mirror-linux/include
Menglong Dong c205cc7534 net: skb: prevent the split of kfree_skb_reason() by gcc
Sometimes, gcc will optimize the function by spliting it to two or
more functions. In this case, kfree_skb_reason() is splited to
kfree_skb_reason and kfree_skb_reason.part.0. However, the
function/tracepoint trace_kfree_skb() in it needs the return address
of kfree_skb_reason().

This split makes the call chains becomes:
  kfree_skb_reason() -> kfree_skb_reason.part.0 -> trace_kfree_skb()

which makes the return address that passed to trace_kfree_skb() be
kfree_skb().

Therefore, introduce '__fix_address', which is the combination of
'__noclone' and 'noinline', and apply it to kfree_skb_reason() to
prevent to from being splited or made inline.

(Is it better to simply apply '__noclone oninline' to kfree_skb_reason?
I'm thinking maybe other functions have the same problems)

Meanwhile, wrap 'skb_unref()' with 'unlikely()', as the compiler thinks
it is likely return true and splits kfree_skb_reason().

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24 09:47:51 +01:00
..
acpi Merge branch 'acpi-properties' 2022-08-11 19:21:03 +02:00
asm-generic locking/atomic: Make test_and_*_bit() ordered on failure 2022-08-16 09:19:43 -07:00
clocksource
crypto for-5.20/block-2022-08-04 2022-08-04 20:00:14 -07:00
drm
dt-bindings power supply and reset changes for the v6.0 series 2022-08-12 09:37:33 -07:00
keys
kunit
kvm
linux net: skb: prevent the split of kfree_skb_reason() by gcc 2022-08-24 09:47:51 +01:00
math-emu
media SPDX changes for 6.0-rc1 2022-08-04 12:12:54 -07:00
memory
misc
net net: dsa: use dsa_tree_for_each_cpu_port in dsa_tree_{setup,teardown}_master 2022-08-23 11:39:22 +02:00
pcmcia
ras mm, hwpoison: enable memory error handling on 1GB hugepage 2022-08-08 18:06:44 -07:00
rdma dma-mapping updates 2022-08-06 10:56:45 -07:00
rv
scsi SCSI misc on 20220813 2022-08-13 13:41:48 -07:00
soc net: mscc: ocelot: set up tag_8021q CPU ports independent of user port affinity 2022-08-23 11:39:22 +02:00
sound ASoC: More updates for v5.20 2022-08-01 15:26:40 +02:00
target scsi: target: core: De-RCU of se_lun and se_lun acl 2022-08-01 19:36:02 -04:00
trace * Xen timer fixes 2022-08-11 12:10:08 -07:00
uapi net: improve and fix netlink kdoc 2022-08-23 16:10:23 -07:00
ufs
vdso
video
xen x86/xen: Add support for HVMOP_set_evtchn_upcall_vector 2022-08-12 11:28:21 +02:00