Message ID | 20171107150558.22131-10-alex.bennee@linaro.org |
---|---|
State | New |
Headers | show |
Series | Initial support for SVE | expand |
On Tue, Nov 07, 2017 at 03:05:57PM +0000, Alex Bennée wrote: > Add the ability to save SVE registers from the signal context. This is > controlled with an optional flag --test-sve. The whole thing is > conditionally compiled when SVE support is in the sigcontext headers. > > Technically SVE registers could be beyond an EXTRA_MAGIC section. I've > not seen this on the model so currently we abort() if we encounter the > EXTRA_MAGIC section. > > Signed-off-by: Alex Bennée <alex.bennee@linaro.org> > --- > risu_reginfo_aarch64.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++ > risu_reginfo_aarch64.h | 8 ++++++ > 2 files changed, 82 insertions(+) > > diff --git a/risu_reginfo_aarch64.c b/risu_reginfo_aarch64.c > index 38ad338..7c97790 100644 > --- a/risu_reginfo_aarch64.c > +++ b/risu_reginfo_aarch64.c > @@ -13,12 +13,78 @@ > #include <stdio.h> > #include <ucontext.h> > #include <string.h> > +#include <getopt.h> > +#include <stdlib.h> > +#include <stdbool.h> > > #include "risu.h" > #include "risu_reginfo_aarch64.h" > > +#ifndef SVE_MAGIC > void *arch_long_opts; > char *arch_extra_help; > +#else > +/* Should we test SVE register state */ > +static int test_sve; > +static struct option extra_opts[] = { > + {"test-sve", no_argument, &test_sve, 1}, > + {0, 0, 0, 0} > +}; > + > +void *arch_long_opts = &extra_opts[0]; > +char *arch_extra_help = " --test-sve Compare SVE registers\n"; > + > +/* Extra SVE copy function, only called with --test-sve */ > +static void reginfo_copy_sve(struct reginfo *ri, struct _aarch64_ctx *ctx) > +{ > + struct sve_context *sve; > + int r, vq; > + bool found = false; > + > + while (!found) { > + switch (ctx->magic) > + { > + case SVE_MAGIC: > + found = true; > + break; > + case EXTRA_MAGIC: > + fprintf(stderr, "%s: found EXTRA_MAGIC\n", __func__); > + abort(); > + case 0: > + /* We might not have an SVE context */ > + fprintf(stderr, "%s: reached end of ctx, no joy (%d)\n", __func__, ctx->size); > + return; > + default: > + ctx = (struct _aarch64_ctx *)((void *)ctx + ctx->size); > + break; > + } > + > + } > + > + sve = (struct sve_context *) ctx; > + ri->vl = sve->vl; > + vq = sve_vq_from_vl(sve->vl); /* number of quads for whole vl */ > + > + /* Copy ZREG's one at a time */ > + for (r = 0; r < SVE_NUM_ZREGS; r++) { > + memcpy(&ri->zregs[r], > + (char *)sve + SVE_SIG_ZREG_OFFSET(vq, r), > + SVE_SIG_ZREG_SIZE(vq)); > + } > + > + /* Copy PREG's one at a time */ > + for (r = 0; r < SVE_NUM_PREGS; r++) { > + memcpy(&ri->pregs[r], > + (char *)sve + SVE_SIG_PREG_OFFSET(vq, r), > + SVE_SIG_PREG_SIZE(vq)); > + } > + > + /* Finally the FFR */ > + memcpy(&ri->ffr,(char *)sve + SVE_SIG_FFR_OFFSET(vq), > + SVE_SIG_FFR_SIZE(vq)); > + > +} > +#endif > > /* reginfo_init: initialize with a ucontext */ > void reginfo_init(struct reginfo *ri, ucontext_t *uc) > @@ -26,6 +92,7 @@ void reginfo_init(struct reginfo *ri, ucontext_t *uc) > int i; > struct _aarch64_ctx *ctx; > struct fpsimd_context *fp; > + > /* necessary to be able to compare with memcmp later */ > memset(ri, 0, sizeof(*ri)); > > @@ -59,6 +126,13 @@ void reginfo_init(struct reginfo *ri, ucontext_t *uc) > for (i = 0; i < 32; i++) { > ri->vregs[i] = fp->vregs[i]; > } > + Where do you get uc from? If it comes straight out of a signal frame that's OK, but if it's copied around as a ucontext_t or manipulated by getcontext() etc this is going to go wrong when extra_context is present. This code may get used by people as a reference, so at least adding a comment to the effect that this only works on the signal frame would be a good idea. When you add support for extra_context, you should probably add a sanity-check to ensure that the datap pointer really does point to the right place -- see <asm/sigcontext.h>. Even though the kernel _should_ never violate this, it can be violated by ucontext_t manipulation in userspace, so any function that doesn't know where its ucontext_t came from should do this check. [...] Cheers ---Dave
