From: Heiko Carstens <hca@linux.ibm.com>
To: Alexander Gordeev <agordeev@linux.ibm.com>,
Sven Schnelle <svens@linux.ibm.com>,
Vasily Gorbik <gor@linux.ibm.com>,
Christian Borntraeger <borntraeger@linux.ibm.com>,
Mete Durlu <meted@linux.ibm.com>,
Peter Zijlstra <peterz@infradead.org>,
Mark Rutland <mark.rutland@arm.com>,
Juergen Christ <jchrist@linux.ibm.com>,
Ilya Leoshkevich <iii@linux.ibm.com>
Cc: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Subject: [PATCH 07/12] s390/percpu: Use __PCPU_BEGIN() and __PCPU_END() for inline assemblies
Date: Thu, 17 Sep 2026 21:22:32 +0200 [thread overview]
Message-ID: <20260917192237.638324-8-hca@linux.ibm.com> (raw)
In-Reply-To: <20260917192237.638324-1-hca@linux.ibm.com>
Replace the use of MVIY_PERCPU(), AG_ALT(), and MVIY_ALT() within all
percpu inline assemblies with __PCPU_BEGIN() and __PCPU_END(), since
the begin and end of each inline assembly is the same.
Also use consistent names: e.g. __PCPU_MVIY() and __PCPU_AG() instead of
the previous MVIY_PERCPU() and AG_ALT().
Furthermore extract DEFINE_GR_NUM and UNDEF_GR_NUM which are used to
convert register strings to register numbers.
All of this should make the code more readable. No functional change.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
arch/s390/include/asm/percpu.h | 83 +++++++++++++++++-----------------
1 file changed, 42 insertions(+), 41 deletions(-)
diff --git a/arch/s390/include/asm/percpu.h b/arch/s390/include/asm/percpu.h
index 0df47ec2e6c7..78c3aaa138f7 100644
--- a/arch/s390/include/asm/percpu.h
+++ b/arch/s390/include/asm/percpu.h
@@ -92,42 +92,49 @@
*
* Inline assemblies making use of this typically have a code sequence like:
*
- * MVIY_PERCPU(...) <- start of percpu code section
- * AG_ALT(...) <- add percpu offset; must be the second instruction
- * atomic_op <- atomic op
- * MVIY_ALT(...) <- end of percpu code section
+ * __PCPU_BEGIN(...) <- start of percpu code section
+ * atomic_op <- atomic op
+ * __PCPU_END(...) <- end of percpu code section
*/
#define LC_ALT_ADDR __stringify(LOWCORE_ALT_ADDRESS)
-#define MVIY_PERCPU(disp, reg) \
- ".macro GEN_MVIY disp, reg\n" \
- ".set .Lreg,255\n" \
- ".irp rs,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15\n" \
- " .ifc \\reg,%%r\\rs\n" \
- " .set .Lreg,\\rs\n" \
+#define DEFINE_GR_NUM \
+ ".macro _GR_NUM opd, gr\n" \
+ ".set \\opd,255\n" \
+ ".irp rs,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15\n" \
+ " .ifc \\gr,%%r\\rs\n" \
+ " \\opd = \\rs\n" \
" .endif\n" \
".endr\n" \
- ".if .Lreg == 255\n" \
+ ".if \\opd == 255\n" \
" .error \"Illegal register number\"\n" \
".endif\n" \
- "mviy \\disp(%%r0),.Lreg\n" \
- ".endm\n" \
- ALTERNATIVE("GEN_MVIY " disp " , " reg "\n", \
