diff options
Diffstat (limited to 'include/linux/rseq_entry.h')
| -rw-r--r-- | include/linux/rseq_entry.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/include/linux/rseq_entry.h b/include/linux/rseq_entry.h index 37444e80fd45..aa1c0464a16c 100644 --- a/include/linux/rseq_entry.h +++ b/include/linux/rseq_entry.h @@ -368,6 +368,35 @@ efault: return false; } +/* + * Update user space with new IDs and conditionally check whether the task + * is in a critical section. + */ +static rseq_inline bool rseq_update_usr(struct task_struct *t, struct pt_regs *regs, + struct rseq_ids *ids, u32 node_id) +{ + u64 csaddr; + + if (!rseq_set_ids_get_csaddr(t, ids, node_id, &csaddr)) + return false; + + /* + * On architectures which utilize the generic entry code this + * allows to skip the critical section when the entry was not from + * a user space interrupt, unless debug mode is enabled. + */ + if (IS_ENABLED(CONFIG_GENERIC_IRQ_ENTRY)) { + if (!static_branch_unlikely(&rseq_debug_enabled)) { + if (likely(!t->rseq.event.user_irq)) + return true; + } + } + if (likely(!csaddr)) + return true; + /* Sigh, this really needs to do work */ + return rseq_update_user_cs(t, regs, csaddr); +} + static __always_inline void rseq_exit_to_user_mode(void) { struct rseq_event *ev = ¤t->rseq.event; |