diff --git a/risu_reginfo_aarch64.c b/risu_reginfo_aarch64.c index 38ad338..7c97790 100644 --- a/risu_reginfo_aarch64.c +++ b/risu_reginfo_aarch64.c @@ -13,12 +13,78 @@ #include <stdio.h> #include <ucontext.h> #include <string.h> +#include <getopt.h> +#include <stdlib.h> +#include <stdbool.h> #include "risu.h" #include "risu_reginfo_aarch64.h" +#ifndef SVE_MAGIC void *arch_long_opts; char *arch_extra_help; +#else +/* Should we test SVE register state */ +static int test_sve; +static struct option extra_opts[] = { + {"test-sve", no_argument, &test_sve, 1}, + {0, 0, 0, 0} +}; + +void *arch_long_opts = &extra_opts[0]; +char *arch_extra_help = " --test-sve Compare SVE registers\n"; + +/* Extra SVE copy function, only called with --test-sve */ +static void reginfo_copy_sve(struct reginfo *ri, struct _aarch64_ctx *ctx) +{ + struct sve_context *sve; + int r, vq; + bool found = false; + + while (!found) { + switch (ctx->magic) + { + case SVE_MAGIC: + found = true; + break; + case EXTRA_MAGIC: + fprintf(stderr, "%s: found EXTRA_MAGIC\n", __func__); + abort(); + case 0: + /* We might not have an SVE context */ + fprintf(stderr, "%s: reached end of ctx, no joy (%d)\n", __func__, ctx->size); + return; + default: + ctx = (struct _aarch64_ctx *)((void *)ctx + ctx->size); + break; + } + + } + + sve = (struct sve_context *) ctx; + ri->vl = sve->vl; + vq = sve_vq_from_vl(sve->vl); /* number of quads for whole vl */ + + /* Copy ZREG's one at a time */ + for (r = 0; r < SVE_NUM_ZREGS; r++) { + memcpy(&ri->zregs[r], + (char *)sve + SVE_SIG_ZREG_OFFSET(vq, r), + SVE_SIG_ZREG_SIZE(vq)); + } + + /* Copy PREG's one at a time */ + for (r = 0; r < SVE_NUM_PREGS; r++) { + memcpy(&ri->pregs[r], + (char *)sve + SVE_SIG_PREG_OFFSET(vq, r), + SVE_SIG_PREG_SIZE(vq)); + } + + /* Finally the FFR */ + memcpy(&ri->ffr,(char *)sve + SVE_SIG_FFR_OFFSET(vq), + SVE_SIG_FFR_SIZE(vq)); + +} +#endif /* reginfo_init: initialize with a ucontext */ void reginfo_init(struct reginfo *ri, ucontext_t *uc) @@ -26,6 +92,7 @@ void reginfo_init(struct reginfo *ri, ucontext_t *uc) int i; struct _aarch64_ctx *ctx; struct fpsimd_context *fp; + /* necessary to be able to compare with memcmp later */ memset(ri, 0, sizeof(*ri)); @@ -59,6 +126,13 @@ void reginfo_init(struct reginfo *ri, ucontext_t *uc) for (i = 0; i < 32; i++) { ri->vregs[i] = fp->vregs[i]; } + +#ifdef SVE_MAGIC + if (test_sve) { + ctx = (struct _aarch64_ctx *) &uc->uc_mcontext.__reserved[0]; + reginfo_copy_sve(ri, ctx); + } +#endif }; /* reginfo_is_eq: compare the reginfo structs, returns nonzero if equal */ diff --git a/risu_reginfo_aarch64.h b/risu_reginfo_aarch64.h index a05fb4e..317383f 100644 --- a/risu_reginfo_aarch64.h +++ b/risu_reginfo_aarch64.h @@ -25,6 +25,14 @@ struct reginfo { uint32_t fpsr; uint32_t fpcr; __uint128_t vregs[32]; + +#ifdef SVE_MAGIC + /* SVE */ + uint16_t vl; /* current VL */ + __uint128_t zregs[SVE_NUM_ZREGS][SVE_VQ_MAX]; + uint16_t pregs[SVE_NUM_PREGS][SVE_VQ_MAX]; + uint16_t ffr[SVE_VQ_MAX]; +#endif }; #endif /* RISU_REGINFO_AARCH64_H */
Add the ability to save SVE registers from the signal context. This is controlled with an optional flag --test-sve. The whole thing is conditionally compiled when SVE support is in the sigcontext headers. Technically SVE registers could be beyond an EXTRA_MAGIC section. I've not seen this on the model so currently we abort() if we encounter the EXTRA_MAGIC section. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> --- risu_reginfo_aarch64.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++ risu_reginfo_aarch64.h | 8 ++++++ 2 files changed, 82 insertions(+) -- 2.14.2