linux/kernel/events/core.c, branch v3.19

perf: Tighten (and fix) the grouping condition

2015-01-28T12:17:35Z

The fix from 9fc81d87420d ("perf: Fix events installation during moving group") was incomplete in that it failed to recognise that creating a group with events for different CPUs is semantically broken -- they cannot be co-scheduled. Furthermore, it leads to real breakage where, when we create an event for CPU Y and then migrate it to form a group on CPU X, the code gets confused where the counter is programmed -- triggered in practice as well by me via the perf fuzzer. Fix this by tightening the rules for creating groups. Only allow grouping of counters that can be co-scheduled in the same context. This means for the same task and/or the same cpu. Fixes: 9fc81d87420d ("perf: Fix events installation during moving group") Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20150123125834.090683288@infradead.org Signed-off-by: Ingo Molnar

perf: Move task_pt_regs sampling into arch code

2015-01-09T10:12:28Z

On x86_64, at least, task_pt_regs may be only partially initialized in many contexts, so x86_64 should not use it without extra care from interrupt context, let alone NMI context. This will allow x86_64 to override the logic and will supply some scratch space to use to make a cleaner copy of user regs. Tested-by: Jiri Olsa Signed-off-by: Andy Lutomirski Signed-off-by: Peter Zijlstra (Intel) Cc: Stephane Eranian Cc: chenggang.qcg@taobao.com Cc: Wu Fengguang Cc: Namhyung Kim Cc: Mike Galbraith Cc: Arjan van de Ven Cc: David Ahern Cc: Arnaldo Carvalho de Melo Cc: Catalin Marinas Cc: Jean Pihet Cc: Linus Torvalds Cc: Mark Salter Cc: Russell King Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/e431cd4c18c2e1c44c774f10758527fb2d1025c4.1420396372.git.luto@amacapital.net Signed-off-by: Ingo Molnar

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-12-19T21:15:24Z

Pull perf fixes and cleanups from Ingo Molnar: "A kernel fix plus mostly tooling fixes, but also some tooling restructuring and cleanups" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) perf: Fix building warning on ARM 32 perf symbols: Fix use after free in filename__read_build_id perf evlist: Use roundup_pow_of_two tools: Adopt roundup_pow_of_two perf tools: Make the mmap length autotuning more robust tools: Adopt rounddown_pow_of_two and deps tools: Adopt fls_long and deps tools: Move bitops.h from tools/perf/util to tools/ tools: Introduce asm-generic/bitops.h tools lib: Move asm-generic/bitops/find.h code to tools/include and tools/lib tools: Whitespace prep patches for moving bitops.h tools: Move code originally from asm-generic/atomic.h into tools/include/asm-generic/ tools: Move code originally from linux/log2.h to tools/include/linux/ tools: Move __ffs implementation to tools/include/asm-generic/bitops/__ffs.h perf evlist: Do not use hard coded value for a mmap_pages default perf trace: Let the perf_evlist__mmap autosize the number of pages to use perf evlist: Improve the strerror_mmap method perf evlist: Clarify sterror_mmap variable names perf evlist: Fixup brown paper bag on "hint" for --mmap-pages cmdline arg perf trace: Provide a better explanation when mmap fails ...

