linux/drivers/virtio
Vlastimil Babka e871c7feeb FROMGIT: mm, page_poison: use static key more efficiently
Commit 11c9c7edae ("mm/page_poison.c: replace bool variable with static
key") changed page_poisoning_enabled() to a static key check.  However,
the function is not inlined, so each check still involves a function call
with overhead not eliminated when page poisoning is disabled.

Analogically to how debug_pagealloc is handled, this patch converts
page_poisoning_enabled() back to boolean check, and introduces
page_poisoning_enabled_static() for fast paths.  Both functions are
inlined.

The function kernel_poison_pages() is also called unconditionally and does
the static key check inside.  Remove it from there and put it to callers.
Also split it to two functions kernel_poison_pages() and
kernel_unpoison_pages() instead of the confusing bool parameter.

Also optimize the check that enables page poisoning instead of
debug_pagealloc for architectures without proper debug_pagealloc support.
Move the check to init_mem_debugging_and_hardening() to enable a single
static key instead of having two static branches in
page_poisoning_enabled_static().

Link: https://lkml.kernel.org/r/20201113104033.22907-3-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Mateusz Nosek <mateusznosek0@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

(cherry picked from commit 8db26a3d47
 https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git akpm)
Bug: 182930667
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Ifc3fdf5cd58f3b8346bf81480df3836811e7458b
2021-03-24 15:09:16 -07:00
..
Kconfig ANDROID: GKI: Unhide VIRTIO_DMA_SHARED_BUFFER 2020-12-16 09:28:07 -08:00
Makefile virtio: fix build for configs without dma-bufs 2020-08-19 06:43:28 +02:00
virtio_balloon.c FROMGIT: mm, page_poison: use static key more efficiently 2021-03-24 15:09:16 -07:00
virtio_dma_buf.c ANDROID: virtio: disable virtio_dma_buf callback checks with CFI 2021-01-28 22:14:14 +00:00
virtio_input.c Merge 1f70935f63 ("Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc") into android-mainline 2020-10-27 11:47:16 +01:00
virtio_mem.c vhost,vdpa,virtio: cleanups, fixes 2020-10-23 11:00:57 -07:00
virtio_mmio.c virtio: Implement get_shm_region for MMIO transport 2020-09-10 10:05:58 +02:00
virtio_pci_common.c virtio-pci: check name when counting MSI-X vectors 2020-02-06 03:40:26 -05:00
virtio_pci_common.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 78 2019-05-24 17:37:51 +02:00
virtio_pci_legacy.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 78 2019-05-24 17:37:51 +02:00
virtio_pci_modern.c virtio: Implement get_shm_region for PCI transport 2020-09-10 10:05:58 +02:00
virtio_ring.c virtio_ring: Fix two use after free bugs 2020-12-30 11:54:00 +01:00
virtio_vdpa.c virtio_vdpa: legacy features handling 2020-08-05 11:08:40 -04:00
virtio.c vhost,vdpa,virtio: cleanups, fixes 2020-10-23 11:00:57 -07:00