Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/19, Ravi Bangoria wrote: > > Hi Oleg, > > On 03/14/2018 10:29 PM, Oleg Nesterov wrote: > > On 03/13, Ravi Bangoria wrote: > >> +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct > >> *vma) > >> +{ > >> + unsigned long vaddr = vma_offset_to_vaddr(vma,

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/19, Ravi Bangoria wrote: > > Hi Oleg, > > On 03/14/2018 10:29 PM, Oleg Nesterov wrote: > > On 03/13, Ravi Bangoria wrote: > >> +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct > >> *vma) > >> +{ > >> + unsigned long vaddr = vma_offset_to_vaddr(vma,

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Hi Oleg, On 03/14/2018 10:29 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct >> *vma) >> +{ >> +unsigned long vaddr = vma_offset_to_vaddr(vma, tu->ref_ctr_offset); >> + >> +return tu->ref_ctr_offset &&

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Hi Oleg, On 03/14/2018 10:29 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct >> *vma) >> +{ >> +unsigned long vaddr = vma_offset_to_vaddr(vma, tu->ref_ctr_offset); >> + >> +return tu->ref_ctr_offset &&

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15, Steven Rostedt wrote: > > On Tue, 13 Mar 2018 18:26:00 +0530 > Ravi Bangoria wrote: > > > +static void sdt_increment_ref_ctr(struct trace_uprobe *tu) > > +{ > > + struct uprobe_map_info *info; > > + struct vm_area_struct *vma; > > + unsigned long

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15, Steven Rostedt wrote: > > On Tue, 13 Mar 2018 18:26:00 +0530 > Ravi Bangoria wrote: > > > +static void sdt_increment_ref_ctr(struct trace_uprobe *tu) > > +{ > > + struct uprobe_map_info *info; > > + struct vm_area_struct *vma; > > + unsigned long vaddr; > > + > > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/16/2018 05:09 PM, Oleg Nesterov wrote: > On 03/16, Ravi Bangoria wrote: >> On 03/15/2018 08:00 PM, Oleg Nesterov wrote: >>> Note to mention that sdt_find_vma() can return NULL but the callers do >>> vma_offset_to_vaddr(vma) without any check. >> If the "mm" we are passing to sdt_find_vma()

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/16/2018 05:09 PM, Oleg Nesterov wrote: > On 03/16, Ravi Bangoria wrote: >> On 03/15/2018 08:00 PM, Oleg Nesterov wrote: >>> Note to mention that sdt_find_vma() can return NULL but the callers do >>> vma_offset_to_vaddr(vma) without any check. >> If the "mm" we are passing to sdt_find_vma()

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/16, Ravi Bangoria wrote: > > On 03/15/2018 08:00 PM, Oleg Nesterov wrote: > > Note to mention that sdt_find_vma() can return NULL but the callers do > > vma_offset_to_vaddr(vma) without any check. > > If the "mm" we are passing to sdt_find_vma() is returned by >

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/16, Ravi Bangoria wrote: > > On 03/15/2018 08:00 PM, Oleg Nesterov wrote: > > Note to mention that sdt_find_vma() can return NULL but the callers do > > vma_offset_to_vaddr(vma) without any check. > > If the "mm" we are passing to sdt_find_vma() is returned by >

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 08:31 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> +sdt_update_ref_ctr(struct mm_struct *mm, unsigned long vaddr, short d) >> +{ >> +void *kaddr; >> +struct page *page; >> +struct vm_area_struct *vma; >> +int ret = 0; >> +unsigned short orig = 0;

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 08:31 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> +sdt_update_ref_ctr(struct mm_struct *mm, unsigned long vaddr, short d) >> +{ >> +void *kaddr; >> +struct page *page; >> +struct vm_area_struct *vma; >> +int ret = 0; >> +unsigned short orig = 0;

