diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2025-10-27 09:44:45 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2025-11-04 08:32:14 +0100 |
| commit | 4b7de6df20d43dd651031aef8d818fa5da981dbf (patch) | |
| tree | b4a5bc7da9f59d105c1be32f36c0d63e6054c2f5 /include/linux/rseq.h | |
| parent | 4fc9225d19ad6289c03340a520d35e3a6d1aebed (diff) | |
rseq: Cache CPU ID and MM CID values
In preparation for rewriting RSEQ exit to user space handling provide
storage to cache the CPU ID and MM CID values which were written to user
space. That prepares for a quick check, which avoids the update when
nothing changed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251027084306.841964081@linutronix.de
Diffstat (limited to 'include/linux/rseq.h')
| -rw-r--r-- | include/linux/rseq.h | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/include/linux/rseq.h b/include/linux/rseq.h index ab91b1e6bb4a..d315a92afb36 100644 --- a/include/linux/rseq.h +++ b/include/linux/rseq.h @@ -57,6 +57,7 @@ static inline void rseq_virt_userspace_exit(void) static inline void rseq_reset(struct task_struct *t) { memset(&t->rseq, 0, sizeof(t->rseq)); + t->rseq.ids.cpu_cid = ~0ULL; } static inline void rseq_execve(struct task_struct *t) @@ -70,10 +71,12 @@ static inline void rseq_execve(struct task_struct *t) */ static inline void rseq_fork(struct task_struct *t, u64 clone_flags) { - if (clone_flags & CLONE_VM) + if (clone_flags & CLONE_VM) { rseq_reset(t); - else + } else { t->rseq = current->rseq; + t->rseq.ids.cpu_cid = ~0ULL; + } } #else /* CONFIG_RSEQ */ |