/* $NetBSD: profile.c,v 1.17 2016/07/07 06:55:38 msaitoh Exp $ */
/*
* Copyright 1997
* Digital Equipment Corporation. All rights reserved.
*
* This software is furnished under license and may be used and
* copied only in accordance with the following terms and conditions.
* Subject to these conditions, you may download, copy, install,
* use, modify and distribute this software in source and/or binary
* form. No title or ownership is transferred hereby.
*
* 1) Any source code used, modified or distributed must reproduce
* and retain this copyright notice and list of conditions as
* they appear in the source file.
*
* 2) No right is granted to use any trade name, trademark, or logo of
* Digital Equipment Corporation. Neither the "Digital Equipment
* Corporation" name nor any trademark or logo of Digital Equipment
* Corporation may be used to endorse or promote products derived
* from this software without the prior written permission of
* Digital Equipment Corporation.
*
* 3) This software is provided "AS-IS" and any express or implied
* warranties, including but not limited to, any implied warranties
* of merchantability, fitness for a particular purpose, or
* non-infringement are disclaimed. In no event shall DIGITAL be
* liable for any damages whatsoever, and in particular, DIGITAL
* shall not be liable for special, indirect, consequential, or
* incidental damages or damages for lost profits, loss of
* revenue or loss of use, whether such damages arise in contract,
* negligence, tort, under statute, in equity, at law or otherwise,
* even if advised of the possibility of such damage.
*/
/*
* The fiq based profiler.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: profile.c,v 1.17 2016/07/07 06:55:38 msaitoh Exp $");
#include "profiler.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/time.h>
#include <sys/proc.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/errno.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <shark/shark/hat.h>
#include <machine/profileio.h>
#include <dev/ic/i8253reg.h>
#define PROFILER_DEBUG 1
#define countPerTick 500 /* TIMER_FREQ/10000 10 kHz timer */
/* Processor Status Defines */
#define STATUS_MODE_MASK 0x1f
#define USER_MODE 0x10
#define FIQ_MODE 0x11
#define IRQ_MODE 0x12
#define SVC_MODE 0x13
#define ABORT_MODE 0x17
#define UNDEF_MODE 0x1b
#define SYS_MODE 0x1f
/* software controller
*/
struct profiler_sc
{
int state;
#define PROF_OPEN 0x01
#define PROF_PROFILING 0x02
} prof_sc;
/*
* GLOBAL DATA
*/
/* I need my own stack space for the hat */
#define HATSTACKSIZE 1024 /* size of stack used during a FIQ */
static unsigned char hatStack[HATSTACKSIZE]; /* actual stack used
* during a FIQ
*/
/* Pointer to the list of hash tables.
* A backup table is created for every table malloced, this
* is used so that we don't miss samples while copying the
* data out. Thus the actual number of tables in the array is twice
* what nhashTables says.
*/
struct profHashTable *profTable;
struct profHashTable *phashTables[2];
int nhashTables;
/*
* FORWARD DECLARATIONS
*/
static void profFiq(int x);
static void profHatWedge(int nFIQs);
void profStop(void);
void profStart(struct profStartInfo *);
static void profEnter(struct profHashTable * , unsigned int);
void displayTable(struct profHashTable * );
dev_type_open(profopen);
dev_type_close(profclose);
dev_type_read(profread);
dev_type_ioctl(profioctl);
const struct cdevsw prof_cdevsw = {
.d_open = profopen,
.d_close = profclose,
.d_read = profread,
.d_write = nowrite,
.d_ioctl = profioctl,
.d_stop = nostop,
.d_tty = notty,
.d_poll = nopoll,
.d_mmap = nommap,
.d_kqfilter = nokqfilter,
.d_discard = nodiscard,
.d_flag = 0
};
void
profilerattach(int n)
{
/* reset the profiler state */
prof_sc.state = 0;
}
/*
* Open the profiling devicee.
* Returns
* ENXIO for illegal minor device
* ie. if the minor device number is not 0.
* EBUSY if file is open by another process.
* EROFS if attempt to open in write mode.
*/
int
profopen(dev_t dev, int flag, int mode, struct proc *p)
{
/* check that the minor number is correct. */
if (minor(dev) >= NPROFILER)
{
return ENXIO;
}
/* check that the device is not already open. */
if (prof_sc.state && PROF_OPEN)
{
return EBUSY;
}
/* check that the flag is set to read only. */
if (!(flag && FWRITE))
{
return EROFS;
}
/* flag the device as open. */
prof_sc.state |= PROF_OPEN;
nhashTables = 0;
phashTables[0] = phashTables[1] = NULL;
return 0;
}
/*
* Close the descriptor.
