similar to: [libvirt] [RFC] Implementing ftrace support for libvirt

Hi, I am wondering what tools are available to troubleshoot KVM I/O problems on CentOS 5, given that the kernel is 2.6.18 with some backports to support virtualisation? kvm_stat / kvmtrace - These seem to be available in the kvm-tools package. ftrace related things seem not to be available. OProfile is available, can it be used? Also, SystemTap is available, can it be used? Anything

When using -fPIE/PIC with function tracing, the compiler generates a call through the GOT (call *__fentry__ at GOTPCREL). This instruction takes 6 bytes instead of 5 on the usual relative call. If PIE is enabled, replace the 6th byte of the GOT call by a 1-byte nop so ftrace can handle the previous 5-bytes as before. Position Independent Executable (PIE) support will allow to extended the KASLR

When using -fPIE/PIC with function tracing, the compiler generates a call through the GOT (call *__fentry__ at GOTPCREL). This instruction takes 6 bytes instead of 5 on the usual relative call. If PIE is enabled, replace the 6th byte of the GOT call by a 1-byte nop so ftrace can handle the previous 5-bytes as before. Position Independent Executable (PIE) support will allow to extended the KASLR

On Thu, 24 May 2018 13:40:24 +0200 Petr Mladek <pmladek at suse.com> wrote: > On Wed 2018-05-23 12:54:15, Thomas Garnier wrote: > > When using -fPIE/PIC with function tracing, the compiler generates a > > call through the GOT (call *__fentry__ at GOTPCREL). This instruction > > takes 6 bytes instead of 5 on the usual relative call. > > > > If PIE is

On Wed, Feb 15, 2023 at 03:33:44PM -0700, Ross Zwisler wrote: > Changes in v2: > * Dropped patches which were pulled into maintainer trees. > * Split BPF patches out into another series targeting bpf-next. > * trace-agent now falls back to debugfs if tracefs isn't present. > * Added Acked-by from mst at redhat.com to series. > * Added a typo fixup for the virtio-trace

On Thu, May 24, 2018 at 1:16 PM Steven Rostedt <rostedt at goodmis.org> wrote: > On Thu, 24 May 2018 13:40:24 +0200 > Petr Mladek <pmladek at suse.com> wrote: > > On Wed 2018-05-23 12:54:15, Thomas Garnier wrote: > > > When using -fPIE/PIC with function tracing, the compiler generates a > > > call through the GOT (call *__fentry__ at GOTPCREL). This

On Wed 2018-05-23 12:54:15, Thomas Garnier wrote: > When using -fPIE/PIC with function tracing, the compiler generates a > call through the GOT (call *__fentry__ at GOTPCREL). This instruction > takes 6 bytes instead of 5 on the usual relative call. > > If PIE is enabled, replace the 6th byte of the GOT call by a 1-byte nop > so ftrace can handle the previous 5-bytes as before.

On Wed 2018-05-23 12:54:15, Thomas Garnier wrote: > When using -fPIE/PIC with function tracing, the compiler generates a > call through the GOT (call *__fentry__ at GOTPCREL). This instruction > takes 6 bytes instead of 5 on the usual relative call. > > If PIE is enabled, replace the 6th byte of the GOT call by a 1-byte nop > so ftrace can handle the previous 5-bytes as before.

Hi Here is System tap''s representives response to my comments and mine back to that list. Since it was on a public mailing list i''m reposting here, since there is obvious interest. James Dickens uadmin.blogspot.com ---------- Forwarded message ---------- From: James Dickens <jamesd.wi at gmail.com> Date: Sep 13, 2006 1:51 PM Subject: Re: Systemtap vs Dtrace web page

On Wed, 4 Oct 2017 14:19:56 -0700 Thomas Garnier <thgarnie at google.com> wrote: > When using -fPIE/PIC with function tracing, the compiler generates a > call through the GOT (call *__fentry__ at GOTPCREL). This instruction > takes 6 bytes instead of 5 on the usual relative call. > > With this change, function tracing supports 6 bytes on traceable > function and can

