Patch to fix recv() syscall missing in ARM syscall list. Patch from lttng mailing list that fixes kernel timestamps being off by about ~2 seconds on 32-bit systems. Additional patch to fix compilation bug on non-X86 introduced by previous patch.
Signed-off-by: Trent Piepho <[email protected]> --- ...trumentation-Add-recv-to-ARM-syscall-tabl.patch | 54 ++++++ ...0002-Fix-nmi-safe-clock-on-32-bit-systems.patch | 188 +++++++++++++++++++++ ...Fix-trace-clock-wrapper-to-compile-on-ARM.patch | 32 ++++ 3 files changed, 274 insertions(+) create mode 100644 package/lttng-modules/0001-syscall-instrumentation-Add-recv-to-ARM-syscall-tabl.patch create mode 100644 package/lttng-modules/0002-Fix-nmi-safe-clock-on-32-bit-systems.patch create mode 100644 package/lttng-modules/0003-Fix-trace-clock-wrapper-to-compile-on-ARM.patch diff --git a/package/lttng-modules/0001-syscall-instrumentation-Add-recv-to-ARM-syscall-tabl.patch b/package/lttng-modules/0001-syscall-instrumentation-Add-recv-to-ARM-syscall-tabl.patch new file mode 100644 index 0000000..f65a5d4 --- /dev/null +++ b/package/lttng-modules/0001-syscall-instrumentation-Add-recv-to-ARM-syscall-tabl.patch @@ -0,0 +1,54 @@ +From 318aba6e68e0338656909b207a96566c54becc85 Mon Sep 17 00:00:00 2001 +From: Trent Piepho <[email protected]> +Date: Wed, 22 Feb 2017 12:56:08 -0800 +Subject: [PATCH] syscall instrumentation: Add recv() to ARM syscall table + +This was missing for some reason. +--- + instrumentation/syscalls/3.4.25/arm-32-syscalls-3.4.25 | 1 + + .../syscalls/headers/arm-32-syscalls-3.4.25_pointers.h | 10 ++++++++++ + 2 files changed, 11 insertions(+) + +diff --git a/instrumentation/syscalls/3.4.25/arm-32-syscalls-3.4.25 b/instrumentation/syscalls/3.4.25/arm-32-syscalls-3.4.25 +index 65c3973..c2e2429 100644 +--- a/instrumentation/syscalls/3.4.25/arm-32-syscalls-3.4.25 ++++ b/instrumentation/syscalls/3.4.25/arm-32-syscalls-3.4.25 +@@ -221,6 +221,7 @@ syscall sys_getpeername nr 287 nbargs 3 types: (int, struct sockaddr *, int *) a + syscall sys_socketpair nr 288 nbargs 4 types: (int, int, int, int *) args: (family, type, protocol, usockvec) + syscall sys_send nr 289 nbargs 4 types: (int, void *, size_t, unsigned) args: (fd, buff, len, flags) + syscall sys_sendto nr 290 nbargs 6 types: (int, void *, size_t, unsigned, struct sockaddr *, int) args: (fd, buff, len, flags, addr, addr_len) ++syscall sys_recv nr 291 nbargs 4 types: (int, void *, size_t, unsigned int) args: (fd, ubuf, size, flags) + syscall sys_recvfrom nr 292 nbargs 6 types: (int, void *, size_t, unsigned, struct sockaddr *, int *) args: (fd, ubuf, size, flags, addr, addr_len) + syscall sys_shutdown nr 293 nbargs 2 types: (int, int) args: (fd, how) + syscall sys_setsockopt nr 294 nbargs 5 types: (int, int, int, char *, int) args: (fd, level, optname, optval, optlen) +diff --git a/instrumentation/syscalls/headers/arm-32-syscalls-3.4.25_pointers.h b/instrumentation/syscalls/headers/arm-32-syscalls-3.4.25_pointers.h +index 76aab1b..05aae76 100644 +--- a/instrumentation/syscalls/headers/arm-32-syscalls-3.4.25_pointers.h ++++ b/instrumentation/syscalls/headers/arm-32-syscalls-3.4.25_pointers.h +@@ -1024,6 +1024,13 @@ SC_LTTNG_TRACEPOINT_EVENT(send, + TP_FIELDS(sc_exit(ctf_integer(long, ret, ret)) sc_inout(ctf_integer(int, fd, fd)) sc_inout(ctf_integer(void *, buff, buff)) sc_inout(ctf_integer(size_t, len, len)) sc_inout(ctf_integer(unsigned, flags, flags))) + ) + #endif ++#ifndef OVERRIDE_32_recv ++SC_LTTNG_TRACEPOINT_EVENT(recv, ++ TP_PROTO(sc_exit(long ret,) int fd, void * ubuf, size_t size, unsigned int flags), ++ TP_ARGS(sc_exit(ret,) fd, ubuf, size, flags), ++ TP_FIELDS(sc_exit(ctf_integer(long, ret, ret)) sc_inout(ctf_integer(int, fd, fd)) sc_inout(ctf_integer(void *, ubuf, ubuf)) sc_inout(ctf_integer(size_t, size, size)) sc_inout(ctf_integer(unsigned int, flags, flags))) ++) ++#endif + #ifndef OVERRIDE_32_msgsnd + SC_LTTNG_TRACEPOINT_EVENT(msgsnd, + TP_PROTO(sc_exit(long ret,) int msqid, struct msgbuf * msgp, size_t msgsz, int msgflg), +@@ -1762,6 +1769,9 @@ TRACE_SYSCALL_TABLE(send, send, 289, 4) + #ifndef OVERRIDE_TABLE_32_sendto + TRACE_SYSCALL_TABLE(sendto, sendto, 290, 6) + #endif ++#ifndef OVERRIDE_TABLE_32_recv ++TRACE_SYSCALL_TABLE(recv, recv, 291, 4) ++#endif + #ifndef OVERRIDE_TABLE_32_recvfrom + TRACE_SYSCALL_TABLE(recvfrom, recvfrom, 292, 6) + #endif +-- +2.7.0.25.gfc10eb5.dirty + diff --git a/package/lttng-modules/0002-Fix-nmi-safe-clock-on-32-bit-systems.patch b/package/lttng-modules/0002-Fix-nmi-safe-clock-on-32-bit-systems.patch new file mode 100644 index 0000000..91296b8 --- /dev/null +++ b/package/lttng-modules/0002-Fix-nmi-safe-clock-on-32-bit-systems.patch @@ -0,0 +1,188 @@ +From 412bf9d51784b49c71b3ddabb3fc0e2b89a59a97 Mon Sep 17 00:00:00 2001 +From: Mathieu Desnoyers <[email protected]> +Date: Thu, 9 Feb 2017 20:51:29 -0500 +Subject: [PATCH] Fix: nmi-safe clock on 32-bit systems + +On 32-bit systems, the current algorithm assume to have one clock read +per 32-bit LSB overflow period, which is not guaranteed. It also has an +issue on the first clock reads after module load, because the initial +value for the last LSB is 0. It can cause the time to stay stuck at the +same value for a few seconds at the beginning of the trace. + +It only affects 32-bit systems with kernels >= 3.17. + +Fix this by using the non-nmi-safe clock source on 32-bit systems, +except for x86 systems that support double-word cmpxchg (cmpxchg8b). + +Signed-off-by: Mathieu Desnoyers <[email protected]> +--- + wrapper/trace-clock.c | 2 +- + wrapper/trace-clock.h | 82 +++++++++++++++++++-------------------------------- + 2 files changed, 31 insertions(+), 53 deletions(-) + +diff --git a/wrapper/trace-clock.c b/wrapper/trace-clock.c +index d9bc956..8c07942 100644 +--- a/wrapper/trace-clock.c ++++ b/wrapper/trace-clock.c +@@ -24,7 +24,7 @@ + #include <wrapper/trace-clock.h> + + #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0)) +-DEFINE_PER_CPU(local_t, lttng_last_tsc); ++DEFINE_PER_CPU(struct lttng_last_timestamp, lttng_last_tsc); + EXPORT_PER_CPU_SYMBOL(lttng_last_tsc); + #endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,16,0)) */ + +diff --git a/wrapper/trace-clock.h b/wrapper/trace-clock.h +index 496fec4..7f76b1b 100644 +--- a/wrapper/trace-clock.h ++++ b/wrapper/trace-clock.h +@@ -59,65 +59,43 @@ extern struct lttng_trace_clock *lttng_trace_clock; + #define LTTNG_CLOCK_NMI_SAFE_BROKEN + #endif + ++/* ++ * We need clock values to be monotonically increasing per-cpu, which is ++ * not strictly guaranteed by ktime_get_mono_fast_ns(). It is ++ * straightforward to do on architectures with a 64-bit cmpxchg(), but ++ * not so on architectures without 64-bit cmpxchg. ++ */ ++ + #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) \ ++ && (BITS_PER_LONG == 64 || CONFIG_X86_CMPXCHG64) \ + && !defined(LTTNG_CLOCK_NMI_SAFE_BROKEN)) ++#define LTTNG_USE_NMI_SAFE_CLOCK ++#endif + +-DECLARE_PER_CPU(local_t, lttng_last_tsc); ++#ifdef LTTNG_USE_NMI_SAFE_CLOCK + +-#if (BITS_PER_LONG == 32) + /* +- * Fixup "src_now" using the 32 LSB from "last". We need to handle overflow and +- * underflow of the 32nd bit. "last" can be above, below or equal to the 32 LSB +- * of "src_now". ++ * Ensure the variable is aligned on 64-bit for cmpxchg8b on 32-bit ++ * systems. + */ +-static inline u64 trace_clock_fixup(u64 src_now, u32 last) +-{ +- u64 now; ++struct lttng_last_timestamp { ++ u64 v; ++} __attribute__((aligned(sizeof(u64)))); + +- now = src_now & 0xFFFFFFFF00000000ULL; +- now |= (u64) last; +- /* Detect overflow or underflow between now and last. */ +- if ((src_now & 0x80000000U) && !(last & 0x80000000U)) { +- /* +- * If 32nd bit transitions from 1 to 0, and we move forward in +- * time from "now" to "last", then we have an overflow. +- */ +- if (((s32) now - (s32) last) < 0) +- now += 0x0000000100000000ULL; +- } else if (!(src_now & 0x80000000U) && (last & 0x80000000U)) { +- /* +- * If 32nd bit transitions from 0 to 1, and we move backward in +- * time from "now" to "last", then we have an underflow. +- */ +- if (((s32) now - (s32) last) > 0) +- now -= 0x0000000100000000ULL; +- } +- return now; +-} +-#else /* #if (BITS_PER_LONG == 32) */ +-/* +- * The fixup is pretty easy on 64-bit architectures: "last" is a 64-bit +- * value, so we can use last directly as current time. +- */ +-static inline u64 trace_clock_fixup(u64 src_now, u64 last) +-{ +- return last; +-} +-#endif /* #else #if (BITS_PER_LONG == 32) */ ++DECLARE_PER_CPU(struct lttng_last_timestamp, lttng_last_tsc); + + /* + * Sometimes called with preemption enabled. Can be interrupted. + */ + static inline u64 trace_clock_monotonic_wrapper(void) + { +- u64 now; +- unsigned long last, result; +- local_t *last_tsc; ++ u64 now, last, result; ++ struct lttng_last_timestamp *last_tsc_ptr; + + /* Use fast nmi-safe monotonic clock provided by the Linux kernel. */ + preempt_disable(); +- last_tsc = lttng_this_cpu_ptr(<tng_last_tsc); +- last = local_read(last_tsc); ++ last_tsc_ptr = lttng_this_cpu_ptr(<tng_last_tsc); ++ last = last_tsc_ptr->v; + /* + * Read "last" before "now". It is not strictly required, but it ensures + * that an interrupt coming in won't artificially trigger a case where +@@ -126,9 +104,9 @@ static inline u64 trace_clock_monotonic_wrapper(void) + */ + barrier(); + now = ktime_get_mono_fast_ns(); +- if (((long) now - (long) last) < 0) +- now = trace_clock_fixup(now, last); +- result = local_cmpxchg(last_tsc, last, (unsigned long) now); ++ if (U64_MAX / 2 < now - last) ++ now = last; ++ result = cmpxchg64_local(&last_tsc_ptr->v, last, now); + preempt_enable(); + if (result == last) { + /* Update done. */ +@@ -139,11 +117,11 @@ static inline u64 trace_clock_monotonic_wrapper(void) + * "result", since it has been sampled concurrently with our + * time read, so it should not be far from "now". + */ +- return trace_clock_fixup(now, result); ++ return result; + } + } + +-#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0)) */ ++#else /* #ifdef LTTNG_USE_NMI_SAFE_CLOCK */ + static inline u64 trace_clock_monotonic_wrapper(void) + { + ktime_t ktime; +@@ -158,7 +136,7 @@ static inline u64 trace_clock_monotonic_wrapper(void) + ktime = ktime_get(); + return ktime_to_ns(ktime); + } +-#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0)) */ ++#endif /* #else #ifdef LTTNG_USE_NMI_SAFE_CLOCK */ + + static inline u64 trace_clock_read64_monotonic(void) + { +@@ -185,19 +163,19 @@ static inline const char *trace_clock_description_monotonic(void) + return "Monotonic Clock"; + } + +-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0)) ++#ifdef LTTNG_USE_NMI_SAFE_CLOCK + static inline int get_trace_clock(void) + { + printk_once(KERN_WARNING "LTTng: Using mainline kernel monotonic fast clock, which is NMI-safe.\n"); + return 0; + } +-#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0)) */ ++#else /* #ifdef LTTNG_USE_NMI_SAFE_CLOCK */ + static inline int get_trace_clock(void) + { + printk_once(KERN_WARNING "LTTng: Using mainline kernel monotonic clock. NMIs will not be traced.\n"); + return 0; + } +-#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0)) */ ++#endif /* #else #ifdef LTTNG_USE_NMI_SAFE_CLOCK */ + + static inline void put_trace_clock(void) + { +-- +2.7.0.25.gfc10eb5.dirty + diff --git a/package/lttng-modules/0003-Fix-trace-clock-wrapper-to-compile-on-ARM.patch b/package/lttng-modules/0003-Fix-trace-clock-wrapper-to-compile-on-ARM.patch new file mode 100644 index 0000000..15708b8 --- /dev/null +++ b/package/lttng-modules/0003-Fix-trace-clock-wrapper-to-compile-on-ARM.patch @@ -0,0 +1,32 @@ +From f69bf94310f0da5ed1791b0da4c1420b235d4b8b Mon Sep 17 00:00:00 2001 +From: Trent Piepho <[email protected]> +Date: Fri, 3 Mar 2017 14:25:16 -0800 +Subject: [PATCH] Fix trace clock wrapper to compile on ARM + +The X86 only define isn't present. Just assume 64-bit cmpxcng works +on all all the other architectures. +--- + wrapper/trace-clock.h | 6 +++++- + 1 file changed, 5 insertions(+), 1 deletion(-) + +diff --git a/wrapper/trace-clock.h b/wrapper/trace-clock.h +index 7f76b1b..066d5e6 100644 +--- a/wrapper/trace-clock.h ++++ b/wrapper/trace-clock.h +@@ -66,8 +66,12 @@ extern struct lttng_trace_clock *lttng_trace_clock; + * not so on architectures without 64-bit cmpxchg. + */ + ++#if defined(ARCH_X86) && !defined(CONFIG_X86_CMPXCHG64) ++#define LTTNG_NO_CMPXCHG64 ++#endif ++ + #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) \ +- && (BITS_PER_LONG == 64 || CONFIG_X86_CMPXCHG64) \ ++ && !defined(LTTNG_NO_CMPXCHG64) \ + && !defined(LTTNG_CLOCK_NMI_SAFE_BROKEN)) + #define LTTNG_USE_NMI_SAFE_CLOCK + #endif +-- +2.7.0.25.gfc10eb5.dirty + -- 2.7.0.25.gfc10eb5.dirty _______________________________________________ lttng-dev mailing list [email protected] https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
