diff options
| author | bellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162> | 2006-05-02 22:18:28 +0000 |
|---|---|---|
| committer | bellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162> | 2006-05-02 22:18:28 +0000 |
| commit | f5d2a381d1fb5f7def1c86c95d0c093e54e3aa67 (patch) | |
| tree | 3dcda05b2803be4e205a4eeda5a2c3f372a6dbf5 /hw/mips_r4k.c | |
| parent | e553272d759b41e6d1de226c8fad0aab56fefdd6 (diff) | |
| download | focaccia-qemu-f5d2a381d1fb5f7def1c86c95d0c093e54e3aa67.tar.gz focaccia-qemu-f5d2a381d1fb5f7def1c86c95d0c093e54e3aa67.zip | |
performance boost (on P4 hosts at least, rdtsc is a _very_ bad random generator)
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1892 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'hw/mips_r4k.c')
| -rw-r--r-- | hw/mips_r4k.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/hw/mips_r4k.c b/hw/mips_r4k.c index 6b6b6cb33b..0cb11683ae 100644 --- a/hw/mips_r4k.c +++ b/hw/mips_r4k.c @@ -27,11 +27,14 @@ void cpu_mips_irqctrl_init (void) { } +/* XXX: do not use a global */ uint32_t cpu_mips_get_random (CPUState *env) { - uint32_t now = qemu_get_clock(vm_clock); - - return now % (MIPS_TLB_NB - env->CP0_Wired) + env->CP0_Wired; + static uint32_t seed = 0; + uint32_t idx; + seed = seed * 314159 + 1; + idx = (seed >> 16) % (MIPS_TLB_NB - env->CP0_Wired) + env->CP0_Wired; + return idx; } /* MIPS R4K timer */ |