From 186f7872ea8e857a3f8f6d3b72643e2d5a515bea Mon Sep 17 00:00:00 2001 From: Kris Van Hees Date: Sun, 9 Sep 2012 16:56:15 -0400 Subject: [PATCH] Cleanup (and adding) of SDT probe points. Changed io SDT probe points to be located at the buffer_head level rather than the bio level. This may need to be revisted depending on further analysis, but doing it this way provides consistent semantics that were not guaranteed by the previous bio-based placement. Changed the sched STD probes to not pass irrelevant arguments, and to pass specific runqueue CPU information. The CPU information is not available from the task structure, so it needs to be passed explicily. Added proc SDT probes start and lwp-start. Added proc SDT probes for signal-discard and signal-clear. Corrected the argument to the exit proc SDT probe, which should indicate the reason for the process termination (exit, killed, core dumped) rather than the return code of the process. Provided argument information for all the new (and changed) SDT probe points. This depends on working xlator support in userspace. Enabling of SDT probes now uses a generic dtrace_invop_(enable|disable) rather than SDT-specific functions. SDT probes are not destroyed correctly, to ensure that subsequent uses will not result in unpleasant events. Signed-off-by: Kris Van Hees --- dtrace/sdt_dev.c | 94 +++++++++++++++++++++++++++++++++++++++++------- dtrace/sdt_mod.c | 2 +- 2 files changed, 82 insertions(+), 14 deletions(-) diff --git a/dtrace/sdt_dev.c b/dtrace/sdt_dev.c index 847a4dc60e13..a876626ceb45 100644 --- a/dtrace/sdt_dev.c +++ b/dtrace/sdt_dev.c @@ -43,24 +43,67 @@ static int sdt_probetab_size; static int sdt_probetab_mask; static sdt_argdesc_t sdt_args[] = { - { "proc", "create", 0, 0, "struct task_struct *", }, + /* + * { name, provider, ndx, mapping, native, xlate } + */ + { "io", "done", 0, 0, "struct buffer_head *", "bufinfo_t *" }, + { "io", "done", 1, 0, "struct buffer_head *", "devinfo_t *" }, + { "io", "done", 2, 0, "struct buffer_head *", "fileinfo_t *" }, + { "io", "start", 0, 0, "struct buffer_head *", "bufinfo_t *" }, + { "io", "start", 1, 0, "struct buffer_head *", "devinfo_t *" }, + { "io", "start", 2, 0, "struct buffer_head *", "fileinfo_t *" }, + { "io", "wait-done", 0, 0, "struct buffer_head *", "bufinfo_t *" }, + { "io", "wait-done", 1, 0, "struct buffer_head *", "devinfo_t *" }, + { "io", "wait-done", 2, 0, "struct buffer_head *", "fileinfo_t *" }, + { "io", "wait-start", 0, 0, "struct buffer_head *", "bufinfo_t *" }, + { "io", "wait-start", 1, 0, "struct buffer_head *", "devinfo_t *" }, + { "io", "wait-start", 2, 0, "struct buffer_head *", "fileinfo_t *" }, + + { "proc", "create", 0, 0, "struct task_struct *", "psinfo_t *" }, { "proc", "exec", 0, 0, "char *", }, { "proc", "exec-failure", 0, 0, "int", }, { "proc", "exit", 0, 0, "int", }, - { "proc", "lwp_create", 0, 0, "struct task_struct *", }, +#if 0 + { "proc", "fault", 0, 0, "int", }, + { "proc", "fault", 1, 1, "siginfo_t", }, +#endif + { "proc", "lwp_create", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "proc", "lwp_create", 1, 0, "struct task_struct *", "psinfo_t *" }, { "proc", "lwp_exit", 0, 0, "int", }, + { "proc", "signal-clear", 0, 0, "int", }, + { "proc", "signal-discard", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "proc", "signal-discard", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "proc", "signal-discard", 2, 1, "int", }, { "proc", "signal-handle", 0, 0, "int" }, - { "proc", "signal-handle", 1, 0 /* 1 */, "siginfo_t *" }, - { "proc", "signal-handle", 2, 0 /* 2 */, "void (*)(void)" }, - { "proc", "signal-send", 0, 0, "struct task_struct *", }, - { "proc", "signal-send", 1, 0, "int", }, - - { "sched", "tick", 0, 0, "struct task_struct *", }, + { "proc", "signal-handle", 1, 1, "siginfo_t *" }, + { "proc", "signal-handle", 2, 2, "void (*)(void)" }, + { "proc", "signal-send", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "proc", "signal-send", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "proc", "signal-send", 2, 1, "int", }, + + { "sched", "change-pri", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "change-pri", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "sched", "change-pri", 2, 1, "int", }, + { "sched", "dequeue", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "dequeue", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "sched", "dequeue", 2, 1, "cpuinfo_t *", }, + { "sched", "dequeue", 3, 2, "int", }, + { "sched", "enqueue", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "enqueue", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "sched", "enqueue", 2, 1, "cpuinfo_t *", }, + { "sched", "off-cpu", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "off-cpu", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "sched", "surrender", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "surrender", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "sched", "tick", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "tick", 1, 0, "struct task_struct *", "psinfo_t *" }, + { "sched", "wakeup", 0, 0, "struct task_struct *", "lwpsinfo_t *" }, + { "sched", "wakeup", 1, 0, "struct task_struct *", "psinfo_t *" }, { NULL, } }; -static int sdt_invop(struct pt_regs *regs) +static uint8_t sdt_invop(struct pt_regs *regs) { sdt_probe_t *sdt = sdt_probetab[SDT_ADDR2NDX(regs->ip)]; @@ -164,7 +207,7 @@ int _sdt_enable(void *arg, dtrace_id_t id, void *parg) { sdt_probe_t *sdp = parg; - sdt_probe_enable(sdp->sdp_patchpoint); + dtrace_invop_enable(sdp->sdp_patchpoint); return 0; } @@ -172,7 +215,7 @@ void _sdt_disable(void *arg, dtrace_id_t id, void *parg) { sdt_probe_t *sdp = parg; - sdt_probe_disable(sdp->sdp_patchpoint); + dtrace_invop_disable(sdp->sdp_patchpoint, sdp->sdp_savedval); } void sdt_getargdesc(void *arg, dtrace_id_t id, void *parg, @@ -219,6 +262,33 @@ uint64_t sdt_getarg(void *arg, dtrace_id_t id, void *parg, int argno, void sdt_destroy(void *arg, dtrace_id_t id, void *parg) { + sdt_probe_t *sdp = parg; + + sdp->sdp_module->sdt_nprobes--; + + while (sdp != NULL) { + sdt_probe_t *old = sdp, *last, *hash; + int ndx; + + ndx = SDT_ADDR2NDX(sdp->sdp_patchpoint); + last = NULL; + hash = sdt_probetab[ndx]; + + while (hash != sdp) { + ASSERT(hash != NULL); + last = hash; + hash = hash->sdp_hashnext; + } + + if (last != NULL) + last->sdp_hashnext = sdp->sdp_hashnext; + else + sdt_probetab[ndx] = sdp->sdp_hashnext; + + kfree(sdp->sdp_name); + sdp = sdp->sdp_next; + kfree(old); + } } static long sdt_ioctl(struct file *file, @@ -260,8 +330,6 @@ int sdt_dev_init(void) pr_err("%s: Can't register misc device %d\n", sdt_dev.name, sdt_dev.minor); - dtrace_register_builtins(); /* FIXME */ - if (sdt_probetab_size == 0) sdt_probetab_size = SDT_PROBETAB_SIZE; diff --git a/dtrace/sdt_mod.c b/dtrace/sdt_mod.c index 55f7c862097e..d9b93f539d08 100644 --- a/dtrace/sdt_mod.c +++ b/dtrace/sdt_mod.c @@ -119,7 +119,7 @@ static dtrace_pops_t sdt_pops = { NULL, NULL, sdt_getargdesc, - sdt_getarg, + NULL /* sdt_getarg */, NULL, sdt_destroy, }; -- 2.50.1