diff options
author | Sandipan Das <sandipan@linux.vnet.ibm.com> | 2017-09-02 00:23:01 +0530 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-11-06 16:48:16 +1100 |
commit | ac0761ebcb08830d8f64b9181f6736b1a00bf746 (patch) | |
tree | 87486f365174fa650334fc56d948f52d3a48affb /arch/powerpc/net/bpf_jit_comp64.c | |
parent | 632f0574167ad3f5d646dad6af87d976a703d93e (diff) | |
download | linux-ac0761ebcb08830d8f64b9181f6736b1a00bf746.tar.bz2 |
bpf: take advantage of stack_depth tracking in powerpc JIT
Take advantage of stack_depth tracking, originally introduced for
x64, in powerpc JIT as well. Round up allocated stack by 16 bytes
to make sure it stays aligned for functions called from JITed bpf
program.
Signed-off-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/net/bpf_jit_comp64.c')
-rw-r--r-- | arch/powerpc/net/bpf_jit_comp64.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index a66e64b0b251..46d74e81aff1 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -69,7 +69,7 @@ static inline bool bpf_has_stack_frame(struct codegen_context *ctx) static int bpf_jit_stack_local(struct codegen_context *ctx) { if (bpf_has_stack_frame(ctx)) - return STACK_FRAME_MIN_SIZE + MAX_BPF_STACK; + return STACK_FRAME_MIN_SIZE + ctx->stack_size; else return -(BPF_PPC_STACK_SAVE + 16); } @@ -82,8 +82,9 @@ static int bpf_jit_stack_tailcallcnt(struct codegen_context *ctx) static int bpf_jit_stack_offsetof(struct codegen_context *ctx, int reg) { if (reg >= BPF_PPC_NVR_MIN && reg < 32) - return (bpf_has_stack_frame(ctx) ? BPF_PPC_STACKFRAME : 0) - - (8 * (32 - reg)); + return (bpf_has_stack_frame(ctx) ? + (BPF_PPC_STACKFRAME + ctx->stack_size) : 0) + - (8 * (32 - reg)); pr_err("BPF JIT is asking about unknown registers"); BUG(); @@ -134,7 +135,7 @@ static void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx) PPC_BPF_STL(0, 1, PPC_LR_STKOFF); } - PPC_BPF_STLU(1, 1, -BPF_PPC_STACKFRAME); + PPC_BPF_STLU(1, 1, -(BPF_PPC_STACKFRAME + ctx->stack_size)); } /* @@ -161,7 +162,7 @@ static void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx) /* Setup frame pointer to point to the bpf stack area */ if (bpf_is_seen_register(ctx, BPF_REG_FP)) PPC_ADDI(b2p[BPF_REG_FP], 1, - STACK_FRAME_MIN_SIZE + MAX_BPF_STACK); + STACK_FRAME_MIN_SIZE + ctx->stack_size); } static void bpf_jit_emit_common_epilogue(u32 *image, struct codegen_context *ctx) @@ -183,7 +184,7 @@ static void bpf_jit_emit_common_epilogue(u32 *image, struct codegen_context *ctx /* Tear down our stack frame */ if (bpf_has_stack_frame(ctx)) { - PPC_ADDI(1, 1, BPF_PPC_STACKFRAME); + PPC_ADDI(1, 1, BPF_PPC_STACKFRAME + ctx->stack_size); if (ctx->seen & SEEN_FUNC) { PPC_BPF_LL(0, 1, PPC_LR_STKOFF); PPC_MTLR(0); @@ -1013,6 +1014,9 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) memset(&cgctx, 0, sizeof(struct codegen_context)); + /* Make sure that the stack is quadword aligned. */ + cgctx.stack_size = round_up(fp->aux->stack_depth, 16); + /* Scouting faux-generate pass 0 */ if (bpf_jit_build_body(fp, 0, &cgctx, addrs)) { /* We hit something illegal or unsupported. */ |