From: sxwjean@me.com
To: linuxppc-dev@lists.ozlabs.org
Cc: oleg@redhat.com, mpe@ellerman.id.au, benh@kernel.crashing.org,
paulus@samba.org, ravi.bangoria@linux.ibm.com,
christophe.leroy@csgroup.eu, npiggin@gmail.com,
aneesh.kumar@linux.ibm.com, sandipan@linux.ibm.com,
efremov@linux.com, peterx@redhat.com, akpm@linux-foundation.org,
linux-kernel@vger.kernel.org, Xiongwei Song <sxwjean@gmail.com>
Subject: [RFC PATCH 3/4] powerpc: Optimize register usage for dear register
Date: Mon, 26 Jul 2021 22:30:52 +0800 [thread overview]
Message-ID: <20210726143053.532839-3-sxwjean@me.com> (raw)
In-Reply-To: <20210726143053.532839-1-sxwjean@me.com>
From: Xiongwei Song <sxwjean@gmail.com>
Create an anonymous union for dar and dear regsiters, we can reference
dear to get the effective address when CONFIG_4xx=y or CONFIG_BOOKE=y.
Otherwise, reference dar. This makes code more clear.
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
---
arch/powerpc/include/asm/ptrace.h | 5 ++++-
arch/powerpc/include/uapi/asm/ptrace.h | 5 ++++-
arch/powerpc/kernel/process.c | 2 +-
arch/powerpc/kernel/ptrace/ptrace.c | 2 ++
arch/powerpc/kernel/traps.c | 5 ++++-
arch/powerpc/mm/fault.c | 2 +-
6 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index c252d04b1206..fa725e3238c2 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -43,7 +43,10 @@ struct pt_regs
unsigned long mq;
#endif
unsigned long trap;
- unsigned long dar;
+ union {
+ unsigned long dar;
+ unsigned long dear;
+ };
union {
unsigned long dsisr;
unsigned long esr;
diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h
index e357288b5f34..9ae150fb4c4b 100644
--- a/arch/powerpc/include/uapi/asm/ptrace.h
+++ b/arch/powerpc/include/uapi/asm/ptrace.h
@@ -52,7 +52,10 @@ struct pt_regs
unsigned long trap; /* Reason for being here */
/* N.B. for critical exceptions on 4xx, the dar and dsisr
fields are overloaded to hold srr0 and srr1. */
- unsigned long dar; /* Fault registers */
+ union {
+ unsigned long dar; /* Fault registers */
+ unsigned long dear;
+ };
union {
unsigned long dsisr; /* on Book-S used for DSISR */
unsigned long esr; /* on 4xx/Book-E used for ESR */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index f74af8f9133c..50436b52c213 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1499,7 +1499,7 @@ static void __show_regs(struct pt_regs *regs)
trap == INTERRUPT_DATA_STORAGE ||
trap == INTERRUPT_ALIGNMENT) {
if (IS_ENABLED(CONFIG_4xx) || IS_ENABLED(CONFIG_BOOKE))
- pr_cont("DEAR: "REG" ESR: "REG" ", regs->dar, regs->esr);
+ pr_cont("DEAR: "REG" ESR: "REG" ", regs->dear, regs->esr);
else
pr_cont("DAR: "REG" DSISR: %08lx ", regs->dar, regs->dsisr);
}
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index 00789ad2c4a3..969dca8b0718 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -373,6 +373,8 @@ void __init pt_regs_check(void)
offsetof(struct user_pt_regs, trap));
BUILD_BUG_ON(offsetof(struct pt_regs, dar) !=
offsetof(struct user_pt_regs, dar));
+ BUILD_BUG_ON(offsetof(struct pt_regs, dear) !=
+ offsetof(struct user_pt_regs, dear));
BUILD_BUG_ON(offsetof(struct pt_regs, dsisr) !=
offsetof(struct user_pt_regs, dsisr));
BUILD_BUG_ON(offsetof(struct pt_regs, esr) !=
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 2164f5705a0b..0796630d3d23 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1609,7 +1609,10 @@ DEFINE_INTERRUPT_HANDLER(alignment_exception)
}
bad:
if (user_mode(regs))
- _exception(sig, regs, code, regs->dar);
+ if (IS_ENABLED(CONFIG_4xx) || IS_ENABLED(CONFIG_BOOKE))
+ _exception(sig, regs, code, regs->dear);
+ else
+ _exception(sig, regs, code, regs->dar);
else
bad_page_fault(regs, sig);
}
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 62953d4e7c93..3db6b39a1178 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -542,7 +542,7 @@ static __always_inline void __do_page_fault(struct pt_regs *regs)
long err;
if (IS_ENABLED(CONFIG_4xx) || IS_ENABLED(CONFIG_BOOKE))
- err = ___do_page_fault(regs, regs->dar, regs->esr);
+ err = ___do_page_fault(regs, regs->dear, regs->esr);
else
err = ___do_page_fault(regs, regs->dar, regs->dsisr);
--
2.30.2
next prev parent reply other threads:[~2021-07-26 14:31 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-26 14:30 [RFC PATCH 1/4] powerpc: Optimize register usage for esr register sxwjean
2021-07-26 14:30 ` [RFC PATCH 2/4] powerpc/64e: Get esr offset with _ESR macro sxwjean
2021-07-26 14:30 ` sxwjean [this message]
2021-08-05 10:09 ` [RFC PATCH 3/4] powerpc: Optimize register usage for dear register Christophe Leroy
2021-08-06 3:16 ` Xiongwei Song
2021-07-26 14:30 ` [RFC PATCH 4/4] powerpc/64e: Get dear offset with _DEAR macro sxwjean
2021-08-05 10:06 ` [RFC PATCH 1/4] powerpc: Optimize register usage for esr register Christophe Leroy
2021-08-06 3:16 ` Xiongwei Song
2021-08-06 7:32 ` Christophe Leroy
2021-08-06 13:22 ` Xiongwei Song
2021-08-06 6:53 ` Michael Ellerman
2021-08-06 13:14 ` Xiongwei Song
2021-08-06 14:26 ` Segher Boessenkool
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