aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/include/asm/vdso/processor.h (follow)
AgeCommit message (Collapse)AuthorFilesLines
2025-09-01powerpc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headersThomas Huth1-2/+2
While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembler code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This is bad since macros starting with two underscores are names that are reserved by the C language. It can also be very confusing for the developers when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize now on the __ASSEMBLER__ macro that is provided by the compilers. This is almost a completely mechanical patch (done with a simple "sed -i" statement), apart from tweaking two comments manually in arch/powerpc/include/asm/bug.h and arch/powerpc/include/asm/kasan.h (which did not have proper underscores at the end) and fixing a checkpatch error about spaces in arch/powerpc/include/asm/spu_csa.h. Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250801082007.32904-3-thuth@redhat.com
2022-09-28powerpc/64s: Make POWER10 and later use pause_short in cpu_relax loopsNicholas Piggin1-1/+7
We want to move away from using SMT priority updates for cpu_relax, and use a 'wait' instruction which is similar to x86. As well as being a much better fit for what everybody else uses and tests with, priority nops are stateful which is nasty (interrupts have to consider they might be taken at a different priority), and they're expensive to execute, similar to a mtSPR which can effect other threads in the pipe. This has shown to give results that are less affected by code alignment on benchmarks that cause a lot of spin waiting (e.g., rwsem contention on unixbench filesystem benchmarks) on POWER10. QEMU TCG only supports this instruction correctly since v7.1, versions without the fix may cause hangs whne running POWER10 CPUs. Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Fix checkpatch warnings RE the macros] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220920122259.363092-2-npiggin@gmail.com
2021-08-27powerpc: Redefine HMT_xxx macros as empty on PPC32Christophe Leroy1-0/+9
HMT_xxx macros are macros for adjusting thread priority (hardware multi-threading) are macros inherited from PPC64 via commit 5f7c690728ac ("[PATCH] powerpc: Merged ppc_asm.h") Those instructions are pointless on PPC32, but some common fonctions like arch_cpu_idle() use them. So make them empty on PPC32 to avoid those instructions. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c5a07fadea33d640ad10cecf0ac8faaec1c524e0.1629898474.git.christophe.leroy@csgroup.eu
2020-12-04powerpc/processor: Move cpu_relax() into asm/vdso/processor.hChristophe Leroy1-0/+23
cpu_relax() need to be in asm/vdso/processor.h to be used by the C VDSO generic library. Move it there. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201126131006.2431205-2-mpe@ellerman.id.au