From ec09f877532210e28e1d4b6b12896d3eb6d8e8d1 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Thu, 21 Jun 2018 16:02:54 +0100 Subject: [PATCH] trace: forbid floating point types MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Only one existing trace event uses a floating point type. Unfortunately float and double cannot be supported since SystemTap does not have floating point types. Remove float and double from the whitelist and document this limitation. Update the migrate_transferred trace event to use uint64_t instead of double. Cc: Dr. David Alan Gilbert Cc: Daniel P. Berrangé Cc: Peter Maydell Signed-off-by: Stefan Hajnoczi Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Juan Quintela Message-id: 20180621150254.4922-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi --- docs/devel/tracing.txt | 5 +++++ migration/trace-events | 2 +- qapi/trace-events | 2 +- scripts/tracetool/__init__.py | 2 -- 4 files changed, 7 insertions(+), 4 deletions(-) diff --git a/docs/devel/tracing.txt b/docs/devel/tracing.txt index 07abbb345c..6f815ecbd7 100644 --- a/docs/devel/tracing.txt +++ b/docs/devel/tracing.txt @@ -104,6 +104,11 @@ Trace events should use types as follows: * For everything else, use primitive scalar types (char, int, long) with the appropriate signedness. + * Avoid floating point types (float and double) because SystemTap does not + support them. In most cases it is possible to round to an integer type + instead. This may require scaling the value first by multiplying it by 1000 + or the like when digits after the decimal point need to be preserved. + Format strings should reflect the types defined in the trace event. Take special care to use PRId64 and PRIu64 for int64_t and uint64_t types, respectively. This ensures portability between 32- and 64-bit platforms. diff --git a/migration/trace-events b/migration/trace-events index 3f67758893..7ea522e453 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -133,7 +133,7 @@ migrate_global_state_post_load(const char *state) "loaded state: %s" migrate_global_state_pre_save(const char *state) "saved state: %s" migration_thread_low_pending(uint64_t pending) "%" PRIu64 migrate_state_too_big(void) "" -migrate_transferred(uint64_t tranferred, uint64_t time_spent, double bandwidth, uint64_t size) "transferred %" PRIu64 " time_spent %" PRIu64 " bandwidth %g max_size %" PRId64 +migrate_transferred(uint64_t tranferred, uint64_t time_spent, uint64_t bandwidth, uint64_t size) "transferred %" PRIu64 " time_spent %" PRIu64 " bandwidth %" PRIu64 " max_size %" PRId64 process_incoming_migration_co_end(int ret, int ps) "ret=%d postcopy-state=%d" process_incoming_migration_co_postcopy_end_main(void) "" migration_set_incoming_channel(void *ioc, const char *ioctype) "ioc=%p ioctype=%s" diff --git a/qapi/trace-events b/qapi/trace-events index 9e9008a1dc..70e049ea80 100644 --- a/qapi/trace-events +++ b/qapi/trace-events @@ -29,6 +29,6 @@ visit_type_int64(void *v, const char *name, int64_t *obj) "v=%p name=%s obj=%p" visit_type_size(void *v, const char *name, uint64_t *obj) "v=%p name=%s obj=%p" visit_type_bool(void *v, const char *name, bool *obj) "v=%p name=%s obj=%p" visit_type_str(void *v, const char *name, char **obj) "v=%p name=%s obj=%p" -visit_type_number(void *v, const char *name, double *obj) "v=%p name=%s obj=%p" +visit_type_number(void *v, const char *name, void *obj) "v=%p name=%s obj=%p" visit_type_any(void *v, const char *name, void *obj) "v=%p name=%s obj=%p" visit_type_null(void *v, const char *name, void *obj) "v=%p name=%s obj=%p" diff --git a/scripts/tracetool/__init__.py b/scripts/tracetool/__init__.py index b20fac34a3..0e3c9e146c 100644 --- a/scripts/tracetool/__init__.py +++ b/scripts/tracetool/__init__.py @@ -53,8 +53,6 @@ ALLOWED_TYPES = [ "bool", "unsigned", "signed", - "float", - "double", "int8_t", "uint8_t", "int16_t",