On Sunday 27 January 2008 17:03, Andrew Morton wrote: > > On Fri, 25 Jan 2008 14:03:25 +0800 Shaohua Li <[EMAIL PROTECTED]> > > wrote: > > > > - if (!page->mapping) > > + if (!page->mapping) { > > + if (!PageAnon(page) && PagePrivate(page)) > > + try_to_release_page(page, GFP_KERNEL); > > goto rcu_unlock; > > + } > > We call something(GFP_KERNEL) under rcu_read_lock()? I've lost track of > the myriad flavours of rcu which we purport to support, but I don't think > they'll all like us blocking under rcu_read_lock(). > > We _won't_ block, because try_to_release_page() will see the NULL ->mapping > and will call the non-blocking try_to_free_buffers(). But still, it looks > bad, and will cause problems if someone decides to add a might_sleep_if() > to try_to_release_page(). > > So... I'd suggest that it would be better to add an apologetic comment and > call direct into try_to_free_buffers().
You're right, but can't we just rcu_read_unlock() before try_to_release_page? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/