Author: vangyzen Date: Fri Jun 12 21:10:45 2020 New Revision: 362119 URL: https://svnweb.freebsd.org/changeset/base/362119
Log: 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 Modified: head/sys/amd64/amd64/fpu.c head/sys/i386/i386/npx.c Modified: head/sys/amd64/amd64/fpu.c ============================================================================== --- head/sys/amd64/amd64/fpu.c Fri Jun 12 20:39:42 2020 (r362118) +++ head/sys/amd64/amd64/fpu.c Fri Jun 12 21:10:45 2020 (r362119) @@ -368,8 +368,18 @@ fpuinitstate(void *arg __unused) register_t saveintr; int cp[4], i, max_ext_n; + /* 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); fpu_initialstate = malloc(cpu_max_ext_state_size, M_DEVBUF, M_WAITOK | M_ZERO); + if (use_xsave) { + max_ext_n = flsl(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(); @@ -399,9 +409,6 @@ fpuinitstate(void *arg __unused) offsetof(struct xstate_hdr, xstate_bv)); *xstate_bv = XFEATURE_ENABLED_X87 | XFEATURE_ENABLED_SSE; - max_ext_n = flsl(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; @@ -415,10 +422,6 @@ fpuinitstate(void *arg __unused) xsave_area_desc[i].size = cp[0]; } } - - 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); Modified: head/sys/i386/i386/npx.c ============================================================================== --- head/sys/i386/i386/npx.c Fri Jun 12 20:39:42 2020 (r362118) +++ head/sys/i386/i386/npx.c Fri Jun 12 21:10:45 2020 (r362119) @@ -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; @@ -541,10 +548,6 @@ npxinitstate(void *arg __unused) xsave_area_desc[i].size = cp[0]; } } - - 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); _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
