linux/kernel/trace/trace_uprobe.c, branch v4.20

tracing/uprobes: Fix to return -EFAULT if copy_from_user failed

2018-10-11T02:19:11Z

Fix probe_mem_read() to return -EFAULT if copy_from_user() failed. The copy_from_user() returns remaining bytes when it failed, but probe_mem_read() caller expects it returns error code like as probe_kernel_read(). Link: http://lkml.kernel.org/r/153547306719.26502.8353484532699160223.stgit@devbox Reported-by: Dan Carpenter Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Add $argN for accessing function args

2018-10-11T02:19:11Z

Add $argN special fetch variable for accessing function arguments. This allows user to trace the Nth argument easily at the function entry. Note that this returns most probably assignment of registers and stacks. In some case, it may not work well. If you need to access correct registers or stacks you should use perf-probe. Link: http://lkml.kernel.org/r/152465888632.26224.3412465701570253696.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Unify fetch_insn processing common part

2018-10-11T02:19:09Z

Unify the fetch_insn bottom process (from stage 2: dereference indirect data) from kprobe and uprobe events, since those are mostly same. Link: http://lkml.kernel.org/r/152465879965.26224.8547240824606804815.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Append traceprobe_ for exported function

2018-10-11T02:19:09Z

Append traceprobe_ for exported function set_print_fmt() as same as other functions. Link: http://lkml.kernel.org/r/152465877071.26224.11143125027282999726.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Return consumed bytes of dynamic area

2018-10-11T02:19:08Z

Cleanup string fetching routine so that returns the consumed bytes of dynamic area and store the string information as data_loc format instead of data_rloc. This simplifies the fetcharg loop. Link: http://lkml.kernel.org/r/152465874163.26224.12125143907501289031.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Unify fetch type tables

2018-10-11T02:19:08Z

Unify {k,u}probe_fetch_type_table to probe_fetch_type_table because the main difference of those type tables (fetcharg methods) are gone. Now we can consolidate it. Link: http://lkml.kernel.org/r/152465871274.26224.13999436317830479698.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Introduce new argument fetching code

2018-10-11T02:19:07Z

Replace {k,u}probe event argument fetching framework with switch-case based. Currently that is implemented with structures, macros and chain of function-pointers, which is more complicated than necessary and may get a performance penalty by retpoline. This simplify that with an array of "fetch_insn" (opcode and oprands), and make process_fetch_insn() just interprets it. No function pointers are used. Link: http://lkml.kernel.org/r/152465868340.26224.2551120475197839464.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Cleanup argument field definition

2018-10-11T02:19:06Z

Cleanup event argument definition code in one place for maintenancability. Link: http://lkml.kernel.org/r/152465862529.26224.9068605421476018902.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: probeevent: Cleanup print argument functions

2018-10-11T02:19:06Z

Cleanup the print-argument function to decouple it into print-name and print-value, so that it can support more flexible expression, like array type. Link: http://lkml.kernel.org/r/152465859635.26224.13452846788717102315.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

trace_uprobe: support reference counter in fd-based uprobe

2018-10-11T02:14:17Z

This patch enables uprobes with reference counter in fd-based uprobe. Highest 32 bits of perf_event_attr.config is used to stored offset of the reference count (semaphore). Format information in /sys/bus/event_source/devices/uprobe/format/ is updated to reflect this new feature. Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com Cc: Oleg Nesterov Acked-by: Peter Zijlstra (Intel) Reviewed-and-tested-by: Ravi Bangoria Signed-off-by: Song Liu Signed-off-by: Steven Rostedt (VMware)