From 87f3b6b6fbcbfa715f0d0db3e7a63e65716a6d4e Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Mon, 6 Oct 2008 09:30:12 -0400 Subject: [PATCH] Marker depmod fix core kernel list * Theodore Ts'o (tytso@mit.edu) wrote: > > I've been playing with adding some markers into ext4 to see if they > could be useful in solving some problems along with Systemtap. It > appears, though, that as of 2.6.27-rc8, markers defined in code which is > compiled directly into the kernel (i.e., not as modules) don't show up > in Module.markers: > > kvm_trace_entryexit arch/x86/kvm/kvm-intel %u %p %u %u %u %u %u %u > kvm_trace_handler arch/x86/kvm/kvm-intel %u %p %u %u %u %u %u %u > kvm_trace_entryexit arch/x86/kvm/kvm-amd %u %p %u %u %u %u %u %u > kvm_trace_handler arch/x86/kvm/kvm-amd %u %p %u %u %u %u %u %u > > (Note the lack of any of the kernel_sched_* markers, and the markers I > added for ext4_* and jbd2_* are missing as wel.) > > Systemtap apparently depends on in-kernel trace_mark being recorded in > Module.markers, and apparently it's been claimed that it used to be > there. Is this a bug in systemtap, or in how Module.markers is getting > built? And is there a file that contains the equivalent information > for markers located in non-modules code? I think the problem comes from "markers: fix duplicate modpost entry" (commit d35cb360c29956510b2fe1a953bd4968536f7216) Especially : - add_marker(mod, marker, fmt); + if (!mod->skip) + add_marker(mod, marker, fmt); } return; fail: Here is a fix that should take care if this problem. Thanks for the bug report! Signed-off-by: Mathieu Desnoyers Tested-by: "Theodore Ts'o" CC: Greg KH CC: David Smith CC: Roland McGrath CC: Sam Ravnborg CC: Wenji Huang CC: Takashi Nishiie Signed-off-by: Linus Torvalds --- scripts/mod/modpost.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 418cd7d..8e0de6a 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1986,11 +1986,13 @@ static void read_markers(const char *fname) mod = find_module(modname); if (!mod) { - if (is_vmlinux(modname)) - have_vmlinux = 1; mod = new_module(NOFAIL(strdup(modname))); mod->skip = 1; } + if (is_vmlinux(modname)) { + have_vmlinux = 1; + mod->skip = 0; + } if (!mod->skip) add_marker(mod, marker, fmt); -- 2.7.4