b265d6..7425d2b994a3 100644 --- a/Documentation/features/sched/membarrier-sync-core/arch-support.txt +++ b/Documentation/features/sched/membarrier-sync-core/arch-support.txt @@ -5,11 +5,27 @@ # # Architecture requirements # -# * arm/arm64/powerpc +# * arm/arm64/powerpc/s390 # # Rely on implicit context synchronization as a result of exception return # when returning from IPI handler, and when returning to user-space. # +# * riscv +# +# riscv uses xRET as return from interrupt and to return to user-space. +# +# Given that xRET is not core serializing, we rely on FENCE.I for providing +# core serialization: +# +# - by calling sync_core_before_usermode() on return from interrupt (cf. +# ipi_sync_core()), +# +# - via switch_mm() and sync_core_before_usermode() (respectively, for +# uthread->uthread and kthread->uthread transitions) before returning +# to user-space. +# +# The serialization in switch_mm() is activated by prepare_sync_core_cmd(). +# # * x86 # # x86-32 uses IRET as return from interrupt, which takes care of the IPI. @@ -34,19 +50,17 @@ | arm: | ok | | arm64: | ok | | csky: | TODO | - | h8300: | TODO | | hexagon: | TODO | - | ia64: | TODO | + | loongarch: | TODO | | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | - | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | - | riscv: | TODO | - | s390: | TODO | + | riscv: | ok | + | s390: | ok | | sh: | TODO | | sparc: | TODO | | um: | TODO | |