Commit f7b78602 authored by Peter Maydell's avatar Peter Maydell
Browse files

accel/tcg: Add cluster number to TCG TB hash 



Include the cluster number in the hash we use to look
up TBs. This is important because a TB that is valid
for one cluster at a given physical address and set
of CPU flags is not necessarily valid for another:
the two clusters may have different views of physical
memory, or may have different CPU features (eg FPU
present or absent).

We put the cluster number in the high 8 bits of the
TB cflags. This gives us up to 256 clusters, which should
be enough for anybody. If we ever need more, or need
more bits in cflags for other purposes, we could make
tb_hash_func() take more data (and expand qemu_xxhash7()
to qemu_xxhash8()).

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: default avatarAlistair Francis <alistair.francis@wdc.com>
Reviewed-by: default avatarEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20190121152218.9592-4-peter.maydell@linaro.org
parent 7ea7b9ad

accel/tcg/cpu-exec.c

+3 −0
Original line number Diff line number Diff line
@@ -325,6 +325,9 @@ TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc, 
    struct tb_desc desc;

    uint32_t h;



    cf_mask &= ~CF_CLUSTER_MASK;

    cf_mask |= cpu->cluster_index << CF_CLUSTER_SHIFT;



    desc.env = (CPUArchState *)cpu->env_ptr;

    desc.cs_base = cs_base;

    desc.flags = flags;

accel/tcg/translate-all.c

+3 −0
Original line number Diff line number Diff line
@@ -1688,6 +1688,9 @@ TranslationBlock *tb_gen_code(CPUState *cpu, 
        cflags |= CF_NOCACHE | 1;

    }



    cflags &= ~CF_CLUSTER_MASK;

    cflags |= cpu->cluster_index << CF_CLUSTER_SHIFT;



 buffer_overflow:

    tb = tb_alloc(pc);

    if (unlikely(!tb)) {

include/exec/exec-all.h

+3 −1
Original line number Diff line number Diff line
@@ -351,9 +351,11 @@ struct TranslationBlock { 
#define CF_USE_ICOUNT  0x00020000

#define CF_INVALID     0x00040000 /* TB is stale. Set with @jmp_lock held */

#define CF_PARALLEL    0x00080000 /* Generate code for a parallel context */

#define CF_CLUSTER_MASK 0xff000000 /* Top 8 bits are cluster ID */

#define CF_CLUSTER_SHIFT 24

/* cflags' mask for hashing/comparison */

#define CF_HASH_MASK   \

    (CF_COUNT_MASK | CF_LAST_IO | CF_USE_ICOUNT | CF_PARALLEL)

    (CF_COUNT_MASK | CF_LAST_IO | CF_USE_ICOUNT | CF_PARALLEL | CF_CLUSTER_MASK)



    /* Per-vCPU dynamic tracing state used to generate this TB */

    uint32_t trace_vcpu_dstate;