Re: [PATCH] lto: Add __noreorder and mark initcalls __noreorder

2015-04-10 Thread Andi Kleen
On Fri, Apr 10, 2015 at 02:36:29PM -0700, Andrew Morton wrote: > On Thu, 9 Apr 2015 01:50:23 +0200 Andi Kleen wrote: > > > > Head is spinning a bit. As this all appears to be shiny new > > > added-by-andi gcc functionality, it would be useful if we could have a > > > few more words describing wh

Re: [PATCH] lto: Add __noreorder and mark initcalls __noreorder

2015-04-10 Thread Andrew Morton
On Thu, 9 Apr 2015 01:50:23 +0200 Andi Kleen wrote: > > Head is spinning a bit. As this all appears to be shiny new > > added-by-andi gcc functionality, it would be useful if we could have a > > few more words describing what it's all about. Reordering of what with > > respect to what and why a

Re: [PATCH] lto: Add __noreorder and mark initcalls __noreorder

2015-04-08 Thread Andi Kleen
Hi Andrew, On Wed, Apr 08, 2015 at 03:31:12PM -0700, Andrew Morton wrote: > On Wed, 8 Apr 2015 06:17:38 -0700 Andi Kleen wrote: > > > From: Andi Kleen > > > > gcc 5 has a new no_reorder attribute that prevents top level > > reordering only for that symbol. > > I'm having trouble locating gcc

Re: [PATCH] lto: Add __noreorder and mark initcalls __noreorder

2015-04-08 Thread Andrew Morton
On Wed, 8 Apr 2015 06:17:38 -0700 Andi Kleen wrote: > From: Andi Kleen > > gcc 5 has a new no_reorder attribute that prevents top level > reordering only for that symbol. I'm having trouble locating gcc documentation which explains all this stuff. > Kernels don't like any reordering of initc

[PATCH] lto: Add __noreorder and mark initcalls __noreorder

2015-04-08 Thread Andi Kleen
From: Andi Kleen gcc 5 has a new no_reorder attribute that prevents top level reordering only for that symbol. Kernels don't like any reordering of initcalls between files, as several initcalls depend on each other. LTO previously needed to use -fno-toplevel-reordering to prevent boot failures.