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 08:00 PM, Oleg Nesterov wrote: > On 03/15, Oleg Nesterov wrote: >>> +static struct vm_area_struct * >>> +sdt_find_vma(struct mm_struct *mm, struct trace_uprobe *tu) >>> +{ >>> + struct vm_area_struct *tmp; >>> + >>> + for (tmp = mm->mmap; tmp != NULL; tmp = tmp->vm_next) >>> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 08:00 PM, Oleg Nesterov wrote: > On 03/15, Oleg Nesterov wrote: >>> +static struct vm_area_struct * >>> +sdt_find_vma(struct mm_struct *mm, struct trace_uprobe *tu) >>> +{ >>> + struct vm_area_struct *tmp; >>> + >>> + for (tmp = mm->mmap; tmp != NULL; tmp = tmp->vm_next) >>> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 07:51 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> @@ -1053,6 +1056,9 @@ int uprobe_mmap(struct vm_area_struct *vma) >> struct uprobe *uprobe, *u; >> struct inode *inode; >> >> +if (uprobe_mmap_callback) >> +uprobe_mmap_callback(vma); >> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 07:51 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> @@ -1053,6 +1056,9 @@ int uprobe_mmap(struct vm_area_struct *vma) >> struct uprobe *uprobe, *u; >> struct inode *inode; >> >> +if (uprobe_mmap_callback) >> +uprobe_mmap_callback(vma); >> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 10:18 PM, Steven Rostedt wrote: > On Tue, 13 Mar 2018 18:26:00 +0530 > Ravi Bangoria wrote: > >> +static void sdt_increment_ref_ctr(struct trace_uprobe *tu) >> +{ >> +struct uprobe_map_info *info; >> +struct vm_area_struct *vma; >> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15/2018 10:18 PM, Steven Rostedt wrote: > On Tue, 13 Mar 2018 18:26:00 +0530 > Ravi Bangoria wrote: > >> +static void sdt_increment_ref_ctr(struct trace_uprobe *tu) >> +{ >> +struct uprobe_map_info *info; >> +struct vm_area_struct *vma; >> +unsigned long vaddr; >> + >> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On Tue, 13 Mar 2018 18:26:00 +0530 Ravi Bangoria wrote: > +static void sdt_increment_ref_ctr(struct trace_uprobe *tu) > +{ > + struct uprobe_map_info *info; > + struct vm_area_struct *vma; > + unsigned long vaddr; > + > + uprobe_start_dup_mmap();

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On Tue, 13 Mar 2018 18:26:00 +0530 Ravi Bangoria wrote: > +static void sdt_increment_ref_ctr(struct trace_uprobe *tu) > +{ > + struct uprobe_map_info *info; > + struct vm_area_struct *vma; > + unsigned long vaddr; > + > + uprobe_start_dup_mmap(); Please add a comment here that

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/13, Ravi Bangoria wrote: > > +sdt_update_ref_ctr(struct mm_struct *mm, unsigned long vaddr, short d) > +{ > + void *kaddr; > + struct page *page; > + struct vm_area_struct *vma; > + int ret = 0; > + unsigned short orig = 0; > + > + if (vaddr == 0) > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/13, Ravi Bangoria wrote: > > +sdt_update_ref_ctr(struct mm_struct *mm, unsigned long vaddr, short d) > +{ > + void *kaddr; > + struct page *page; > + struct vm_area_struct *vma; > + int ret = 0; > + unsigned short orig = 0; > + > + if (vaddr == 0) > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15, Oleg Nesterov wrote: > > > +static struct vm_area_struct * > > +sdt_find_vma(struct mm_struct *mm, struct trace_uprobe *tu) > > +{ > > + struct vm_area_struct *tmp; > > + > > + for (tmp = mm->mmap; tmp != NULL; tmp = tmp->vm_next) > > + if (sdt_valid_vma(tu, tmp)) > > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/15, Oleg Nesterov wrote: > > > +static struct vm_area_struct * > > +sdt_find_vma(struct mm_struct *mm, struct trace_uprobe *tu) > > +{ > > + struct vm_area_struct *tmp; > > + > > + for (tmp = mm->mmap; tmp != NULL; tmp = tmp->vm_next) > > + if (sdt_valid_vma(tu, tmp)) > > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/13, Ravi Bangoria wrote: > > @@ -1053,6 +1056,9 @@ int uprobe_mmap(struct vm_area_struct *vma) > struct uprobe *uprobe, *u; > struct inode *inode; > > + if (uprobe_mmap_callback) > + uprobe_mmap_callback(vma); > + > if (no_uprobe_events() || !valid_vma(vma,

