6984eff3c5
- fix precision when one convert to seconds and then multiply we can have precision errors for example if one have 77ms, it will go to 0 when converted to seconds and then multiply that 0 by 1000 will return 0 instead of 77ms. - fix mismatch nsec/usec nsec was multiplied by 1000*1000 while usec by 1000*1000*1000 it should be the opposite. anyway the implementation had changed. - implementation description * env_ticks_to_msec: j / (tick_hz / 1000) this is exactly the same as (j * 1000) / tick_hz (eq #2). but this implementation (eq #2) can only handle 54b in j (before overflowing) because of the multiplication by 1000 (10b). with the correct implementation we use all 64b in j. we assume that tick_hz will be prefectly divisible by 1000 so we are ok. * env_ticks_to_usec: j / (tick_hz / (1000 * 1000)) same as in msec case, we use all 64b in j. here we assume that tick_hz is perfectly divisible by (1000 * 1000) i.e. we assume that CPU frequency is some multiple of 1MHz. * env_ticks_to_nsec: (j * 1000) / (tick_hz / (1000 * 1000)) in this case we can't assume that tick_hz is divisible by 10^9 because there are many CPUs with 2.8GHz or 3.3GHz for example. so we multiply j by 1000 this means that we can only handle correctly j up to 54b. (64b - 10b, 10b for the *1000 operation) Signed-off-by: Amir Haroush <amir.haroush@huawei.com> Signed-off-by: Shai Fultheim <shai.fultheim@huawei.com> Change-Id: Ia8ea7f88b718df206fa0731e3f39f419ee922aa7 Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/17078 Community-CI: Mellanox Build Bot Tested-by: SPDK CI Jenkins <sys_sgci@intel.com> Reviewed-by: Jim Harris <james.r.harris@intel.com> Reviewed-by: Ben Walker <benjamin.walker@intel.com> |
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| .. | ||
| .gitignore | ||
| Makefile | ||
| mpool.c | ||
| mpool.h | ||
| ocf_env_headers.h | ||
| ocf_env_list.h | ||
| ocf_env.c | ||
| ocf_env.h | ||