diff options
| author | dzwdz | 2024-07-12 00:12:06 +0200 |
|---|---|---|
| committer | dzwdz | 2024-07-12 00:12:06 +0200 |
| commit | ded843efbdad1ed048fe42c50c8fb68d50bafa51 (patch) | |
| tree | de6b59e3a8e62af367d91f35d2e70d9d54d51975 /src/kernel/vfs/request.c | |
| parent | ed8ff1ff9c4c0f847ffc2ab4624bd999539a0890 (diff) | |
kernel: don't reuse VfsReq allocations for a single process
To use the same testing methodology as when I've introduced request slots:
before:
/ $ iostress 1 1000000 0 > /dev/vtty
run 0: 2585203
1000000 calls, 0 bytes. avg 2585203
after:
/ $ iostress 1 1000000 0 > /dev/vtty
run 0: 2783171
1000000 calls, 0 bytes. avg 2783171
This is around a 7.7% slowdown - that I hope to fix with a better malloc.
While this doesn't really make the code that much simpler, it doesn't feel
like the right approach in the first place
Diffstat (limited to 'src/kernel/vfs/request.c')
| -rw-r--r-- | src/kernel/vfs/request.c | 22 |
1 files changed, 7 insertions, 15 deletions
diff --git a/src/kernel/vfs/request.c b/src/kernel/vfs/request.c index 4489f5a..d4ea16c 100644 --- a/src/kernel/vfs/request.c +++ b/src/kernel/vfs/request.c @@ -33,19 +33,7 @@ vfsreq_dispatchcopy(VfsReq tmpl) VfsBackend *backend; /* allocate memory for the request and move it there */ - if (tmpl.caller) { - // TODO: ensure we aren't overriding an existing request - // TODO: wouldn't it be better to just optimize malloc? - // see commit afa28cfc7069f7649632f7b33daac47ee56d3819 - proc_setstate(tmpl.caller, PS_WAITS4FS); - if (!tmpl.caller->reqslot) - tmpl.caller->reqslot = kmalloc(sizeof *req, "reqslot"); - req = tmpl.caller->reqslot; - /* (re)using a single allocation for all request a process makes */ - } else { - req = kmalloc(sizeof *req, "reqanon"); - } - + req = kmalloc(sizeof *req, "VfsReq"); memcpy(req, &tmpl, sizeof *req); backend = req->backend; if (backend) { @@ -53,6 +41,11 @@ vfsreq_dispatchcopy(VfsReq tmpl) backend->usehcnt++; } + if (req->caller) { + proc_setstate(req->caller, PS_WAITS4FS); + req->caller->reqslot = req; + } + /* Check request validity. Doing this after the memcpy means that it * doesn't need to be special cased in vfsreq_finish. */ if (!vfsreq_isvalid(req)) { @@ -125,9 +118,8 @@ vfsreq_finish(VfsReq *req, char __user *stored, long ret, int flags, Proc *handl assert(req->caller->state == PS_WAITS4FS); regs_savereturn(&req->caller->regs, ret); proc_setstate(req->caller, PS_RUNNING); - } else { - kfree(req); } + kfree(req); } void |