mbox series

[v2,bpf,0/3] vmalloc: bpf: introduce VM_ALLOW_HUGE_VMAP

Message ID 20220411231808.667073-1-song@kernel.org (mailing list archive)
Headers show
Series vmalloc: bpf: introduce VM_ALLOW_HUGE_VMAP | expand

Message

Song Liu April 11, 2022, 11:18 p.m. UTC 
Changes v1 => v2:
1. Add vmalloc_huge(). (Christoph Hellwig)
2. Add module_alloc_huge(). (Christoph Hellwig)
3. Add Fixes tag and Link tag. (Thorsten Leemhuis)

Enabling HAVE_ARCH_HUGE_VMALLOC on x86_64 and use it for bpf_prog_pack has
caused some issues [1], as many users of vmalloc are not yet ready to
handle huge pages. To enable a more smooth transition to use huge page
backed vmalloc memory, this set replaces VM_NO_HUGE_VMAP flag with an new
opt-in flag, VM_ALLOW_HUGE_VMAP. More discussions about this topic can be
found at [2].

Patch 1 removes VM_NO_HUGE_VMAP and adds VM_ALLOW_HUGE_VMAP.
Patch 2 uses VM_ALLOW_HUGE_VMAP in bpf_prog_pack.

[1] https://lore.kernel.org/lkml/20220204185742.271030-1-song@kernel.org/
[2] https://lore.kernel.org/linux-mm/20220330225642.1163897-1-song@kernel.org/

Song Liu (3):
  vmalloc: replace VM_NO_HUGE_VMAP with VM_ALLOW_HUGE_VMAP
  module: introduce module_alloc_huge
  bpf: use vmalloc with VM_ALLOW_HUGE_VMAP for bpf_prog_pack

 arch/Kconfig                 |  6 ++----
 arch/powerpc/kernel/module.c |  2 +-
 arch/s390/kvm/pv.c           |  2 +-
 arch/x86/kernel/module.c     | 21 +++++++++++++++++++
 include/linux/moduleloader.h |  5 +++++
 include/linux/vmalloc.h      |  4 ++--
 kernel/bpf/core.c            |  9 +++++----
 kernel/module.c              |  8 ++++++++
 mm/vmalloc.c                 | 39 +++++++++++++++++++-----------------
 9 files changed, 66 insertions(+), 30 deletions(-)

--
2.30.2

Comments

Luis Chamberlain April 12, 2022, 3:38 p.m. UTC | #1 
On Mon, Apr 11, 2022 at 04:18:05PM -0700, Song Liu wrote:
> Changes v1 => v2:
> 1. Add vmalloc_huge(). (Christoph Hellwig)
> 2. Add module_alloc_huge(). (Christoph Hellwig)
> 3. Add Fixes tag and Link tag. (Thorsten Leemhuis)
> 
> Enabling HAVE_ARCH_HUGE_VMALLOC on x86_64 and use it for bpf_prog_pack has
> caused some issues [1], as many users of vmalloc are not yet ready to
> handle huge pages. To enable a more smooth transition to use huge page
> backed vmalloc memory, this set replaces VM_NO_HUGE_VMAP flag with an new
> opt-in flag, VM_ALLOW_HUGE_VMAP. More discussions about this topic can be
> found at [2].
> 
> Patch 1 removes VM_NO_HUGE_VMAP and adds VM_ALLOW_HUGE_VMAP.
> Patch 2 uses VM_ALLOW_HUGE_VMAP in bpf_prog_pack.
> 
> [1] https://lore.kernel.org/lkml/20220204185742.271030-1-song@kernel.org/
> [2] https://lore.kernel.org/linux-mm/20220330225642.1163897-1-song@kernel.org/
> 
> Song Liu (3):
>   vmalloc: replace VM_NO_HUGE_VMAP with VM_ALLOW_HUGE_VMAP
>   module: introduce module_alloc_huge
>   bpf: use vmalloc with VM_ALLOW_HUGE_VMAP for bpf_prog_pack
> 
>  arch/Kconfig                 |  6 ++----
>  arch/powerpc/kernel/module.c |  2 +-
>  arch/s390/kvm/pv.c           |  2 +-
>  arch/x86/kernel/module.c     | 21 +++++++++++++++++++
>  include/linux/moduleloader.h |  5 +++++
>  include/linux/vmalloc.h      |  4 ++--
>  kernel/bpf/core.c            |  9 +++++----
>  kernel/module.c              |  8 ++++++++

Please use modules-next [0] as that has queued up changes which change
kernel/module.c quite a bit.

[0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=modules-next

 Luis
Song Liu April 13, 2022, 12:35 a.m. UTC | #2 
Hi Luis,

On Tue, Apr 12, 2022 at 8:38 AM Luis Chamberlain <mcgrof@kernel.org> wrote:
>
> On Mon, Apr 11, 2022 at 04:18:05PM -0700, Song Liu wrote:
> > Changes v1 => v2:
> > 1. Add vmalloc_huge(). (Christoph Hellwig)
> > 2. Add module_alloc_huge(). (Christoph Hellwig)
> > 3. Add Fixes tag and Link tag. (Thorsten Leemhuis)
> >
> > Enabling HAVE_ARCH_HUGE_VMALLOC on x86_64 and use it for bpf_prog_pack has
> > caused some issues [1], as many users of vmalloc are not yet ready to
> > handle huge pages. To enable a more smooth transition to use huge page
> > backed vmalloc memory, this set replaces VM_NO_HUGE_VMAP flag with an new
> > opt-in flag, VM_ALLOW_HUGE_VMAP. More discussions about this topic can be
> > found at [2].
> >
> > Patch 1 removes VM_NO_HUGE_VMAP and adds VM_ALLOW_HUGE_VMAP.
> > Patch 2 uses VM_ALLOW_HUGE_VMAP in bpf_prog_pack.
> >
> > [1] https://lore.kernel.org/lkml/20220204185742.271030-1-song@kernel.org/
> > [2] https://lore.kernel.org/linux-mm/20220330225642.1163897-1-song@kernel.org/
> >
> > Song Liu (3):
> >   vmalloc: replace VM_NO_HUGE_VMAP with VM_ALLOW_HUGE_VMAP
> >   module: introduce module_alloc_huge
> >   bpf: use vmalloc with VM_ALLOW_HUGE_VMAP for bpf_prog_pack
> >
> >  arch/Kconfig                 |  6 ++----
> >  arch/powerpc/kernel/module.c |  2 +-
> >  arch/s390/kvm/pv.c           |  2 +-
> >  arch/x86/kernel/module.c     | 21 +++++++++++++++++++
> >  include/linux/moduleloader.h |  5 +++++
> >  include/linux/vmalloc.h      |  4 ++--
> >  kernel/bpf/core.c            |  9 +++++----
> >  kernel/module.c              |  8 ++++++++
>
> Please use modules-next [0] as that has queued up changes which change
> kernel/module.c quite a bit.
>
> [0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=modules-next

We are hoping to ship this set to fix some issues with 5.18. So I guess it
shouldn't go through modules-next branch? Would this work for you?
We are adding a new API module_alloc_huge(), so it shouldn't break
existing features.

Thanks,
Song