1. 04 Aug, 2015 24 commits
  2. 21 Jul, 2015 14 commits
  3. 13 Jul, 2015 2 commits
    • Palik, Imre's avatar
      perf/x86: Honor the architectural performance monitoring version · 71e33198
      Palik, Imre authored
      [ Upstream commit 2c33645d ]
      
      Architectural performance monitoring, version 1, doesn't support fixed counters.
      
      Currently, even if a hypervisor advertises support for architectural
      performance monitoring version 1, perf may still try to use the fixed
      counters, as the constraints are set up based on the CPU model.
      
      This patch ensures that perf honors the architectural performance monitoring
      version returned by CPUID, and it only uses the fixed counters for version 2
      and above.
      
      (Some of the ideas in this patch came from Peter Zijlstra.)
      Signed-off-by: default avatarImre Palik <imrep@amazon.de>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Anthony Liguori <aliguori@amazon.com>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1433767609-1039-1-git-send-email-imrep.amz@gmail.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      71e33198
    • Oleg Nesterov's avatar
      perf: Fix ring_buffer_attach() RCU sync, again · eb1ea722
      Oleg Nesterov authored
      [ Upstream commit 2f993cf0 ]
      
      While looking for other users of get_state/cond_sync. I Found
      ring_buffer_attach() and it looks obviously buggy?
      
      Don't we need to ensure that we have "synchronize" _between_
      list_del() and list_add() ?
      
      IOW. Suppose that ring_buffer_attach() preempts right_after
      get_state_synchronize_rcu() and gp completes before spin_lock().
      
      In this case cond_synchronize_rcu() does nothing and we reuse
      ->rb_entry without waiting for gp in between?
      
      It also moves the ->rcu_pending check under "if (rb)", to make it
      more readable imo.
      Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: dave@stgolabs.net
      Cc: der.herr@hofr.at
      Cc: josh@joshtriplett.org
      Cc: tj@kernel.org
      Fixes: b69cf536 ("perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()")
      Link: http://lkml.kernel.org/r/20150530200425.GA15748@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      eb1ea722