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Peter Anvin" Content-Type: multipart/mixed; boundary="0000000000001a60c40632dfce69" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250415_235759_648722_621DB623 X-CRM114-Status: GOOD ( 27.85 ) X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org --0000000000001a60c40632dfce69 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Apr 16, 2025 at 7:53=E2=80=AFAM Uros Bizjak wro= te: > > On Tue, Apr 15, 2025 at 7:56=E2=80=AFPM David Laight > wrote: > > > > On Mon, 14 Apr 2025 16:55:57 +0200 > > Uros Bizjak wrote: > > > > > Current minimum required version of binutils is 2.25, > > > which supports PAUSE instruction mnemonic. > > > > > > Replace "REP; NOP" with this proper mnemonic. > > > > > > No functional change intended. > > > > > > Signed-off-by: Uros Bizjak > > > Cc: Richard Weinberger > > > Cc: Anton Ivanov > > > Cc: Johannes Berg > > > Cc: Thomas Gleixner > > > Cc: Ingo Molnar > > > Cc: Borislav Petkov > > > Cc: Dave Hansen > > > Cc: "H. Peter Anvin" > > > --- > > > arch/x86/um/asm/processor.h | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/arch/x86/um/asm/processor.h b/arch/x86/um/asm/processor.= h > > > index 478710384b34..233a7a0d29c9 100644 > > > --- a/arch/x86/um/asm/processor.h > > > +++ b/arch/x86/um/asm/processor.h > > > @@ -24,7 +24,7 @@ > > > /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. *= / > > > static __always_inline void rep_nop(void) > > > { > > > - __asm__ __volatile__("rep;nop": : :"memory"); > > > + __asm__ __volatile__("pause": : :"memory"); > > > } > > > > > > > That only makes sense if you also change the function name. > > This function is used in several places, and is also defined for x86 > in arch/x86/include/asm/vdso/processor.h. The renaming should be > coordinated with x86 and should definitely be a separate patch. Something like the attached patch that also moves (duplicated) function definition to a shared place. 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