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x86: Fix misordered logic for setting rep_movsb_stop_threshold

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Move the setting of `rep_movsb_stop_threshold` to after the tunables
have been collected so that the `rep_movsb_stop_threshold` (which
is used to redirect control flow to the non_temporal case) will
use any user value for `non_temporal_threshold` (set using
glibc.cpu.x86_non_temporal_threshold)
This commit is contained in:
Noah Goldstein 2022-06-14 13:50:11 -07:00
parent 7374c02b68
commit 0355915514
1 changed files with 12 additions and 12 deletions
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24
sysdeps/x86/dl-cacheinfo.h
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@ -898,18 +898,6 @@ dl_init_cacheinfo (struct cpu_features *cpu_features)
if (CPU_FEATURE_USABLE_P (cpu_features, FSRM))
rep_movsb_threshold = 2112;
unsigned long int rep_movsb_stop_threshold;
/* ERMS feature is implemented from AMD Zen3 architecture and it is
performing poorly for data above L2 cache size. Henceforth, adding
an upper bound threshold parameter to limit the usage of Enhanced
REP MOVSB operations and setting its value to L2 cache size. */
if (cpu_features->basic.kind == arch_kind_amd)
rep_movsb_stop_threshold = core;
/* Setting the upper bound of ERMS to the computed value of
non-temporal threshold for architectures other than AMD. */
else
rep_movsb_stop_threshold = non_temporal_threshold;
/* The default threshold to use Enhanced REP STOSB. */
unsigned long int rep_stosb_threshold = 2048;
@ -951,6 +939,18 @@ dl_init_cacheinfo (struct cpu_features *cpu_features)
SIZE_MAX);
#endif
unsigned long int rep_movsb_stop_threshold;
/* ERMS feature is implemented from AMD Zen3 architecture and it is
performing poorly for data above L2 cache size. Henceforth, adding
an upper bound threshold parameter to limit the usage of Enhanced
REP MOVSB operations and setting its value to L2 cache size. */
if (cpu_features->basic.kind == arch_kind_amd)
rep_movsb_stop_threshold = core;
/* Setting the upper bound of ERMS to the computed value of
non-temporal threshold for architectures other than AMD. */
else
rep_movsb_stop_threshold = non_temporal_threshold;
cpu_features->data_cache_size = data;
cpu_features->shared_cache_size = shared;
cpu_features->non_temporal_threshold = non_temporal_threshold;