Re: [PATCH v7 3/6] Uprobes: Support SDT markers having reference count (semaphore)

2018-08-07 Thread Ravi Bangoria
Hi Oleg, >> I'm sorry. I didn't get this. How can uprobe go away without calling >> uprobe_unregister() >> -> rergister_for_each_vma() >>-> remove_breakpoint() >> And remove_breakpoint() will get called > > assuming that _unregister() will find the same vma with the probed insn. B

Re: [PATCH v7 3/6] Uprobes: Support SDT markers having reference count (semaphore)

2018-08-07 Thread Oleg Nesterov
Hi Ravi, On 08/06, Ravi Bangoria wrote: > > >> +static int delayed_uprobe_add(struct uprobe *uprobe, struct mm_struct *mm) > >> +{ > >> + struct delayed_uprobe *du; > >> + > >> + if (delayed_uprobe_check(uprobe, mm)) > >> + return 0; > >> + > >> + du = kzalloc(sizeof(*du), GFP_KERNEL)

Re: [PATCH v7 3/6] Uprobes: Support SDT markers having reference count (semaphore)

2018-08-06 Thread Ravi Bangoria
Hi Oleg, Sorry for bit late reply. On 08/03/2018 04:54 PM, Oleg Nesterov wrote: > Hi Ravi, > > I was going to give up and ack this series, but it seems I noticed > a bug... > > On 07/31, Ravi Bangoria wrote: >> >> +static int delayed_uprobe_add(struct uprobe *uprobe, struct mm_struct *mm) >> +

Re: [PATCH v7 3/6] Uprobes: Support SDT markers having reference count (semaphore)

2018-08-03 Thread Oleg Nesterov
Hi Ravi, I was going to give up and ack this series, but it seems I noticed a bug... On 07/31, Ravi Bangoria wrote: > > +static int delayed_uprobe_add(struct uprobe *uprobe, struct mm_struct *mm) > +{ > + struct delayed_uprobe *du; > + > + if (delayed_uprobe_check(uprobe, mm)) > +

[PATCH v7 3/6] Uprobes: Support SDT markers having reference count (semaphore)

2018-07-30 Thread Ravi Bangoria
Userspace Statically Defined Tracepoints[1] are dtrace style markers inside userspace applications. Applications like PostgreSQL, MySQL, Pthread, Perl, Python, Java, Ruby, Node.js, libvirt, QEMU, glib etc have these markers embedded in them. These markers are added by developer at important places