diff options
| author | Eric van Gyzen <vangyzen@FreeBSD.org> | 2023-07-27 22:06:33 +0000 |
|---|---|---|
| committer | Eric van Gyzen <vangyzen@FreeBSD.org> | 2023-08-01 17:28:50 +0000 |
| commit | 1112883e19aaef24082f8d24f9b3bc214046caad (patch) | |
| tree | 0ecdf69807c000efa5081790a36ed57d85fe6617 /cddl/contrib/opensolaris/lib/libdtrace/common | |
| parent | be1dd8e65bc607aae2e873ad80076a87869f6755 (diff) | |
dtrace: remove dead code for PR_REQUESTED
libproc's PR_REQUESTED is not implemented on FreeBSD. Remove dead code
in dtrace that would handle it.
Reviewed by: markj
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D41225
Diffstat (limited to 'cddl/contrib/opensolaris/lib/libdtrace/common')
| -rw-r--r-- | cddl/contrib/opensolaris/lib/libdtrace/common/dt_proc.c | 95 |
1 files changed, 0 insertions, 95 deletions
diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_proc.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_proc.c index 958d6ca34e85..b32dcea1f8ba 100644 --- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_proc.c +++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_proc.c @@ -366,84 +366,6 @@ dt_proc_attach(dt_proc_t *dpr, int exec) } } -/* - * Wait for a stopped process to be set running again by some other debugger. - * This is typically not required by /proc-based debuggers, since the usual - * model is that one debugger controls one victim. But DTrace, as usual, has - * its own needs: the stop() action assumes that prun(1) or some other tool - * will be applied to resume the victim process. This could be solved by - * adding a PCWRUN directive to /proc, but that seems like overkill unless - * other debuggers end up needing this functionality, so we implement a cheap - * equivalent to PCWRUN using the set of existing kernel mechanisms. - * - * Our intent is really not just to wait for the victim to run, but rather to - * wait for it to run and then stop again for a reason other than the current - * PR_REQUESTED stop. Since PCWSTOP/Pstopstatus() can be applied repeatedly - * to a stopped process and will return the same result without affecting the - * victim, we can just perform these operations repeatedly until Pstate() - * changes, the representative LWP ID changes, or the stop timestamp advances. - * dt_proc_control() will then rediscover the new state and continue as usual. - * When the process is still stopped in the same exact state, we sleep for a - * brief interval before waiting again so as not to spin consuming CPU cycles. - */ -static void -dt_proc_waitrun(dt_proc_t *dpr) -{ - printf("%s:%s(%d): not implemented\n", __FUNCTION__, __FILE__, - __LINE__); -#ifdef DOODAD - struct ps_prochandle *P = dpr->dpr_proc; - const lwpstatus_t *psp = &Pstatus(P)->pr_lwp; - - int krflag = psp->pr_flags & (PR_KLC | PR_RLC); - timestruc_t tstamp = psp->pr_tstamp; - lwpid_t lwpid = psp->pr_lwpid; - - const long wstop = PCWSTOP; - int pfd = Pctlfd(P); - - assert(DT_MUTEX_HELD(&dpr->dpr_lock)); - assert(psp->pr_flags & PR_STOPPED); - assert(Pstate(P) == PS_STOP); - - /* - * While we are waiting for the victim to run, clear PR_KLC and PR_RLC - * so that if the libdtrace client is killed, the victim stays stopped. - * dt_proc_destroy() will also observe this and perform PRELEASE_HANG. - */ - (void) Punsetflags(P, krflag); - Psync(P); - - (void) pthread_mutex_unlock(&dpr->dpr_lock); - - while (!dpr->dpr_quit) { - if (write(pfd, &wstop, sizeof (wstop)) == -1 && errno == EINTR) - continue; /* check dpr_quit and continue waiting */ - - (void) pthread_mutex_lock(&dpr->dpr_lock); - (void) Pstopstatus(P, PCNULL, 0); - psp = &Pstatus(P)->pr_lwp; - - /* - * If we've reached a new state, found a new representative, or - * the stop timestamp has changed, restore PR_KLC/PR_RLC to its - * original setting and then return with dpr_lock held. - */ - if (Pstate(P) != PS_STOP || psp->pr_lwpid != lwpid || - bcmp(&psp->pr_tstamp, &tstamp, sizeof (tstamp)) != 0) { - (void) Psetflags(P, krflag); - Psync(P); - return; - } - - (void) pthread_mutex_unlock(&dpr->dpr_lock); - (void) poll(NULL, 0, MILLISEC / 2); - } - - (void) pthread_mutex_lock(&dpr->dpr_lock); -#endif -} - typedef struct dt_proc_control_data { dtrace_hdl_t *dpcd_hdl; /* DTrace handle */ dt_proc_t *dpcd_proc; /* proccess to control */ @@ -533,23 +455,6 @@ dt_proc_control(void *arg) pid, psp->pr_why, psp->pr_what); /* - * If the process stops showing PR_REQUESTED, then the - * DTrace stop() action was applied to it or another - * debugging utility (e.g. pstop(1)) asked it to stop. - * In either case, the user's intention is for the - * process to remain stopped until another external - * mechanism (e.g. prun(1)) is applied. So instead of - * setting the process running ourself, we wait for - * someone else to do so. Once that happens, we return - * to our normal loop waiting for an event of interest. - */ - if (psp->pr_why == PR_REQUESTED) { - dt_proc_waitrun(dpr); - (void) pthread_mutex_unlock(&dpr->dpr_lock); - continue; - } - - /* * If the process stops showing one of the events that * we are tracing, perform the appropriate response. * Note that we ignore PR_SUSPENDED, PR_CHECKPOINT, and |