CVS commit: src

["Kamil Rytarowski" <kamil%netbsd.org@localhost>]

Module Name:    src
Committed By:   kamil
Date:           Sat Jan 14 06:36:52 UTC 2017

Modified Files:
        src/sys/kern: kern_lwp.c sys_ptrace_common.c
        src/sys/sys: proc.h ptrace.h siginfo.h
        src/tests/kernel: t_ptrace_wait.c

Log Message:
Introduce PTRACE_LWP_{CREATE,EXIT} in ptrace(2) and TRAP_LWP in siginfo(5)

Add interface in ptrace(2) to track thread (LWP) events:
 - birth,
 - termination.

The purpose of this thread is to keep track of the current thread state in
a tracee and apply e.g. per-thread designed hardware assisted watchpoints.

This interface reuses the EVENT_MASK and PROCESS_STATE interface, and
shares it with PTRACE_FORK, PTRACE_VFORK and PTRACE_VFORK_DONE.

Change the following structure:

typedef struct ptrace_state {
        int     pe_report_event;
        pid_t   pe_other_pid;
} ptrace_state_t;

to

typedef struct ptrace_state {
        int     pe_report_event;
        union {
                pid_t   _pe_other_pid;
                lwpid_t _pe_lwp;
        } _option;
} ptrace_state_t;

#define pe_other_pid    _option._pe_other_pid
#define pe_lwp          _option._pe_lwp

This keeps size of ptrace_state_t unchanged as both pid_t and lwpid_t are
defined as int32_t-like integer. This change does not break existing
prebuilt software and has minimal effect on necessity for source-code
changes. In summary, this change should be binary compatible and shouldn't
break build of existing software.

Introduce new siginfo(5) type for LWP events under the SIGTRAP signal:
TRAP_LWP. This change will help debuggers to distinguish exact source of
SIGTRAP.

Add two basic t_ptrace_wait* tests:
lwp_create1:
    Verify that 1 LWP creation is intercepted by ptrace(2) with
    EVENT_MASK set to PTRACE_LWP_CREATE

lwp_exit1:
    Verify that 1 LWP creation is intercepted by ptrace(2) with
    EVENT_MASK set to PTRACE_LWP_EXIT

All tests are passing.

Surfing the previous kernel ABI bump to 7.99.59 for PTRACE_VFORK{,_DONE}.

Sponsored by <The NetBSD Foundation>


To generate a diff of this commit:
cvs rdiff -u -r1.185 -r1.186 src/sys/kern/kern_lwp.c
cvs rdiff -u -r1.9 -r1.10 src/sys/kern/sys_ptrace_common.c
cvs rdiff -u -r1.336 -r1.337 src/sys/sys/proc.h
cvs rdiff -u -r1.53 -r1.54 src/sys/sys/ptrace.h
cvs rdiff -u -r1.28 -r1.29 src/sys/sys/siginfo.h
cvs rdiff -u -r1.58 -r1.59 src/tests/kernel/t_ptrace_wait.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.