diff options
Diffstat (limited to 'gdb/NEWS')
| -rw-r--r-- | gdb/NEWS | 69 |
1 files changed, 58 insertions, 11 deletions
@@ -46,6 +46,27 @@ thread-specific pointer to the TIB. This feature is also supported when remote debugging using GDBserver. +* Static tracepoints + + Static tracepoints are calls in the user program into a tracing + library. One such library is a port of the LTTng kernel tracer to + userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust). + When debugging with GDBserver, GDB now supports combining the GDB + tracepoint machinery with such libraries. For example: the user can + use GDB to probe a static tracepoint marker (a call from the user + program into the tracing library) with the new "strace" command (see + "New commands" below). This creates a "static tracepoint" in the + breakpoint list, that can be manipulated with the same feature set + as fast and regular tracepoints. E.g., collect registers, local and + global variables, collect trace state variables, and define + tracepoint conditions. In addition, the user can collect extra + static tracepoint marker specific data, by collecting the new + $_sdata internal variable. When analyzing the trace buffer, you can + inspect $_sdata like any other variable available to GDB. For more + information, see the "Tracepoints" chapter in GDB user manual. New + remote packets have been defined to support static tracepoints, see + the "New remote packets" section below. + * New remote packets qGetTIBAddr @@ -61,23 +82,42 @@ qRelocInsn is particularly useful for stubs that support fast tracepoints. GDB reports support for this feature in the qSupported packet. +qTfSTM, qTsSTM + + List static tracepoint markers in the target program. + +qTSTMat + + List static tracepoint markers at a given address in the target + program. + +qXfer:statictrace:read + + Read the static trace data collected (by a `collect $_sdata' + tracepoint action). The remote stub reports support for this packet + to gdb's qSupported query. + * The source command now accepts a -s option to force searching for the script in the source search path even if the script name specifies a directory. * New features in the GDB remote stub, GDBserver - - GDBserver now support tracepoints (including fast tracepoints). - The feature is currently supported by the i386-linux and - amd64-linux builds. See the "Tracepoints support in gdbserver" - section in the manual for more information. GDBserver JIT - compiles the tracepoint's conditional agent expression bytecode - into native code whenever possible for low overhead dynamic - tracepoints conditionals. For such tracepoints, an expression - that examines program state is evaluated when the tracepoint is - reached, in order to determine whether to capture trace data. If - the condition is simple and false, processing the tracepoint - finishes very quickly and no data is gathered. + - GDBserver now support tracepoints (including fast tracepoints, and + static tracepoints). The feature is currently supported by the + i386-linux and amd64-linux builds. See the "Tracepoints support + in gdbserver" section in the manual for more information. + + GDBserver JIT compiles the tracepoint's conditional agent + expression bytecode into native code whenever possible for low + overhead dynamic tracepoints conditionals. For such tracepoints, + an expression that examines program state is evaluated when the + tracepoint is reached, in order to determine whether to capture + trace data. If the condition is simple and false, processing the + tracepoint finishes very quickly and no data is gathered. + + GDBserver interfaces with the UST (LTTng Userspace Tracer) library + for static tracepoints support. - GDBserver now supports x86_64 Windows 64-bit debugging. @@ -135,6 +175,13 @@ save breakpoints <filename> `save tracepoints' is a new alias for `save-tracepoints'. The latter is now deprecated. +info static-tracepoint-markers + Display information about static tracepoint markers in the target. + +strace FN | FILE:LINE | *ADDR | -m MARKER_ID + Define a static tracepoint by probing a marker at the given + function, line, address, or marker ID. + * Python scripting ** GDB now provides a new directory location, called the python directory, |