*
*/
int
profclose(dev_t dev, int flag, int mode, struct proc *p)
{
/* clear the state, and stop profiling if
* it is happening.
*/
profStop();
prof_sc.state &= ~PROF_OPEN;
return 0;
}
int
profread(dev_t dev, struct uio *uio, int flags)
{
int error;
int real, backup;
/* must be profiling to read */
if (!(prof_sc.state & PROF_PROFILING))
{
error = EINVAL;
}
else
{
if (uio->uio_resid != sizeof(struct profHashHeader) +
profTable->hdr.tableSize * sizeof(struct profHashEntry))
{
printf("profile read size is incorrect!");
error = EINVAL;
}
else
{
/* first work out which table is currently being used.
*/
if (profTable == phashTables[0])
{
real = 0;
backup = 1;
}
else
{
if (profTable == phashTables[1])
{
real = 1;
backup = 0;
}
else
{
panic("profiler lost buffer");
}
}
/* now initialise the backup copy before switching over.
*/
memset(phashTables[backup]->entries, 0,
profTable->hdr.tableSize * sizeof(struct profHashEntry));
/* now initialise the header */
phashTables[backup]->hdr.tableSize = phashTables[real]->hdr.tableSize;
phashTables[backup]->hdr.entries = phashTables[backup]->hdr.last
= phashTables[real]->hdr.entries;
phashTables[backup]->hdr.samples = 0;
phashTables[backup]->hdr.missed = 0;
phashTables[backup]->hdr.fiqs = 0;
phashTables[backup]->hdr.pid = phashTables[real]->hdr.pid;
phashTables[backup]->hdr.mode = phashTables[real]->hdr.mode;
/* ok now swap over.
* I don't worry about locking the fiq while I change
* this, at this point it won't matter which table the
* fiq reads.
*/
profTable = phashTables[backup];
/* don't want to send the pointer,
* make assumption that table follows the header.
*/
if ( (error = uiomove(phashTables[real],
sizeof(struct profHashHeader), uio))
!= 0)
{
printf("uiomove failed error is %d\n", error);
}
else
{
if ( (error = uiomove(phashTables[real]->entries,
phashTables[real]->hdr.tableSize *
sizeof(struct profHashEntry), uio))
!= 0)
{
printf("uiomove failed error is %d\n", error);
}
}
}
}
return error;
}
/*
* PROFIOSTART Start Profiling
* PROFIOSTOP Stop Profiling
*/
static int profcount = 0;
static int ints = 0;
int
profioctl(dev_t dev, u_long cmd, void *data, int flag, struct proc *p)
{
int error = 0;
struct profStartInfo *info = (struct profStartInfo *) data;
switch (cmd)
{
case PROFIOSTART :
profStart(info);
break;
case PROFIOSTOP :
profStop();
break;
default :
error = EINVAL;
break;
}
return error;
}
/* start profiling, returning status information in the
* profStartInfo structure.
*
* presumes pid is running, does no checks here.
*/
void
profStart(struct profStartInfo *info)
{
unsigned int savedInts;
char *buffer;
/* can't already be sampling */
if ( prof_sc.state & PROF_PROFILING )
{
info->status = ALREADY_SAMPLING;
return ;
}
/* sanity check that the table sizes are logical */
if (info->entries > info->tableSize)
{
info->status = BAD_TABLE_SIZE;
return ;
}
/* now sanity check that we are sampling either the
* kernel or a pid or both.
