On Wed, 29 May 2013, Peter Zijlstra wrote:
>
> Hurm.. I don't suppose you have an easy reproducer handy eh? I'll go
> stare at it. At least the current state is better than before, but
> clearly we're not quite there yet.
OK, below is an easy reproducer. Just run it two or three times.
It leaks 129 pages in user->locked_vm each time you run it.
It took me a while to bisect this down from 10,000 syscalls to just 3.
I now have a tool that can generate valid perf test_cases from my fuzzer
traces, which should be useful.
Vince
/* log_to_code output from bisect19.log */
/* by Vince Weaver <vincent.weaver _at_ maine.edu */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include <linux/hw_breakpoint.h>
#include <linux/perf_event.h>
int fd[1024];
struct perf_event_attr pe[1024];
char *mmap_result[1024];
int perf_event_open(struct perf_event_attr *hw_event_uptr,
pid_t pid, int cpu, int group_fd, unsigned long flags) {
return syscall(__NR_perf_event_open,hw_event_uptr, pid, cpu,
group_fd, flags);
}
int main(int argc, char **argv) {
memset(&pe[7],0,sizeof(struct perf_event_attr));
pe[7].type=PERF_TYPE_BREAKPOINT;
pe[7].size=96;
pe[7].config=0x0;
pe[7].sample_type=0; /* 0 */
pe[7].read_format=PERF_FORMAT_ID; /* 4 */
pe[7].inherit=1;
pe[7].pinned=1;
pe[7].exclusive=1;
pe[7].exclude_idle=1;
pe[7].mmap=1;
pe[7].comm=1;
pe[7].task=1;
pe[7].precise_ip=3; /* must have zero skid */
pe[7].exclude_host=1;
pe[7].wakeup_events=1886953739;
pe[7].bp_type=HW_BREAKPOINT_R|HW_BREAKPOINT_W; /*3*/
pe[7].bp_addr=0x60ac86c7;
pe[7].bp_len=0x1;
fd[7]=perf_event_open(&pe[7],0,0,-1,0 /*0*/ );
mmap_result[7]=mmap(NULL, 129*4096,PROT_READ|PROT_WRITE, MAP_SHARED,fd[7], 0);
if (mmap_result[7]==MAP_FAILED) {
printf("MMAP FAILED!\n");
exit(1);
}
memset(&pe[8],0,sizeof(struct perf_event_attr));
pe[8].type=PERF_TYPE_HARDWARE;
pe[8].size=96;
pe[8].config=PERF_COUNT_HW_BUS_CYCLES;
pe[8].sample_type=0; /* 0 */
pe[8].read_format=PERF_FORMAT_ID; /* 4 */
pe[8].disabled=1;
pe[8].inherit=1;
pe[8].pinned=1;
pe[8].exclude_kernel=1;
pe[8].comm=1;
pe[8].watermark=1;
pe[8].precise_ip=0; /* arbitrary skid */
pe[8].sample_id_all=1;
pe[8].exclude_guest=1;
pe[8].wakeup_watermark=1153443849;
pe[8].bp_type=HW_BREAKPOINT_EMPTY;
fd[8]=perf_event_open(&pe[8],0,0,fd[7],PERF_FLAG_FD_NO_GROUP|PERF_FLAG_FD_OUTPUT /*3*/ );
/* Replayed 3 syscalls */
return 0;
}
--
To unsubscribe from this list: send the line "unsubscribe trinity" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
