From: Nicholas Piggin <npiggin@gmail.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail.com>
Subject: [PATCH 2/9] powerpc/64s: SLB miss handler avoid saving faulting address into EX_DAR
Date: Sun, 21 May 2017 23:15:43 +1000 [thread overview]
Message-ID: <20170521131550.25813-3-npiggin@gmail.com> (raw)
In-Reply-To: <20170521131550.25813-1-npiggin@gmail.com>
The EX_DAR save area is only used in exceptional cases. With r3 no
longer clobbered by slb_allocate_realmode, saving faulting address to
EX_DAR can be deferred to those cases.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/kernel/exceptions-64s.S | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index ae418b85c17c..a4a71bce35d6 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -628,7 +628,6 @@ EXC_COMMON_BEGIN(slb_miss_realmode)
stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
- std r3,PACA_EXSLB+EX_DAR(r13)
crset 4*cr0+eq
#ifdef CONFIG_PPC_STD_MMU_64
@@ -638,11 +637,10 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
#endif
ld r10,PACA_EXSLB+EX_LR(r13)
- ld r3,PACA_EXSLB+EX_R3(r13)
lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
mtlr r10
- beq 8f /* if bad address, make full stack frame */
+ beq- 8f /* if bad address, make full stack frame */
andi. r10,r12,MSR_RI /* check for unrecoverable exception */
beq- 2f
@@ -657,6 +655,7 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
.machine pop
RESTORE_PPR_PACA(PACA_EXSLB, r9)
+ ld r3,PACA_EXSLB+EX_R3(r13)
ld r9,PACA_EXSLB+EX_R9(r13)
ld r10,PACA_EXSLB+EX_R10(r13)
ld r11,PACA_EXSLB+EX_R11(r13)
@@ -665,7 +664,9 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
rfid
b . /* prevent speculative execution */
-2: mfspr r11,SPRN_SRR0
+2: std r3,PACA_EXSLB+EX_DAR(r13)
+ ld r3,PACA_EXSLB+EX_R3(r13)
+ mfspr r11,SPRN_SRR0
LOAD_HANDLER(r10,unrecov_slb)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
@@ -673,7 +674,9 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
rfid
b .
-8: mfspr r11,SPRN_SRR0
+8: std r3,PACA_EXSLB+EX_DAR(r13)
+ ld r3,PACA_EXSLB+EX_R3(r13)
+ mfspr r11,SPRN_SRR0
LOAD_HANDLER(r10,bad_addr_slb)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
--
2.11.0
next prev parent reply other threads:[~2017-05-21 13:16 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-05-21 13:15 [PATCH 0/9] Reduce PACA save areas Nicholas Piggin
2017-05-21 13:15 ` [PATCH 1/9] powerpc/64s: slb_allocate_realmode() preserve r3 Nicholas Piggin
2017-06-22 13:12 ` [1/9] " Michael Ellerman
2017-05-21 13:15 ` Nicholas Piggin [this message]
2017-05-21 13:15 ` [PATCH 3/9] powerpc/64s: SLB miss already has CTR saved for relocatable kernel Nicholas Piggin
2017-06-19 11:45 ` Michael Ellerman
2017-06-19 17:20 ` Nicholas Piggin
2017-05-21 13:15 ` [PATCH 4/9] powerpc/64s: SLB miss handler avoid r3 save/restore Nicholas Piggin
2017-06-19 4:48 ` Michael Ellerman
2017-06-19 16:54 ` Nicholas Piggin
2017-05-21 13:15 ` [PATCH 5/9] powerpc/64s: paca add EX_SIZE definition for exception save areas Nicholas Piggin
2017-05-21 13:15 ` [PATCH 6/9] powerpc/64s: paca EX_SRR0 is unused, remove it Nicholas Piggin
2017-05-21 13:15 ` [PATCH 7/9] powerpc/64s: paca EX_LR can be merged with EX_DAR Nicholas Piggin
2017-05-21 13:15 ` [PATCH 8/9] powerpc/64s: paca EX_R3 " Nicholas Piggin
2017-05-21 13:15 ` [PATCH 9/9] powerpc/64s: paca EX_CTR is not used with !RELOCATABLE, remove it Nicholas Piggin
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=20170521131550.25813-3-npiggin@gmail.com \
--to=npiggin@gmail.com \
--cc=linuxppc-dev@lists.ozlabs.org \
/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;
as well as URLs for NNTP newsgroup(s).