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/13, Ravi Bangoria wrote: > > @@ -1053,6 +1056,9 @@ int uprobe_mmap(struct vm_area_struct *vma) > struct uprobe *uprobe, *u; > struct inode *inode; > > + if (uprobe_mmap_callback) > + uprobe_mmap_callback(vma); > + > if (no_uprobe_events() || !valid_vma(vma,

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/14/2018 10:29 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct >> *vma) >> +{ >> +unsigned long vaddr = vma_offset_to_vaddr(vma, tu->ref_ctr_offset); >> + >> +return tu->ref_ctr_offset && >> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/14/2018 10:29 PM, Oleg Nesterov wrote: > On 03/13, Ravi Bangoria wrote: >> +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct >> *vma) >> +{ >> +unsigned long vaddr = vma_offset_to_vaddr(vma, tu->ref_ctr_offset); >> + >> +return tu->ref_ctr_offset && >> +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On Tue, 13 Mar 2018 18:26:00 +0530 Ravi Bangoria wrote: > include/linux/uprobes.h | 2 + > kernel/events/uprobes.c | 6 ++ > kernel/trace/trace_uprobe.c | 172 > +++- I'm currently traveling, but I'll try to

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On Tue, 13 Mar 2018 18:26:00 +0530 Ravi Bangoria wrote: > include/linux/uprobes.h | 2 + > kernel/events/uprobes.c | 6 ++ > kernel/trace/trace_uprobe.c | 172 > +++- I'm currently traveling, but I'll try to look at it in a week or two. --

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/13, Ravi Bangoria wrote: > > +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct > *vma) > +{ > + unsigned long vaddr = vma_offset_to_vaddr(vma, tu->ref_ctr_offset); > + > + return tu->ref_ctr_offset && > + vma->vm_file && > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

On 03/13, Ravi Bangoria wrote: > > +static bool sdt_valid_vma(struct trace_uprobe *tu, struct vm_area_struct > *vma) > +{ > + unsigned long vaddr = vma_offset_to_vaddr(vma, tu->ref_ctr_offset); > + > + return tu->ref_ctr_offset && > + vma->vm_file && > +

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Hi Masami, On 03/14/2018 07:18 PM, Masami Hiramatsu wrote: > Hi Ravi, > > On Tue, 13 Mar 2018 18:26:00 +0530 > Ravi Bangoria wrote: > >> Userspace Statically Defined Tracepoints[1] are dtrace style markers >> inside userspace applications. These markers are

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Hi Masami, On 03/14/2018 07:18 PM, Masami Hiramatsu wrote: > Hi Ravi, > > On Tue, 13 Mar 2018 18:26:00 +0530 > Ravi Bangoria wrote: > >> Userspace Statically Defined Tracepoints[1] are dtrace style markers >> inside userspace applications. These markers are added by developer at >> important

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Hi Ravi, On Tue, 13 Mar 2018 18:26:00 +0530 Ravi Bangoria wrote: > Userspace Statically Defined Tracepoints[1] are dtrace style markers > inside userspace applications. These markers are added by developer at > important places in the code. Each marker source

Re: [PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Hi Ravi, On Tue, 13 Mar 2018 18:26:00 +0530 Ravi Bangoria wrote: > Userspace Statically Defined Tracepoints[1] are dtrace style markers > inside userspace applications. These markers are added by developer at > important places in the code. Each marker source expands to a single > nop

[PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Userspace Statically Defined Tracepoints[1] are dtrace style markers inside userspace applications. These markers are added by developer at important places in the code. Each marker source expands to a single nop instruction in the compiled code but there may be additional overhead for computing

[PATCH 5/8] trace_uprobe: Support SDT markers having reference count (semaphore)

Userspace Statically Defined Tracepoints[1] are dtrace style markers inside userspace applications. These markers are added by developer at important places in the code. Each marker source expands to a single nop instruction in the compiled code but there may be additional overhead for computing