Re: [PATCH v3 5/5] KVM/x86/lbr: lazy save the guest lbr stack

[Wei Wang]

On 09/20/2018 08:37 PM, Peter Zijlstra wrote:
On Thu, Sep 20, 2018 at 06:05:59PM +0800, Wei Wang wrote:
  /**
+ * lbr_select_user_callstack - check if the user callstack mode is set
+ *
+ * @lbr_select: the lbr select msr
+ *
+ * Returns: true if the msr is configured to the user callstack mode.
+ * Otherwise, false.
+ *
+ */
+bool lbr_select_user_callstack(u64 lbr_select)
+{
+       return !!(lbr_select & LBR_USER_CALLSTACK);
+}
+EXPORT_SYMBOL_GPL(lbr_select_user_callstack);
That function is pure and tiny, wth is that an exported symbol and not
an inline?
Thanks Peter for the comments.
Because this function uses the LBR_ macros which are defined in this 
lbr.c file.
Do you think it would be OK to move all the above LBR_ macros to 
asm/perf_event.h?

Best,
Wei