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| author | Eric van Gyzen <vangyzen@FreeBSD.org> | 2020-06-12 21:10:45 +0000 |
|---|---|---|
| committer | Eric van Gyzen <vangyzen@FreeBSD.org> | 2020-06-12 21:10:45 +0000 |
| commit | 674cbe79086dd950e0df39dbb2d211af0b4c54f1 (patch) | |
| tree | 0d30d49eb2c739b82399974bd0cee6928f22a3de /sys/i386 | |
| parent | f092a3c71c314592f996a809c8cc40f21be50065 (diff) | |
| download | src-674cbe79086dd950e0df39dbb2d211af0b4c54f1.tar.gz src-674cbe79086dd950e0df39dbb2d211af0b4c54f1.zip | |
FPU init: Do potentially blocking operations before disabling interrupts
In particular, uma_zcreate creates sysctl oids, which locks an sx lock,
which uses IPIs under contention. IPIs tend not to work very well
when interrupts are disabled. Who knew, right?
Reviewed by: cem kib
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D25098
Notes
Notes:
svn path=/head/; revision=362119
Diffstat (limited to 'sys/i386')
| -rw-r--r-- | sys/i386/i386/npx.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/sys/i386/i386/npx.c b/sys/i386/i386/npx.c index 7c3496575199..fc03de27d407 100644 --- a/sys/i386/i386/npx.c +++ b/sys/i386/i386/npx.c @@ -479,8 +479,21 @@ npxinitstate(void *arg __unused) if (!hw_float) return; + /* Do potentially blocking operations before disabling interrupts. */ + fpu_save_area_zone = uma_zcreate("FPU_save_area", + cpu_max_ext_state_size, NULL, NULL, NULL, NULL, + XSAVE_AREA_ALIGN - 1, 0); npx_initialstate = malloc(cpu_max_ext_state_size, M_DEVBUF, M_WAITOK | M_ZERO); + if (use_xsave) { + if (xsave_mask >> 32 != 0) + max_ext_n = fls(xsave_mask >> 32) + 32; + else + max_ext_n = fls(xsave_mask); + xsave_area_desc = malloc(max_ext_n * sizeof(struct + xsave_area_elm_descr), M_DEVBUF, M_WAITOK | M_ZERO); + } + saveintr = intr_disable(); stop_emulating(); @@ -522,12 +535,6 @@ npxinitstate(void *arg __unused) offsetof(struct xstate_hdr, xstate_bv)); *xstate_bv = XFEATURE_ENABLED_X87 | XFEATURE_ENABLED_SSE; - if (xsave_mask >> 32 != 0) - max_ext_n = fls(xsave_mask >> 32) + 32; - else - max_ext_n = fls(xsave_mask); - xsave_area_desc = malloc(max_ext_n * sizeof(struct - xsave_area_elm_descr), M_DEVBUF, M_WAITOK | M_ZERO); /* x87 state */ xsave_area_desc[0].offset = 0; xsave_area_desc[0].size = 160; @@ -542,10 +549,6 @@ npxinitstate(void *arg __unused) } } - fpu_save_area_zone = uma_zcreate("FPU_save_area", - cpu_max_ext_state_size, NULL, NULL, NULL, NULL, - XSAVE_AREA_ALIGN - 1, 0); - start_emulating(); intr_restore(saveintr); } |