*/
if ( !(info->mode & SAMPLE_MODE_MASK) )
{
info->status = ILLEGAL_COMMAND;
return ;
}
/* alloc two hash tables. */
buffer = malloc(sizeof(struct profHashTable) +
info->tableSize * sizeof(struct profHashEntry),
M_DEVBUF, M_NOWAIT);
if ( (buffer == NULL) )
{
info->status = NO_MEMORY;
return;
}
phashTables[0] = (struct profHashTable *) buffer;
phashTables[0]->entries = (struct profHashEntry *)
( buffer + sizeof(struct profHashTable));
buffer = malloc(sizeof(struct profHashTable) +
info->tableSize * sizeof(struct profHashEntry),
M_DEVBUF, M_NOWAIT);
if ( (buffer == NULL) )
{
free(phashTables[0], M_DEVBUF);
info->status = NO_MEMORY;
return;
}
phashTables[1] = (struct profHashTable *) buffer;
phashTables[1]->entries = (struct profHashEntry *)
( buffer + sizeof(struct profHashTable));
memset(phashTables[0]->entries, 0,
info->tableSize * sizeof(struct profHashEntry));
memset(phashTables[1]->entries, 0,
info->tableSize * sizeof(struct profHashEntry));
/* now initialise the header */
profTable = phashTables[0];
profTable->hdr.tableSize = info->tableSize;
profTable->hdr.entries = profTable->hdr.last = info->entries;
profTable->hdr.samples = 0;
profTable->hdr.missed = 0;
profTable->hdr.fiqs = 0;
profTable->hdr.pid = info->pid;
profTable->hdr.mode = info->mode;
/* now let the pigeons loose. */
savedInts = disable_interrupts(I32_bit | F32_bit);
prof_sc.state |= PROF_PROFILING;
hatClkOn(countPerTick,
profFiq,
(int)&prof_sc,
hatStack + HATSTACKSIZE - sizeof(unsigned),
profHatWedge);
restore_interrupts(savedInts);
}
void
profStop(void)
{
unsigned int savedInts;
int spl;
savedInts = disable_interrupts(I32_bit | F32_bit);
hatClkOff();
restore_interrupts(savedInts);
spl = splbio();
/* only free the buffer's if we were profiling,
* who cares if we were not, won't alert any one.
*/
if (prof_sc.state & PROF_PROFILING)
{
/* now free both buffers. */
free(phashTables[0], M_DEVBUF);
free(phashTables[1], M_DEVBUF);
}
phashTables[0] = phashTables[1] = NULL;
prof_sc.state &= ~PROF_PROFILING;
splx(spl);
}
/*
**++
** FUNCTIONAL DESCRIPTION:
**
** profFiq
**
** This is what the HAT clock calls. This call drives
** the timeout queues, which in turn drive the state machines
**
** Be very carefully when calling a timeout as the function
** that is called may in turn do timeout/untimeout calls
** before returning
**
** FORMAL PARAMETERS:
**
** int x - not used
**
** IMPLICIT INPUTS:
**
** nill
**
** IMPLICIT OUTPUTS:
**
** nill
**
** FUNCTION VALUE:
**
** nill
**
** SIDE EFFECTS:
**
** a timeout may be called if it is due
**--
*/
static void
profFiq(int x)
{
int i;
int *ip; /* the fiq stack pointer */
unsigned int spsr, stacklr; /* the link register, off the stack. */
/* get the link register and see where we came from.
* We do this by getting the stack pointer using,
* an inline assembler instruction and then going 9
* words up to get the return address from the fiq.
*
* NOTE: the stack will change if more local variables
* are added so beware of modifications to this
* function.
* the fiq.S handler puts the following on the stack
* stmfd sp!, {r0-r3, lr}
* then this function does
* mov ip, sp
* stmfd sp!, {r4, fp, ip, lr, pc}
* or some variant of this.
*
* instead of using sp we can use ip, the saved stack pointer
* and be done with the chance of sp changing around on us.
*
* so by the time we get here we have a stack that looks like.
* (see pg 4-23, ARM programming Techniques doco for description
* on stm instructions.)
* lr-fiq (we want this one).
* r3-fiq
* r2-fiq
* r1-fiq
* ip--> r0-fiq
* pc-prof
* lr-prof
* ip-prof
* fp-prof
* sp--> r4-prof
* the sp by the time we get to it will point to r4 at the
* bottom of the stack. So we go 9 up to get the lr we want.
* or even better we have ip pointing to r0 and we can go 4 up
* to get the saved link register.
*
* We are safer this way because fiq.S is coded assembler, we are
* at the mercy of the assembler for our stack.
*
*/
__asm("mov %0, ip" : "=r" (ip) : );
stacklr = *(ip+4);
/* get the spsr register
*/
__asm("mrs %0, spsr" : "=r" (spsr) : );
/* now check whether we want this sample.
* NB. We place kernel and user level samples in the
* same table.
*/
if ( (profTable->hdr.mode & SAMPLE_PROC) &&
((spsr & STATUS_MODE_MASK) == USER_MODE) )
{
if ( curlwp->p_pid == profTable->hdr.pid )
{
profEnter(profTable, stacklr-4);
}
}
if ( profTable->hdr.mode & SAMPLE_KERN )
{
if ( ((spsr & STATUS_MODE_MASK) == SVC_MODE)/* ||
((spsr & STATUS_MODE_MASK) == IRQ_MODE)*/ )
{
/* Note: the link register will be two instructions,
* ahead of the "blamed" instruction. This is actually
* a most likely case and might not actually highlight the
* exact cause of problems, some post processing intelligence
* will be required to make use of this data.
