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| author | Jamie Iles <jamie@jamieiles.com> | 2022-11-15 20:08:30 +0000 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2022-12-02 10:04:36 -0800 |
| commit | 3bd7743f8d6d7171db9897a746038eefd52a1fbd (patch) | |
| tree | d97eaaebb148a38ef8900c4a1a58f0177c667ad4 /arch/riscv/kernel | |
| parent | 8a6841c439dfbba2067a533b0e8264ea438689f6 (diff) | |
| download | linux-3bd7743f8d6d7171db9897a746038eefd52a1fbd.tar.bz2 | |
RISC-V: reduce mcount save space on RV32
For RV32 we can reduce the size of the ABI save+restore state by using
SZREG so that register stores are packed rather than on an 8 byte
boundary.
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20221115200832.706370-3-jamie@jamieiles.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kernel')
| -rw-r--r-- | arch/riscv/kernel/mcount.S | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/arch/riscv/kernel/mcount.S b/arch/riscv/kernel/mcount.S index 9cf0904afd6d..613bd07c6268 100644 --- a/arch/riscv/kernel/mcount.S +++ b/arch/riscv/kernel/mcount.S @@ -15,8 +15,8 @@ .macro SAVE_ABI_STATE addi sp, sp, -16 - REG_S s0, 0(sp) - REG_S ra, 8(sp) + REG_S s0, 0*SZREG(sp) + REG_S ra, 1*SZREG(sp) addi s0, sp, 16 .endm @@ -25,24 +25,24 @@ * register if a0 was not saved. */ .macro SAVE_RET_ABI_STATE - addi sp, sp, -32 - REG_S s0, 16(sp) - REG_S ra, 24(sp) - REG_S a0, 8(sp) - addi s0, sp, 32 + addi sp, sp, -4*SZREG + REG_S s0, 2*SZREG(sp) + REG_S ra, 3*SZREG(sp) + REG_S a0, 1*SZREG(sp) + addi s0, sp, 4*SZREG .endm .macro RESTORE_ABI_STATE - REG_L ra, 8(sp) - REG_L s0, 0(sp) + REG_L ra, 1*SZREG(sp) + REG_L s0, 0*SZREG(sp) addi sp, sp, 16 .endm .macro RESTORE_RET_ABI_STATE - REG_L ra, 24(sp) - REG_L s0, 16(sp) - REG_L a0, 8(sp) - addi sp, sp, 32 + REG_L ra, 3*SZREG(sp) + REG_L s0, 2*SZREG(sp) + REG_L a0, 1*SZREG(sp) + addi sp, sp, 4*SZREG .endm ENTRY(ftrace_stub) @@ -101,10 +101,10 @@ ENTRY(MCOUNT_NAME) * prepare_to_return(&ra_to_caller_of_caller, ra_to_caller) */ do_ftrace_graph_caller: - addi a0, s0, -8 + addi a0, s0, -SZREG mv a1, ra #ifdef HAVE_FUNCTION_GRAPH_FP_TEST - REG_L a2, -16(s0) + REG_L a2, -2*SZREG(s0) #endif SAVE_ABI_STATE call prepare_ftrace_return @@ -117,7 +117,7 @@ do_ftrace_graph_caller: * (*ftrace_trace_function)(ra_to_caller, ra_to_caller_of_caller) */ do_trace: - REG_L a1, -8(s0) + REG_L a1, -SZREG(s0) mv a0, ra SAVE_ABI_STATE |