diff options
| author | ryo <ryo@NetBSD.org> | 2022-12-01 00:27:59 +0000 |
|---|---|---|
| committer | ryo <ryo@NetBSD.org> | 2022-12-01 00:27:59 +0000 |
| commit | 496cc17fa789c491a616c3fc0e2e456170fca3c4 (patch) | |
| tree | e18779b9cef9b396dd6da3f57fdf7ca9fc4d299b /sys/dev | |
| parent | 3070a019febb77231d421dcfc630626113ac8f7d (diff) | |
don't call kpreempt_{disable,enable}() from an interrupt handler.
Fixed a problem in which the system would freeze if a high load (e.g., build.sh -j20)
was applied while running `tprof monitor -e LsNotHaltedCyc ...' on x86.
This almost eliminates the problem, but still is not enough. tprof_x86 uses NMI
interrupts, which are interrupted even in splhigh(), leaving the possibility of
being interrupted in the splhigh section of percpu_cpu_swap().
Diffstat (limited to 'sys/dev')
| -rw-r--r-- | sys/dev/tprof/tprof.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/sys/dev/tprof/tprof.c b/sys/dev/tprof/tprof.c index f09e486828d..fedb8fc104c 100644 --- a/sys/dev/tprof/tprof.c +++ b/sys/dev/tprof/tprof.c @@ -1,4 +1,4 @@ -/* $NetBSD: tprof.c,v 1.17 2022/03/28 12:33:21 riastradh Exp $ */ +/* $NetBSD: tprof.c,v 1.18 2022/12/01 00:27:59 ryo Exp $ */ /*- * Copyright (c)2008,2009,2010 YAMAMOTO Takashi, @@ -27,7 +27,7 @@ */ #include <sys/cdefs.h> -__KERNEL_RCSID(0, "$NetBSD: tprof.c,v 1.17 2022/03/28 12:33:21 riastradh Exp $"); +__KERNEL_RCSID(0, "$NetBSD: tprof.c,v 1.18 2022/12/01 00:27:59 ryo Exp $"); #include <sys/param.h> #include <sys/systm.h> @@ -115,9 +115,18 @@ static kcondvar_t tprof_cv; /* L: */ static struct tprof_stat tprof_stat; /* L: */ static tprof_cpu_t * +tprof_cpu_direct(struct cpu_info *ci) +{ + tprof_cpu_t **cp; + + cp = percpu_getptr_remote(tprof_cpus, ci); + return *cp; +} + +static tprof_cpu_t * tprof_cpu(struct cpu_info *ci) { - tprof_cpu_t **cp, *c; + tprof_cpu_t *c; /* * As long as xcalls are blocked -- e.g., by kpreempt_disable @@ -126,8 +135,7 @@ tprof_cpu(struct cpu_info *ci) * moved to a new buffer, but we can safely read from it. */ kpreempt_disable(); - cp = percpu_getptr_remote(tprof_cpus, ci); - c = *cp; + c = tprof_cpu_direct(ci); kpreempt_enable(); return c; @@ -433,7 +441,7 @@ tprof_backend_lookup(const char *name) void tprof_sample(void *unused, const tprof_frame_info_t *tfi) { - tprof_cpu_t * const c = tprof_curcpu(); + tprof_cpu_t * const c = tprof_cpu_direct(curcpu()); tprof_buf_t * const buf = c->c_buf; tprof_sample_t *sp; const uintptr_t pc = tfi->tfi_pc; |