*/
profEnter(profTable, stacklr-4);
}
}
/* increment the samples counter */
profTable->hdr.fiqs++;
}
/*
**++
** FUNCTIONAL DESCRIPTION:
**
** profHatWedge
**
** Called if the HAT timer becomes clogged/wedged. Not
** used by this driver, we let upper layers recover
** from this condition
**
** FORMAL PARAMETERS:
**
** int nFIQs - not used
**
** IMPLICIT INPUTS:
**
** nill
**
** IMPLICIT OUTPUTS:
**
** nill
**
** FUNCTION VALUE:
**
** nill
**
** SIDE EFFECTS:
**
** nill
**--
*/
static void
profHatWedge(int nFIQs)
{
#ifdef PROFILER_DEBUG
printf("profHatWedge: nFIQ = %d\n",nFIQs);
#endif
}
/* Enter the data in the table.
*
* To reduce the time taken to find samples with time
* an eviction algorithm is implemented.
* When a new entry in the overflow area is required
* the first entry in the hash table is copied there
* and the new entry placed as the hash table entry. The
* displaced entry will then be the first entry accessed in
* the table.
*/
static void
profEnter(struct profHashTable *table, unsigned int lr)
{
unsigned int entries, hashShift, index, count;
struct profHashEntry *sample;
struct profHashEntry *first;
struct profHashEntry *prev;
struct profHashEntry tmpEntry;
int tmpIndex;
/* work out how many bits
* are required to hash the given size.
*/
entries = table->hdr.entries - 1;
hashShift = 0;
do
{
entries = entries << 1;
hashShift++;
} while (!(entries & 0x80000000));
/* enter the pc in the table. */
/* remove redundant bits.
* and save the count offset bits
*/
lr = lr >> REDUNDANT_BITS;
count = lr & COUNT_BIT_MASK;
lr = lr >> COUNT_BITS;
/* this is easier than working out how
* many bits to or, based on the hashShift.
* maybe it would be better to work out at
* the start and save time during the fiq.
*/
index = (lr << hashShift) >> hashShift;
first = sample = &table->entries[index];
/* now loop until we either find the entry
* or the next free space.
*/
while ( (sample->pc != lr) && (table->hdr.last < table->hdr.tableSize) )
{
if (sample->pc == 0)
{
/* go ahead and stick it in */
sample->pc = lr;
}
else
{
if (sample->next != 0)
{
/* move along and continue */
prev = sample;
sample = &table->entries[sample->next];
}
else
{
/* create a new entry if available */
if (table->hdr.last < table->hdr.tableSize)
{
sample = &table->entries[table->hdr.last];
/* copy the first sample into the new
* field.
*/
memcpy(sample, first, sizeof(struct profHashEntry));
/* now update the new entry in the first position.
*/
first->pc = lr;
first->next = table->hdr.last;
first->counts[0] = 0;
first->counts[1] = 0;
first->counts[2] = 0;
first->counts[3] = 0;
table->hdr.last++;
/* update the sample pointer so that we
* can insert the count.
*/
sample = first;
}
}
}
}
/* check if we need to do an eviction. */
if (sample != first)
{
/* copy the sample out of the table. */
memcpy(&tmpEntry, sample, sizeof(struct profHashEntry));
/* remove the sample from the chain. */
tmpIndex = prev->next;
prev->next = sample->next;
/* now insert it at the beginning. */
memcpy(sample, first, sizeof(struct profHashEntry));
memcpy(first, &tmpEntry, sizeof(struct profHashEntry));
/* now make the new first entry point to the old
* first entry.
*/
first->next = tmpIndex;
}
/* must now check the lr
* to see if the table is full.
*/
if (sample->pc == lr)
{
/* update the count */
sample->counts[count]++;
table->hdr.samples++;
}
else
{
table->hdr.missed++;
}
}
void
displayTable(struct profHashTable *table)
{
int i;
struct profHashEntry *sample;
char buff[100] = ".............................................\n";
for (i=0; i < table->hdr.tableSize; i++)
{
sample = &table->entries[i];
if ((i * table->hdr.tableSize) >= table->hdr.entries)
{
printf("%s", buff);
buff[0] = '\0';
}
printf("i = %d, pc = 0x%x, next = %d, counts %d %d %d %d\n",
i, sample->pc, sample->next, sample->counts[0],
sample->counts[1], sample->counts[2], sample->counts[3]);
}
return;
}