- "GEN_MVIY " disp "+" LC_ALT_ADDR " , " reg "\n", \
- ALT_FEATURE(MFEATURE_LOWCORE)) \
- ".purgem GEN_MVIY\n"
+ ".endm\n"
-#define MVIY_ALT(disp) \
- ALTERNATIVE(" mviy " disp "(%%r0),0\n", \
- " mviy " disp "+" LC_ALT_ADDR "(%%r0),0\n", \
+#define UNDEF_GR_NUM \
+ ".purgem _GR_NUM\n"
+
+#define __PCPU_MVIY(lcreg, imm) \
+ ALTERNATIVE(" mviy " lcreg "(%%r0)," imm "\n", \
+ " mviy " lcreg "+" LC_ALT_ADDR "(%%r0)," imm "\n", \
ALT_FEATURE(MFEATURE_LOWCORE))
-#define AG_ALT(disp, reg) \
- ALTERNATIVE(" ag " reg ", " disp "(%%r0)\n", \
- " ag " reg ", " disp "+" LC_ALT_ADDR "(%%r0)\n", \
+#define __PCPU_AG(reg, lcoff) \
+ ALTERNATIVE(" ag " reg ", " lcoff "(%%r0)\n", \
+ " ag " reg ", " lcoff "+" LC_ALT_ADDR "(%%r0)\n", \
ALT_FEATURE(MFEATURE_LOWCORE))
+#define __PCPU_BEGIN(lcreg, lcoff, reg) \
+ DEFINE_GR_NUM \
+ "_GR_NUM .Lreg, " reg "\n" \
+ UNDEF_GR_NUM \
+ __PCPU_MVIY(lcreg, ".Lreg") \
+ __PCPU_AG(reg, lcoff)
+
+#define __PCPU_END(lcreg) \
+ __PCPU_MVIY(lcreg, "0")
+
#ifndef MARCH_HAS_Z196_FEATURES
#define this_cpu_add_4(pcp, val) arch_this_cpu_to_op_simple(pcp, val, +)
@@ -151,10 +158,9 @@ do { \
if (__builtin_constant_p(val__) && \
((szcast)val__ > -129) && ((szcast)val__ < 128)) { \
asm volatile( \
- MVIY_PERCPU("%[lcreg]","%[ptr__]") \
- AG_ALT("%[lcoff]", "%[ptr__]") \
+ __PCPU_BEGIN("%[lcreg]","%[lcoff]","%[ptr__]") \
op2 " 0(%[ptr__]),%[val__]\n" \
- MVIY_ALT("%[lcreg]") \
+ __PCPU_END("%[lcreg]") \
: [ptr__] "+&a" (ptr__), "+m" (*ptr__), \
"=m" (((struct lowcore *)0)->percpu_register) \
: [val__] "i" ((szcast)val__), \
@@ -164,10 +170,9 @@ do { \
: "cc"); \
} else { \
asm volatile( \
- MVIY_PERCPU("%[lcreg]", "%[ptr__]") \
- AG_ALT("%[lcoff]", "%[ptr__]") \
+ __PCPU_BEGIN("%[lcreg]","%[lcoff]","%[ptr__]") \
op1 " %[old__],%[val__],0(%[ptr__])\n" \
- MVIY_ALT("%[lcreg]") \
+ __PCPU_END("%[lcreg]") \
: [old__] "=&d" (old__), \
[ptr__] "+&a" (ptr__), "+m" (*ptr__), \
"=m" (((struct lowcore *)0)->percpu_register) \
@@ -190,10 +195,9 @@ do { \
\
ptr__ = PERCPU_PTR(&(pcp)); \
asm_inline volatile( \
- MVIY_PERCPU("%[lcreg]","%[ptr__]") \
- AG_ALT("%[lcoff]","%[ptr__]") \
+ __PCPU_BEGIN("%[lcreg]","%[lcoff]","%[ptr__]") \
op " %[old__],%[val__],0(%[ptr__])\n" \
- MVIY_ALT("%[lcreg]") \
+ __PCPU_END("%[lcreg]") \
: [old__] "=&d" (old__), \
[ptr__] "+&a" (ptr__), "+m" (*ptr__), \
"=m" (((struct lowcore *)0)->percpu_register) \
@@ -216,10 +220,9 @@ do { \
\
ptr__ = PERCPU_PTR(&(pcp)); \
asm_inline volatile( \
- MVIY_PERCPU("%[lcreg]","%[ptr__]") \
- AG_ALT("%[lcoff]","%[ptr__]") \
+ __PCPU_BEGIN("%[lcreg]","%[lcoff]","%[ptr__]") \
op " %[old__],%[val__],0(%[ptr__])\n" \
- MVIY_ALT("%[lcreg]") \
+ __PCPU_END("%[lcreg]") \
: [old__] "=&d" (old__), \
