Paul Burton e11124d8ff MIPS: Remove r2_emul_return from struct thread_info ... The r2_emul_return field in struct thread_info was used in order to take an alternate codepath when returning to userland, which (besides not implementing certain features) effectively used the eretnc instruction in place of eret. The difference is that eretnc doesn't clear LLBit, and therefore doesn't cause a linked load & store sequence to fail due to emulation like eret would. The reason eret would usually be used to clear LLBit is so that after context switching we ensure that a load performed by one task doesn't influence another task. However commit 7c151d3d5d ("MIPS: Make use of the ERETNC instruction on MIPS R6") which introduced the r2_emul_return field and conditional use of eretnc also for some reason began explicitly clearing LLBit during context switches - despite retaining the use of eret for everything but returns from the pre-r6 instruction emulation code. As LLBit is cleared upon context switches anyway, simplify this by using eretnc unconditionally for MIPSr6 kernels. This allows us to remove the 4 byte r2_emul_return boolean from struct thread_info, simplify the return to user code in entry.S and avoid the overhead of tracking & checking state which we don't need. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14408/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>		2017-01-03 16:34:41 +01:00
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asm	MIPS: Remove r2_emul_return from struct thread_info	2017-01-03 16:34:41 +01:00
uapi/asm	tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING	2016-11-30 10:04:25 -05:00