diff options
Diffstat (limited to 'kernel/gsp_sema_service.c')
| -rw-r--r-- | kernel/gsp_sema_service.c | 93 |
1 files changed, 74 insertions, 19 deletions
diff --git a/kernel/gsp_sema_service.c b/kernel/gsp_sema_service.c index 444298a..4fd160e 100644 --- a/kernel/gsp_sema_service.c +++ b/kernel/gsp_sema_service.c @@ -3895,6 +3895,51 @@ static int svc_pool_pa_resolve(struct nv_vgpu_device *vgpu, u32 h, u64 va, if (!svc_pool_boot_lookup(va, &pa, &a)) { u32 bprobe = 0; + /* + * r580: the boot cache survives session flushes, but a pool + * page MOVES between sessions (the client's new allocation) + * while the old page often stays readable - the read-back + * proof cannot tell. The client's own page tables are the + * ground truth for where ITS tracker reads, so try the + * structural walk BEFORE trusting the cache: a differing, + * read-proven walk page wins and the cached page stays as the + * fan-out's secondary candidate. Live evidence (r579 boot): + * releases were written to the stale cache pa=0x11e6d9000 + * while the current page was 0x134730000 (the pin) and the + * client's tracker starved; the pool-wr line said + * src=bootcache. + */ + { + u64 wpa2 = 0; + int wap2 = SVC_APERTURE_SYS; + bool walk_hit = false; + + if (!svc_walk_discovered(vgpu, page, &wpa2, &wap2) || + !svc_walk_vaspaces(vgpu, page, &wpa2, &wap2)) + walk_hit = true; + if (walk_hit && + (wpa2 & ~(u64)(SEMA_PAGE_SIZE - 1)) != + (pa & ~(u64)(SEMA_PAGE_SIZE - 1)) && + !svc_pool_pa_identity(va, wpa2)) { + u64 exact = (wpa2 & ~(u64)(SEMA_PAGE_SIZE - 1)) | + (va & (SEMA_PAGE_SIZE - 1)); + + if (!svc_read_ap(vgpu, exact, svc_ap_of(wap2), + &bprobe, sizeof(bprobe))) { + svc_pool_boot_store(va, pa, a); + svc_pool_pa_store(va, exact, wap2); + svc_tr_clear_failure(page); + if (src) + *src = "walk-over-boot"; + svc_pool_pa_note(h, va, exact, + "walk-over-boot"); + *addr = exact; + *ap = wap2; + return 0; + } + } + } + if (!svc_read_ap(vgpu, pa, svc_ap_of(a), &bprobe, sizeof(bprobe))) { svc_tr_clear_failure(page); @@ -25633,6 +25678,32 @@ static int svc_thread(void *arg) * progress. (With two guests, any guest's progress keeps the * loop tight; the next iteration pumps both.) */ + /* + * r580: the completion hint must also run while the pump is + * making progress - the fast path below skips it, and a + * completion burst saturates the event burst budget and drops + * wake-ups (r579 boot: events_dropped=724; the sentinel + * "no postable event (events_n=8 dropped=724)" repeated every + * 0.5 s). A client that starts waiting mid-burst needs the + * 0.5 s re-post even under load; the per-event dedup keeps the + * extra volume bounded. + */ + for (g = 0; g < n_vgpus; g++) { + vgpu = vgpus[g]; + if (time_before(jiffies, + (unsigned long)svc.post_hint_until) && + time_after(jiffies, + (unsigned long)svc.last_hint + HZ / 2)) { + int rc; + + svc.last_hint = jiffies; + rc = gsp_rm_post_all_events(vgpu); + if (gsp_sema_dbg) + pr_info_ratelimited("sema-svc: completion hint rc=%d\n", + rc); + } + } + if (pumped) { msleep(1); continue; @@ -25644,30 +25715,14 @@ static int svc_thread(void *arg) /* * Push-buffer base discovery: a chunked walk of guest * RAM finds the pages whose first push names a - * channel, so a channel that appears with work - * already waiting is pinned and pumped without - * waiting for the rolling sweep. */ svc_pb_discover(vgpu); /* - * Completion hint: re-post the events for a few - * seconds after a completion, so a client that starts - * waiting after the edge-triggered wake-up still - * observes it. + * r580: the completion hint was hoisted above the + * pumped fast path (it must run under load too); it is + * not repeated here. */ - if (time_before(jiffies, - (unsigned long)svc.post_hint_until) && - time_after(jiffies, - (unsigned long)svc.last_hint + HZ / 2)) { - int rc; - - svc.last_hint = jiffies; - rc = gsp_rm_post_all_events(vgpu); - if (gsp_sema_dbg) - pr_info_ratelimited("sema-svc: completion hint rc=%d\n", - rc); - } /* * Fast path for the pushes themselves: every mapped |