On Thu, 5 Oct 2017 09:01:14 -0700 Thomas Garnier <thgarnie at google.com> wrote: > On Thu, Oct 5, 2017 at 6:06 AM, Steven Rostedt <rostedt at goodmis.org> wrote: > > On Wed, 4 Oct 2017 14:19:56 -0700 > > Thomas Garnier <thgarnie at google.com> wrote: > > > >> When using -fPIE/PIC with function tracing, the compiler generates a > >> call

On Thu, Oct 5, 2017 at 6:06 AM, Steven Rostedt <rostedt at goodmis.org> wrote: > On Wed, 4 Oct 2017 14:19:56 -0700 > Thomas Garnier <thgarnie at google.com> wrote: > >> When using -fPIE/PIC with function tracing, the compiler generates a >> call through the GOT (call *__fentry__ at GOTPCREL). This instruction >> takes 6 bytes instead of 5 on the usual

On Thu, Oct 5, 2017 at 6:06 AM, Steven Rostedt <rostedt at goodmis.org> wrote: > On Wed, 4 Oct 2017 14:19:56 -0700 > Thomas Garnier <thgarnie at google.com> wrote: > >> When using -fPIE/PIC with function tracing, the compiler generates a >> call through the GOT (call *__fentry__ at GOTPCREL). This instruction >> takes 6 bytes instead of 5 on the usual

When using -fPIE/PIC with function tracing, the compiler generates a call through the GOT (call *__fentry__ at GOTPCREL). This instruction takes 6 bytes instead of 5 on the usual relative call. With this change, function tracing supports 6 bytes on traceable function and can still replace relative calls on the ftrace assembly functions. Position Independent Executable (PIE) support will allow to

Not sure if this document will be shown to any dtrace users but here is a link if you want to comment on it http://sources.redhat.com/systemtap/wiki/SystemtapDtraceComparison I have went line by line and commented on its content and in accuracies and posted it both to the systemtap email list and my blog, you can see the blogged version at

Send CentOS-announce mailing list submissions to centos-announce at centos.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.centos.org/mailman/listinfo/centos-announce or, via email, send a message with subject or body 'help' to centos-announce-request at centos.org You can reach the person managing the list at centos-announce-owner at centos.org When

CentOS Errata and Bugfix Advisory 2012:1337 Upstream details at : https://rhn.redhat.com/errata/RHBA-2012-1337.html The following updated files have been uploaded and are currently syncing to the mirrors: ( sha256sum Filename ) i386: 78e4e7183cabb6a0f708f24c57a8c4aaeed1d6e564aa49d4e4c85cce9fa1efa2 systemtap-1.7-5.el6_3.1.i686.rpm

CentOS Errata and Bugfix Advisory 2013:1858 Upstream details at : https://rhn.redhat.com/errata/RHBA-2013-1858.html The following updated files have been uploaded and are currently syncing to the mirrors: ( sha256sum Filename ) i386: 44c4a9c1d76fd1d64fb959a58507b15d3137d102848ee46929180dd618d2aebd systemtap-2.3-4.el6_5.i686.rpm

CentOS Errata and Security Advisory 2012:0376 Moderate Upstream details at : https://rhn.redhat.com/errata/RHSA-2012-0376.html The following updated files have been uploaded and are currently syncing to the mirrors: ( sha256sum Filename ) i386: be4161ae13dff00f28989c3d0611be9a2e2c1ba455bf2f97ef84b5187873231d systemtap-1.6-5.el6_2.i686.rpm

CentOS Errata and Security Advisory 2012:0376 Moderate Upstream details at : https://rhn.redhat.com/errata/RHSA-2012-0376.html The following updated files have been uploaded and are currently syncing to the mirrors: ( sha256sum Filename ) i386: 25e6d5acd46e860911b7b445ad9d02d52d2448f74b279dc09a5b2c3b619703c9 systemtap-1.6-7.el5_8.i386.rpm