b2: fix locking window when getting mutipart upload URL

Before this change, the lock was held while the upload URL was being
fetched from the server.

This meant that any other threads were blocked from getting upload
URLs unecessarily.

It also increased the potential for deadlock.
This commit is contained in:
Nick Craig-Wood 2023-09-25 11:13:40 +01:00
parent 96438ff259
commit 5c48102ede

View File

@ -169,24 +169,26 @@ func (f *Fs) newLargeUpload(ctx context.Context, o *Object, in io.Reader, src fs
// This should be returned with returnUploadURL when finished // This should be returned with returnUploadURL when finished
func (up *largeUpload) getUploadURL(ctx context.Context) (upload *api.GetUploadPartURLResponse, err error) { func (up *largeUpload) getUploadURL(ctx context.Context) (upload *api.GetUploadPartURLResponse, err error) {
up.uploadMu.Lock() up.uploadMu.Lock()
defer up.uploadMu.Unlock() if len(up.uploads) > 0 {
if len(up.uploads) == 0 {
opts := rest.Opts{
Method: "POST",
Path: "/b2_get_upload_part_url",
}
var request = api.GetUploadPartURLRequest{
ID: up.id,
}
err := up.f.pacer.Call(func() (bool, error) {
resp, err := up.f.srv.CallJSON(ctx, &opts, &request, &upload)
return up.f.shouldRetry(ctx, resp, err)
})
if err != nil {
return nil, fmt.Errorf("failed to get upload URL: %w", err)
}
} else {
upload, up.uploads = up.uploads[0], up.uploads[1:] upload, up.uploads = up.uploads[0], up.uploads[1:]
up.uploadMu.Unlock()
return upload, nil
}
up.uploadMu.Unlock()
opts := rest.Opts{
Method: "POST",
Path: "/b2_get_upload_part_url",
}
var request = api.GetUploadPartURLRequest{
ID: up.id,
}
err = up.f.pacer.Call(func() (bool, error) {
resp, err := up.f.srv.CallJSON(ctx, &opts, &request, &upload)
return up.f.shouldRetry(ctx, resp, err)
})
if err != nil {
return nil, fmt.Errorf("failed to get upload URL: %w", err)
} }
return upload, nil return upload, nil
} }