From a72c71b77d73f9888cbe8da8be09d7097ebca64f Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Tue, 11 Aug 2020 12:32:35 -0300 Subject: [PATCH] target/ppc: Integrate icount to purr, vtb, and tbu40 Currently if option '-icount auto' is passed to the QEMU TCG to enable counting instructions the VM crashes with the following error report when Linux runs on it: qemu-system-ppc64: Bad icount read This happens because read/write access to the SPRs PURR, VTB, and TBU40 is not integrated to the icount framework. This commit fixes that issue by making the read/write access of these SPRs aware of icount framework, adding the proper gen_io_start() calls before calling the helpers to load/store these SPRs in TCG and ensuring that the associated TBs end immediately after, accordingly to what's in docs/devel/tcg-icount.rst. Signed-off-by: Gustavo Romero Message-Id: <20200811153235.4527-1-gromero@linux.ibm.com> Reviewed-by: Richard Henderson Signed-off-by: David Gibson --- target/ppc/translate_init.inc.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/target/ppc/translate_init.inc.c b/target/ppc/translate_init.inc.c index 5134123dd6..230a062d29 100644 --- a/target/ppc/translate_init.inc.c +++ b/target/ppc/translate_init.inc.c @@ -284,12 +284,24 @@ static void spr_write_atbu(DisasContext *ctx, int sprn, int gprn) ATTRIBUTE_UNUSED static void spr_read_purr(DisasContext *ctx, int gprn, int sprn) { + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_io_start(); + } gen_helper_load_purr(cpu_gpr[gprn], cpu_env); + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_stop_exception(ctx); + } } static void spr_write_purr(DisasContext *ctx, int sprn, int gprn) { + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_io_start(); + } gen_helper_store_purr(cpu_env, cpu_gpr[gprn]); + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_stop_exception(ctx); + } } /* HDECR */ @@ -319,17 +331,35 @@ static void spr_write_hdecr(DisasContext *ctx, int sprn, int gprn) static void spr_read_vtb(DisasContext *ctx, int gprn, int sprn) { + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_io_start(); + } gen_helper_load_vtb(cpu_gpr[gprn], cpu_env); + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_stop_exception(ctx); + } } static void spr_write_vtb(DisasContext *ctx, int sprn, int gprn) { + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_io_start(); + } gen_helper_store_vtb(cpu_env, cpu_gpr[gprn]); + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_stop_exception(ctx); + } } static void spr_write_tbu40(DisasContext *ctx, int sprn, int gprn) { + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_io_start(); + } gen_helper_store_tbu40(cpu_env, cpu_gpr[gprn]); + if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) { + gen_stop_exception(ctx); + } } #endif