From 345c25730d085c45622ac779da4dbd97dc3a10fe Mon Sep 17 00:00:00 2001 From: Barry Kasindorf Date: Tue, 22 Jul 2008 21:08:54 +0200 Subject: x86/oprofile: add IBS support for AMD CPUs, IBS buffer handling routines This patchset supports the new profiling hardware available in the latest AMD CPUs in the oProfile driver. Signed-off-by: Barry Kasindorf Signed-off-by: Robert Richter Cc: oprofile-list Signed-off-by: Ingo Molnar --- drivers/oprofile/buffer_sync.c | 72 +++++++++++++++++++++++++++++++++++++++++- drivers/oprofile/cpu_buffer.c | 68 ++++++++++++++++++++++++++++++++++++++- drivers/oprofile/cpu_buffer.h | 2 ++ 3 files changed, 140 insertions(+), 2 deletions(-) (limited to 'drivers/oprofile') diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c index 615929f6f0c..e1782d2df09 100644 --- a/drivers/oprofile/buffer_sync.c +++ b/drivers/oprofile/buffer_sync.c @@ -5,6 +5,7 @@ * @remark Read the file COPYING * * @author John Levon + * @author Barry Kasindorf * * This is the core of the buffer management. Each * CPU buffer is processed and entered into the @@ -272,7 +273,7 @@ static void increment_tail(struct oprofile_cpu_buffer *b) { unsigned long new_tail = b->tail_pos + 1; - rmb(); + rmb(); /* be sure fifo pointers are synchromized */ if (new_tail < b->buffer_size) b->tail_pos = new_tail; @@ -327,6 +328,67 @@ static void add_trace_begin(void) add_event_entry(TRACE_BEGIN_CODE); } +#define IBS_FETCH_CODE_SIZE 2 +#define IBS_OP_CODE_SIZE 5 +#define IBS_EIP(offset) \ + (((struct op_sample *)&cpu_buf->buffer[(offset)])->eip) +#define IBS_EVENT(offset) \ + (((struct op_sample *)&cpu_buf->buffer[(offset)])->event) + +/* + * Add IBS fetch and op entries to event buffer + */ +static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code, + int in_kernel, struct mm_struct *mm) +{ + unsigned long rip; + int i, count; + unsigned long ibs_cookie = 0; + off_t offset; + + increment_tail(cpu_buf); /* move to RIP entry */ + + rip = IBS_EIP(cpu_buf->tail_pos); + +#ifdef __LP64__ + rip += IBS_EVENT(cpu_buf->tail_pos) << 32; +#endif + + if (mm) { + ibs_cookie = lookup_dcookie(mm, rip, &offset); + + if (ibs_cookie == NO_COOKIE) + offset = rip; + if (ibs_cookie == INVALID_COOKIE) { + atomic_inc(&oprofile_stats.sample_lost_no_mapping); + offset = rip; + } + if (ibs_cookie != last_cookie) { + add_cookie_switch(ibs_cookie); + last_cookie = ibs_cookie; + } + } else + offset = rip; + + add_event_entry(ESCAPE_CODE); + add_event_entry(code); + add_event_entry(offset); /* Offset from Dcookie */ + + /* we send the Dcookie offset, but send the raw Linear Add also*/ + add_event_entry(IBS_EIP(cpu_buf->tail_pos)); + add_event_entry(IBS_EVENT(cpu_buf->tail_pos)); + + if (code == IBS_FETCH_CODE) + count = IBS_FETCH_CODE_SIZE; /*IBS FETCH is 2 int64s*/ + else + count = IBS_OP_CODE_SIZE; /*IBS OP is 5 int64s*/ + + for (i = 0; i < count; i++) { + increment_tail(cpu_buf); + add_event_entry(IBS_EIP(cpu_buf->tail_pos)); + add_event_entry(IBS_EVENT(cpu_buf->tail_pos)); + } +} static void add_sample_entry(unsigned long offset, unsigned long event) { @@ -524,6 +586,14 @@ void sync_buffer(int cpu) } else if (s->event == CPU_TRACE_BEGIN) { state = sb_bt_start; add_trace_begin(); + } else if (s->event == IBS_FETCH_BEGIN) { + state = sb_bt_start; + add_ibs_begin(cpu_buf, + IBS_FETCH_CODE, in_kernel, mm); + } else if (s->event == IBS_OP_BEGIN) { + state = sb_bt_start; + add_ibs_begin(cpu_buf, + IBS_OP_CODE, in_kernel, mm); } else { struct mm_struct *oldmm = mm; diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c index 2450b3a393f..c9ac4e15691 100644 --- a/drivers/oprofile/cpu_buffer.c +++ b/drivers/oprofile/cpu_buffer.c @@ -5,6 +5,7 @@ * @remark Read the file COPYING * * @author John Levon + * @author Barry Kasindorf * * Each CPU has a local buffer that stores PC value/event * pairs. We also log context switches when we notice them. @@ -207,7 +208,7 @@ static int log_sample(struct oprofile_cpu_buffer * cpu_buf, unsigned long pc, return 1; } -static int oprofile_begin_trace(struct oprofile_cpu_buffer * cpu_buf) +static int oprofile_begin_trace(struct oprofile_cpu_buffer *cpu_buf) { if (nr_available_slots(cpu_buf) < 4) { cpu_buf->sample_lost_overflow++; @@ -252,6 +253,71 @@ void oprofile_add_sample(struct pt_regs * const regs, unsigned long event) oprofile_add_ext_sample(pc, regs, event, is_kernel); } +#define MAX_IBS_SAMPLE_SIZE 14 +static int log_ibs_sample(struct oprofile_cpu_buffer *cpu_buf, + unsigned long pc, int is_kernel, unsigned int *ibs, int ibs_code) +{ + struct task_struct *task; + + cpu_buf->sample_received++; + + if (nr_available_slots(cpu_buf) < MAX_IBS_SAMPLE_SIZE) { + cpu_buf->sample_lost_overflow++; + return 0; + } + + is_kernel = !!is_kernel; + + /* notice a switch from user->kernel or vice versa */ + if (cpu_buf->last_is_kernel != is_kernel) { + cpu_buf->last_is_kernel = is_kernel; + add_code(cpu_buf, is_kernel); + } + + /* notice a task switch */ + if (!is_kernel) { + task = current; + + if (cpu_buf->last_task != task) { + cpu_buf->last_task = task; + add_code(cpu_buf, (unsigned long)task); + } + } + + add_code(cpu_buf, ibs_code); + add_sample(cpu_buf, ibs[0], ibs[1]); + add_sample(cpu_buf, ibs[2], ibs[3]); + add_sample(cpu_buf, ibs[4], ibs[5]); + + if (ibs_code == IBS_OP_BEGIN) { + add_sample(cpu_buf, ibs[6], ibs[7]); + add_sample(cpu_buf, ibs[8], ibs[9]); + add_sample(cpu_buf, ibs[10], ibs[11]); + } + + return 1; +} + +void oprofile_add_ibs_sample(struct pt_regs *const regs, + unsigned int * const ibs_sample, u8 code) +{ + int is_kernel = !user_mode(regs); + unsigned long pc = profile_pc(regs); + + struct oprofile_cpu_buffer *cpu_buf = + &per_cpu(cpu_buffer, smp_processor_id()); + + if (!backtrace_depth) { + log_ibs_sample(cpu_buf, pc, is_kernel, ibs_sample, code); + return; + } + + /* if log_sample() fails we can't backtrace since we lost the source + * of this event */ + if (log_ibs_sample(cpu_buf, pc, is_kernel, ibs_sample, code)) + oprofile_ops.backtrace(regs, backtrace_depth); +} + void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event) { struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(cpu_buffer); diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h index c3e366b5226..9c44d004da6 100644 --- a/drivers/oprofile/cpu_buffer.h +++ b/drivers/oprofile/cpu_buffer.h @@ -55,5 +55,7 @@ void cpu_buffer_reset(struct oprofile_cpu_buffer * cpu_buf); /* transient events for the CPU buffer -> event buffer */ #define CPU_IS_KERNEL 1 #define CPU_TRACE_BEGIN 2 +#define IBS_FETCH_BEGIN 3 +#define IBS_OP_BEGIN 4 #endif /* OPROFILE_CPU_BUFFER_H */ -- cgit v1.2.3