From: Nicholas Piggin <npiggin@gmail.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail.com>
Subject: [RFC PATCH 04/19] powerpc/pseries: hvcall stack frame overhead
Date: Mon, 31 Oct 2022 15:54:25 +1000 [thread overview]
Message-ID: <20221031055440.3594315-5-npiggin@gmail.com> (raw)
In-Reply-To: <20221031055440.3594315-1-npiggin@gmail.com>
This call may use the min size stack frame. The scratch space used is
in the caller's parameter area frame, not this function's frame.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/platforms/pseries/hvCall.S | 38 +++++++++++++------------
1 file changed, 20 insertions(+), 18 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 762eb15d3bd4..783c16ad648b 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -27,7 +27,9 @@ hcall_tracepoint_refcount:
/*
* precall must preserve all registers. use unused STK_PARAM()
- * areas to save snapshots and opcode.
+ * areas to save snapshots and opcode. STK_PARAM() in the caller's
+ * frame will be available even on ELFv2 because these are all
+ * variadic functions.
*/
#define HCALL_INST_PRECALL(FIRST_REG) \
mflr r0; \
@@ -41,29 +43,29 @@ hcall_tracepoint_refcount:
std r10,STK_PARAM(R10)(r1); \
std r0,16(r1); \
addi r4,r1,STK_PARAM(FIRST_REG); \
- stdu r1,-STACK_FRAME_OVERHEAD(r1); \
+ stdu r1,-STACK_FRAME_MIN_SIZE(r1); \
bl __trace_hcall_entry; \
- ld r3,STACK_FRAME_OVERHEAD+STK_PARAM(R3)(r1); \
- ld r4,STACK_FRAME_OVERHEAD+STK_PARAM(R4)(r1); \
- ld r5,STACK_FRAME_OVERHEAD+STK_PARAM(R5)(r1); \
- ld r6,STACK_FRAME_OVERHEAD+STK_PARAM(R6)(r1); \
- ld r7,STACK_FRAME_OVERHEAD+STK_PARAM(R7)(r1); \
- ld r8,STACK_FRAME_OVERHEAD+STK_PARAM(R8)(r1); \
- ld r9,STACK_FRAME_OVERHEAD+STK_PARAM(R9)(r1); \
- ld r10,STACK_FRAME_OVERHEAD+STK_PARAM(R10)(r1)
+ ld r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1); \
+ ld r4,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1); \
+ ld r5,STACK_FRAME_MIN_SIZE+STK_PARAM(R5)(r1); \
+ ld r6,STACK_FRAME_MIN_SIZE+STK_PARAM(R6)(r1); \
+ ld r7,STACK_FRAME_MIN_SIZE+STK_PARAM(R7)(r1); \
+ ld r8,STACK_FRAME_MIN_SIZE+STK_PARAM(R8)(r1); \
+ ld r9,STACK_FRAME_MIN_SIZE+STK_PARAM(R9)(r1); \
+ ld r10,STACK_FRAME_MIN_SIZE+STK_PARAM(R10)(r1)
/*
* postcall is performed immediately before function return which
* allows liberal use of volatile registers.
*/
#define __HCALL_INST_POSTCALL \
- ld r0,STACK_FRAME_OVERHEAD+STK_PARAM(R3)(r1); \
- std r3,STACK_FRAME_OVERHEAD+STK_PARAM(R3)(r1); \
+ ld r0,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1); \
+ std r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1); \
mr r4,r3; \
mr r3,r0; \
bl __trace_hcall_exit; \
- ld r0,STACK_FRAME_OVERHEAD+16(r1); \
- addi r1,r1,STACK_FRAME_OVERHEAD; \
+ ld r0,STACK_FRAME_MIN_SIZE+16(r1); \
+ addi r1,r1,STACK_FRAME_MIN_SIZE; \
ld r3,STK_PARAM(R3)(r1); \
mtlr r0
@@ -303,14 +305,14 @@ plpar_hcall9_trace:
mr r7,r8
mr r8,r9
mr r9,r10
- ld r10,STACK_FRAME_OVERHEAD+STK_PARAM(R11)(r1)
- ld r11,STACK_FRAME_OVERHEAD+STK_PARAM(R12)(r1)
- ld r12,STACK_FRAME_OVERHEAD+STK_PARAM(R13)(r1)
+ ld r10,STACK_FRAME_MIN_SIZE+STK_PARAM(R11)(r1)
+ ld r11,STACK_FRAME_MIN_SIZE+STK_PARAM(R12)(r1)
+ ld r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R13)(r1)
HVSC
mr r0,r12
- ld r12,STACK_FRAME_OVERHEAD+STK_PARAM(R4)(r1)
+ ld r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1)
std r4,0(r12)
std r5,8(r12)
std r6,16(r12)
--
2.37.2
next prev parent reply other threads:[~2022-10-31 5:59 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-31 5:54 [RFC PATCH 00/19] Remove STACK_FRAME_OVERHEAD Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 01/19] powerpc/perf: callchain validate kernel stack pointer bounds Nicholas Piggin
2022-11-04 13:10 ` Segher Boessenkool
2022-10-31 5:54 ` [RFC PATCH 02/19] powerpc: Rearrange copy_thread child stack creation Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 03/19] powerpc/64: Remove asm interrupt tracing call helpers Nicholas Piggin
2022-10-31 5:54 ` Nicholas Piggin [this message]
2022-10-31 5:54 ` [RFC PATCH 05/19] powerpc/32: Use load and store multiple in GPR save/restore macros Nicholas Piggin
2022-11-03 8:26 ` Christophe Leroy
2022-11-07 12:45 ` Nicholas Piggin
2022-11-07 12:51 ` Christophe Leroy
2022-10-31 5:54 ` [RFC PATCH 06/19] powerpc: simplify ppc_save_regs Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 07/19] powerpc: add definition for pt_regs offset within an interrupt frame Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 08/19] powerpc: add a definition for the marker offset within the " Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 09/19] powerpc: Rename STACK_FRAME_MARKER and derive it from frame offset Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 10/19] powerpc: add a define for the user interrupt frame size Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 11/19] powerpc: add a define for the switch frame size and regs offset Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 12/19] powerpc: copy_thread fill in interrupt frame marker and back chain Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 13/19] powerpc: copy_thread add a back chain to the switch stack frame Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 14/19] powerpc: split validate_sp into two functions Nicholas Piggin
2022-11-07 0:58 ` Russell Currey
2022-11-07 12:29 ` Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 15/19] powerpc: allow minimum sized kernel stack frames Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 16/19] powerpc/64: ELFv2 use minimal stack frames in int and switch frame sizes Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 17/19] powerpc: remove STACK_FRAME_OVERHEAD Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 18/19] powerpc: change stack marker memory operations to 32-bit Nicholas Piggin
2022-10-31 5:54 ` [RFC PATCH 19/19] powerpc/64: ELFv2 use reserved word in the stack frame for the regs marker 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=20221031055440.3594315-5-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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.