[ptr__] "+&a" (ptr__), "+m" (*ptr__), \
"=m" (((struct lowcore *)0)->percpu_register) \
@@ -245,10 +248,9 @@ do { \
\
ptr__ = PERCPU_PTR(&(pcp)); \
asm_inline volatile( \
- MVIY_PERCPU("%[lcreg]","%[ptr__]") \
- AG_ALT("%[lcoff]","%[ptr__]") \
+ __PCPU_BEGIN("%[lcreg]","%[lcoff]","%[ptr__]") \
op " %[res__],0(%[ptr__])\n" \
- MVIY_ALT("%[lcreg]") \
+ __PCPU_END("%[lcreg]") \
: [res__] "=&d" (res__), [ptr__] "+&a" (ptr__), \
"=m" (((struct lowcore *)0)->percpu_register) \
: [lcreg] "i" (LC_PERCPU_REGISTER), \
@@ -271,10 +273,9 @@ do { \
\
ptr__ = PERCPU_PTR(&(pcp)); \
asm_inline volatile( \
- MVIY_PERCPU("%[lcreg]","%[ptr__]") \
- AG_ALT("%[lcoff]","%[ptr__]") \
+ __PCPU_BEGIN("%[lcreg]","%[lcoff]","%[ptr__]") \
op " %[val__],0(%[ptr__])\n" \
- MVIY_ALT("%[lcreg]") \
+ __PCPU_END("%[lcreg]") \
: [ptr__] "+&a" (ptr__), "=m" (*ptr__), \
"=m" (((struct lowcore *)0)->percpu_register) \
: [val__] "d" (val__), \
--
2.53.0
next prev parent reply other threads:[~2026-09-17 19:22 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-17 19:22 [PATCH 00/12] s390: More this_cpu_*() changes Heiko Carstens
2026-09-17 19:22 ` [PATCH 01/12] s390/percpu: Fix comment typo Heiko Carstens
2026-09-17 19:22 ` [PATCH 02/12] s390/percpu: Add sanity check to GEN_MVIY macro Heiko Carstens
2026-09-17 19:22 ` [PATCH 03/12] s390/lowcore: Remove _AC() from LOWCORE_ALT_ADDRESS Heiko Carstens
2026-09-17 19:22 ` [PATCH 04/12] s390/percpu: Let MVIY_PERCPU() calculate alternative displacement Heiko Carstens
2026-09-17 19:22 ` [PATCH 05/12] s390/percpu/lowcore: Add and use LC_PERCPU lowcore offset defines Heiko Carstens
2026-09-17 19:22 ` [PATCH 06/12] s390/percpu: Rename inline assembly symbolic names Heiko Carstens
2026-09-17 19:22 ` Heiko Carstens [this message]
2026-09-17 19:22 ` [PATCH 08/12] s390/percpu: Use percpu code section for this_cpu_cmpxchg128() Heiko Carstens
2026-09-17 19:22 ` [PATCH 09/12] s390/percpu: Use percpu code section for this_cpu_xchg() Heiko Carstens
2026-09-17 19:22 ` [PATCH 10/12] s390/percpu: Use percpu code section for this_cpu_cmpxchg() Heiko Carstens
2026-09-17 19:22 ` [PATCH 11/12] s390: Add CC_HAS_ASM_M_FORMAT_FLAG config option Heiko Carstens
2026-09-17 19:22 ` [PATCH 12/12] s390/percpu: Rework to simplify percpu_entry() and percpu_exit() Heiko Carstens
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260917192237.638324-8-hca@linux.ibm.com \
--to=hca@linux.ibm.com \
--cc=agordeev@linux.ibm.com \
--cc=borntraeger@linux.ibm.com \
--cc=gor@linux.ibm.com \
--cc=iii@linux.ibm.com \
--cc=jchrist@linux.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=meted@linux.ibm.com \
--cc=peterz@infradead.org \
--cc=svens@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®