From: Corey Minyard Date: Wed, 16 Jul 2014 19:07:13 +0000 (-0500) Subject: ring-buffer: Always run per-cpu ring buffer resize with schedule_work_on() X-Git-Tag: omap-for-v3.17/fixes-against-rc2~186^2~7 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=021c5b34452d52e51664f09b98cd50c5495e74b6;p=pandora-kernel.git ring-buffer: Always run per-cpu ring buffer resize with schedule_work_on() The code for resizing the trace ring buffers has to run the per-cpu resize on the CPU itself. The code was using preempt_off() and running the code for the current CPU directly, otherwise calling schedule_work_on(). At least on RT this could result in the following: |BUG: sleeping function called from invalid context at kernel/rtmutex.c:673 |in_atomic(): 1, irqs_disabled(): 0, pid: 607, name: bash |3 locks held by bash/607: |CPU: 0 PID: 607 Comm: bash Not tainted 3.12.15-rt25+ #124 |(rt_spin_lock+0x28/0x68) |(free_hot_cold_page+0x84/0x3b8) |(free_buffer_page+0x14/0x20) |(rb_update_pages+0x280/0x338) |(ring_buffer_resize+0x32c/0x3dc) |(free_snapshot+0x18/0x38) |(tracing_set_tracer+0x27c/0x2ac) probably via |cd /sys/kernel/debug/tracing/ |echo 1 > events/enable ; sleep 2 |echo 1024 > buffer_size_kb If we just always use schedule_work_on(), there's no need for the preempt_off(). So do that. Link: http://lkml.kernel.org/p/1405537633-31518-1-git-send-email-cminyard@mvista.com Reported-by: Stanislav Meduna Signed-off-by: Corey Minyard Signed-off-by: Steven Rostedt --- Reading git-diff-tree failed