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
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