Merge branch 'linus' into perf/urgent, to pick up the upstream merged bits

2014-12-12T08:09:03Z

Signed-off-by: Ingo Molnar

perf: Fix events installation during moving group

2014-12-11T10:24:15Z

We allow PMU driver to change the cpu on which the event should be installed to. This happened in patch: e2d37cd213dc ("perf: Allow the PMU driver to choose the CPU on which to install events") This patch also forces all the group members to follow the currently opened events cpu if the group happened to be moved. This and the change of event->cpu in perf_install_in_context() function introduced in: 0cda4c023132 ("perf: Introduce perf_pmu_migrate_context()") forces group members to change their event->cpu, if the currently-opened-event's PMU changed the cpu and there is a group move. Above behaviour causes problem for breakpoint events, which uses event->cpu to touch cpu specific data for breakpoints accounting. By changing event->cpu, some breakpoints slots were wrongly accounted for given cpu. Vinces's perf fuzzer hit this issue and caused following WARN on my setup: WARNING: CPU: 0 PID: 20214 at arch/x86/kernel/hw_breakpoint.c:119 arch_install_hw_breakpoint+0x142/0x150() Can't find any breakpoint slot [...] This patch changes the group moving code to keep the event's original cpu. Reported-by: Vince Weaver Signed-off-by: Jiri Olsa Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Vince Weaver Cc: Yan, Zheng Cc: Link: http://lkml.kernel.org/r/1418243031-20367-3-git-send-email-jolsa@kernel.org Signed-off-by: Ingo Molnar

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2014-12-11T00:10:49Z

Pull VFS changes from Al Viro: "First pile out of several (there _definitely_ will be more). Stuff in this one: - unification of d_splice_alias()/d_materialize_unique() - iov_iter rewrite - killing a bunch of ->f_path.dentry users (and f_dentry macro). Getting that completed will make life much simpler for unionmount/overlayfs, since then we'll be able to limit the places sensitive to file _dentry_ to reasonably few. Which allows to have file_inode(file) pointing to inode in a covered layer, with dentry pointing to (negative) dentry in union one. Still not complete, but much closer now. - crapectomy in lustre (dead code removal, mostly) - "let's make seq_printf return nothing" preparations - assorted cleanups and fixes There _definitely_ will be more piles" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) copy_from_iter_nocache() new helper: iov_iter_kvec() csum_and_copy_..._iter() iov_iter.c: handle ITER_KVEC directly iov_iter.c: convert copy_to_iter() to iterate_and_advance iov_iter.c: convert copy_from_iter() to iterate_and_advance iov_iter.c: get rid of bvec_copy_page_{to,from}_iter() iov_iter.c: convert iov_iter_zero() to iterate_and_advance iov_iter.c: convert iov_iter_get_pages_alloc() to iterate_all_kinds iov_iter.c: convert iov_iter_get_pages() to iterate_all_kinds iov_iter.c: convert iov_iter_npages() to iterate_all_kinds iov_iter.c: iterate_and_advance iov_iter.c: macros for iterating over iov_iter kill f_dentry macro dcache: fix kmemcheck warning in switch_names new helper: audit_file() nfsd_vfs_write(): use file_inode() ncpfs: use file_inode() kill f_dentry uses lockd: get rid of ->f_path.dentry->d_sb ...

Merge branch 'iov_iter' into for-next

2014-12-09T01:39:29Z

kill f_dentry uses

2014-11-19T18:01:25Z

Signed-off-by: Al Viro

perf: Improve the perf_sample_data struct layout

2014-11-16T10:42:04Z

This patch reorders fields in the perf_sample_data struct in order to minimize the number of cachelines touched in perf_sample_data_init(). It also removes some intializations which are redundant with the code in kernel/events/core.c Signed-off-by: Peter Zijlstra (Intel) Link: http://lkml.kernel.org/r/1411559322-16548-7-git-send-email-eranian@google.com Cc: cebbert.lkml@gmail.com Cc: Arnaldo Carvalho de Melo Cc: jolsa@redhat.com Cc: Linus Torvalds Signed-off-by: Ingo Molnar

perf: Add ability to sample machine state on interrupt

2014-11-16T10:41:57Z

Enable capture of interrupted machine state for each sample. Registers to sample are passed per event in the sample_regs_intr bitmask. To sample interrupt machine state, the PERF_SAMPLE_INTR_REGS must be passed in sample_type. The list of available registers is arch dependent and provided by asm/perf_regs.h Registers are laid out as u64 in the order of the bit order of sample_intr_regs. This patch also adds a new ABI version PERF_ATTR_SIZE_VER4 because we extend the perf_event_attr struct with a new u64 field. Reviewed-by: Jiri Olsa Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra (Intel) Cc: cebbert.lkml@gmail.com Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: linux-api@vger.kernel.org Link: http://lkml.kernel.org/r/1411559322-16548-2-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar