From c5ecceefdb840af45db436adc58219ae97b6ef3c Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 13 Sep 2013 23:39:17 +0200 Subject: perf: Update ABI comment For some mysterious reason the sample_id field of PERF_RECORD_MMAP went AWOL. Reported-by: Vince Weaver Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- include/uapi/linux/perf_event.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 40a1fb807396..7f6d584c267b 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -528,6 +528,7 @@ enum perf_event_type { * u64 len; * u64 pgoff; * char filename[]; + * struct sample_id sample_id; * }; */ PERF_RECORD_MMAP = 1, -- cgit v1.2.3 From fa7315871046b9a4c48627905691dbde57e51033 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 19 Sep 2013 10:16:42 +0200 Subject: perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page' Solve the problems around the broken definition of perf_event_mmap_page:: cap_usr_time and cap_usr_rdpmc fields which used to overlap, partially fixed by: 860f085b74e9 ("perf: Fix broken union in 'struct perf_event_mmap_page'") The problem with the fix (merged in v3.12-rc1 and not yet released officially), noticed by Vince Weaver is that the new behavior is not detectable by new user-space, and that due to the reuse of the field names it's easy to mis-compile a binary if old headers are used on a new kernel or new headers are used on an old kernel. To solve all that make this change explicit, detectable and self-contained, by iterating the ABI the following way: - Always clear bit 0, and rename it to usrpage->cap_bit0, to at least not confuse old user-space binaries. RDPMC will be marked as unavailable to old binaries but that's within the ABI, this is a capability bit. - Rename bit 1 to ->cap_bit0_is_deprecated and always set it to 1, so new libraries can reliably detect that bit 0 is deprecated and perma-zero without having to check the kernel version. - Use bits 2, 3, 4 for the newly defined, correct functionality: cap_user_rdpmc : 1, /* The RDPMC instruction can be used to read counts */ cap_user_time : 1, /* The time_* fields are used */ cap_user_time_zero : 1, /* The time_zero field is used */ - Rename all the bitfield names in perf_event.h to be different from the old names, to make sure it's not possible to mis-compile it accidentally with old assumptions. The 'size' field can then be used in the future to add new fields and it will act as a natural ABI version indicator as well. Also adjust tools/perf/ userspace for the new definitions, noticed by Adrian Hunter. Reported-by: Vince Weaver Signed-off-by: Peter Zijlstra Also-Fixed-by: Adrian Hunter Link: http://lkml.kernel.org/n/tip-zr03yxjrpXesOzzupszqglbv@git.kernel.org Signed-off-by: Ingo Molnar --- include/uapi/linux/perf_event.h | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 7f6d584c267b..009a655a5d35 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -380,10 +380,13 @@ struct perf_event_mmap_page { union { __u64 capabilities; struct { - __u64 cap_usr_time : 1, - cap_usr_rdpmc : 1, - cap_usr_time_zero : 1, - cap_____res : 61; + __u64 cap_bit0 : 1, /* Always 0, deprecated, see commit 860f085b74e9 */ + cap_bit0_is_deprecated : 1, /* Always 1, signals that bit 0 is zero */ + + cap_user_rdpmc : 1, /* The RDPMC instruction can be used to read counts */ + cap_user_time : 1, /* The time_* fields are used */ + cap_user_time_zero : 1, /* The time_zero field is used */ + cap_____res : 59; }; }; @@ -442,12 +445,13 @@ struct perf_event_mmap_page { * ((rem * time_mult) >> time_shift); */ __u64 time_zero; + __u32 size; /* Header size up to __reserved[] fields. */ /* * Hole for extension of the self monitor capabilities */ - __u64 __reserved[119]; /* align to 1k */ + __u8 __reserved[118*8+4]; /* align to 1k. */ /* * Control data for the mmap() data buffer. -- cgit v1.2.3 From 5bc3db5c9ca8407f52918b6504d3b27230defedc Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Mon, 30 Sep 2013 21:30:22 -0700 Subject: tc: export tc_defact.h to userspace Jamal sent patch to add tc user simple actions to iproute2 but required header was not being exported. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/uapi/linux/tc_act/Kbuild | 1 + include/uapi/linux/tc_act/tc_defact.h | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+) create mode 100644 include/uapi/linux/tc_act/tc_defact.h (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/tc_act/Kbuild b/include/uapi/linux/tc_act/Kbuild index 0623ec4e728f..56f121605c99 100644 --- a/include/uapi/linux/tc_act/Kbuild +++ b/include/uapi/linux/tc_act/Kbuild @@ -1,5 +1,6 @@ # UAPI Header export list header-y += tc_csum.h +header-y += tc_defact.h header-y += tc_gact.h header-y += tc_ipt.h header-y += tc_mirred.h diff --git a/include/uapi/linux/tc_act/tc_defact.h b/include/uapi/linux/tc_act/tc_defact.h new file mode 100644 index 000000000000..17dddb40f740 --- /dev/null +++ b/include/uapi/linux/tc_act/tc_defact.h @@ -0,0 +1,19 @@ +#ifndef __LINUX_TC_DEF_H +#define __LINUX_TC_DEF_H + +#include + +struct tc_defact { + tc_gen; +}; + +enum { + TCA_DEF_UNSPEC, + TCA_DEF_TM, + TCA_DEF_PARMS, + TCA_DEF_DATA, + __TCA_DEF_MAX +}; +#define TCA_DEF_MAX (__TCA_DEF_MAX - 1) + +#endif -- cgit v1.2.3 From bf378d341e4873ed928dc3c636252e6895a21f50 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 28 Oct 2013 13:55:29 +0100 Subject: perf: Fix perf ring buffer memory ordering The PPC64 people noticed a missing memory barrier and crufty old comments in the perf ring buffer code. So update all the comments and add the missing barrier. When the architecture implements local_t using atomic_long_t there will be double barriers issued; but short of introducing more conditional barrier primitives this is the best we can do. Reported-by: Victor Kaplansky Tested-by: Victor Kaplansky Signed-off-by: Peter Zijlstra Cc: Mathieu Desnoyers Cc: michael@ellerman.id.au Cc: Paul McKenney Cc: Michael Neuling Cc: Frederic Weisbecker Cc: anton@samba.org Cc: benh@kernel.crashing.org Link: http://lkml.kernel.org/r/20131025173749.GG19466@laptop.lan Signed-off-by: Ingo Molnar --- include/uapi/linux/perf_event.h | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 009a655a5d35..2fc1602e23bb 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -456,13 +456,15 @@ struct perf_event_mmap_page { /* * Control data for the mmap() data buffer. * - * User-space reading the @data_head value should issue an rmb(), on - * SMP capable platforms, after reading this value -- see - * perf_event_wakeup(). + * User-space reading the @data_head value should issue an smp_rmb(), + * after reading this value. * * When the mapping is PROT_WRITE the @data_tail value should be - * written by userspace to reflect the last read data. In this case - * the kernel will not over-write unread data. + * written by userspace to reflect the last read data, after issueing + * an smp_mb() to separate the data read from the ->data_tail store. + * In this case the kernel will not over-write unread data. + * + * See perf_output_put_handle() for the data ordering. */ __u64 data_head; /* head in the data section */ __u64 data_tail; /* user-space written tail */ -- cgit v1.2.3